The Human Fossil Record, Craniodental Morphology of Early Hominids (Genera Australopithecus, Paranthropus, Orrorin), and Overview (Volume 4)

fciC* -afl

HUMAN tji

tf

4

&M m

VOLUME FOUR

i

Craniodental Morphology of Early Hominids (Genera Australopithecus, Paranthropus„Orrorin), and Overview

Jeffrey H. Schwartz an Tattersall ^>

*

^1

rr'

ira

T H E HUMAN FOSSIL RECORD

R 4S£> i Muslim Haftornl d'Histofre Nafurelle bt*»parlGrrit»rit de Frehistoire 1,njoFten£Panh*rd 75013 PARIS

THE HUMAN FOSSIL RECORD Series Editors JEFFREY H. SCHWARTZ Department of Anthropology University of Pittsburgh Pittsburgh, Pennsylvania IAN TATTERSALL Department of Anthropology American Museum of Natural History New York, New York

I eiei o

Wi«,I,

THE HUMAN FOSSIL RECORD Volume Four Craniodental Morphology of Early Hominids (Genera Australopithecus, Paranthropus, Orrorin) and Overview

Jeffrey H. Schwartz Department of Anthropology University of Pittsburgh Pittsburgh, Pennsylvania

Ian Tattersall Department of Anthropology American Museum of Natural History New York, New York

(\|/)WILEY-LISS A JOHN WILEY &, SONS, INC., PUBLICATION

tVlus^um National d'llis'olre Nature Mparterrieiitd* Pr6histoire 1, ruo Ftrn6 Panlwd 75013 PARIS

This book is printed on acid-free paper. © Copyright © 2005, text by Jeffrey 11. Schwartz and Ian Tatlersall; illustrations and photographs by Jeffrey 11. Schwartz (with exception* a» noted in the Preface). All rights reserved. Published by John Wiley &, Sons, Inc., I loboken, New Jersey, Published simultaneously in Canada. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to (he Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, 978-750-8-100, ^x 978-6468600, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department,John Wiley ck.Sons, Inc., I l l River Street, I loboken, NJ 07030, (201) 7486011, fix (201) 74S-6008. Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. The publisher and the author make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of fitness for a particular purpose. This work is sold with the understanding that the publisher is not engaged in rendering professional services. The advice and strategics contained herein may not be suitable for every situation. In view of ongoing research, equipment modifications, changes in governmental regulations, and the constant flow of information relating to the use of experimental reagents, equipment, and devices, the reader is urged to review and evaluate the information provided in the package insert or instructions for each chemical, piece of equipment, reagent, or device for, among other things, any changes in the instructions or indication of usage and for added warnings and precautions. The fact that an organization or Website is referred to in this work as a citation and/or a potential source of further information does not mean that the author or the publisher endorses the information the organization or Website may provide or recommendations it may make. Further, readers should be aware that Internet Websites listed in this work may have changed or disappeared between when this work was written and when it is read. No warranty may be created or extended by any promotional statements for this work. Neither the publisher nor the author shall be liable for any damages arising herefrom. For general information on our other products and services please contact our Customer Care Department within the U.S. at 877-762-2974, outside the U.S. at 317-572-3993 or fax 317-572-4002. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print, however, may not be available in electronic format. Library of Congress Cataloging-in-Publication Data is available. 0-471-31929-5

Printed in the United States of America. 10

9 8 7 6 5 4 3 2 1

To

*'i\

i?/7# Markus

>""•.

r

.' v

'

• ' •

•('

• ' • ' • » ,

'«.>?•:*.•.;• v v »

- i ••.•

. s.-

. • - . .

•

( i \ : . •'. \ '

'•'.

y

J

-•»••

•*•

/

' *i

v ,;./•',

."

.'•; > * ""•

'„

*•»"

- • -V--..' *

•

••

I r:yr--]\-'--\:y~--::;

Preface

CONTENTS

ix

Lothagam Lukeino Maka Makapansgat Male ma Olduvai Gorge Omo Valley, Lower (Shungura, Usno) Peninj (Lake Natron) Stcrkfontein Swartkrans Tabarin (Tugen Hills) Taung (Taungs) Turkana, West (Lomckwi, Lokalalei, Nachukui)

PARTI. INTRODUCTION Descriptive Protocol Descriptive Format Anatomical Terminology Figures Abbreviations Maps Layout of En tries

3 3 4 13 14 18

PART 2. SITE ENTRIES Allia Bay Belohdclie Chcsowanja Drimolen Fejej Hadar Kanapoi Koobi Fora (East Turkana, East Rudolf) Kromdraai Laetoli (Laetolil, Garusi)

23 30 33 37 48 50 118

200 202 209 219 243 245 254 294 298 374 437 439 448

PART 3. HOMINID CRANIODENTAL MORPHOLOGIES: A N OVERVIEW

Introduction Systematic Approach to the Hominid Fossil Record The Family Hominidae and the Earliest Ho mini ds

141 166 182

vii

465 466 467

CONTENTS

VIII

Operational Problems in the Alpha Taxonomy of the "Early Hominids"

471

Thc'Australopiths" Southern Africa Eastern Africa: The "Robusts" Other Australopiths" Australopithecus anam ens is Australopithecus afarensis "Early Homo"

473 473 479 482 482 483 486

The Ubiquitous Homo erectus: Species or

490

Grab-Bag? Homo erectus and Its Putative Relatives 490 in Java Putative Homo erectus in China 493 Putative Homo erectus from Africa 494

Putative Homo erectus from Europe

493

Middle and Late Pleistocene Hominids of Europe

500

Early Middle Pleistocene Hominids Homo heidelbergensis and Its Putative Relatives

500 502

T h e Neanderthals and Related Forms

504

Homo sapiens and "Archaic Homo sapiens" 506 Homo sapiens and Suggested 507 Close Relatives Other Members of the "Archaic 508 Homo sapiens" Group from the Levant and Africa Coda Appendix

510 552

PREFACE

This is the fourth volume in a series dedicated to the standardized description and illustration of the principal fossil specimens that document the hominid biological past. O u r hope is that these volumes will provide a comparative resource that may be used by those many interested individuals who lack the time and/or resources to examine first-hand the swelline number of original fossils that document the long story ot hominid evolution. The first two volumes, authored by us, are devoted to skulls and dentitions that have been allocated to the genus Homo (Volume 1 covers Europe, and Volume 2 Africa and Asia); the third volume, by Ralph Holloway, Doug Broadfield and Michael Yuan, discusses cranial endocasts; and in this tourth volume we describe African craniodental remains that have been attributed to the genera Australopithecus^ Paranthropas and Orrorin.

possible to sort out the species-level variety of hominids to general satisfaction, it will be premature to proceed to higher-level analyses. We do, however, provide at the end of this fourth volume a general survey of the morphologies we have encountered in the compilation of our three craniodental volumes, and we note some of the implications of those morphologies. Another regret is the absence from this resource of several early hominid or putatively hominid genera such as the recendy named Sahelanthropns> Kenyanthropus and Ardipithecits\ but we hope to be able to include them in future contributions to this series. We begin this volume with an abbreviated account of our descriptive protocol (for a more comprehensive treatment of this subject, the reader is referred to Volume 1 of this series). As in earlier volumes, the entries are organized alphabetically by site; and to the morphological descriptions are added details ot discover}*, dating, archaeological context and so forth. Description remains paramount, however. As before, where morphological variety seems to dictate we have grouped fossils from a single site into various morphs. In this volume, particularly, many of these morph groupings will be unfamiliar, and many are necessarily tentative. We have thus been careful to describe as many individual fossils as possible, and the reader should be able to locate these individual descriptions

As our work on the series progressed, it became clear that we would have to stop short of our original goal ot concluding this fourth volume with a general survey of hominid systematics and phylogenetic relationships. For although we fully recognize that not all morphs represent their own species, the diversity of morphologies we unearthed in the process of making detailed descriptions of so many fossils makes it clear that it is too soon to claim even that a rational alpha taxonomy of fossil hominids is in sight. Until it is IX

X

PUKFACE

readily, even where the order of listing is perhaps unexpected. Clearly, the definitive account of the human fossil record will never be written. Partly this is for the best of reasons: the paleoanthropological record is already very extensive, and it is growing at a rate with which it is hard to keep up. Partly, though, it reflects the fact that certain human fossils, even ones that have been comprehensively published, arc surrounded by a wall of protectionism that constitutes a major stumbling block in what is after all a comparative science. Thus, for example, the type materials of two proposed species of Australopithecus, named and described in leading scientific journals several years ago, remain at this writing off-limits to the general paleoanthropological community (and absent from this volume) due to their describcrs* steadfast resistance to any independent verification. These are the species Australopithecus garhi and Australopithecus bahrelghazali, and they are joined by described specimens (e.g., the Konso cranium) that are alleged to extend significantly the morphological ranges of their species (in that particular case, Paranthropus boisei), but that are likewise unavailable for general examination. T h e prevailing problems of access to published type materials run directly counter not only to the spirit but to the letter of the International Code of Zoological Nomenclature, in which (4th edition, 1999) Paragraph 72.10 states that "Holotypes, syntypes, lectotypes and neotypes . . . . are to be held in trust for science by the persons responsible for their safe-keeping (p. 79)". T h e associated Recommendation 72F adds that "Every institution in which name-bearing types are deposited should . . . make them accessible for study" (p. 79). 1 his stricture applies, of course, not only to institutions but also to those who influence their policies. Until access to published type and associated specim e n h permitted to researchers outside the closed dec-aibing cliques, the species based on them must perforce be regarded by the majority of us as hypothetical constructs, equivalent to such entities as Hseckel*s "Pithecanthropus alalus." These remarks having reluctantly been made, it is gratifying to acknowledge the extraordinary assistance and hospitality extended to us by the great majority of those responsible for the care of the fossils that make up the human biological record. Without the active help of many colleagues this project would never have been possible, and warm welcomes and exceptional kindness all over the world have transformed a potentially

Herculean labor into a pleasure. For this fourth volum we extend our warmest thanks and appreciation lto ti ° u r~n : i._ ... ^ .. tile following, who gave us access to fossils °r provided other valuable help: Tim Bromagc, Ron Clark Nicholas Conard, Eric Delson, Heidi Fouric, Eustace Gitonga, Miriam Haidlc, Andrew Hill, p. Clark Howell, Ato Jara Hailc Mariam, Yusuf Juwaycyi Donatius Kamamba, Teresa Kearney, Kebedc Workc' Andre Keyscr, Bill ICimbel, Beverly Kramer, Kathy Kuman, Kevin Kuykcndall, Mcavc Leakey, Nasser Richard MalitJ o h n Maringah, Mamitu Yilma, Michael Mbago, Emma Mbua, Jacopo Moggi-Cecchi, C. S. Msuya', Charles Musiba, H. M. Nguli, Martin Pickford', Stcphany Potze, Yocl Rak, Issa Ramadhan, Fricdcmann Schrcnk, Horst Scidler, Brigittc Scnut, Francis Thackeray, Phillip Tobias, Alan Walker and Tim White (Maka and Bclohdelic). Wc would also like to take this opportunity to thank Harry Widianto of the Archaeological Service in Yogyakarta, and Mr. Himawan of the Museum Mpu Tantular in Surabaya, for access to Sangiran and Ngawi fossils described in Volume 2. The institutions in which the fossils described here reside, and whose official cooperation was obviously essential, are listed individually by site entry. Wc arc more than grateful to all of them, and thank them for permission to publish photographs of specimens in their care. Photographs of fossils from the Kenya National Museums and the National Museum of Ethiopia arc copyright of those institutions, and the image of Gran Dolina ATD6-5 is © Javier Trucba. Ken Mowbray kindly took the image of the Zhoukoudian reconstruction. All other photographs arc copyright © Jeffrey H . Schwartz. We thank Tim D. Smith for the black-and-white drawings, and Ken Mowbray for the maps. Many other friends and colleagues have also been indispensable in making these volumes a reality. Our initial editor at Wiley, Robert Harington, enthusiastically embraced the notion of this scries, which could not have come to fruition without the commitment or Luna Han and Thorn Moore, who steered it through to completion. Also at Wiley, numerous individuals at all stages of production and marketing deserve our warmest appreciation, particularly Kristin Cooke Fasano, who oversaw production. At the American Museum of Natural I listory Ken Mowbray and Shara Bailey rendered valuable help. At the University o( Pittsburgh, Michelle Ray, first at Photographic Services, and later independently, undertook the painstaking task of scanning all the black-and-white negatives and enhancing each image to bring out a>

PRE 'ACE

Xi

%

much detail as possible. She also compiled the comparative plates in the concluding discussion, with exacting attention to detail. To all of these individuals we offer our warmest thanks. In addition to our personal financial contributions, support for this work was provided by funds administered through the Department of Anthropology of the American Museum of Natural History, as well as by grants from the L. S. B. Leakey Foundation, John Wiley & Sons, Ncvraumont Publishing Co., and, at the University of Pittsburgh, the Central Research Development Fund, the University Center for International Study, and the Nationality Rooms Programs (J. G. Bowman). Finally, it should be noted that no palcoanthropologists embarking on a project such as this one could ever ignore the fact that they are standing on the shoulders of some very illustrious predecessors. Notable among these forerunners are the authors and editors of the Catalogue des Hommes Fossiles,

edited by H. V. Vallois and H. L. Movius and published in 1953; the three volumes of the Catalogue of Fossil Hominids, edited by K. P. Oakley, B. G. Campbell and T. I. Molleson, and published and revised between 1967 and 1977; and M. H. Day's multicdition Guide to Fossil Man, which first appeared in 1965. New information relevant to these catalogues is available via the invaluable series Horn in id Remains: An Up-Date, edited on an ongoing basis by R. Orban, P. Semal and colleagues. None of these works has or had exactly the same intentions as this one; for example, the Catalogue of Fossil Hominids aimed at comprehensiveness of sites but ignored morphology and illustration, whereas the Guide to Fossil Man did provide some general morphological information and illustration but was more selective in site choice. Nevertheless, we are keenly aware that we are following a road that has already been partly trodden, and that our task has thereby been rendered easier.

PART

ONE

INTRODUCTION

Murium fh!inn ,1 t'Bztme Haturelle L.»<*f.Si1erT.yiit cV, f-rohistoire 75013 PARIS

1 INTHODUCTION

3

DESCRIPTIVE PROTOCOL In this volume wc describe as many as possible of the major fossils that make up the records of the genera Australopithecus, Paranthropus and Orrorin. The arrangement is alphabetical by site: wc describe each fossil or fossil assemblage individually, and without reference to specimens from other sites. To make this possible we have adopted a single descriptive protocol and a uniform nomenclature for morphological features of the hominid skull. Armed with these descriptions, the reader will be able to make direct comparisons among whatever fossils he or she desires. In the following: secrion, we present the descriptive format that we have developed and, where necessary, we discuss details of nomenclature. Fuller presentations may be found in Volume 1 and in the new Figures 1—8 in this section. Each fossil description in these volumes follows the anatomical order presented below, even where individual specimens are incomplete. The descriptions in each entry are grouped by morph; but given the manifold difficulties we have experienced in determining morph boundaries, many of which we regard as provisional, all major specimens have been described individually so that their descriptions can readily be recovered even should their morph assignments change.

In the following outline of our descriptive protocol, we highlight the principal bones and structures to which attention is paid, region by anatomical region; necessarily, there is some overlap between descriptions of adjacent regions and structures. For nomenclature, refer also to Figures 1-8. Wc hope that readers will not be excessively disappointed by the absence of measurements (except for cranial capacities where available) of the specimens described. Partly this was to save space in an already very bulky scries of books, partly it was because measurement criteria vary so much among practitioners, and partly it was because in our view measurements often deflect attention away from the smaller details of morphology—which are our principal preoccupation here, and which are often of especial significance in a group as close-knit as Hominidae. Size does, of course, matter, and wc hope that the fact that all photographs in standard views bear scales will provide the reader with an adequate general guide to the size of each fossil. Direct measurements will, of course, also be found in many of the works we cite in the "Previous Descriptions and Analyses" section of each entry.

DESCRIPTIVE FORMAT Following is a summary of the protocol and sequence that we follow wherever possible in describing hominid craniodental fossils. A fuller account is provided in Volume 1; terminology is clarified and summarized in Figures 1 - 8 . General Comments: State of preservation and completeness of the specimen(s). Cranium—Overview: Overall form and proportions of the cranium; general bone thickness. Supraorbital Region and Splanchnocranium (Figures 1-3): Supraorbital structures, glabella, frontal sinuses, orbits, infraorbital region and zygomas; nasal bones, aperture and cavity; nasoalveolar region, palate and pterygoids.

Cranial Roof (Figures 1 and 2): Contours and external details of frontal and parictals. Cranial Walls (Figure 2): Temporal bone and attendant fossae; posterior part of zygomatic arch; lateral mastoid region and auditory meatus; sutural configurations. Cranial Rear (Figure 3): General contour, occipital plane and associated structures. Cranial Base (Figure 4): Nuchal plane including the contiguous mastoid area; external petrosal and associated processes and foramina; spheno- and basioccipital region; foramen magnum and occipital condyles; mandibular fossa.

4

INTRODUCTION

Cranial Sutures andThickncss: Nature ofthc sutural margins; thickness of cranial bone, especially of the parictals and occipital. Anterior Endocranial Compartment (Figure 5): Anterior cranial fossa and associated structures. Middle Endocranial Compartment (Figure 5): Middle cranial fossa and associated structures, including petrosals. Posterior Endocranial Compartment (Figure 5): Posterior cranial fossa and associated structures, excluding petrosals.

Major Endocranial Sinus Impressions (Figur ^ Mandible (Figure 6): Overview and A f morphology. ^N Dentition—Overview: Condition, general sire proportions. ^ Upper Dentition (Figure 7): By tooth, mesial to distal Major points of variation among the perman teeth are discussed below; descriptions of decidT ous teeth, where known, follow the same protocol Lower Dentition (Figure 8): By tooth, mesial to distal, as above.

ANATOMICAL TERMINOLOGY FIGURES

sagittal crest

postglabellar plane

supraorbital margin/ torus zygomatic process of frontal

frontonasal suture

zygomaticofrontal suture frontal process of zygoma

zygomaticofacial foramina

zygomatic arch lateral crest (margin) of nasal aperture

zygomaticofacial suture facial 'pillar

infraorbital foramen facial "pillar" inferior nasal "hammocking" alveolar crest/ margin anterior nasal spine

Figure 1. Front view of cranium, identifying the various features discussed in the text.

I NTKODUCT ION

temporal lines

bregma

frontal rise

lambda

supraglabellar plane

parietal notch

glabella

lacrimal fossa asterion

anterior root of zygomatic arch

occipital torus

nasoalveolar clivus

occipitomastoid suture

mastoid region/ process auditory meatus articular

tubercle

diastema zygomaticotemporal suture

facial "pillar"

Figure 2. Lateral view of cranium, identifying the various features discussed in the text, articular f - articular fossa

INTRODUCTION

sagittal crest lambda sagittal suture

A

\ ^w

lambdoidal suture \ squamosal suture ~—^

zygomatic arch

/

parietal

W

squamosa! (temporal)

f

/

X

panetai

"

^

posterior root of * zygomatic arch

•astenoo

• ocdfHtomaslod suture mastoid region mastoid notch

superior nuchal line/crest

occipital plane

nuchal plane

external occipital protuberance

Figure 3 . Rear view of cranium, identifying the various features discussed in the text.

INTKODUCTION

incisive foramen

transverse palatine suture

greater palatine foramen lesser palatine foramen

hamulus

posterior nasal spine lateral pterygoid plate medial pterygoid plate temporal fossa — .

i region of articular eminence

^ foramen ovale foramen lacerum pseudostyloid process (broken)

articular fossa postglenoid plate

basioccipital ectotympanic tube petrosal auditory meatus

foramen spinosum notch in basioccipital occipital condyle

carotid canal

foramen magnum

mastoid process styloid pit stylomastoid foramen external occipital crest

mastoid notch

nuc.hal p' jne occipitomastoid suture

inferior nuchal crest/iine

Waldeyer's crest

Figure 4. Basal view of cranium, identifying the various features discussed in the '<:>:(

I N I KilHUi! THIN

frontal crest

sphenofrontal suture

lessor wing or sphenoid

crista gall) cribriform plate

superior orbital fissure

optic foramen

optic groove

foramen rotundum * groove for anterior division of middle meningeal a,

tuberculum sollae hypophyseal fossa

foremen ovate

dorsum sollae foramen splnosum posterior cllnoid process

groovo for posterior division of middle meningeal a. superior petrosal sinus

foramen lacorum

region of arcuate eminence Internal auditory meatus

jugular foramen

subarcuate fossa

sub-subarcuate fossa occipital sinus

sigmoid sinus

occipitomastoid suture accessory sinus Internal occipital protuberance

Figure 5. Internal view of cranium, identifying the various features discussed in the text.

9

I N T It O II U C T I O N

postmcisal plane head/condyle

sigmoid notch

coronoid process

mandibular gutter ramus c corono»d process

/ sigmoid notch crest

symphyseal region

gonial angle mental foramen corpus head/condyle 'coronoid digastric fossae

P " ? r region of lingula inferior margin mandibular foramen

mylohyoid fissure gonial angle

medial pterygoid tubercle internal alveolar crest mylohyoid line submandibular fossa postihcisal Diane

Figure 6. Views of mandibles, identifying the various features discussed in the text.

INTRODUCTION

10

parastyle

paracone

precingulum

preprotocrista

{

postprotocrista

paracone

metacone

postcingulum

hypocone

Figure 7. Views of upper dentition, identifying the various features discussed in the

text.

11

INTRODUCTION

mesial margocrista

distal margocrista

lingual pillar

anterior fovea

lingual tubercle

protostylar region

protocone

hypocone parastylar region

metaconule

Figure 7.

( Continued).

INTRODUCTION

12

mesial margocristid distal margocristid

anterior fovea lingual tubercle

. M

. <2

protoconid

metaconid posterior fovea postcingufid

metaconid

paraconkj shelf (paracnslid)

entoconkj

metastylid

Figure 8. View of lower dentition, identifying the various features discussed in the text.

INTRODUCTION

13

ABBREVIATIONS In order to saw space, we haw abbreviated certain frequently occurring terms. We use R and L for right and left, "respectively; a/p for anteroposterior, and s/i for supercnnferior. Specifically for tooth descriptions, m, d, b and 1 stand for mesial, distal, buccal and linjrual,respectively,and we combine these signifies to indicate direction, e.g., m/b = mesiobuccal(ly). We use standard terminology for denoting teeth, e.g., l2

for the lower lateral incisors, and M l for the first upper molars; we also use PI and P2 for the anterior and posterior premolars, in preference to the alternative P3 and P4. Super- and subscripts (I2, M l ) are only used where potential ambiguity exists as to whether the teeth concerned are upper or lower. As concerns dates, we use the abbreviations Ma for millions of years (ago), and Ka for thousands of years (ago).

14

INTRODUCTION

MAPS All sites catalogued in Part 2 of this volume are shown in Maps 1 (Ethiopia), 2 (Kenya), 3 (Tanzania and Malawi) and 4 (South Africa). These maps are

grouped in a single section to make individual sites easy as possible to find.

Figure 9. Map to show the location of Ethiopian early hominid fossil sites covered in this volume site entries.

15

INTRODUCTION

KENYA

S U D A N

•: \ j 3

E T H I O P I A

0

60

ii

ii

i

0

100

195 Kms

^^"^

^

^

A

J

Kana

P°i#

o I

r

\

\

y 1

/ >^»—"

)

•NAIROBI

/

I N D I A N

1

^^t

OCEAN

J ••

. •/'. -v'-;." : --'-" ; " ; ": •'-'/•• ' ": , '.; v ' ;: ' : .v

/

K E N Y A

^v

TANZANIA

/

i

^ t


I

1 Lukeino* ,. , . / •Tabarin A 1 \ •Chesowanja pns^S V/W Kapthurin# \ y 1P^> LakeBaringo

[Lake Victoria

^

V

I

V ^ S \ _ Lothagam# V p ^ LakeTurkana

\

/

/

\ (Nuiia Bay

UGANDA

'

V; "\_

A West Turkana'0 y\ Koobi F o r a \

120 Miles

V_^

" • " •

••/..'"•v',''

."''.

•'

•

i

•

' : . ' • . . ' . ' '. '"' • > ; . ' \

figure 10. Map to show the location of Kenyan early hominid fossil sites covered in this volume site entries.

16

INTRODUCTION

TANZANIA AND MALAWI

UGANDA

175 200

Luke Victoria

&

Z A I R E

K

r

Gorge* , \ • Laetoli

350Mile&| 570 Km*

N • Arusha

j

INDIAN OCEAN

T A N Z A N I A DAR ES i SALAAM

Malema«

(

)

/ *» J

-:• / ^

Z A M B 1A

• LUSAKA)

j

! <>

"'LILONGWE

j /^ |

\

a



i \

Z I M B A B W E Figure 11. Map to show the location of Tanzanian and Malawi early hominid fossil sites covered in this section si entries.

17

INTRODUCTION

SOUTH AFRICA 200

400 Miles 640 Kms

320

B O T S W A N A

< N

• Makapansgat Drimolen \ .PRETORIA Sterkfontein\ K r 0 m d r a a j Swartkrans- •

N A M I B I A

O 2

JOHANNESBURG

1, Taung

S O U T H

A F R I C A

SOUTH ATLANTIC OCEAN

INDIAN OCEAN

Figure 12. Map to show the location of South African early hominid fossil sites covered in this section site

18

I NTItODUCTION

LAYOUT OF ENTRIES Early hominid sites, in this volume all in Africa, are presented in alphabetical order. The name of a site first given is that by which it is most commonly known; any alternative or complementary names follow in parentheses. Within each site entry, information is presented in the following categories: Location. Where the site is: country, region and in most cases, distance and direction to nearest village and/or major town. Also consult "Maps" section. Discovery. Datc(s) of discover}' of the fossil(s), plus the name of the individual(s) who made the discovcry(ics), or the name of the excavation directors). Note that the dates given arc not those of the discover)' of the sites themselves, and the names arc not necessarily those of the discoverers of the sites. Material. A short note on what the relevant fossil(s) from the site consist(s) of. Further details are found in the "Morphology" section. Dating and Stratigraphic Context. A brief review of absolute dates (if any) obtained for the site and/or hominids, and of the stratigraphic context(s), geological or archaeological, of the locality(ics) of fossil recover}'. Archaeological Context. A brief resume of the cultural association(s) (if any) of the hominid fossil(s). Where there is none, this section is omitted. Previous Descriptions and Analyses. An overview of the history of description and analysis of the fossil(s). This is not intended to be comprehensive or discursive, but is simply a very general summary and pointer toward the literature. Morphology. Here we come to the meat of the volume. We present a brief but comprehensive account of the morphology of cranial, mandibular and dental fossil(s) of Australopithecus, Paranthropus or Onorin known from each site. These accounts arc based on the approach to terminology and description that was presented in Volume 1 of this series, and is thus made according to a consistent protocol that makes descriptions directly and conveniently comparable from one specimen to

another and from one site to the next. Where the hominid remains consist of scries of fragments we describe as complete a composite as representation allows. Where there is no question as to the homogeneity of the sample, our description is based on the best-preserved specimen from cadi site, with references added to any less wellpreserved fossils in which morphology differs significantly. If more than one distinctive morpli (as opposed to simple character variation) appears to us to be represented at a site, we list and describe specimens belonging to each morph individually, using the same protocol. The morphs we recognize may or may not correspond to the morphological or systematic units noted in the literature surveys. Above all in this volume, in those many cases where morph recognition is difficult or provisional, we have provided individual descriptions of all major specimens so that readers can verify morph allocations and arrive at independent judgments on the morphs we have have designated. Where the morphs we present depart from the familiar, we invite readers to pay particular attention to the morphologies that distinguish them, for the level of detail is often closer than has been the paleoanthropological standard. Generally, the best example of a morph is described first, and the rest follow (where possible) in numerical order by catalogue number. In this volume, especially, many of the morphs wc delineate are dental, and the well-known vagaries of dental wear frequently make morph assignment of particular specimens difficult or impossible. Hence many specimens have had to be designated as "unassignable to morph." Where both adult and juvenile specimens are known, these arc described separately, as in some cases, arc all specimens from a particular site. Whilst wc note, in the case of multiple morphs, which fossils belong to which morph, we make no attempt at systematic analysis in this section, and wc do not normally attempt to compare any of the fossil(s) under description with any others beyond those from the same site and belonging to the same morph, though we do note which morphs arc represented at multiple sites. Thus the central

I NTHODUCT I ON

focus is strictly on the morphology of individual fossils, described by way of the protocol described in detail in Volume 1. This allows the reader to make objective comparisons among fossils from every site in this scries of books, unimpeded by confusing comparatives. Even where morph assignments arc unfamiliar, the numerical-order listings should make it relatively easy nonetheless to locate the descriptions of individual fossils. It is important while reading the descriptions and dis-

19

cussion to bear in mind that our concept of morph lies as a level that might be described as "prc-alpha taxonomy" (Schwartz, in press). References. For the reader's convenience, all literature references made in previous sections of each site entry arc quoted in full here. Note that this is not, and is not intended to be, a comprehensive bibliography on each site and the fossils found there. Repository. The location where the fossils are held.

PAR TIT W O

SITE ENTRIES .

* •

.

- «

: ' •

-./ •' -• i

."

».,'

•••

v

•;'

.' • ' ; *

i.

• *

• •• •

"V

:"-;<. " '

r

— ^

.-•

-'V

.'

ALLIA BAY

LOCATION Fossiliferous outcrops within Area 261 on the eastern margin of Lake Turkana in northern Kenva, just south of the main Koobi Fora collecting area (S lap 2).

and Walker (2001) summarize paleoenvironmental work in the area that suggests a habitat rather like that of Hadan fairly well wooded, with some moderately open bushland and woodland, and plenty of water.

DlSCO\XRY First hominid molar found by J. Kithumbi in 1982 (Leake}- and Walker, 1985); other hominid remains found subsequently over several years to 1997.

PREVIOUS DESCRIPTIONS AND ANALYSES In 19S5 R. E. F. Leakey and Walker (19S5) described an isolated molar crown from Allia Bay, but without attributing it to any species. This specimen was redescribed by Coffing et al. in 1994, along with twelve others (mostly also isolated teeth) that had been found at Allia Bay between 19S2 and 1994. These authors regarded all thirteen specimens as hominids most closely resembling A. afarensis. In the following year these same fossils were ascribed by M. G. Leakey et al. (1995) to the new species Australopithecus anamensis, the slightly older type material of which comes from the site of Kanapoi, some distance to the south of the current Lake Turkana but still within the Turkana Basin. In a comment published concurrendy, Andrews (1995) suggested that the Allia Bay fossils resembled later specimens in the Kanapoi assemblage in being "hominine with Homo-Ukc postcrania" (p. 556), while earlier Kanapoi specimens in contrast represented a "thick-enamelled hominine with jaws like fossil apes" (p. 556). Subsequendy it was shown (Leakey et al., 1998) that the time spread at Kanapoi was smaller than had earlier been supposed. These authors continued to assign all Kanapoi and Allia Bay hominids to A. anamensis, and added a further dozen

MATERIAL Some 31 hominid specimens, mostly isolated teeth but including some maxillary and mandibular frasments and a radius, are listed from Area 261 by Ward, Leake)-and Walker (2001). DATING AND STRATIGRAPHIC CONTEXT The principally fluviatile sediments of the Koobi Fora Formation in Area 261 are interspersed with tuffs. The bone-bearing level of the 261-1 site from which almost all of the Allia Bay fossil hominids are derived lies stratigraphically about 5 m below the Moiti tuff, which is dated in other localities to about 3.9 Ma. A date of 3.95 Ma has thus been extrapolated for the bulk of the fossils (Brown and Feibel, 1991; Ward, Leakey and Walker, 1999), though three specimens were found in an infill within the Moiti Tuff and are thus fractionally younger than the Tuff itself. The radius comes from the nearby Sibilot locality that is dated to 3.9 Ma (Heinrich et al., 1993). Ward, Leakey

23

24

SITE

or so specimens to the list of those from Allia Bay. Most recently. Ward et ai. (2001) reappraised the M i a Bav sample, and at least provisionally maintained the conclusion that both the Alia Bay and Kanapoi assemblages represent only the single bipedal species A. anamensis. In their view, this species most closely resembles A. afarensis among other hominids known, though differing from the latter in dental and racial features they regarded as primitive. They detected "no apomorphies precluding A. anjmtnsis trom the ancestry ot'A. afirerzsis* (Ward et al„ 2001: 255). MORPHOLOGY .Although this is a relatively small sample, sufficient differences exist among groups ot specimens to warrant the delineation of several morphs, two ot which appear to match with specimens trom Kanapoi. One of these matches is with the type material ot A. anamensis from the latter site. Two upper molars are similar morphologically to the preserved upper molar in the Homo cranium KNM-ER 3733, and a fourth morph is exemplified by the maxilla ER 30745. KNM-ER 30745 Morph (includes ER 20420,20427, 24149,30200A) KSSt-ER 30745. Heavily reconstructed L partial maxilla with partial alveoli for anterior teeth; crowns are glued in the broken C, P I and P2, slightly broken M l , very broken M2, and partly broken M 3 . Palate is very shallow, deepest at M 3 and becoming considerably shallower anteriorly. R and L incisive fossae lie well back in the nasal cavity, while the large, forwardly angled palatal opening (i.e., a single incisive foramen) is level with P I . Judging from the alveoli, 1 1 - 2 roots were not compressed. C root was quite robust. The glued-in partial C crown suggests it was not a very large tooth. P I and P2 arc weathered, but are still relatively large teeth; PI is as long m/d as P2 across the lingual side, slightly longer across the midline, and much longer across the buccal side. P 1 - P 2 paracone and protocone are situated quite far apart. T h e buccal sides of both Ps are strongly swollen, while the lingual sides are straighten PI has distinct parastylar and metastylar corners, and a distinct anterior and a larger posterior fovea. PI protocone is slightly mesiallv shifted and not as tall as the centrally situated paracone; the buccal and lingual sides of the tooth are subequal in m/d length. The buccal side of the P2 is noticeably shorter m/d than the lingual side (i.e., the

ENTRIES

tooth narrows buccafly). T h e VI paracone and S» protocone opposite it are slightly mesiallv position-.;, the paracone is not much taller than the protocor T h e anterior fovea is small; the posterior is sl™*»ri» larger. T h e somewhat worn M i is subscruore" ITV* swollen d/l by a thick postcingulum that encloses i moderate basin as it arcs out and up from a Lir^ hypocone to fade out on the distal side of the tnetacone. T h e meraconc is slightly smaller than die mesiallv placed paracone. and both buccal cusps are somewhat peripherally positioned. T h e hvpoconc lies slightly distal to the metacone, and is separated trom the mesiallv and not very internally placed protocone by a distinct lingual, wedge-shaped notch. "The metacone and protocone latter two cusps are equailv distended lingually. There appears to be a short but stout postprotocrista (or at least a metaconule) between the bases ot the protocone and metacone. There also appears to be a short precingulum that is separated from the mesial side of the paracone by a small fovea. The lingual side of the tooth bulges slightly. Two protostvlar pits are present just on the mesial side of the protocone. M 2 is broken; a protostylar pit lies mesiallv. T h e preserved portions of protocone and hypocone are similar in configuration to their counterparts on the M l , including in the notch that lies between them. M 3 (broken in the region of the paracone) has a similar protostylar pit. Its distal side is rounded, with some evidence of cuspulation. The protocone is very mesiallv and peripherally placed; the hypocone is smaller and lies close to it. There is a planar surface that emerges distolingually from the base ot the hvpoconc and continually expands to occupy the region of the metacone and paracone. Since this tooth was glued into an incomplete alveolus, it is permissible to ask, since it does not tit into a size/shape gradient with the other molars, whether it belongs to the specimen (or even if it is hominid at all). All molars arc occlusally worn, with shallow vertical lingual grooves.

KNM-ER 30200A. Partial L maxilla with M l - ^ slightly worn. T h e palate had sloping sides. Both molars have a mesial protostylar pit, a precingulum that enclosed a narrow fovea on the mesial side ot the paracone, a metacone that is slightly smaller than the paracone, peripherally placed and somcwlu compressed buccal cusps, mesiallv and periphery . placed protoconcs that are level with the hypocone* lingually, a notch between the protocone a"

AM,iA

hxpocone that lie* Oightly dUul to (he metacone, and pi-oh.iblv a *hort poMprotocrista or mctaconulc Ix'iwven lho IHOCS of the mcl.uonc and protocone. lloth ate vwollcu
KSM 1R 20420. Probably L \ 1 ; broken, worn; cf. 30745. KX.U-I'R 20427, Unempted M* crown. This tooth is tiny, very long m/d, swollen d/1. It has a mesial pn>tost\lar pit ami only slightly internally placed lingual cusps; cf. 30200A. k'SMER 24149, Upper P fragment; cf. 30745. Possible KNM-ER 3733 Morph (see Koobi Fora, in Volume 2 of this scries; includes ER 20421,30200B) KXMER 20421. A rather small and slightly worn upper R molariform; probably a dm 2 (although it might be an M:'). The crown is somewhat cuspulated and is greatly distended d/1 by a very short postcingulum that emerges from the large hypoconc and terminates near the buccal margin of the mctaconc, enclosing a deep, but small to moderate basin. A large conulc lies in the postcingulum that swings around the isolated hypoconc. A long prccingulum that encloses a large and deep basin courses trom the somewhat internally placed apex of the very large protocone, and swings briefly mesially before going straight up the side of the tooth and then cornering into the apex of the mesially placed paracone. There is a thick, obliquely oriented pillar along the internal face of the paracone that goes from the mesial apex of the cusp toward the center of the large, deep trigon basin; this pillar produces a paracone that looks compressed internally with a m/b tacing apex. In contrast the metacone, which lies somewhat lingual to the paracone and whose apex races more directly downward, appears relatively bulbous. The rvypocone, which is much smaller than the protocone (from which it is only partially separated by a thin groove), lies more or less opposite the subequal metacone. The hvpocone does not extend lingually as far as the protocone, and thus the lingual side of the tooth is oblique. There is a long lingual slope to the crown. A shallow protostylar pit lies on the mesial side of the protocone, well buccal to the lingual side of the cusp. There is a small

25

IIAv

tnctaconulc between the bancs of the protocone and metacone. In overall shape as well as detailed morphology, this tooth is very similar to the only preserved tooth — an M2—in the ER 3733 cranium from Koobi Fora, and can easily be accommodated with it in a shape gradient. KNM-ER 3020011. Partial L upper molariform tooth (possibly dm 2 , although M 1 cannot be ruled out). Preserved is a somewhat cuspulated, tiny isolated hypoconc, around which the postcingulum swings. The postcingulum bears a conulc. K N M - K P 31712 (J, K) Morpli (sec Kanapoi; includes ER 20422,30201) KNM-ER 20422. A tiny Ldm 2 . Generally similar to KP 31712J and K, but differs in being slightly less cuspulated, with a smaller cingulid between the hypoconulid and hypoconid. KNM-ER 30201. A Ldm 2 , similar to but slightly larger than ER 20422; especially similar to KP 31712J

and K. A. anamensis Morph (sec Kanapoi; includes K N M ER 20423,20428,20432A, 30731) KNM-ER 20423. M2 anamensis.

fragment; cf. Kanapoi A.

KNM-ER 20428. L M 3 crown, quite worn. The paracristid courses around the mctaconid; cf. anamensis} KNM-ER 20432A. Fragment of L mandibular corpus with a large antcro-obliquely oriented C root and worn, weathered crowns of P i -2. The corpus was probably quite deep and the symphysis very vertical and more or less flat between the R and LCs. PI was not longer m/d than P2 and was not oriented antcroobliquely; it is quite truncated mesially, with its d/1 part most accentuated. The PI paracristid is short; it emanates from the centrally positioned protoconid and kinks back quite sharply to end at a crease separating it from the base of a crest that descends lingually along the protoconid. This crest runs lingually and then distally around, to end in a stylid lying at the distal base of the protoconid (thereby enclosing a lingually shifted talonid basin). The buccal side of PI is somewhat sloping, with low mesial and distal pillars. The P2 is somewhat wider b/1 and longer m/d than P I . The P2 protoconid and

26

S 1TK KNTHIES

mctaconid are quite mcsially positioned (thus the trigonid basin/anterior fovea is quite small and the talonid basin/posterior fovea quite large). The buccal side is quite sloping and bears low mesial and distal pillars. Resembles the A. anametisis holotypc, KP 29281, in relative P 1 - P 2 shapes.

Uninformativc/Unsccn ^ KNM-ER 20432B. Fragment of corpus; indct minate. KNM-ER 20432C. Fragment of corpus with rooi KNM-ER 24154. Worn molar fragment.

KNM-ER 30731. R lower C; worn. Buccal pillars and cingulid are anamensis-Wkc. A distal margocristid contributes to a heel. The mesial margocristid is rather vertically oriented. Unassignable to Morph KNM-ER 7727. An isolated crown, probably of a LM ; somewhat worn and weathered. The tooth is very wide b/1 and shorter m/d, the buccal side shorter than the lingual side. The mesial and especially distal sides of the tooth curve away from the extraordinarily internally placed, indistinct and almost unelevated protocone and hypocone. The latter cusp lies almost directly at the base of the rather large metacone, which in turn lies close to the slightly smaller but buccally more bulbous and peripherally placed paracone. The tiny protocone lies opposite this cusp. The trigon basin is fairly deep, but is restricted by the four cusps. The very thick cingulum is more distended lingually around the faces of the protocone and hypocone; it is slightly indented in the region between the cusp bases. It appears that the hypocone cingulum continued distallv around the tooth as a thick postcingulum that fades out on the side of the metacone. The protocone cingulum fades out quickly along the mesial side of the tooth. The buccally emphasized protocone, closely approximated metacone and thick lingual cingulum are reminiscent of an upper molar from Kanapoi, KP 34725G, but the other details clearly distinguish the two teeth as representing different morphs. 1

KNM-ER 24155. Worn molar fragment. KNM-ER 30744. LP 2 . Very worn. KNM-ER 30747. P 2 crown fragment. KNM-ER 3074S, 9. Tooth fragments. KNM-ER 30750. Broken RC,. Small, with a distal lingual pillar bearing a deep groove behind and a shallower depression in front.

KNM-ER 226S3. LP 2 ; worn. The broken single root is large, stout and compressed m/d. The metaconid lies mesially; the trigonid is small, but the slightly lingually placed talonid is not greatly larger. This is not the same P 2 as in ER 20432, which has two roots and a greatly expanded distal moiety. KNM-ER 24148. Fragment of Ldm 2 crown with distinct para- and metaconulcs. Somewhat cuspidated. KNM-ER 30202. Huge RI l ; worn. Crown spatulatc, with low lingual margocristids and central pillar.

\

Figure 1. Top L: KNM-ER 20421. upf? LM; Top R: KNM-ER 7727, upper LM; B o " o t " R KNM-ER 20422, lower Ldm2; Bottom R: KNM^ 20427, lower LMJ (scale = 1 cm).

ALMA BAY

ALLIA

REFERENCES Andrews, P. 1995. Ecological apes and ancestors. Nature 376:555-556. Coffing, K. ct al. 1994. Four-million-ycar-old hominids from East Lake Turkana, Kenya. Am. J. Phys. Antbropol. 93:55-64. Lcakcv, M. G. ct al. 1995. New four-million-ycar-old honiinid species from Kanapoi and Allia Bay, Kenya. Nature 376:565-571. Lcakcv, M. G. et al. 1998. New specimens and confirmation of an early age for Australopithecus anamensis. Nature 393: 62-66.

BAY

27

Leakey, R. E. F. and A. C. Walker. 1985. Further hominids from the Plio-Plcistoccnc of Koobi Fora, Kenva. Am. J. Phys. Anthropol. 67:135-163. Ward, C. V., M. G. Leakey and A. Walker. 1999. The new hominid species Australopithecus anamensis. Evo. Anthropol. 7:197-205. Ward, C. V., M. G. Leakey and A. Walker. 2001. Morphology of Australopithecus anamensis from Kanapoi and Allia Bay, Kenya./ Hum. Evol. 41:255-368. Repository National Museums of Kenya, PO Box 40658, Nairobi, Kenya.

A L L I A BAY F i g u r e 2. K N M - E R 20432, L mandibular fragment (scales = 1 cm).

28

SITE ENTRIES

Figure 3. Top L: KNM-ER 20421, upper R?dm2; Top R: KNM-ER 20428, lower LM3; Bottom L: KNM-ER 20422, lower L dm2; Bottom R: KNMER 30201, lower Ldm2 (scale = 1 cm).

ALUA BAY

Figure 4. KNM-ER 30200A. Partial L maxilla (scale = 1 cm).

ALLIA BAY

ALLIA BAY

Figure 5. Left: KNM-ER 30731, lower LC; Center: KNM-ER 26683, lower LP2; Right: KNM-ER 30202, upper RI1 (scale = 1 cm).

ALLIA BAY

29

Figure 6. KNM-ER 30745, L partial maxilla (scale = 1 cm).

ALLIA BAY

BELOHDELIE

4 Ma thus seems probable, and agrees well with the associated fauna.

LOCATION Collecting area to the east of the Awash River in the Middle Awash Valley of Ethiopia, south of Hadar (Map 1).

PREVIOUS DESCRIPTIONS AND ANALYSES The Belohdelie frontal was reported early on by Clark et al. (1984) and by White (1984). Both referred it simply to Australopithecus, though the latter compared it closely with A. afarensis. The specimen was described at greater length by Asfaw (1987), who noted in it substantial robusticity, beyond the Australopithecus range, as well as various other particularities. However, he concluded that overall it shared most features with A. afarensis, and suggested that it might represent an early member of the species, possibly "close to the morphological divergence point for the hominid and African ape clades" (Asfaw, 1987: 623). In contrast, Kimbel, Johanson and Rak (1994) considered Belohdelie to be good evidence for a species A. afarensis in which long-term stasis was paramount.

DISCOVERY Area first explored in 1975-78 by the Rift Valley Research Mission in Ethiopia, directed by Jon Kalb; hominid locality and frontal fragment found by L. Krishtalka, 1981, during a survey directed by J. D. Clark (Clark et al., 1984).

MATERIAL Partial R frontal (BEL -VP-1/1), with small piece of L parietal; originally found in 7 pieces, 3 adjoining (Clark et al., 1984; Asfaw, 1987).

DATING AND STRATIGRAPHIC C O N T E X T The frontal was a surface find, apparently derived from the Pliocene surface sediments on which it rested. These sediments are reported to lie stratigraphically 11 m below the marker horizon in the Belohdelie Member of the Sagantole Formation known as the Cindery Tuff (Clark et al., 1984). This tuff has been dated by Ar/Ar to 3.85 Ma (Renne et al., 1999). An age for the hominid of a little under

MORPHOLOGY

BEL-VP- 1/1. Various fragments of weathered and mostly thick cranial bone. 1/la, 1/lb, 1/le, and 1/1* are all small, rather uninformative cranial-vault fragments. 1/lc and 1/ld are joined together into a larger piece constituting part of frontal with some or L supraorbital region and small piece of adjoining

30

BKLOUDKLIK

parietal. As reconstructed, the larger piece has a rather angular frontal profile due to fairly sharp join between 1/lc and 1/ld. The bone is moderately thick. Part of the coronal suture is preserved, and indicates that the frontal bone itself was very short a/p. The lateral supraorbital region is represented not quite as far as the zygomaticofrontal suture; not enough is preserved for adequate orientation. The anterior face of the supraorbital region is shorn off; it appears that the lateral part of the supraorbital margin, at least, was only moderately deep s/i, and that the frontal flowed directly from it without any significant posttoral sulcus or plane. The preserved roof of the orbit is moderately concave. T h e temporal ridge is faint; it runs up the lateral margin of the zygomatic process of the frontal and extends some way toward the midline of the orbit before arcing back. Postorbital constriction was pronounced. No internal morphology is preserved. It appears that the anterior part of the anterior cranial fossa curves down more strongly than the outer curve of the frontal.

31

REFERENCES Asfaw, B. 1987. The Belohdclic frontal: new evidence of early hominid cranial morphology from the Afar of Ethiopia./ Hum. Evol. 16:611-624. Clark, J. D. ct al. 1984. Palcoanthropological discoveries in the Middle Awash Valley, Ethiopia. Nature 307:423-428. Kimbcl,W. H., D. C. Johanson and Y. Rak. 1994. The first skull and other new discoveries of Australopithecus afarensis at Hadar, Ethiopia. Nature 368:449-451. Rcnnc, P. R. ct al. 1999. Chronostratigraphv of the Miocene-Pliocene Sagantolc Formation, Middle Awash Valley, Afar rift, Ethiopia. Geo/. Soc. Am. Bull. I l l : 869-885. White, T. D. 1984. Pliocene hominids from the Middle Awash, Ethiopia. Cour. Forsch. Inst. Senckenberg 69: 57-68.

Repository National Museum of Ethiopia, PO Box 76, Addis Ababa, Ethiopia.

SITE ENTRIES

32

BELOHDELIE

Figure 1. NME BEL-VP 1/1, partial frontal (scales = 1 cm).

CHESOWANJA

LOCATION Fossilifcrous exposures located approximately 1.5 km W of the road from Mukutau to Chemoigut, east of Lake Baringo, in the northern Rift of Kenya (Map 2).

KNM-CH 304, from a site about 1 km away, appear to be of similar age (Gowlctt ct al., 1981).

ARCHAEOLOGICAL CONTEXT Chemoigut and Chesowanja sediments have yielded in situ stone artifacts (mostly made in fine-grained lava) of generally Oldowan aspect (the former cf. Karari, the latter cf. Developed Oldowan: Gowlett et al., 1981), but Acheulcan bifaccs from the Chesowanja FM were found on the surface of a channel fill, and thus cannot be regarded as evidence for contemporaneity of Oldowan and Acheulean traditions (see discussion by Gowlett et al., 1981). There is no definitive association of any of the artifacts with a particular kind of hominid. The most unusual aspect of one apparent hominid activity site in the Chemoigut Fm is the presence of numerous small burnt balls of clay that were heated to temperatures comparable to those that arc achieved in simple campfires. Gowlett et al. (1981) conclude that these curious features arc most plausibly explained by hominid activity.

DISCOVERY L. Rungu, during a geological survey conducted by J. Carney, 1970 (facial skeleton); Bernard Ngenco and Wambua Mangao, 1978 (braincase fragments). MATERIAL Partial facial skeleton of adult individual (KNM-CH 1) with RC-M3 (Carney et al., 1971). Also some cranial vault fragments (KNM-CH 303/304), reported by Gowlett etal. (1981). DATING AND STRATIGRAPHIC CONTEXT The geology at Chesowanja was originally reported by Carney et al. (1971) and was extensively refined by various contributors to Bishop (1978). Sediments exposed at Chesowanja belong to the Chemoigut and overlying Chesowanja Formations. The principal stratigraphic marker in this sequence is the Chesowanja Basalt. This lies stratigraphically between the two formations and has been K/Ar dated by Hooker and Miller (1979) to 1.42 Ma. The hominid face KNM-CH 1 was recovered from a horizon in the upper part of the Chemoigut Fm, and is thus dated to > 1.42 Ma, which agrees well with faunal correlations and paleomagnetic studies; the cranial fragments

PREVIOUS DESCRIPTIONS AND ANALYSES The hominid face KNM-CH 1 was initially described by Carney et al. (1971), to whom it seemed "very likely that i t . . . is sampled from a population of evolved robust australopithecines, most likely descended from A. boisei" (p. 514). Partly this conclusion was based on an inference of relatively large (though unquantificd)

33

34

SITE

brain size. This feature was disputed by Szalay (1971), who produced an alternative reconstruction of the anterior cranial fossa and suggested that the specimen represented a female, rather than an "evolved," robust australopith. In turn, Walker (1972) defended the original interpretation, adding that on the grounds of size the specimen was more likely to be male. When Gowlett ct d. (1981) described the five fragments of the cranial vault KNM-CH 303/304, they noted that the specimen combined an anteriorly situated sagittal crest with a compound nuchal crest: a feature then known from only one other hominid, O H 5. O n this and other grounds they referred the cranial vault, and by extension the original face, to Australopithecus bolse'u and noted that the new specimen failed to provide support for the notion of an "evolved" form of robust australopithccine at Chesowanja.

MORPHOLOGY A single morph seems to be represented at Chesowanja. It appears most comparable in preserved characters to the O H 5 cranium from Olduvai, though the latter lacks the upper molar cingula that are present here. KNM-CH 1. Very incomplete subadult cranium with horrendously crushed, distorted upper face with part of orbital region, very crushed anterior and middle cranial fossae, and partial cranial base ( C H 1A). Also R half of maxilla with alveolus of RI1, partial alveolus for LI1, RI2 root, and R C - M 3 ; M 3 just beginning to erupt. ( C H IB). Also some other fragments of this individual, including 1C, D and E. 1C is possibly part of the frontal region above the orbit (indicating a modest posttoral plane). Other bits arc nondescript. /. KNM-CH IA. Preserves a very broad interorbital region; the sinuses pervading it extended at least to the level of the superior part of the lacrimal fossa. Glabellar region is broken off; it reveals cavities anteriorly (upward extension of maxillary sinuses?) as well as more superiorly, where (on the R), an a/p deep sinus runs laterally through the supraorbital region to past the orbital midline. The nasal bones appear to have been thin, inferiorly tapering, and slightly raised above the level of the bone lateral to them. The region of the nasal bones is essentially flat, but with a broad raised keel in the midline; in the preserved area there appears to have been no flexion of the nasal bones. The frontal processes of the maxilla appear to have

KNTUIKS

faced frontally. O n the R, the lacrimal fossa and cres are preserved. The anterior lacrimal crest u somewhat anteriorly displaced onto face; the poster! lacrimal crest lies behind and well lateral to it (thu the fossa faced obliquely anteriorly). Internally, the orbital cones are somewhat approximated, and the region between them is very deep (th cones rise well above the plane of the cribriform plate). T h e frontal crest arises very high up. The frontal lobes probably extended halfway fonvard alon* orbital cones. O n the R, the lesser wing of the sphenoid is narrow m/1 and long a/p. The hypophyseal region is very crushed. T h e optic groove was well excavated. O n the L was a well-developed anterior clinoid process. Also as seen on the L, the ledgerlike posterior margin of the lesser wing of the sphenoid projected into the region of the middle cranial fossa. Part of the dorsum scllae is preserved; this structure would have risen quite high. T h e tuberculum scllae is crushed over what had been a shallow, wide hypoph. seal fossa. 2. KNM-CH IB. In K N M - C H IB the anterior part of the nasal cavity is preserved; it appears to have flowed smoothly into a long, quite prognathic nasoalvcolar clivus. T h e internal width of the navJ fossa was not very great inferiorly. O n the R, the region of the maxillary sinus is exposed, showing th.it the sinus extended into the anterior root ot the zygomatic arch. T h e anterior root of the zygoma was apparently quite forwardly facing. It took origin very anteriorly, over P I , and moderately close to the alveolar margin. T h e nasoalvcolar clivus is long a/p, anteriorly sloping; its surface bulges over the II roots. The clival was also confluent with the laterally guttered floor ot the nasal cavity. T h e front of the palate was not very broad, but ran straight across. T h e cheek tooth rows would have diverged slightly, in a straight line behind the C. T h e palate is very long a/p and is quite deep posteriorly, with a continuous slope forward to the anterior alveolar margin. Its sides arc relatively steep at the rear. T h e palate was probably not very wide in comparison to its length. T h e incisive foramen is sin* gle and apparently large; it lies at level of PI Mllltc close to the Is, and may have extended forward as a groove. T h e greater palatine foramen is quite large and is forward-opening, without a pronounced neurovascular groove in front. T h e vomer would have extended quite far forward, to the inferior nasa margin. The pterygoid plates are thick, vertical, and

G II £ S O WAN J A

set far apart; the lateral plate is more robust than the medial one. The II alveolus is ovoid, larger than alveolus of 12. The C crown is very small and short, with a very sloping buccal side and a slightly mcsially placed apex. For its size it would have been very wide b/1, tapering rapidlv to the apex. A distinct lingual heel with a vertical pillar rising from it divides the lingual surface unevenly, into a compressed anterior fovea and a shallower, more expansive posterior fovea. P 1 - P 2 bear subequal protoconcs and paraconcs, long stout postcingulae and short stout preprotocristae that run mcsially around the paraconcs. These structures arc delineated by deep grooves. P 1 - P 2 lingual surfaces arc more bulbous and sloping than the buccal surfaces. PI is large and ovoid in occlusal outline, with low, somewhat peripherally placed paracone and protoconc, deep fissurclikc anterior and posterior foveac, and some accessor}' grooves. P2 is much larger and slightly more enlarged lingually than buccally, though it is generally ovoid in oudinc. The P2 paracone and protocone are also low and peripherally placed; a thick postcingulum comes down the side to join the base of the protocone, creating a deep, m/d long posterior fovea fissure. The anterior fovea is much shorter than the posterior. The Ms increase in size and wrinkling from M 1 - M 3 . In all, a stout preprotocrista arcs forward around the paracone and an equally stout postprotocrista runs directly up the lingual face of the metacone. The M 3 postprotocrista is bisected by a deep groove. The lingual slope of the M s increases toward the rear. The lingual molar cusps are compressed toward the side of the crown. The hypocones are increasingly limited distally by stout, increasingly subdivided postcingulae. M l is narrower b/1 than P2, and is roundedly square, bulging d/1; its cusp apices are quite worn and peripheral. The M l postcingulum is thick and creased; it comes partway down the side of the very b/1 wide hypocone. M 2 is larger than M l ; M 3 is larger again. M 2 - M 3 have very thick preprotocristae that run anteriorly around the paracone, being interrupted in the parastylar region by a crestlikc structure. As in M l , the M 2 - M 3 hypocones are very wide b/1. In AI3 a thick, beaded postcingulum runs lingually around the hypocone. The M 3 was probably impacted; its unworn surface is highly cuspulated, including grooves along its lingual surface, and appears ^ be almost entirely surrounded by a cresting system. The surface of the M 2 was probably less cuspulated; its lingual surface bears grooves (also seen in M l ) .

35

3. KNM-CH1C. This is an anterior portion of a R frontal, at the anterolateral extremity of the neurocranium. The bone is not markedly thick. Given the fragment's probable location on the cranium, the indications arc that the frontal was well pneumaticized. KNM-CH 303A-E. This consists of various cranial fragments, presumably from one individual, including a bit of the top of the skull (303B). This piece contains a low sagittal crest that bifurcates into two low, parallel crests a few centimeters behind bregma, and also includes part of a L parietal with some of the coronal suture. To judge by the side view of this fragment, the profile of the skull would have been fairly flat. 303A is a crushed, weathered occipital fragment that shows a depression above the apparent superior nuchal line. Bone of 303B is thin; that of 303A is thicker (as expected for the occipital region). The other two bits are uninformative. KNM-CH 304. This is part of a R parietal, with parts of the coronal and squamous sutures. It is thinboned, and is an appropriate counterpart for 303B, giving the appearance of a short and somewhat lowdomed cranial vault.

REFERENCES Bishop, W. W. (ed.). 1978. Geological Background to Fossil Man. Edinburgh: Scottish Academic Press. Carney, J. ct al. 1971. Late australopithecine from Baringo District, Kenya. Nature 230: 509-514. Gowlctt, J. A.J. ct al. 1981. Early archaeological sites, hominid remains and traces of fire from Chesowanja, Kenya. Nature 29 A: 125-129. Hooker, P. J. and J. A. Miller. 1979. K-Ar dating of the Pleistocene fossil hominid site at Chesowanja, North Kenya. Nature 282: 710-712. Szalay, F. S. 1971. Biological level of organization of the Chesowanja robust australopithecine. Nature 234: 229-230. Walker, A. 1972. Chesowanja australopithecine. Nature 238: 108-109. Repository National Museums of Kenya, PO Box 40658, Nairobi, Kenya.

36

t

SITE

ENTRIES

CHESOWANJA Figure 1. K N M - C H 1. Partial R maxilla and crushed facial fragment (scales = 1 cm).

DRIMOLEN

INouiJT DE

\

PAJLEttVTOLQGE Hi NB

miners in search of calcite. The infill history of the cave has been reconstructed by Keyser et al. (2000), who recognize two main elements that were apparently deposited contemporaneously. One of these, the Blocky Breccia, was deposited through a fissure as an elongated talus cone; the other, the Cave Siltstone, consists of finer sediments washed out of the talus cone more or less concurrent with its deposition. The Blocky Breccia, which consists mainly of dolomite and chert clasts in a sandy matrix, has yielded all of the hominid fossils, plus a reasonably diverse mammal fauna that, remarkably and unfortunately, lacks equids and suids. The Cave Siltstone has produced only micromammals. Most of the hominids come from an area of rubble, known as the Collapsed Fill, that resulted from an intricate history of solution and collapse within the cavity complex. Some, however, were recovered from the miners* dumps. Parts of this breccia arc decalcified, easing the task of excavation and extraction. Radiometric dating of Drimolen is not currently possible, but Keyser et al. (2000) state that the fauna is compatible with an age of deposition of 2.0-1.5 Ma, although they note that few timesensitive mammal species are present in the fauna recovered so far.

LOCATION Cave infill site in dolomites, located in Krugersdorp District, Gauteng, South Africa, about 7 km N of the classic site of Sterkfontein (Map 4). DISCOVERY The site was discovered by A. Keyser on 9 July 1992. The first hominid fossil ( D N H 7) was found there by R. Smith on 21 October 1994. Additional hominid fossils were discovered later by J. Braga and D. Gommery, who assisted with the ongoing excavations funded principally from French sources. MATERIAL Hominids reported from Drimolen to date (Keyser, 2000) include some 79 numbered specimens (sec list in Keyser et al., 2000). These are mostly fragmentary or consist of isolated teeth (many of the latter deciduous), but they include the first skull, D N H 7, consisting of a cranium and mandible with virtually complete dentition (initially prepared by R. J. Clarke and later assembled by A. Keyser), and the large mandible DNH 8, also with an almost complete dentition. DATING AND STRATIGRAPHIC CONTEXT Drimolen, like the classic Transvaal australopith sites discovered prewar, is a former cave system formed by solution in Precambrian dolomites and subsequently infilled with rubble. The fossiliferous breccias were originally exposed (and partly removed) by lime

PREVIOUS DESCRIPTIONS AND ANALYSES The cranium with mandible D N H 7 and the mandible D N H 8 were described and illustrated by Keyser (2000), and the rest of the Drimolen hominids were listed and briefly discussed in an accompanying article

37

Murium Nntlonn! il'Mictolre Naturelle L^pirterritfnt eV Fr6histoire 1, mo f l m ^ Panhard _

1

38

SfTE

by Kcvser et al (2000), who found that their "distinctive dentition and morphology . . . leave little doubt that both specimens belong to P[aranthrspus] rcbusiuT (p. 191), though he noted that they the}- expand the morphological range of the species. He further proposed that the more lightly constructed cranium and mandible represent a female, and the more heavily built mandible a male. Keyser et al. (2000) focused on the deciduous hominid teeth from Drimolen, conclud-^ ing that there is "no consistent and exclusive pattern or metrical and morphological similarity between the Drimolen deciduous dentition and either the Kromdraai or Swartkrans deciduous samples" (p. 197). These findings, they opined, "effectively weaken the hypothesis of a species level distinction in the South African australopithecines, and support the proposition of a single, variable species, P. rofaistiis." (p. 197). No endocranial volume estimate has yet been published for D X H 7, although a figure of about 530 ml seems probable (A. Keyser, pers. comm.). MORPHOLOGY Specimens thus far described from this site appear to fall into a single morph. Analysis of the larger assemblage will reveal more variety. DNH 7. Adult cranium consisting of a crushed and rejoined partial braincase lacking much of the base and missing most of the L zygomatic arch and some parts of the L parietal. The facial skeleton is missing most of the L orbit, a large part of the L zygomatic region, some of interorbital region and upper nasal bones, part of the palate, and much of the nasal cavity floor and part of the L nasoalveolar clivus. The cranial vault bone is in places relatively thick. All upper teeth are present except for part of L P l and RI1; all are very-to-extremely worn. There is also a mandible lacking its rami and part of the R corpus. All lower teeth are present, very worn; R I I and M l are broken. 1. Partial cranium. This skull is relatively small, tall, narrow and long. Overall, the skull is broad low down, with a narrow neurocranium sitting above. Seen from above, the braincase was probably ovoid, tapering gently forward toward the moderate postorbital constriction. The broad glabellar region swells out slightly in front of the preserved R supraorbital margin, which retreats gently from it. As estimated mostly from the R, the face was bizygomatically broad, with a tapering lateral orbital profile so that superiorly the

ENTRIES

face becomes narrower toward the orbits. In side vie* the a/p short face curves slightly out and down. Jud»ins from the preserved postglabeilar region the frontal profUe sloped gently up to the midsagittal region, ar*i then curved down more strongly across lambda to the vicinity of the external occipital protuberance. Fro^ this point, the nuchal plane curves down and forvva: \ quite strongly, and is not undercut at all in profLV Seen from behind, the occipital plane appears modei arelv wide but ven* short s/i and the broadest point «.f the cranium is across the laterally bulging mastoid above these, the supramastoid crests or swellings a»e prominent. Medial to each supramastoid swelling, the side wall of the braincase curves in quite strongv before becoming more vertical across the squamosal/parietal transition. As seen on the R, the cranial side wall is vertical for a short stretch before curving medially to peak ven' gently at the sagittal suture. There is no sagittal cresting. The frontal slopes gently. The supraorbital margin is moderately tall s/i, but is not distinguished as a torus; it bears a large frontal foramen just lateral to midorbit. No orbital roof is preserved; the bone at the anterior ed^e curves strongly but smoothly onto the anterior surface of the supraorbital region and then continuously back onto the frontal plane. The area across the top of the orbit and down its side is thickened, rounded and of uniform height across. The bone flattens out a bit lateral to the orbit, but only at the lower part of the very s/i tall frontal process ot the zygomatic. Judging from the preserved R side, the orbit is s/i tall, m/1 narrow, with rounded corners that give it a generally ovoid shape. The glabellar region is broad and probably tapered interiorly to a narrower interorbital region. T h e postglabellar plane is moderately long and sunken, rising laterally to a flatter, sloping postsupraorbital plane (which would have been a posttoral plane had there been tori). Nasion is not preserved, thus it must have been situated low down. T h e R temporal line is well defined; it rises high up on the zygomatic process of the frontal and runs fairly straight medially and posteriorly throughout its posterior extent. It appears from the preserved upper parts of the frontal that the temporal lines continued to converge toward the midline, but without producing a sagittal crest. T h e temporal lines do not delineate a frontal trigon, since they are not raised above the level of the bone medial to them. The preserved R maxillary frontal process is Atf and forwardly facing; it appears to preserve some ot

D u i MOM; N

the nasomaxillary suture (as docs the L side), indicating that the inferior part of the nasal bones broadened a little. Probably the entire intcrorbital region across the nasal bones was relatively flat (but there may have been some elevation across the nasals inferiorly). On both sides a relatively large, downwardly facing infraorbital foramen lies far below the orbital margin; the bone right above the foramen is moderately concave. The surface between this depression and the nasal aperture is slightly raised into a low "pillar" that appears to continue down along nasal aperture margin as far as roots of C - P l . A shallow fossa (not a distinct groove) widens inferiorly, below and behind this low facial pillar. The lateral crest (margin) of the nasal aperture is roundedly blunt. Just inside the aperture, a very thin vertical crest curves posteriorly low down. Behind this crest is another thin but tall vertical crest, followed by a third crest further back, and finally by what might be a broad lacrimal canal. There is no identifiable conchal crest. T h e inferior margin of the nasal aperture is not well defined. In frontal view, the lateral nasal crest curves strongly inward to a midline peak of bone in the position of the anterior nasal spine; this produces a double gutter in front of the nasal cavity floor. The nasoalvcolar clivus is short and apparently gently curved; it flows smoothly back into the nasal cavity to form the gutters. Externally, between the facial pillars, the nasoalvcolar clivus seems to be somewhat concave. The anterior root of the zygomatic arch takes origin above region of P 2 - M 1 , and close to plane of the infraorbital foramen. Viewed from the front, the anterior root of the zygomatic arch curves out strongly laterally, from low down. From the side, the infraorbital plane faces forward. The inferior margin of the anterior root of the zygomatic arch lies slightly more anteriorly than does the inferior margin of the orbit. As preserved on the R, two large zygomaticofacial foramina lie far below the inferior orbital margin. As also seen on the R, the zygoma curves broadly laterally and back around the temporal fossa. The squamosal appears to have been quite long a/p, and was probably low s/i. T h e anterior squamosal did not form a corner into the temporal fossa. The preserved alisphcnotcmporal (anterior squamosal) suture is vertical. The preserved inferior part of the alisphenoid shows a distinct corner with a crest along it (i.e., an infratemporal fossa was present). The posterior root of the zygomatic arch takes origin just in front of the large, round auditor)' meatus, and expands laterally forward (producing a shelf over the articular

39

fossa) as well as superiorly (forming a lateral wall to the shelf). The posterior root of the zygomatic arch extends posteriorly as a thick, low, supramcatal crest that flows back and slightly up over the puffy supramastoid region to terminate at the edge of the squamosal, in front of the parietal notch. As seen on the R, the supramastoid crest is separated from the mastoid region by a shallow sulcus below it. The parietal notch forms more or less a right angle, and the junction of the temporal and parietal bones is fairly horizontal (i.e., the temporal does not obliquely overlie the parietal). The articular fossae arc fairly wide m/1, very long a/p, and quite deep; they extend under the shelf formed by the posterior root of the zygomatic arch. T h e anterior walls of these fossae slope very steeply forward. There is no articular eminence. Medially, the fossae flow smoothly onto the sphenoid, and laterally onto the base of posterior zygomatic root. The posterior walls of the fossae slope more gently onto the anterior face of the ectotympanic tube medially, and laterally onto a well-developed postglenoid plate. Both fossae are closed off medially by a short, stubby medial articular tubercle. T h e ectotympanic tubes are wide; they extended quite far laterally, but not fully. T h e L tube bears low posterior and anterior ridges along its surface. T h e posterior ridge is longer, it lies lateral to the carotid foramen, runs from anterior to this foramen almost to the meatal edge, and is probably homologous to the vaginal process. The carotid foramen is small and medially facing. The anterior ridge is shorter and lies medially, along the midline of the tube. On the L, the slender styloid process is glued into a depression in the posterior surface of the "vaginal process"; on the R, there appears to be a vacant styloid pit close behind the carotid foramen. As better seen on the R, a small stylomastoid foramen lies at the juncture of the posterior margin of the ectotympanic tube and the region of the mastoid notch; it is well lateral, and slightly posterior to, the styloid pit. As preserved on the L, a distinct pseudostyloid process lies quite medially on the petrosal, in line with a small and rounded foramen ovale lying directly behind the lateral pterygoid plate base. On both sides, another foramen lies directly behind the foramen ovale, in the petrosphenoid fissure; it does not penetrate through the cranial base, but seems to join the carotid canal. The foramen spinosum is small; it lies entirely in the sphenoid (not temporal), and close to the petrosphenoid fissure.

40

SITE

The mastoid regions bulge laterally, and have curved (rather than flat) and m/1 broad posterior surfaces. The tips of the mastoid processes are ridgelikc, and barely projecting. On both sides, the mastoid notches arc moderately deep and broaden anteriorly. Posteriorly, the notches extend onto the posterior surfaces of the mastoids, where they arc delineated by a perceptible posterior margin. Medial to the mastoid notches, the bone swells downward from the paramastoid region to just medial to the occipitomastoid suture (paramastoid or occipitomastoid crests are not identifiable). Long, thin, distinct Waldeyers crests lie well medial to the occipitomastoid sutures. Between each crest and the occipitomastoid suture is a long, slightly depressed musclc-attachmcnt surface. The parietomastoid suture is moderately long a/p. The lambdoid suture appears to run quite sharply upward from asterion toward the missing region of lambda. As better seen on the L, the nuchal line is most distinct medially, where it demarcates bilateral ovoid depressions that lie high up and are separated superiorly by a very long, flat, narrowly V-shaped external occipital protuberance. The occipital plane tilts gently forward, while the much longer nuchal plane curves gendy but steeply down and forward without undercutting it, especially in the midline. Close to the area of the missing foramen magnum there is a trace of an external occipital crest. The palate is U-shaped, with a shallow curve across the front; the cheek tooth rows are slightly divergent. The palate is very shallow behind the incisors, and deepens steadily toward M 3 , where its walls are vertical. As reconstructed, there is no evidence of an incisive foramen. The face seems to curve up a bit anteriorly. Internally, not much is discernible. Parts of the infraorbital canal are visible on both sides (suggesting that the infraorbital neurovascular bundle began its descent far back in the orbital floor). The maxillary sinus extended posteriorly over the region of M 3 ; anteriorly, it was contained behind the facial pillar (lateral to the nasal aperture). The maxillary sinus penetrates laterally into the zygoma (but to an undeterminable extent), and superiorly it extends far up into the maxillary frontal process. Broken bone reveals the complete absence of a frontal sinus. T h e frontal crest was stout, and probably long. The frontal lobes were very narrow m/1, but continued all the way to the front of the orbits. T h e impressions for the occipital lobes point more back than down and are smaller and shallower than

ENTRIES

those for the cerebellar lobes, which were separat A • the midline by an apparently wide internal occin*11! crest. The L transverse sinus is discernible; the R o • not. Both sigmoid sinuses are well developed and I** entirely within the petromastoid region; the L sim * single, as probably was the R. The superior surfaces of the petrosals are broad and essentially flat; there is trace of a superior petrous sinus on the R. The subarcuatc fossae are closed over. The middle branch of th middle meningeal artery runs along the "corner" between the petrosal and the squamosal. There are verv few other impressions of meningeal vessels. All upper teeth are very worn, but originally they would probably have been very high crowned. In their present state, the Is and Cs are small relative to the cheek teeth, especially the Ps.The l i s apparently were much larger and more spatulate than the I2s. The II roots are much bulkier but apparently are not much longer than the slender 12 roots. As seen on the R, the C root is long and not bulky; it extends to the base of the nasal aperture. The base of the C crown is not bulky, and the crown itself would have been slender. T h e Ps, especially as seen on the R, are huge; both are quite narrow b/1 and wide m/d, with well-curved buccal and lingual surfaces. The P i was longer m/d buccally than lingually; the P2 the reverse. The Pi is slightly narrower b/1 and shorter m/d than the P2. As seen on the L, P I had, and P2 has, three distinct roots. The P2s are wider b/1 than the M i s . The molars decrease slightly in size from M l to M3. The protocone is large and somewhat mesially and internally placed, while the metacone decreases in size from Ml to M 3 (so the teeth become more oblique buccally). The size and position of the protocone truncates the buccal cusps. The hypocone is large in all three molars; at least as seen in M 2 - M 3 , it swells the tooth buccally. As seen on the RM2, the groove that delineates the hypocone from the protocone courses almost directly buccally before turning quickly and for a very short distance to stop at what appears to be a very short postcingulum that terminates on the distal side of the metacone. This was probably also the case with the M l hypocone. On the M 3 , however, the groove courses right to the distal side of the metacone and is crossed by a short, d/1-directcd groove that runs from the base of the paracone, along the base of the metacone and to the short but basally thick and buccally tapering postcingulum. There was probably some enamel cuspulation or wrinkling on the Ms. As seen on M 3 , there is some lingual slope.

DltlMOLKN

2. Mandible. The corpora lack rami and are badly damaged underneath. They probably were not very s/i tall, but were very wide m/1. There is a shallow curve externally around the symphysis. In profile, the symphysis probably curved down to the inferior border. The postincisal plane is very long, moderately sloping, and quite concave. Its area is largely missing, but there may originally have been a superior transverse torus. Bilaterally, small depressions lie below I2-C; the bone between them appears raised, but actually continues the general curvature. On the R is a large mental foramen, and on the L a large plus a tiny one. The mental foramina lie very low on the outwardly bowed corpora below l\2.The anterior root of the ramus originated at the distal end of M l ; the gutter is very large at the level of M3, which is hidden from the side by the ramus. The gonial regions are broadly curved and slightly inwardly reflected, with some muscle scarring around the angle externally. Internally, on the better preserved L side there is no indication of a mylohyoid line or a submandibular depression. The internal alveolar crest is not well developed. On the R is a long mylohyoid groove. On both sides a series of muscle scars lies internally around the gonial angle. All teeth are present, but are very-to-extremely worn, with the Rll and R M l partly broken. The teeth look a bit small compared to the width of the mandible. The anterior teeth appear small relative to the Ps, which appear large relative to the Ms. The Us arc narrow m/d compared to the 12s. As seen on the L, the Is are long rooted, and possibly they were originally high-crowned. The C crowns angle back slightly trom their necks, and were apparently narrow m/d. As seen on the R, the C crown bore low mesial anil distal margocristids. On the L, the PI is about as wide b/l, and on the R is wider than, the P2. On both sides, the Pi is shorter m/d than the P2,The Pis are essentially narrow b/l and ovoid; they probably had a centrally placed protoconid and a mesially placed metaconid with a cristid coursing d/1 from it that swelled the d/1 corner of the crown before turning up the side of the tooth to terminate on the side of the protoconid. The "2 is shorter m/d, and more rounded buccally than lingually; the lingual side is also oblique, with a swollen-out d/1 aspect. As seen on the U the P2 protoconid was mesially, and metaconid very mesially, placed; a thick cristid comes from the side of the metaconid to the d/1 corner of crown. The M2 is wider b/l than the M l . All Ms are of about the same M width, and increased very little in length from M l

41

to M 3 . On all Ms the hypoconulid extended buccal to the midline. Judging from the RMs, the base of the M l hypoconulid is wedge-shaped and contacted the metaconid while "cutting in front of" the entoconid; on M2 the base is blunter and contacts the other cusps equally; and on M3, it is very blunt with a small metaconid and m/d long entoconid contact. The entoconid is m/d long at least on M 2 - M 3 . As seen on M 3 , the intercusp grooves form an m/d-oricnted and slightly sinuous groove along much of the length of the crown, lingual to its center. As also seen on the LM3, a d/1-facing cuspulid lay between the entoconid and the hypoconulid, which is quite buccal and oriented obliquely m/1 to contact the entoconid. The M3s are rounded distally and are narrower b/l distally than mesially; the buccal cusps were probably more internally placed than the lingual cusps, and the long talonid basin was quite constricted. ONH tS\ R and L corpora lacking rami and broken down the midline. They contain LC-M2, M3 glued on; R12-M1, broken M2, plus M 3 glued on; and alveoli for LI2 and R l l . The corpora are fairly tall s/i and relatively wide m/1. The jaw was relatively narrow at the front, and flat across or gently curved. In profile there is a gentle symphyseal curve, down and back. The postincisal plane is long, gently sloping, and turns down level with P2 to form a superior symphyseal torus. As seen on the R, below the torus, there was a fairly welldeveloped depression; inferior to this is a distinct inferior symphyseal torus. Bilaterally, shallow depressions lie externally below the 12 and C roots; otherwise, there is no morphology in this region. A large mental foramen is situated halfway down the corpus on the R, and between P 1 - P 2 on the L, where a tiny foramen lies posterior to it. On the L there is a short, shallow, posteriorly facing digastric fossa. The anterior root of the ramus rises below A12; its margin may not have ascended steeply. There is some evidence ot a mandibular gutter, but no indication of a mylohyoid line or of a submandibular depression. The lower teeth are moderately worn. The preserved 12 was slender and probably very tall-crowned. The Rll alveolus is only slightly larger than the 12 root. The Cs are also relatively narrow, with somewhat concave buccal sides; they probably had a very steeply sloping distal margin and a much tn/d shorter mesial margin. Lingually there is a moderate heel; the distal fovea is larger than the mesial fovea. The PI is almost

42

S IT K E NTUI K S

as wide b/1 and about as long m/d as the P2. On both Ps the protoconids are fairly mcsially placed, and the mctaconids are very mesial indeed. The Ps have buccal pillars on the distal aspect of the protoconids. The lingual sides of the Pis arc obliquely oriented, with distension of the d/1 corners; the mesial sides are b/1 narrower than distal sides. A small anterior fovea was probably closed off by a thick cristid. In both PI and P2, a thick cristid runs from the buccal pillar to the d/1 corner, then up to the nietaconid; as seen on the P2s, there is a thin groove between the cristid and the distal side of the protoconid. The Ps arc cuspidated or at least crenulatcd. The lingual side of the P2 is longer m/d and straighter than the more rounded buccal side. P2 and M l arc of about the same width b/1. T h e Ms probably increased in m/d length from M l to M 3 (assuming the very large and inconsistently unworn M3s really arc from this specimen). On all Ms the entoconid is small, and on M 3 it is the most internally truncated. Also on all A Is, the mctaconid is longer m/d than the protoconid, and the wedge-shaped hypoconulid, more buccal than lingual, is distally quite wide b/1. As seen on both M3s and faintly recognizable on the R M l and the LM2, the paracristid is long m/d along the protoconid, but thins considerably around the nietaconid. The M3s arc narrower b/1 distally than mesially, with a blunt hypoconid base diat extends slightly over the midline and makes a

somewhat broad contact with the nietaconid ami a longer one with the entoconid. On M 1 - M 2 th hypoconid is more wedge-shaped and makes a small nietaconid and a somewhat longer entoconid contact M 1 - M 2 were probably rounded distally, but not as tapering as M 3 . T h e M3s have sonic beading between the hypoconid and entoconid, a distinct cingulid around protoconid base (possibly also on M1-M2) and evidence of cuspulation. The M3 talonid basin is long m/d and quite constricted b/1. A small stylid-likc structure lies low down between the hypoconulid and hypoconid.

REFERENCES Kcyscr, A. W. 2000. The Drimolcn skull: the most complete australopithccinc cranium and mandible to date. S. Afr.J.Sci 96:189-193. Kcyscr, A. W. ct al. 2000. Drimolcn: a new hominidbcaring site in Gautcng, South Africa. S. Afr, J. Sci. 96: 193-197.

Repository Department of Anatomy and I luman Biology, University of the Witwatcrsrand Medical School, York Road, Parktown, Johannesburg 2193, South Africa.

DRIMOLEN

DRIMOUEN

unsealed).

43

Figure 1. D N H 7. Partial cranium, mandible and dentition (scales = 1 cm; close-up of anticular region is

i

44

DRIMOLEN

Figure 1. (Continued).

DRIMOLEN

Figure 1.

(Continued).

SITE

46

DRIMOLEN

DRIMOLEEN

ENTRIES

Figure 1.

(Continued).

Figure 2. D N H 8. Partial mandible and R petromastoid region (scales = 1 an)-

DRIMOLEN

DRIMOLEN

47

Figure 2. (Continued),

J

FEJEJ

northwest. Kappclman ct al. (1996) rcdatcd two lavas overlying FJ4 at just under and just over 4 Ma by single-crystal Ar/Ar. This agrees with reversed polarity measured in both deposits that fixes the age of the fossils at between 4.0 and 4.18 Ma. A date of marginally more than 4 Ma for the hominid teeth thus appears firm.

LOCATION Fossilifcrous exposures in the vicinity of the Fcjcj Police Post in southern Ethiopia, some 25 km ENE of the northeastern corner of Lake Turkana and 20 km N of the border with Kenya (Map 1). DISCOVERY First hominids found September/October 1990 by a team representing the State University of New York at Stony Brook and the National Museum of Ethiopia (Fleaglc et al., 1991).

PREVIOUS DESCRIPTIONS AND ANALYSES In their initial announcement of the hominid teeth from Fejej, Fleagle ct al. (1991) remarked on their close similarity to those of Australopithecus afonnsis, and referred them to that species. Kappclman ct al. (1996) were even more adamant in that conclusion, but in 2000 Van Couvering, presumably on grounds of time, suggested that they might better be allocated to Australopithecus anamensis (not yet named when the Kappclman ct al. contribution was written).

MATERIAL Seven isolated teeth (NME FJ-4-SB-la through If). DATING AND STRATIGRAPHIC CONTEXT The primary stratigraphic marker for the late Tertiary in the Fejej region is the Harr Basalt. The basalts of the Harr Formation underlie up to 60 meters of early Pliocene sediments laid down by the ancestral Lake Turkana (Asfaw et al., 1991; Fleagle ct al., 1991). Davidson (1983) obtained a conventional K/Ar date of 4.2 Ma for a basalt outcrop in the northeastern sector of the region, while Asfaw ct al. (1991) reported a date of 4.42 Ma from another Harr exposure overlying two Pliocene fossil localities, and Fleaglc ct al. (1991) obtained a slightly younger Ar/Ar date of 3.6-3.7 Ma for the basalt overlying the hominid locality FJ4, a few km to its

MORPI lOLOGY NME FJ7A 5S-1. Eight tooth frJff1,c"^ "J heavily worn and broken. Amongst these t c c l \ a small RI>» and V2 with buccal roots that di« ^ slightly from one another well above the^ n c ^ ^ both, the mesial root is distended m/b. A 1*1 Jj^j mesially shifted paracolic, with a slight sWC,,l"f* Vp! to it, and was m/d longer buccally than l " 1 ^ " 1 ^ a is ovoid. There is a fragment of a lower

48

F EJ EJ

fragment of a lower M root (unnumbered), another apparent lower M fragment, and a lower LM that is associated with a broken root (that does not fit, however), and an unnumbered enamel chip. T h e latter lower LM (an Mi or M 2 ) would have been quite small. The LC 1 has a very long, strongly m/d compressed, slightly recurved root with a strong vertical groove along the midline of its mesial surface. The C crown is broken; it was compressed m/d and would not have been very bulk}-. FJ7A 5S-2. An unworn RPj, small and single rooted (its tip is pathologically bent); the root is compressed m/d. There is a vertical buccal groove between the protoconid and postcingulid, with a conulid-like structure in the posterior basin.

REFERENCES Asfaw, B. et al. 1991. Fcjcj: a new palcoanthropological research area in Ethiopia./. Hum. Evol. 21:137-143. Flcaglc, J. et al. 1991. New hominid fossils from Fejej, southern Ethiopia./. Hum. Evol. 21:145-152. Kappclman, J. et al. 1996. Age of Australopithecus afarensis from Fejej, Ethiopia./ Hum. Evol. 30:139-146. Van Couvering, J. A. 2000. Fcjcj. In: E. Dclson ct al. (eds.), Encyclopedia of Human Evolution and Prehistory. New York: Garland Press, pp. 267-268. Repository National Museum of Ethiopia, PO Box 76, Addis Ababa, Ethiopia.

Figure 1. Left and Center: N M E FJ7A 58-2, lower RP1; Right: N M E FJ7A 58-1, upper LC (scale = 1 cm). FEJEJ

49

HADAR

Johanson, Taieb and Coppcns (1982); famous examples among them include the "Lucy" partial skeleton (AL 288-1), and the "First Family" from Locality 333, over 200 fragments representing at least 13 individuals. There is no account of post-1990 discoveries comparable to the special issue ofthe American Journalof 'Physical Anthropology (vol. 57, no. 4, April 1982: "Pliocene Hominid Fossils from Hadar, Ethiopia") that brought together research on the 1973-77 collections; but notable more recent contributions include Kimbcl, Johanson and Rak (1994) on the impressively complete cranium AL 444-2 and various other specimens, and this volume goes to press simultaneously with the appearance of a monograph (Kimbcl, Rak and Johanson, 2004) on this cranium that also includes a listing of Hadar hominid specimens recovered during the 1990-94 and 1999-2001 field seasons.

LOCATION Extensive fossil collecting area in the Afar Depression of northeast Ethiopia along the Awash River, some 300 km N E of Addis Ababa (Map 1). Nearly 400 individual collecting localities have been identified in the region. DISCOVERY The fossil potential of this area was recognized by the geologist M. Taieb during the late 1960s, leading to a paleontological survey by Taieb, D. Johanson, Y. Coppens and J. Kalb in 1972, and the formation of the International Afar Research Expedition in early 1973. On October 30, 1973 Johanson found the first hominid fossils (AL 128-1 and 129-la/c) at Localities 128/9. Subsequent field seasons up to 1977 produced a veritable trove of hominid and other vertebrate fossils, but because of political difficulties field research was suspended in 1977. Collecting resumed in 1990 by the Hadar Research Project, initially under the direction of Johanson, W. Kimbcl and R. Walter, and since then has resulted in numerous new hominid

DATING AND STRATIGRAPHIC CONTEXT Hadar lies in a Plio-Pleistoccne sedimentary basin some 150 km long by 60 km wide that lies in the Atar Depression at the northern extremity ot the La*t African Rift. Taieb ct al. (1976) define the Hadar site as "the area of Plio-Pleistoccne sediments exposed in the drainage of the Awash basin in the tributaries o Gona, Sidi Hakoma, Kada Hadar, Ounda Hadar and south of the Awash River." (p. 289). They recognized all these exposures, which crop out over an area about 100 sq. Ian, as belonging to the Hadar Formation, with a known thickness of sediments varying

finds. MATERIAL Several hundred hominid fossils in various stages of fragmentation, and almost all of them currently attributed to Australopithecus afarensis by their discoverers, have been recovered from the many localities at Hadar. Finds up to January 1977 were listed by

50

HAD A K

from ISO to 300 meters, though the top and bottom of the sequence have not yet been defined. The fluvial and lacustrine sediment pile is interrupted by volcanic marker beds, and both sedimentology and paleontology indicate that it was laid down in considerably wetter and more vegetated conditions than those prevailing today. Episodically, however, drier conditions with patches of grassland are indicated. Dating of the lower marker beds was initially controversial (see Walter and Aronson, 1982), but has latterly been largely settled by technological advances, notably single-crystal Ar/Ar dating (see Walter and Aronson, 1993; Walter, 1994). From the bottom up, the sequence is as follows: T h e Basal member is limited above by the Sidi Hakoma Tuff at 3.4 Ma; the Sidi Hakoma member above this is capped by the Triple Tuff dated to 3.22 Ma; the Denen Dora member above this is capped by the Kada Hadar Tuff at 3.18 Ma, and the uppermost Kada Hadar member continues up beyond the Bouroukie-3 Tuff dated to 2.33 Ma. Intermediate dates on interspersed volcanics agree with this sequence; thus the Kadada Moumou Basalt toward the top of the Sidi Hakoma member dates to 3.2$ Ma, and the Bouroukie-2 Tuff" fairly high in the Kada Hadar member dates to 2.92 M a . Vertebrate (including hominid) fossils occur throughout this sequence, notably in the three upper members, between about 3.4 and 3.0 Ma. T h e ages of many of the best-known A. afarensis fossils from Hadar have been quite precisely pinpointed, including the A.L. 444-2 cranium at 3.0 Ma; the A.L. 333 "First Family" at 3.2 Ma, and "Lucy" (A.L. 288-1) at •>.18 Ma. Right at the top of the surveyed sequence, at about 2.33 Ma, comes the A.L. 666 palate that has been attributed to Homo. ARCHAEOLOGICAL CONTEXT Stone tools of Oldowan aspect have been found at Hadar, but only in the uppermost parts of the Kada Hadar member. None is known from any level yielding fossils identified by their finders as A. afarensis, although Kimbel, Johanson and Rak (1997) reported the discover}- of Oldowan artifacts in "close proximity" to the A.L. 666-1 palate. PREVIOUS DESCRIPTIONS AND ANALYSES 1 he first announcements of the hominid craniodental fossils from Hadar localities (e.g., Johanson and ^oppens, 1976) were almost entirely descriptive,

51

although it was emphasized from the start that the associated postcranial elements were those of an upright biped (sec Taieb et al., 1974, 1975; Johanson et al., 1976). Initially, the Hadar researchers divided the overall fossil collection into two groups: one attributable to a species of Australopithecus, the other to a species of Homo (see Johanson et al., 1980; Johanson and Edey, 1981). Subsequently, though, apparendy more greatly impressed by size than by shape disparities in their sample, Johanson, White and Coppens (1978) allocated all the Hadar hominids then known to the single species Australopithecus afarensis. This new hominid species, named in a notably terse and nondiscursive contribution, was based on type material from the Tanzanian site of Laetoli, even though Hadar materials composed the vast bulk of the hypodigm.The inclusion in the same species of all of the Hadar materials was objected to by various scholars, including Olson (1981), who saw Paranthropus affinities in some of the cranial fossils and Homo affinities in others, and Falk and Conroy (1983), who perceived a dichotomy in intracranial venous drainage. Another tack was taken by those such as Tobias (1980), who saw no convincing distinction from A. africanus in any of the Hadar material. But the unit}' and distinctiveness of A. afarensis were stoutly and consistently defended in such contributions as Johanson and White (1979) and White, Johanson and Kimbel (1981). Indeed the proposal made by Johanson and White (1979), thatytf. afarensis represents the stem species for all later hominids, eventually achieved the status of received wisdom (though the recent announcement by M . G. Leakey et al. [2001] of the penecontemporaneous Kenyanthropusplatyops has given pause to some). T h e various debates over the status of A. afarensis continued for years in the absence of a known A. afarensis skull from a single individual, though a composite was cobbled together by Kimbel, White and Johanson (1984; Kimbel and White, 19SS) from unassociated pieces. Finally, in 1994, a reconstructed but definitely associated cranium, from the A.L. 444 site quite high in the Hadar section, was described by Kimbel, Johanson and RaL This specimen (monographed by Kimbel, Rak and Johanson [2004] just as this volume goes to press) confirmed the essential features of the earlier reconstruction and banished most lingering doubts that not all of the elements used in that reconstruction might have belonged to members of the same species. Thus Kimbel, Johanson and Rak (1994) defended once again the taxonomic unit}' or ^'\*r-

52

SITK

the Hadar hominid samples, and their referral to the one species A. afarcnsU as defined from Lactoli. They emphasized their belief that A. afarcmis accordingly constitutes the most convincing body of evidence available for an episode of stasis (0.9 Ma) in human phylogcny. It seems unlikely, however, that doubts about the homogeneity ot the larger Hadar hominid assemblage will ever ^o away entirely, especially given the observations made later in this volume, where the morphological association of any Hadar materials with the LH4 type mandible of A. afaremis is also questioned. Similarly, the debate among those (e.g., Lovcjoy, 1988) who believe that the early bipeds of Hadar were efficient and committed terrestrial bipeds, and the growing majority (e.g., Susman and Stern, 1991) who favor the view that "Lucy" and her kin regularly used the arboreal capacities clearly retained in their postcranial structures, also promises to prove durable. Hollowav (2000) reports endocranial volume estimates of 485-500 ml for AL 333-45; 375-400 ml for AL 162-28; and 310-320 ml for AL 333-105. Hollowav and Yuan (in Kimbel, Rak and Johanson, 2004) estimate an endocranial volume of 540—550 ml for the AL 444-2 cranium.

MORPHOLOGY We have found it very difficult to sort the rather heterogeneous dental sample of hominids from Hadar localities. It might be possible, for example, to construct a lower premolar morphocline among these fossils that would support the notion that all belong to a single variable population. The structurally simple end of the morphocline would be exhibited by the specimens AL 417-la and b and AL 288-1, which have a protocone-dominated PI that posesses a descending lingual protoconid cristid with minimal development of foveae mesially and distally, and a P2 that is tightly curved on the buccal side, is shorter m/d buccally than lingually and shows minimal development of a postcingulid and mesial and distal foveae. In the middle would lie AL 266-1 and its allies, with a PI that is more m/d elongate lingually, and that has a thicker and more horizontal protoconid cristid and more distinct mesial and distal foveae, hence more noticeable development of the distal part of the tooth. The P2 is more squarcd-up due to better development of the postcingulid and the swelling of a small hypoconulid, with larger mesial and distal foveae. The most derived

E S T HIES

part of the morphocline would be represented k, 333w-60 and similar specimens, in which th squarcd-up PI bears a greatly thickened protocTin cristid that swells at its lingual terminus and may pear as a distinct rnctaconid. The mesial and A^ basins may also be more developed in these forms O P2 the postcingulid is more developed, with disr' n T distension of the d/1 portion of the tooth. However, reconciling such a lower premolar m phoclinc with the lower molar morphologies of nV same specimens is no simple matter. Specifically wh'L it would be possible to claim some similarity'in the lower M i s of AL 417-1 and 266-1 to the extent th both show some b/1 compression of a somewhat elongate rnctaconid, these teeth differ in other details such as the disposition of the hypoconulid relative to the hypoconid, the general puffiness of the cusps, the relative proportions of length and width, and the size of this tooth relative to the M2 behind. The lower M2s and M3s themselves also differ; most notably, in AL 266-1 these teeth are wider b/1 mesially than distally, and the trigonid basin is thinner and lies farther back between the metaconid and protoconid. Similarly, the A L 333-60 lower dental morph has much more elongate and relatively narrower molars than either of the preceding forms, with distinct notches not only between the protoconid and hypoconid, but between the hypoconid and hypoconulid as well. Significantly, none of the teeth from Hadar appears to be a match for any of the specimens represented at Laetoli, notably those in the LH4 mandible the holotypc of Australopithecus afarensis (see Laetoli entry)- The major point of potential similarity between L H 4 and some Hadar lower dental specimens is the lack of a metaconid on the PI. However, in L H 4 this tooth is relatively longer m/d and narrower b/1, with a thick, very- high-set (almost horizontal) and very b/1 short cristid coming off the protoconid, and with a marked crease or groove distal to it that ex tends down the lingual side of the crown. In addition, this tooth appears large relative to the P2, which in turn is truncated b/1, and thus appears narrow when compared to the M l . In general, the M 1 - M J ° LH4 arc more squared-up distally; and the ^ " " * (which are less worn than the M l ) bear, on either si e of the midline of the crown, a highly unusual pair o b/1-orientcd grooves that are situated somewhat i from the distal margin. Interestingly, none ot Hadar lower teeth has a close counterpart in the &° graphically much closer Maka sample.

IIAIIAK

The AL 417-1 lower dental morph is definitively associated with the AL 417-1 upper dental morph by virtue of occurring in the same individual. The AL 417-1 upper dental morph appears to us to include, besides (lie specimens listed below, the AL 666-1 palate usually attributed to Homo sp. O n the other hand, the upper dentition of AL 417-1 does seem to be distinct from the upper dental morph represented bv AL 444-2, which (although its upper teeth are very worn — albeit curiously less so than in the mandible attributed to the same individual) evidently had upper premolars that were larger, especially b/1, relative to the ML In addition this specimen displays a b/1 wider but m/d shorter M l and M 2 , with a less developed postcingulum, and an M 3 that is much more elongate lingually than buccally. A third upper dental morph, represented by the isolated upper M 2 A L 333x-l and the upper M l of A L 333-86, is distinguished bv the severe compression ot its cusps and their incorporation into a cresting system that surrounds a very m/d long basin that lacks any distinction between trigon and talon regions. Whereas it is typical for early hominid upper molars to have a mesially running preprotocrista, in these two teeth this crest is distinctly and uniquely exaggerated. Also uniquely, they share a well-developed prehypocone crista that terminates on the side ot the protoconc just above the level of the short postprotocrista. We are thus hesitant for a variety of reasons to describe all of the Hadar hominids as members of a single but variable morph, and have chosen to list them below in discrete groupings, whose dental morphologies are consistent among all members. This has untortunatelv involved dividing the "First Familv" fossils from localitv 333 among at least three different morph groupings, which may cause some concern, because it is widely believed that all of the members of this assemblage belonged to a single social group. This may indicate that the the taphonomy of this locality requires reexamination, or alternatively that we need a good deal more information about hominid morphological diversity in the time period represented by Hadar. Still, the morphological differences we report do not appear to be artifacts. AL 417-1 Upper and Lower Dental Morph (includes upper dental specimens A L 199-1,200- la, 417-lc/d, 486-1, and lower dental specimens AL 19S-1,200lb, 200-18,333-30,400-la, 417-la/b, 353w-48) The upper and lower teeth assigned to this morph are

53

united by the apparent association of the maxilla and mandible of AL 417-1. The upper teeth of this morph arc characterized by a hypoconc that extends distally beyond the metacone on all Ms, and that becomes increasingly separated from the protoconc in the sequence M 1 - M 3 , the protoconc being subequal or smaller than metacone on M l . These cusps arc also level buccally, a thick postcingulum lies significantly higher than the metacone and hypoconc, and there is a subsquarc M l . The lower teeth of this morph are characterized by having a morphologically rather simple, occlusally rather triangular, P I with modest mesial and distal basins; a buccally very m/d short and lingually much m/d longer P2 with no mctaconid and some d/1 swelling; an M l that is typically smaller in all dimensions than the M2 (except in 417-lb); and molar protoconids that arc subequal in size with the relatively noncomprcsscd metaconids. Ataxillae. Upper Teeth, and Crania! Remains AL 199-L R hcmimaxilla with a little bit of nasal floor. C - M 3 present (M3 broken distally), root of 12, alveolus of I I . Long, narrow palate with bowed cheek tooth row. Basically looks very much like A L 200, though it has a much more horizontally oriented nasoalveolar clivus, is shorter front to back, and has a straightcr and more vertical posterior pole. The midline keel of the posterior pole is barely visible in the floor of the nasal cavity; thus there are virtually no spines. The posterior pole of the clivus minimally overlaps a thin palate of uniform thickness. Between the clivus and the palate there is a thick midline septum that closes off* a moderately sized canal running from the incisive fossa to the foramen. T h e canal continues as a groove along the palate to the central incisor alveolus. Laterally the floor of the cavity slopes smoothly and moderately strongly down and back. There is a steep drop from the posterior pole of the clivus to the floor. The nasal aperture was apparently narrow interiorly, and the floor of the cavity flows out smoothly on to the clivus. The curve across the front of the clivus was probablv quite smooth and tight, and tooth root impressions are minimal. A shallow but long and laterall v racing fossa lies behind the slight bulge of the PI root. In profile it appears that the bone lateral to the aperture sloped back quite strongly. It also appears that the anterior root of the zygomatic arch originated modcratelv above M l . It was swollen out laterally by the maxiliarv sinus, which extends anteriorly to the

54

SITE

region above P 1 - P 2 . Trie floor of the sinus is subdivided by two lowf thick transverse crests. The palate is a bit deeper than in AL 200-1 a, but similarly maintain*. it« depth from front to back until the level of the M1/M2, behind which it becomes deeper. The greater palatine foramen lies within a substantial fossa. fnc pterygoid plates arc broken off, but apparently, as in 200-la, they lay right behind the M 3 . Most teeth arc quite worn. The root of II had been curved strongly downward, and was much larger than that of 12. There is no diastema between J2 and C, which is similar in morphology to 200-la. Other teeth are also similar in comparable detail to 200-1 a, with the notable exception of the M l paraconc being trnalJcr than the metaconc. The roots of the M l divide just above the crown. AL 200-1 a. Palate, broken more or Jess along the midline. Preserves the bottom of the nasal fossa anteriorly, as well as all teeth, most of which arc not very worn. Long and narrow palate, with slightly bowed cheek tooth rows. The inferior part of the nasal aperture is preserved, and is quite narrow. As indicated on the L, there is no distinct anterior nasal spine, but a low, raised midline keel is set back behind the nasal margin. This keel continues as an extension (i.e., the posterior pole of the clivus) over the incisive fossae. On both sides, and restricted to the rounded infcrolateral corners of the nasal aperture just inside the margin, is a very shallow fossa. The lateral portion of the floor of the nasal cavity flows smoothly downward and posteriorly. A step down occurs from the central keel to the floor of the incisive fossae. In cross section the very long nasoalvcolar clivus is almost elliptical in shape, and oriented almost horizontally. Its posterior pole extends well hack over the palate, with a long and relatively large canal separating the two. T h e L hemiinaxilla is broken so that it contains part of the R side of the midline. Looking forward into the incisive fossae there is a septum that connects the clivus with the p l a t e . To the L of the septum is a matrix-filled aperture; to the R of the septum there is a groove that runs along its length. The color of this septum matches the hone around it, and differs frotn the matrix to its left. More anteriorly, the septum appears to terminate naturally such that the canals to its L and R would have coalesced. When the R hemimaxilla is articulated with the L, the arrangement of spaces is symmetrical. Lath hcmiiiKLxilla is damaged to the side of the

ENTRIES

mlidline, which makes it difficult to be certain \ trIC palate thinned posteriorly (the palate i* tk ** ral to the midline). In profile the long clivu era relatively strongly toward the alveolar margin ^ 7 * leling the curvature of the incisor roots. Thi-' ture is continued on the I crowns. The sides frf * nasal aperture also slope back quite strongly * The floor of the nasal cavity flows smoothly the external surface of the rather flatly tram-*' i lls> i l l 1 ' Cry;jY d nasoalvcolar clivus, whose surfar* ~- ' u 11 c i 1 i « * "ace mirrors the large roots of the teeth below. As seen on the I the inferiormost portion of the maxilla adjacent tot! nasal aperture is smoothly rounded. The bone around the canine root on both sides is swollen and coalesce with a similar swelling over the P i . Behind this swelling on both sides there is a moderately pronounced but also a/p long and sideways-facin? "canine fossa," which gives a modestly "pinched" zZ pcarancc to the front of the jaw. As seen on both sides, the anterior root of the zygomatic arch originates moderately above the M l , and as suggested on the R, it faced somewhat forward. Internally, the large maxillary sinuses swell out laterally above the M l and M 2 , and are subdivided posteriorly by a three low ridges of bone. The anterior part of the maxillary sinus is confined to the region above M l . O n the R, damage reveals evidence of a small sinus in the bone lateral to the nasal margin. T h e palate itself is very shallow from behind the incisors almost to the level of M l , behind which it deepens slightly. T h e shallow lateral walls are almost vertical behind, and more or less absent in front. The greater palatine foramina are quite large, and are set in broad fossae from which deep grooves run anteriorly. T h e incisive foramen, which lies toward the distal side of P I , is relatively large and oriented forward. It 15 continued forward by a relatively broad and deep but not very long groove, in the roof of which are two shallower parallel grooves. Posteriorly there are vestiges, on both sides, of medial and lateral pterygoid plates that appear to have been coalesced inferior!). They also appear to have been parallel and not tar apart from each other. T h e Is arc extremely different in size and quite worn. The l i s are broad, spatulatc and tall crowned. Their lingual surfaces bear broad central pillars ar^ weak margocristac. Their lateral sides flare noticca / T h e smaller 12s were probably also somewhat taij crowned. Their lingual surfaces arc excavated and! po scss distinct margocristac. They may nave

ll.\n AH somewhat laterally, and they flared distinctly mesially. Thev are separated from the canines by a noticeable diastema. The RC is displaced somewhat from its alveolus, and its tip and distal margin are somewhat worn. The tip of the LC is damaged. Judging from the L side, the C crowns were originally quite tall, although these are not very massive teeth. They both have distinctly accentuated distal heels, and a steeply sloping distal margin with shorter mesial margins. Internally, there is a fairly large lingual swelling, into which flows a thin pillar that arcs down from the mesially positioned apex. Mesial to the pillar is a thin, vertical fovea bounded by a moderate margocrista. Distal to it is a broader fovea also bounded by a marjrocrista. o

The Ps, and even more so the Ms, are large relative to the Cs. The buccal side of the RP1 is missing:, and the paracone of the LP1 is chipped. Still, both Pis are moderately but distinctly larger, especially m/d, than the P2s. As indicated on the L, the centrally placed paracone would have been taller than the slightly mesially shifted protocone. These cusps are connected on their sides, mesially and distally, by thick cristae, and their bases are delineated by a transverse crease. The internal surfaces of the cusps are slightly wrinkled, and the tooth appears to be slightly longer buccally than lingually. On the P2s the buccal side is more tightly curved and shorter m/d than the lingual side. Otherwise the basic morphology of these teeth is essentially similar to the P i s . The M l is markedly worn, the M 2 slightly worn, and the M 3 is not worn at all. All are quite tall and increase slightly in b/1 width, and more noticeably in m/d length, from the subsquare M l to the most distally distended M 3 . The buccal cusps are peripherally placed on all three molars, and the lingual cusps are slightly more centrally placed on M 1 - M 2 . All three Ms bear a slight parastylar swelling at the end of a thick preprotocrista that runs around the paracone. A conulelike postprotocrista connects the bases of protocone and metaconc. A thick, short postcingulum runs from the large and slightly distally rounded hypoconc to the side of the mctacone; this crest lies higher than the cusps. The metaconc is noticeably smaller than the paracone only on M 3 . Distinct vertical fissures on the lingual side separate the hypoconc and protocone. T h e hypocone contacts, but also extends more distally than, the metaconc on all Ms. Both M3s and the RM2 arc thickly wrinkled, as also appears to be the case for the L M 2 . The M i s may also have

;o

originallv been wrinkled. The trigon basins of all molars are relatively filled in. AL 333-30. Lower Rdm2, broken and weathered. Tiny, and seems to have had a sloping buccal side, with enamel extension over the m/d root. Metaconid was higher than the protoconid, and curved distally as a long crest. The ccntroconid is moderately sized, with a deep but constricted anterior fovea between the bases of the protoconid and metaconid and a cristid running from the entoconid around the preserved lingual side of the hypoconulid, with a distinct fissure internally (cf.200-lb). AL 417-1 c. Portion of basiocciput, with part of R sphenoid reconstructed; associated with 417-la, b and d. Includes the anterior portion of the middle cranial fossa and the lateral portion of the anterior cranial fossa. Externally the specimen has part of the alisphenoid: this curves strongly but smoothly down and in, indicating no break between temporal and infratemporal fossae. Internally there is part of the orbital cone. The basiocciput broadens posteriorly quite strongly, and is very concave internally; externally it bears scars on its lateral margins, but it is essentially flat across. In cross section the bone tapers thinly posteriorly, and on the R is preserved a small anterior condylar canal. A moderate-sized sphenoid sinus is partly preserved in the midline, together with another lateral to it; both lie over the region of the superiorly confluent pterygoid plates, which may have been subparallel. The foramen rotundum lies just to the side of the wall of the hypophyseal fossa, on the floor of the middle cranial fossa, with a groove running posteriorly from it. The anterior cranial fossa extends well over the preserved orbital cone, and the alisphenoid is angled medially from back to front, suggesting some degree of postorbital constriction. As reconstructed, there appears to have been no basicranial flexion. AL 417-ld. R and L partial maxillae, including part of orbital floor on R and part of infraorbital plane on L. On R I 2 - M 3 are present; on L there arc broken P 1 - P 2 , and the crowns of M 1 - M 3 . Alveolus for RI1 and root of LI2. Teeth are moderately worn. Face is not very large, and the nasal aperture is narrow and pear-shaped. As seen on R, the orbital plane is forwardly facing, is shallowly concave below the medial portion of the infraorbital margin, and bulges slightly laterally on to the body of the zygoma.

56

SITE

As indicated on the R, the orbit was narrow and ovoid, and the interorbital region was apparently quite narrow. As seen from the R side, laterally the body of the zygoma protruded more anteriorly than the medial portion of the infraorbital surface (thus the posterior external surface of the zygoma faces forward and laterally). The anterior root of the zygomatic arch takes origin just above the roots of M l , and as seen on the L, it curves strongly laterally as viewed from the front. On both sides the infraorbital foramen is large and forwardly facing. O n the R the large lacrimal fossa lies behind and below the inferior orbital margin. The orbital floor is quite well excavated, with a sharp rim on to the face. The nasoalveolar clivus was quite long but strongly downwardly curved, and its posterior pole does not greatly overlap the palate, the two being separated by a short, downwardly sloping and moderately broad incisive canal. As indicated on the R, the palate was thick anteriorly and tapered gently posteriorly. The palate is deep, deepening quickly from behind the incisors, with relatively straight side walls. The incisive foramen lies below P2, and opens slightly anteriorly. Dentally this specimen is generally comparable to 200-la and 486-1, but it is smaller and differs in that both Ps are more tightly curved (and thus m/d shorter) buccally than lingually. AL 486-1. L maxilla with midline and much of frontal process. All teeth are present but the C (represented by root), and fairly unworn. Looks very much like the AL 200-la palate and teeth. The frontal process suggests that the nasal aperture was fairly narrow and pear-shaped. Posterior pole of clivus greatly overrides palate, which is quite thinly tapered anteriorly and thickens posteriorly. Thus there is a very long, shallowly sloping incisive canal between the clivus and the palate. Mandibles and Lower Teeth AL 198-1. L corpus from symphysis to just behind M3, with alveolus for I I , root of 12, and C - M 3 ; root of a fourth molar is visible behind M 3 , and there is also an interstitial facet visible on the rear of M 3 . All teeth are weathered and worn to extremely worn. This is a relatively small and not very massive mandible that is moderately tall s/i but thin m/1. The tooth rows would have been more or less parallel, and quite long and narrow. In what is preserved of the symphyseal region there is a slight depression below the root ot 12, due to bone remodeling. Otherwise the

ENTRIES

symphysis is featureless, with a fairly tio-ht across. In profile the symphyseal region appear " have been straight almost to the inferior margin J backwardly tilted. The large mental foramen Hes w U below the region of P 2 - M 1 , and the area above it between PI and the anterior root of the ramus is %h ? lowly concave. The anterior root begins to swell slightly moderately below M l , but the bone is not markably thick in the region of M3, and there is mandibular gutter. Internally, the Ion* postincisal plane slopes moderately down halfway, and then slopes gently down to the inferior margin, where it turns forward strongly. The digastric fossa extends quite far laterally from the midline, and faces posteriorly. The region below M 3 is damaged, but elsewhere there is no evidence of a mylohyoid line, and onlv closer to the symphysis is there any hint of a submandibular fossa. The bone thins to the inferior margin. It appears that there had not been an expanded internal alveolar crest. T h e 11-12 alveoli are both compressed m/d; the I I is slightly larger in all dimensions than the 12, Both I crowns were probably quite large. C is relatively small (possibly female), with a long, somewhat steep distal slope that terminates in a peaked, ledgelike short heel. The mesial side of the tooth is quite vertical, with a short superior mesial cd^c. Thus the tip appears to lean back a little. Except for a moderately thick mesial margocristid, the lingual surface is essentially flat, and its axis is slightly oblique relative to the corpus. The Ps arc too worn for detailed description. In general shape they are hcteromorphic, the PI being somewhat roundedly triangular in outline and distended distolingually. Its lingual surface runs obliquely to the m/1 "corner" of the tooth, which bears a short cristid on its lingual side, delineated by a vertical crease. Its long axis is oblique in the jaw, and there appear to be three roots. P2 appears more squared, but its axis lies along the d/l and m/b positioned roots; it may have had four roots. M l was very small relative to M2; both were apparently squared-up distalhj whereas M 3 is somewhat more elongate and rounded distally. It had a hypoconulid that straddled the midline. .* Although the teeth are very worn, the shapes o 2 P 1 - P 2 and small size of the M l particularly sugnc gest it belongs with this morph. AL 200-lb. Isolated and essentially unworn RMi» very similar in morphology to the RM1 ot -»•

If ADAM

including the d/b-jutting tiy|HH:c»riulicl that i* «riMNtrd from the large ami bulbous hvpoconid by a fairly wide and deep notch. An seen in the unworn state, none of the cusps- is compressed, the buccal and lingual cusps arc fairly widely separated toward the perimeter of the crown and the enamel bears a moderate number of short, deep grooves, AUiMhIH. RM„cf.-100-la. AL 2XS'1i, j and k. "Lucy" mandible. Consists of most of a mandible, missing both coronoid processes, K gonial region, posterior part of L corpus, and external parts on cither side of the symphyscal region. Inferior internal region of symphysis is missing. Preserves R P 1 - M 3 , with only M l showing significant wear. Roots of R and LI1, L 12, LP2 and Ml arc present, plus a root fragment of the R canine. This is a small mandible; its corpus is not tall s/i or thick m/l. Rami are not very tall, though the condyles arc relatively large. Check tooth rows diverge moderately, and the RM2 is twisted slightly lingually while the Ri\ 13 is twisted outward (impaction). Front of jaw is very narrow, and both internal and external symphyscal curves arc quite tight and more or less parallel. The symphyscal region as preserved below the incisor roots is smooth, devoid of morphology, and smoothly and strongly curved from side to side. In profile the symphyscal region bulges slightly below the Is, then curves gently down and back to the inferior margin. Seen from the front the symphyscal region tapers interiorly, being broader across the alveolar region below the canines than just above the inferior margin. The inferior margin is not elevated in front, but as seen on the R the inferior margin rises strongly posterior to M2. The large mental foramen lies well below the region between PI and P2. The bone swells gently around the buccal root of P I . As seen on both sides, the anterior root of the ramus takes origin somewhat below the mesial part of M l , and appears to expand quickly outward externally, so that there would have been a distinct bilateral bulge below the M 1 - M 2 , behind which the bone would have thinned to the gonial region. However, the internal contour of the ramal root stays close to the Ms, so there is no mandibular gutter. As preserved on the L the gonial region is smoothly and shallowly rounded, and bears some areas of muscle scarring along the margin. The condyles arc very wide m/l, but are not very long a/p. They arc slightly rounded a/p, and most of the articular surfaces are straight across, though they turn down

•">/

slightly medially. O n both sides there is a small vertical ridge prolonging the external side of the condyle. As preserved better on the R, the sigmoid notch crest becomes blunt as it runs to the lateral margin of the condyle. The sigmoid notch itself appears to have been shallow relative to the condyle, and uniformly arcuate. Internally, the postincisal plane is modcratclv long and steep. The symphysis is broken below, although the sides of a moderate inferior transverse torus arc visible at the inferior edge. As seen on the L, the shallow but long digastric fossa faces posteriorly and internally. Neither on the L nor the R is there anv sign of a mylohyoid line or a submandibular fossa. On the L, behind and under the region of M 3 , is a distinct mylohyoid groove. As seen on the L the internal alveolar crest is not enlarged around the M 3 , but there is a continuation of a low crest that runs from it posteriorly, up and back to the rear of the ramus well below the condyle. This termination is seen on both sides, and on the L the inner surface of the preserved lower region of the coronoid process is smooth. As seen on the L, the preserved internal gonial region bears a scries of discrete, well-developed muscle scars along its inferior margin. As inferred from the R side, the mandibular foramen would have been quite low; as seen on the L the mandibular canal runs anteroinferiorly almost directly behind the M 3 . The II roots are small and subcircular in cross section, and do not appear to be very long s/i. The 12 roots arc much wider b/1 and are quite compressed m/d and possibly longer than the II roots. The C roots arc quite tall and, judging especially from the R, are somewhat ovoid in section. There would have been no diastema on cither side of the tooth. Impossible to tell crown height. The Ps arc hctcromorphic; only the P2 has a mctaconid. As seen on the L, PI had two roots, whereas P2 apparently had three. Neither PI nor P2 is oriented obliquely in the jaw. PI is dominated by the protoconid, which is quite centrally placed b/l on the tooth, but lies slightly mesially. The buccal surface is quite sloping, and is curved strongly from front to back. Blunt pre- and postprotocristids are oriented directly fore ami aft. H i e shorter preprotocristid kinks lingually at its base, to form a short cingulid that subtends a small notched vertical fovea. A stout cristid runs directly lingually from the protoconid, with a modest slope throughout part of its length before it turns strongly downward, creating a distinct flexure in rear profile. The crest then runs

58

SITE

ENTRIES

arcuatcly around to the distal side where it runs up to meet the postcingulid, enclosing a large, moderately deep basin. Thus the PI is quite narrow lingually, with most of its bulk d/I, making for a subtriangular occlusal outline. P2 is slightly shorter m/d than M l , but is wider b/1. The worn protoconid and the low but distinct mctaconid opposite it lie quite mcsially on the crown. There is a small, horizontal, wedge-shaped anterior fovea at their bases. A cingulid runs d/1 from the mctaconid, then turns sharply up the distal side of the tooth to flow into the base of the protoconid, thus enclosing a large, moderately deep basin. The d/1 corner of this tooth is most swollen lingually; the buccal side is m/d narrower than the lingual side, and is quite strongly curved in occlusal outline.

tapers anteriorly. The slightly concave orbital curves back strongly onto the supraorbital marein I profile the frontal would have sloped up fairly stcc I directly from the thin supraorbital margin. The front 1 lobes apparently extended well forward over th orbital cone. This piece appears to have come from roundish skull, with few muscle markings. No sutur visible (thus this is a mature adult).

The Ms increase in length from M l to M 3 . M l is quite worn, M2 is moderately worn and M 3 is barely worn. M l is noticeably narrower b/1 than M 2 - M 3 . All have a fairly b/1 wide and centrally placed hypoconulid that looks more like a fold of enamel than a cusp and is distinguished from the hvpoconid on M 1 - M 2 by a small notch. M3 preserves a distinct, moderately lcdgclikc paracristid that may also have been present on Ml—M2.Thc enamel of M 3 is deeply and thickly wrinkled, as was that of M2 and possibly also M l . The protoconid and somewhat b/1 compressed mctaconid and entoconid are roughly similar in size and larger than the hvpoconid on all molars. In detail, though, the mctaconid is m/d a bit longer than the protoconid on M l , and becomes increasingly shorter on M2 and then M 3 . On all Ms, the very blunt base of the hvpoconid abuts that of the entoconid at the midline of the crown. As seen on M2, a deep and broad notch separates the hypoconulid from the entoconid. As seen on M3, the cusps arc peripherally placed, with a broad, shallow basin between them. This was probably also the case on M 1 - M 2 . M 2 - M 3 have a small mctastylid-like crease up against the base of the metaconid. On M3, a thick paracristid courses straight down the face of the protoconid, "kinking" at the base of the cusp and then proceeding lingually to terminate low on the metaconid; the upper surface of this cristid presents itself as an open basin. It appears that at least M2 was similarly configured.

CsandMl.

AL 2SS-lh. A small fragment of L frontal incorporating some of the medial portion of the supraorbital margin and the orbital roof, possibly extending into the region of glabella. Vault portion is thin-boned; the preserved supraorbital area itself

AL 353\v-48. An isolated, moderately worn RM very similar in size and shape to 200-lb. AL 400- J a. R and L corpora, broken more or less at the midline, lacking most of their inferior margins and both rami. All teeth present except Rll; LPl is slightly damaged; all teeth arc worn, especially the Is R part of symphysis is intact from top to bottom, demonstrating that the corpus was not very tall s/j. Corpora are also not very thick m/1. Tooth rows arc straight and diverge only slightly, and there arc fairly tight and parcllcl curves at the front, both inside and out. As judged especially on the R, the external symphyscal region bears no morphology (no inferior pits) and is fairly tightly and smoothly curved across. In profile the symphysis is straight and angled slightly backwards from top to bottom, only curving to the inferior margin well down. In front view, on the R side, the downwardly pointing and m/1 broad digastric fossa is visible, producing a distinct upward arc on the inferior margin. As seen on the R, a relatively large mental foramen lies fairly low beneath P1-P2. The anterior margin of the foramen is slightly swollen. As seen especially on the R side, the anterior root of the ramus takes origin just behind M l . The region posteriorly is broken, but the bone probably thickened m/1; as preserved on both sides, there is no mandibular gutter. T h e region between the raised foraminal margin and the anterior root of the ramus gives the appearance of being very slightly sunken. Internally, the cross section of the symphysis as seen on the R show's a very long, fairly steep and slightly concave postincisal plane that runs more than halfway down the symphysis before curving forward into a broad fossa that contains two asymmetrical!) deep pits. Below the fossa the inferior margin is thickened into a distinct but laterally short interior transverse torus. Neither side shows evidence of a mylohyoid line, and there probably was no submandibular fossa. On both sides there is no development or an internal alveolar crest.

H A DAK

Although worn, it appears the Is were fairly tallcrowned. As seen on the L, the 11-12 were narrow, but the sides of 11 are straight and slightly divergent, whereas on the larger 12 they are more flared and a little more divergent. The lingual surface of I I is smooth and not expanded toward the neck, while on 12 there arc distinct but low margocristae, and a low and broad central pillar with a shallow, narrow vertical fovea on each side. The C crowns are worn to the level of the incisors. Even so, these were tall but slender crowns. Internally, both Cs bear a very strong central pillar, and relatively strong margocristae. There is a deep, vertical fissure on either side of the pillar. There are no diastemata. P 1 - P 2 are heteromorphic O n the damaged L P 1 the protoconid and the lingual crest are not as worn, and their structure is thus more clearly apparent than on the more worn R P 1 . T h e large, centrally protoconid preserved on the intact R P 1 is quite worn. It is internally placed, creating a buccal slope to the tooth. A short paracristid runs m/1 and then turns sharply downward toward the base well before reaching the lingual side of the crown. Another crest runs lingually and almost horizontally from the apex of the protoconid, and then, as seen in posterior view, flexes strongly downward; it then runs d/1 to some extent before turning sharply up the distal side of the tooth to join the thick paracristid. This latter cresting system encloses a large and moderately deep basin. A deep, moderately large and fissurelike fovea lies between the paracristid and the lingually directed crest. Because this tooth is distended somewhat d/1 and is longer m/d toward its buccal side, in occlusal view it looks subtriangular and appears to be skewed somewhat obliquely in the jaw. T h e P2 is slightly wider b/1 and longer m/d than the P I . It is tightly rounded on its m/d quite short buccal side and is straighter on its m/d much longer lingual side. T h e large worn protoconid is somewhat mesially but not internally placed. The smaller metaconid is situated even more mesially on the crown. A small wedge-shaped fovea lies between the bases of these two cusps. A worn, thick postcingulid runs d/1 back from the distal side of the metaconid to the d/1 corner of the tooth, where it turns sharply up to meet the distal side of the metaconid. This crest encloses a moderately sized basin that may also have been wrinkled. The M l is more worn than the M 2 , which is more worn than the M 3 . M l is noticeably smaller both m/d and b/1 than the other M s , but all Ms are

59

relatively long m/d, although not very b/1 narrow. All three M s bear a somewhat deep and moderatelv open notch between the protoconid and hvpoconid and a narrower notch between the Irypoconid and the buccally placed hypoconulid; in all, the somewhat b/1 compressed metaconid is noticeably longer m/d than the more expansive protoconid. M2—M3 have a good-sized metastylid between the metaconid and m/d elongated and b/1 compressed entoconid region (not detectable on M l , although its entoconid region is also long and compressed). There is a short but somewhat thick crest on M 2 that courses d/b between the entoconid and hypoconulid; a crease in the enamel delineates the inner side of this crest and thus also the distal side of the hypoconulid; M l was probably the same. In all M s , the hypoconulid distends the tooth slightly distally and buccaUy, although the distal end of M 3 is the most rounded and broadest b/L The enamel on M 3 is thickly wrinkled, as is probably also the case on M 2 , and was maybe also on the worn M L M 3 has a short but thick paracristid. AL 417-1 a and b. l a is part of a L mandibular corpus from root of R I l through L M 3 ; l b is the superior part of a corpus containing M2—M3. Not very robust, with parallel tooth rows. Preserved are the roots of R I 2 - L 1 1 , partial crowns of L I 2 - C , and fairly worn crowns of L P 1 - M 2 ; only part of trigonid region of L M 3 is preserved. The P2 of this specimen is similar to 400-la in being much shorter m/d buccally than lingually (producing a somewhat roundedly triangular occlusal outline), with the metaconid quite mesially placed. The P I also has the protoconid-based cresting system, and the C has the deep vertical lingual grooves with thick margocristae. The M l is not as relatively small, but, although much more worn, the M 1 - M 2 preserves traces of features (e.g., slightly buccally shifted hypoconulid with a thick crest between it and the entoconid) also seen in these teeth in 400-la. The corpora were also more parallel-sided than divergent. A L 266-1 Adult Lower Dental Morph (includes AL 188-1,200-13,277-1,333w-12,333w-59) This morph is characterized by a P i with some basin development (especially distally) and a terminally unswollen protoconid crest; a P2 with very small metaconid region and some distal distension; M 1 - M 3 with an arcuately compressed hvpoconid that is always longer m/d than the protoconid, an M l

60

SITE

that is not noticcablv wider b/1 mcsially than distally, and an M2 and less so M3 that are broader b/1 mesially than distally. Apart from these characteristics, this lower dental morph is quite similar to that represented by 198-1, of which it might reasonably be considered a submorph. AL 188-1. A partial R corpus from the region of the broken PI root through M 3 . P2 and M l crowns arc broken; M2-3 are very worn. Bone very weathered. For the large size of the teeth, the mandible is quite small. It is narrow m/1 and shallow s/i. Anterior root of the ramus begins to rise just under M 2 . There probably was a modest mandibular gutter. Internally morphology has been lost, though clearly there was no internal alveolar crest and the bone did not thin dramatically to the inferior margin. PI preserves part of the alveolus for the m/b root, which is anteriorly distended. The m/b root of P2 is distended forward, and the d/1 root is distended backward; thus the tooth was oblique in the jaw. All is indecipherable, but appears not to have been small relative to M2, which is slightly narrower b/1 and more noticeably shorter m/d than the M 3 . M 2 - M 3 are very broad mesially (M2 is broader mesially than distally), and the M2 is rounded distally. M 3 was rounded and tapered somewhat distally, and was longer m/d than the M2. Although quite worn, some occlusal morphology is still visible on these two molars. On M2 the metaconid is noticeably m/d longer than the protoconid, but is less so on A13; on each, this cusp is slightly b/1 compressed. Also on each, the blunt and m/d long base of the hypoconid, which is well-delineated both fore and aft by grooves, extends just across the midline of the crown to make a small contact with the metaconid and a longer one with the somewhat b/1 compressed but otherwise relatively large entoconid. On M2 the small-moderate and very buccally placed hypoconulid angles almost lingually to contact the entoconid; there may have been a small shelf distally between these two cusps. On M 3 , it appears that the moderate hypoconulid is wedge-shaped and situated in the midline of the crown. AL 207-13. L corpus lacking ramus and extending around to the region of the RC. Alveoli for R I 2 - L C are present, and the jaw contains P 1 - P 2 and M2 and the somewhat worn and broken M l and roots of M 3 . Medium-sized jaw, badly crushed and weathered. Somewhat tall s/i and moderately wide m/1. It appears

ENTRIES

that the tooth rows were not very divergent and that the symphyseal region, inside and out, was very tightly curved. Externally, the symphyseal region lacked detail and was narrow from side to side. In profile the symphysis curves smoothly down and back to the inferior margin. T h e possibly large mental foramen lies well below P2; the anterior root of the ramus begins to bulge behind M 1 - M 2 and continues widening posteriorly. There is evidence of a fairly wide mandibular gutter. Internally it appears that the postincisal slope was long and quite steep, to about halfway down the symphysis. It is broken below, but inferiorly the margin appears to be thickened. The region of the digastric fossa is damaged. There is no sign of a mylohyoid line or of a distinct submandibular fossa; the bone thins posteriorly. Judging by the alveoli the stout I roots were quite compressed and wide b/I, but not very long s/i. As seen better on the R, the C root was stout, compressed, and very wide b/1. Although smaller, the PI is essentially comparable to that of 266-1, though the m/b root is not as forwardly displaced. P2 is much bulkier than P I . Morphologically it is similar to that of 266-1, though the d/1 corner of this tooth is delineated by creases in the enamel, as if it were a cusp. T h e preserved M 2 is moderately long m/d, with a b/1 wide, centrally placed hypoconulid and somewhat sloping buccal sides with somewhat internally placed buccal cusps and a long, narrow, lingually shifted talonid basin. As in 266-1, the entoconid is quite small. T h e M l may have been slightly shorter m/d than M 2 . M 3 narrows distally, where it was probably rounded. AL 266-1. Partial mandible, with corpus from L M l to R M 3 . Missing some alveolar bone from the front of the jaw; alveoli only present for L - K C Preserved on L arc P I - M l ; on R, P 1 - M 3 . Teeth moderately worn, M l the most. Quite weathered. Moderately large but not massive mandible. Fain) wide m/1, but not very tall s/i. Check tooth rows are slightly divergent, and internally and externally the smooth curves across the front of the jaw arc qui c tight. The preserved inferior part of the symphyses region is smooth from side to side, and in profile tne symphysis curves back and down to the inferior mar gin. The mental foramen is damaged on the R; on t L it is large and lies very far below PI. Anterior to and above it there arc three small foramina. Below t foramen the bone is slightly depressed. As seen on t

II A DA R

o the anterior root of the ramus begins to swell liVhtlv below the distal part of M l , and the bone -ontinues to thicken posteriorly. The preserved infc- f p i r t of the anterior root of the ramus is separated from M3 by a reasonably well-developed mandibular gutter. Internally, what remains of the postincisal plane is quite inclined; from halfway down the mandible the internal symphysis curves smoothly down, around and forward to the inferior margin. There arc no genial structures; digastric fossae, mylohyoid line or submandibular fossa are not visible. There is no evidence of expansion of the internal alveolar crest. The 12 and probably II roots were strongly compressed, the lateral probably larger than the central. The C alveoli would have housed quite massive, compressed but not very tall roots, and the Cs would have been only slightly obliquely placed in the jaw. Both Pis have three distinct roots, the m/b one being displaced forward and the lingual one distally, so the tooth is quite skewed in the jaw. The sloping buccal side is also distended over the m/b root. A short, thick cristid courses lingually from the somewhat centrally placed protoconid apex, maintaining a fairly high position on the crown before turning down; a steep, vertical, distal "walT descends from it. A thick but shorter paracristid descends almost straight down the mesial side of the crown and encloses a moderately deep but small and lingually facing fovea or basin. An equally short postcingulid courses even more directly down the distal side of the tooth, and then swings sharply buccally to terminate alongside the base of the "wall" associated with the lingually directed cristid; the postcingulid encloses a more expansive and distally and upwardly facing talonid basin. In occlusal profile, the P i s are roundcdly triangular. There arc thin pillars mcsially and buccally on the buccal sides of the teeth. The P2s are bulkier than the P i s ; they arc longer nvd on their lingual side than on their more tightly curved buccal side. The worn, mcsially positioned protoconids would have been taller than the large mctaconids opposite them; the bases of these cusps arc somewhat melded. An apparently thick paracristid descends fairly strongly down the mesial side of the tooth, turning sharply buccally and then coursing up to the apex of the metaconid; at best it encloses a very small anterior fovea. A thick postcingulid runs from the distal side of the protoconid, down and around the d/1 expanded part of the tooth to terminate at the base

61

of the metaconid; it encloses a modest basin. There is a distal pillar on the buccal side of the tooth. The M l is smaller, especially b/l, than the M2L M 3 is the longest m/d of the molar series. M2 is unusual in being wider b/l mcsially than distaik All three Ms bear well-developed, fairly buccally placed hypoconulids that slant mesially and lingually to contact the smallish, somewhat b/l compressed entoconids; a distinct shell* between these two cusps enlarges in the sequence M 1 - M 3 . The b/l compressed metaconid is noticeably longer m/d than the protoconid on M l , but becomes relatively smaller on M2 and then M 3 (although it is still longer than the protoconid on M3). This cusp arcs around the no/1 "corner'" ot the tooth on all Ms and its inner surface is somewhat vertical (more so on M l , and least on M3X As best seen on M3 the not very thick paracristid courses in a downward arc between the apices of the protoconid and metaconid, enclosing a very thin, creaselike trigonid basin. The paracristid is thick on M2, as it may have also been on M l . T h e hvpoconid is compressed and welNdclincatcd by grooves fore and aft on M 2 - M 3 (probably also on M l ) . Its somewhat blunt base comes to the middle of the crown, making short contacts with both the metaconid and cntoconid. M 2 - M 3 have some enamel wrinkling (suggesting that the same was true for Ml).There is also a hint of buccal cingulid on M2, between the protoconid and hvpoconid, and a distinct notch between the hvpoconid and protoconid on M L At least on M3, the buccal side of the tooth is quite sloped, and the long, shallow talonid basin is somewhat lingually shifted. AL 277-/. L corpus from the symphysis to just behind M2. Preserves partial alveoli for the 11-12; C - M 2 are present, and all teeth are very worn and some arc damaged. Moderately large jaw, but not very massive. Fairly deep s/i for the length of the tooth row, and only moderately thick ni/1. External surface of the symphyseal region has been flaked oil* but the inferior portion is preserved and curves smoothly to the inferior margin. Front of the jaw was apparently moderately curved across. Mental foramen is moderate and lies far below P 2 - M 1 . A tiny foramen lies further up, directly below P2.The anterior root of the ramus begins to swell at M 1 - M 2 ; the bone is broken behind. The cross section of the symphysis shows a fairly strongly sloping postincisal plane that was probably relatively

62

J>!TE E N T J < M : S

long. About a third of die way down the corpus, in die region of P2, die profile drops down into a broad fossa that contains a large and deep pit. Below, die bone swells gently to a wry mild inferior transverse torus, then forward to die inferior margin. Running down from the fossa is a pair of diin, long crests. T h e digastric fossa is quite long and faces downward (creating an upward curve to the inferior margin when the jaw is viewed from the front). There is no mylohyoid Jine, and there is at best a very small submandibular fossa low down and close to die genial pitBoth incisor alveoli arc short-rooted and compressed laterally (the central more so) and are similar in b/1 width. The somewhat obliquely oriented C has a moderately stout, tall root that is somewhat compressed m/d. The crown was narrow, and possibly quite tall, with a shallow distal fovea low down on the lingual surface. P 1 - P 2 are heteromorphic P I is roundedly subtriangular, with a somewhat m/d long, strongly curved buccal side and a much b/1 narrower lingual side. T h e somewhat centrally placed apex of the protoconid is also rather internally situated, so the buccal side is quite sloped. There is a shallow, "wedgeshaped vertical depression on the buccal side of the cusp, somewhat mesially positioned A stout but very short paracristid curves lingually around the front of the tooth, enclosing a tiny, m/1 facing and almost vertically oriented basin. A vertical crease delineates the lingual extent of this crest. A much stouter and longer crest runs lingually and slighdy mesially from the protoconid and down to the lingual edge of the tooth. A distally directed crest turns lingually at the distal edge of the tooth, and runs around the lingual portion of the crown to enclose a modest and somewhat vertically oriented lingual basin. P I may have had only two roots, and is only slighdy obliquely set in the jaw. The bulkier P2 is narrower b/1 than the P I ; it is longer m/d on the lingual side than on its more tighdy curved buccal side. A modest metaconid lies across from the large and rather mesially positioned protoconid. A thick cristid ran distally from the side of the protoconid around to the side of the metaconid, swelling out the tooth d/1 and enclosing a modest basin. This tooth appears to have three roots, two lingually. M l is damaged, but was smaller in all dimensions than ^12. However, both teeth are wider b/1 across the mesial half than across the distal half of the crown. M 2 is slighdy rounded distally, with some distension d/1. The protoconid was somewhat short m/d, but was b/1 wider than the slighdy m/d longer

metaconid. The metaconid appears to h around die m/1 portion of the crown, and its i ^ faces are somewhat vertical. Trie fcypocxmulid' ^ small, and may have been somewhat centrally bkir IT AL 333W-J2. Fragment of R corpus from ' lateral of midline through the region of M2 V - • * very worn M l and roots of 12, etc. Corpus i s ^ i * shallow s/i, and moderately thick. Cheek tooth ' would have been fairly divergent, widi a moderate symphybeal curve internally and externally External! the symphyseal region is featureless except for a slight depression in the region around the root of 12. In profile this region curves down and back to the inferior margin. T h e large mental foramen lies wd below P2. Internally it appears that the postinrisal plane was of moderate length, a little concave and moderately sloping. It curves about halfway down into a shallow fossa, below which the bone swells as it curves down and forward into the inferior margin. T h e very long but shallow digastric fossa produces 2 long but shallow upward curve to the inferior margin when viewed from the front. There is no evidence &Ii mylohyoid line, but there is a small, shallow submandibular fossa under the region of M l . From the tooth roots it appears that P i was slightly skewed; P2 was not. T h e very worn M l is short, and b/1 wider mesially than distally. AL 333w-59. Very crushed piece of L corpus, wirh verv worn and cracked M 2 - ^ B . HvpoconuHd ot moderate size on both molars, just buccal to midline Mesial part of tooth wider than distaL A L 333w-60 Adult Lower Dental Morph (includes A L 128-23,145-35,207-13,330-5,366-1,333w-la and b, 411-1) This morph is characterized by an ocdusally lesstrr angular P I with a more lingually thickened and! hon zontal protoconid crest (which is actually ^ J " * . . 333w-la), a P2 with a moderate metaconid *** a ^ tincdv roundedly distended d/1 region, M 1 ~ - b * ^ some'buccal cingulid and very b/1 ^ ^ ^ p ^ . * , conid and entoconid regions, and at least an ^ distinctive notches between the protoconid hypoconid and the hypoconid and hypoconubd. AL 128-23. R mandibular corpus lacking ra*»* and much of its symphyseal region, * ™^p ^ inferior margin posteriorly. Preserves RC - ~ ^ damaged RI2. C crown partially broken. Slight *-

II A DAK

63

1 j

on all teeth except M l , which is more worn. Some cracking. Fairly small but s/i deep jaw, moderately wide m/1. Tooth rows would have been strongly divergent and the jaw narrow at the front, probably with tight inner and outer symphyscal curves. External profile is impossible to tell, but the bone curved back in strongly at the lower margin. The large mental foramen lies well below PI; the anterior root of the ramus rises below the distal end of M l and is thickest m/1 by the M2, behind which the bone becomes thinner. As seen from the preserved inferior portion the anterior margin of the ramus slopes back strongly, and is separated from M2 and the region of the missing M 3 by a moderate mandibular gutter. The bone preserved behind the anterior margin is somewhat excavated. Internally, the symphyscal region is broken close to the inferior margin, which is thickened, possibly into a torus. In the region of the 12 the postincisal plane is very steep. A moderately excavated and downwardly pointing digastric fossa creates an upward curve in the inferior margin, under the region of the 12 and C. There is no trace of a mylohyoid line, but there is a very shallow submandibular depression near the inferior margin below P 2 - M 1 . Behind the M3 is a trace of a mylohyoid groove. There was no development of an internal alveolar crest. The stout, b/1 wide 12 root is very compressed m/d, and not very long s/i. The preserved C crown is rather slender and was probably quite tall, with a long, fairly vertical mesial slope and a slightly longer steep distal slope that expands into a slight heel. The lingual surface is essentially flat but for a low, broad mesial margocristid.The P i has a distended d/1 portion. The short, thick paracristid kinks lingually, where it is delineated by a vertical crease. It subtends a shallow lingual fovea. A stout, essentially directly lingually oriented crest emanates from the protoconid. A thick postcingulid, which emerges low on the crown at the terminus of the fairly steeply descending postprotocristid, arcs lingually and up to meet the lingual protoconid crest, enclosing a relatively large and deep talonid basin. This we describe elsewhere as the "Tshaped" configuration. There is a strong buccal slope, but no anteriorly emphasized m/d root. The bulkier P2 is longer mesially, shorter and rounded buccally, with subequal and mesially placed protoconid and metaconid, a modest mctaconid apprcsscd to the protoconid, and a thick postcingulum that swells the tooth d/1 and encloses a moderate basin. M 1 - M 2

have some buccal slope and arc roundedly rectangular; the M l is only slightly smaller, especially b/1, than the M2. Both molars have compressed buccal cusps, m/d long, b/1 narrow and somewhat lingually shifted talonid basins, and hypoconulids that lie slightly buccal to the midline. The enamel of the talonid basin of M2 is slightly crcnulatcd. These Ms differ from the others in their potential group in having distinct and d/1 situated fovcac, with a thinner crest behind that connects the cntoconid region with the hypoconulid. AL 145-35. Part of a L mandibular corpus from the II alveolus to M2, missing most of the symphysis. Preserved are alveoli for I I - C , root of P I , damaged P2, and M 1 - M 2 . Corpus is very shallow s/i but is relatively thick m/1, and short. Corpora would have diverged somewhat strongly, with the check tooth rows being bowed and curving back slightly posteriorly. The bone of the symphyscal region is smooth where preserved, just lateral to the midline. The jaw would have curved broadly across the front, bulging around the region of the canine root. The front of the jaw probably tilted slightly back. A moderate mental foramen lies not quite halfway down the jaw below P 1 - P 2 , on the side of the canine bulge. More distally, the bone appears concave by comparison. The anterior root of the ramus begins to bulge outward slighdy below M l , and widens the jaw considerably by M2. The corpus thins again behind. The corpus thins strongly to its inferior margin, and internally shows no sign of a mylohyoid line or a submandibular fossa. A trace of the backwardly facing digastric fossa is preserved, extending quite laterally below the region of P2. The I alveoli arc very compressed. The C alveolus is wide b/1 and quite compressed m/d; the root would have been relatively tall compared to jaw depth. PI was apparently two-rooted at most; its roots were strongly compressed m/d, and it is moderately obliquely set in the jaw, with some d/1 distension. P2 was three-rooted at most. It was a bulky-crowned tooth, longer m/d on the lingual side than the buccal, with a small metaconid apprcsscd to a somewhat mesially shifted protoconid. There is a distinct, mesially positioned metaconid. The d/1 portion of the crown is swollen by the thick postcingulid, which encloses a fairly large and moderately deep basin. M 1 - M 2 arc relatively long m/d and narrow b/1. There arc notches between the protoconid* and hypoconids, and between the hypoconids and slightly

64

SEIE

buccillr shifted hjpocomifids, the hzzct 2 bit Larger thin the former. There is cingulid 2: the base of the mesial notch on M2 and at the base of the distal notch on M L There are b/I narrow but m/d-thick paracristids. The buccal cusps are somewhat centrally placed, and the buccal sides are somewhat swollen. The metaconid and entoconids are m/d elongate and rather b/1 compressed. The protoconid is much m/d shorter than the metaconid on M l , less so on M 2 . A thick distal crest connects the cntoconid and hypconulid on both Ms. The talonid basins are long, narrow, shallow and somewhat lingually positioned. M 2 has a small, wrinkle-like mctasrylid at the base of the metaconid, and some buccal cingulid around the protoconid. There may have been a buccal cingulid on M L Both molars probably had some wrinkling. AL 207-J. Partial L corpus including most of the front of the jaw; preserves complete but somewhat worn crown of LP1, P2, and M2, broken crown of M l (only some of the buccal portion of the surface remains) and the base of the crown of M 3 . T h e symphysis was relatively thin a/p and was almost V-shaped and narrow across at the front, although the check tooth rows were more parallel than divergent. The postincisal plane is very tall s/i and fairly vertical, terminating midway down the internal symphyscal region at a low horizontal swelling that continues the rather thickened and prominent mylohyoid line; the symphyscal region below is more vertical. There is a thick internal alveolar crest running alongside the entire check tooth row. In general the P2 is the most similar in detail to the other specimens in this group, although the Pi and the relative sizes of the Ms are also consistent. The preserved M2 is more distended d/1 than that in 333w-60, but the cntoconid regions can be compared in detail (e.g., b/1 compression, m/d length, including the patterning of grooves). AL 330-5. Damaged primarily R mandibular corpus from region L C - R M 3 , preserving the crowns of R P 2 - M 3 . This jaw is fairly bulky m/1 with somewhat divergent tooth rows. The shape of the base of the crown of the damaged PI is consistent with this tooth in 333w-60 and especially 207-13, and the P2 is virtually identical to the P2 of 207-13. M 1 - M 3 arc m/d long and b/1 narrow and of similar size relationships to those in 333w-60. M 1 - M 3 have a deep protoconid-hypoconid notch, as in 333w-60, but with thick cingulid below (at least preserved on M3 of 333w-60). M l lacks the distinct

EMRIIS

Inroo^rikl-inTOCOBuIid rx>:cfo of 533TTH6*0I K-* J. M3s are similar In this record. T h s srev-mr<~~ similar to 333w-64) in having -in mM hr?y *-A V « compressed cntoconid resxKi (with crwwes ©Q A „ inner surface on M 3 h the M 2 oi* 207-13 ii«o se^n*. similar. Molar talonid basins are lone, K'l rurro^T *r.4 somewhat lingually shitted (c£. 3 3 3 W H 6 0 and 207-13]i AL 366-1. A n isolated L M j , a bit worn. Sauath and roundedly rectangular, with tairly bulbous cu>->L except for the somewhat compressed and araiatthoriented metaconid. This tooth is quite similar to the M l in 266-1. AL 333w-la and b. Mandibular corpus fragments. l a is L side, with P 1 - M 2 ; l b is R side with P 2 - M 1 They are described together below*. Corpus quite massive, relatively deep s/i, and wide m/1, especially around the region of M2. On both sides the large mental foramen lies halfway down the jaw below P2. Below M l the bone gradually swells to the root of the ramus, which is not clearly distinct. Internally there is no sign of a mylohyoid line, but the corpus narrows interiorly. M i s are moderately worn; the other teeth slightly. P i is somewhat elongate m/d and narrow b/1. It is fairly bulk)' with a very bulbous, centrally placed protoconid, and an only slightly smaller metaconid just mesial to opposite it. A very thick and relatively long, rounded paracristid runs straight forward tor sonic distance before curving quite strongly back to the base of the metaconid, enclosing a fairlv large and deep anterior basin. T h e stout postprotocristid descends from the apex of the protoconid, and (as a postcingulid) arcs around the distal side to terminate slightly on the lingual side of the base of the metaconid. It swells the tooth distally and encloses a b/1 wide but not very m/d long basin, of moderate depth. In outline the tooth is roundedly triangular. On the buccal surface are a thin mesial and thicker distal pillar, and the mesial and distal edges arc subequal in length. T h e P2 is also chunky; it appears slightly wider b/1 than P I , but is shorter m/d. The subequal, somewhat mcsially placed protoconid and metaconid he opposite each other. There is a moderate fovea in the front (enclosed by a somewhat mcsially arcing paracristid). A thick, more arcing postcingulid runs from small metaconid on the side of protoconid to distend the d/1 corner of the tooth; it terminates on the distal side of the metaconid and enclosing il slightly larger and deeper talonid basin. M 1 - M 2 arc

HAD A K

roundcdly rectangular and relatively elongate. They have distinct and fairly open notches between the protocoled and hypoconid, and smaller but still distinct notches between the hypoconids and hypconulids. The protoconid on each M l is much shorter m/d than the metconid; the protoconid is relatively longer on M2. There are short but distinct cingulids around the bases of the protoeonids. The tip of each wedgeshaped hypoconid crosses the midline of the crown and nestles between the bases of the somewhat b/1 compressed and m/d elongate mctaconid and entoconid. The long talonid basin lies a bit lingually. The hvpoconulid is large on M l , smaller on M2; on both teeth this cusp lies a bit buccal to the midline of the tooth and a stout crest runs between it and the entoconid. Buccal cusps are slightly internally placed, and the talonid basins are long and shallow. M2s show a slight, b/1 wide but thin anterior fovea, and some enamel wrinkling.

65

AL 333w-60. L mandibular corpus with some symphysis around to the region of RC. Damaged and weathered; retains worn LP1—M3, broken R J 1 - R C and alveoli for LI1 —C. This is quite a bulky jaw, deep s/i and relatively wide. The cheek tooth rows were probably strongly divergent and the symphvseal region quite wide with a marked curve around the front. Externally the symphvseal region lacked morphology, and in profile was apparently smoothly curved down and back to the interior margin. The large mental foramen lies far below R2, and the anterior root of the ramus begins to bulge outward well below the distal part of M l , and probably had swelled the jaw out considerably by M3. The mental foramen appears to lie in a very large, shallow depression. Internally, the probably quite short postincisal plane is very steeply sloped until about halfwav down the jaw, where it curves forward strongly; the bone is missing beneath. Quite close to the inferior margin, in the midline, is a broad tossa containing two deep pits separated by a •vertical keeL No evidence is preserved of a digastric fossa. There is no mviohvoid line, but the bone of the corpus thins markedly inferiorly, below a long, horizontal submandibular fossa. There is no expansion of the internal alveolar crest.

m/d. Judging by the L alveolus and the R damaged root, the lower Cs had very stout and compressed but not very long roots. Both LPs are somewhat more emphasized in m/d length than b/1 width. The LP1 is skewed slightly b/1 in the jaw; it is somewhat distended in its d/1 corner by the terminus of the postcingulid, but is not strongly triangular in occlusal outline. Its buccal side is sloped, and three crests emanate from the centrally placed protoconid. A horizontal lingual crest runs from the apex of the protoconid slighdy medially before cornering down in posterior view. The preprotocrista encloses a small but deep mesial fovea; distallv, a larger talonid basin is enclosed by a relatively thick postcingulid. These mesial and distal crests are quite thick near the protoconid, and thin as they descend lingually to the sides of the base of the thick horizontal crest. There is no mesial displacement of a buccal root. The much more worn P2 is slighdy bulkier than P I , but is not appreciably larger m/d or b/1; it is roundedly distended d/1 (by what had been the d/1 arcing postcingulid), and is slighdy longer m/d lingually than buccally, where its surface is tighdy curved (because of the postcingulid). There is a moderate talonid basin, and the fairly mesially situated protoconid is worn lower than the large metaconid opposite it. All is only slighdy smaller in both dimensions than M2, which is slighdy larger than M 3 . All appear quite long m/d and narrow b/1, and bear a fairly deep and distally opening notch between the large protoconid and hypoconid (large on M 1 - M 2 ) . A smaller notch (best seen on M l and M3) lies between the hypoconid and the somewhat small hypoconulid that lies just buccal to the midline and distends the tooth distally a bit in that region. On all Ms the metaconid is very long m/d, but is also very compressed b/1, as is the region of the entoconid on M 2 - M 3 (it was probably the same on the worn M l ) . The compression of the lingual cusps, as seen on M 2 - M 3 , shifts the very m/d long and somewhat b/I narrow talonid basin lingually. The inner surface of the elongate and compressed entoconid region bears a series of vertical grooves, which suggests that the enamel surface had been wrinkled to some degree (as probably were M 1 - M 2 ) . The molar buccal surfaces are slighdy swollen and the buccal cusps arc slightly internally placed. The distal side of M 3 is broadly rounded.

AH teeth are quite worn except for the M 3 , which is 1 little less so but is chipped at the back. The Is had stout, compressed roots. A RI2 lingual crown fragment is adherent; it is relarrveh' tall, and quite broad

The larger and more robust PI and C of AL 2771 mav reflect sexual dimorphism between this specimen and, for example, 266-1.

* ^ "*« w J . Ju.. v _ J W - V

06

Sin;

AL 4U-L Posterior part of a R mandibular corpus, with a tiny part of the ramus. M I - M 3 arc broken. Bone is heavily cracked and weathered. This is a relatively small and gracile mandible, and the region below M 3 is very shallow s/i. The anterior root of the ramus begins to swell out behind M l , and the preserved anterior margin is steeply sloping backward. There is only a ven* tiny mandibular gutter, and apparently no internal alveolar crest development. All Ms were apparently narrow, M l being more tapering and rounded distally. M3 preserves the lingual part of a cuspidated hypoconulid region, with a small cuspulid up against the m/d narrow and b/1 truncated entoconid. There is a moderately well-developed notch between the hypoconid and protoconid, and a smaller one between the hypoconid and hypoconulid. AL 333-43 Juvenile Lower Dental Morph It is possible that the morphology of the dm2s of these two specimens (especially in the configuration of the hypoconulid and fovea or depression distally) links them to the 333\v-60 adult morph. However, at this point, it seems preferable to describe them in a separate category. AL 333-43A and B. AL 333-43B is part of an immature R mandibular corpus and ramus from the region of the di2 alveolus to the back of the damaged ramus. For a juvenile the corpora arc quite robust, being especially thick m/1. The tooth rows would have been very divergent, and the front of the jaw not very narrow. The large mental foramen lies well below d m l , and there is a small foramen above it. The ramus is quite tall, and its anterior margin is strongly sloped back. The gonial angle is broadly rounded, and bears some marginal scarring externally. The a/p long and apparently bluntly rounded coronoid process towers over the coronally very curved condyle. The a/p narrow sigmoid notch lies close to the condyle, and the sigmoid crest had run to its lateral side. Internally, there is no notable morphology of the corpus, but a moderately stout pillar runs down the internal side of the coronoid anterior to its midline. A section of the developing 12 crown is seen in the bone; it is quite tall. The di2 and dc alveoli are matrix-filled, dml is much smaller than dm2, especially b/1. The cusps of both teeth are rather conical. The dml is small and relatively m/d long but b/1 narrow, and is elliptical in occlusal outline. It has a rather stout, anteriorly directed paracristid that runs down

KNTUIKS

the face of the very b/1 compressed protoconid and kinks back sharply to the base of the more euspliLP metaconid that lies slightly behind but otherwise vcrv close to the protoconid. There is a vertical, moderately deep, and m/1-facing basin. The somewhat compressed hypoconid and entoconid arc smaller titan the mesial cusps and lie at their bases. There is a smaller hypoconulid just lingual to the midline of the tooth The talonid basin is moderate in size and depth and is incompletely enclosed by a cresting system. The buccal side of the crown is swollen, especially mcsially The m/d quite elongate anil b/1 narrow din2 has a large trigonid basin that is surrounded by a cuspulatcd paracristid in front, ami a low crest behind connects the widely separated protoconid and metaconid. The former cusp is quite crestlike, while the metaconid is only somewhat compressed b/1, with a moderately bulbous metastylid behind. The moderately sized hypoconid and entoconid lie at the bases of the structures in front. The slightly smaller hypoconulid is rather rectangular in shape and lies quite buccally, its base extending just across the midline to contact the entoconid, from which it is separated distally by a broad shelf-like notch. The talonid basin is constricted and only moderately deep. A L 333-43A is part of a L corpus from dml to the anterior root of ramus. The preserved dml-dm2 are cracked. T h e bone is cracked and weathered. 1 he general proportions of the bone and teeth are similar to 43 B, but this specimen appears to be from a larger individual. A L 444-2 Morph (also includes AL 333-84) AL 444-2. This is conceivably assignable to the 266-1 adult lower dental morph because its PI was not simply triangular in occlusal outline, its P2 was a bit distended distally and its M^ was apparently broader b/1 mesially than distally. I lowever, the lower teeth are so damaged and incomplete that at this point it seems more prudent not to make this association. This is a large partial skull in seven pieces, mostly reconstructed, plus some some dental fragments. somewhat distorted and weathered. 1 he p»ir frontal is relatively thick-boned. . Frontal. Preserved is most of the body oi t ic frontal, with portions of the supraorbital regions am orbital roofs. I Iolding this specimen with the orbital roofs nor^ izontal and the preserved lower part o( the " °

II ADAH

crest vertical, the profile is quite high-domed, appearing to rise directly from the flat supraglabellar region. The supraorbital regions are not preserved fully laterally but from what is preserved the rather concave orbital roof descends anteriorly to angle back bluntly on to the flat and slighdy posteriorly tilted supraorbital surface. The superior margin of this surface is formed by the very marked superior temporal line, which runs quite medially as it curves up and back toward the midline. Thus the supraorbital and supraglabellar surfaces arc incorporated into a frontal trigone. From above, the relatively undistorted L side presents a broadly deep postorbital constriction. In coronal section the frontal dome curved smoothly from side to side. The superior orbital margins thicken laterally, and bounded what was probably a wide interorbital space. Internally, the frontal lobes did not extend significantly over the orbital cones. Nasal Bones. There is a fused fragmentary pair of nasal bones, bearing a very strong central keel and indications that the nasal bones themselves curved outward away from the keel. Zygomata. There is a R partial zygoma preserved lateral to the infraorbital foramen, medial to the zygomaticotemporal suture, and inferior to the zygomaticofrontal suture, with no contacts preserved. It is very massive, tall s/i and extraordinarily thickened along its inferior margin, which bears deep, pocketed masseteric impressions. The malar tubercle is tall but low, and quite sharply defined. T h e lateral wall of the orbit flows roundedly out on to the preserved portion of the frontal process. The inferior margin of the orbit is more clearly defined by a low edge. The preserved orbital margin is subcircular, suggesting that the orbit as a whole might have been fairly ovoid. The temporal fossa appears to have been quite capacious anteriorly, with a deeply excavated posterior zygomatic surface. The maxillary sinus did not extend very far into the body of this bone, probably no further than the lateral margin of the orbit. The bone thickens toward the frontal process and even more so toward the inferior margin. In trying to position this specimen relative to the frontal, it appears most likely that it was fairly vertical and did not bow enormously laterally. Maxilla. Crushed and distorted, preserving inferior nasal margin and part of floor of nasal cavity. In situ: U l , broken L I 2 - P 1 , P 2 - M 3 . On R in situ is C, root °f P i , broken P2 and M 1 - M 3 . Both M i s are enormously worn; the other teeth are merely heavily

67

worn. The tooth glued in the position of RI1 appears to be a LI1. There appears to have been a long and not very wide palate and the tooth rows are straight rather than bowed, though crushing makes it uncertain exactly what form the dental arcade originally took. The base of the nasal aperture was probably only moderately wide. The floor of the nasal cavity flowed out onto the clivus smoothly on cither side of the pair of raised and a/p long but not anteriorly projecting anterior nasal spines. As seen better on the R, the lateral portion of the nasal floor descended smoothly but steeply from front to back. It appears there was some drop from the posterior extremities of the spines to the floor of the nasal cavity. As seen better on the L, the facial surface of the lateral margin of the nasal aperture is flat and almost forwardly facing. On both sides a distinct C pillar (amounting to the bulge of the C roots) fades out below the inferior nasal margin. Lateral to the pillars the contour of the maxilla turns quite sharply back. Set posterior to this "corner," as seen on the L, the anterior root of the zygomatic arch takes origin well above All and faces forward. From the front it appears that the inferior margin of the anterior root curved laterally outward. O n the undistorted L side the relatively long nasal clivus curves slighdy inward down below the nasal margin, then curves out and down following the contour of the incisal roots. The nasoalveolar clivus probably curved slighdy from side to side. The maxillary sinuses extend posteriorly beyond the M3s. As seen better on the L, the sinus is subdivided along its floor by low transverse ridges. It appears that the palate was relatively shallow anteriorly, moderately deep below M l - A 12 and shallowed somewhat behind M 3 . Its lateral walls are quite vertical. The LI1 is too worn to assess its proportions, though it was thick b/1 and lacks and visible Ungual elaboration. The preserved and exposed root of the broken 12 appears much smaller than that of I I , suggesting a smaller crown. The C roots are very stout and long; the partially presened crown of the RC is thick at its base, but is too worn to assess its height. A small mesial fossa is preserved lingually. Judging from the preserved roots, PI was probably at least as wide b/1 as P2, but was apparendy somewhat shorter m/d. The better preserved LP2 has a centrally placed paraconc, and the protoconc seems to have been mesially shifted. This tooth is more tightly curved

68

SITE

m/d buccally than lingually. The molars appear to increase slightly in b/1 width, but more markedly in m/d length, from M 1 - M 3 . The metaconc becomes reduced in size in the same sequence, but the hypocone increases in size, especially distally. Thus the molars become more trapezoidal from the rectangular M l through M3. On all molars there is one notch on the buccal side, between the large paraconc region (which is distended buccally beyond the metaconc region on all Ms) and the metaconc region. The notch also indicates that the postcingulum emerged smoothly from the side of the metaconc, not from a distinct stylar region. The increased distension of the hypocone region from M l to M 3 indicates that the postcingulum became increasingly thicker and more prominent in that sequence. A notch visible on the lingual side of at least one of each of the three Ms, toward the midpoint of the crown on M 1 - M 3 and a bit more distally on M3, represents the "boundary" between the protoconc and the large but not as lingually distended hypocone. On M 1 - M 2 the hypocone was confined to the region directly opposite the metaconc, while on M 3 it extended farther distally than the metaconc. Portion of Skull Wall or Roof. This piece has been identified as part of the L parietal with some occipital and a tiny part of the squamosal attached. It appears to preserve part of the posterior extent of the L temporal line, continuous with the trace of line preserved on the large cranial base portion. Approximating these two specimens suggests a fairly globular braincasc. Otherwise no notable external or internal morphology is preserved, apart from a claimed meningeal trace. A small reconstructed piece associated with the L parietal has accordingly been identified as a fragment of R parietal. In reconstruction this fragment has been interpreted with a thick, raised temporal line that reaches the midline. Lateral to this, the bone thickens unexpectedly, suggesting that its association may not be entirely secure. Large Fragment of Posterior Cranial Base. Consists of a portion of the R parietal and the inferior parts of R and L temporals, as well as much of the occipital. The R and L temporals preserve large portions of the zygomatic arches. As seen on the less distorted R side, the body of the zygomatic arch was very tall s/i but thin m/1 and somewhat vertically oriented, twisting only at its most posterior extent to flow into the a/p moderately long, strongly laterally projecting and shclflikc

ENTKIKH

posterior root. Seen from above, the postcrio gin of the root fans out laterally and forward"121* continuation of the shclflikc suprameatal ** which in turn flows from a low but tall supra ^ toid crest that is delineated below by a fairly H **" a/p long, horizontal depression. As seen best on th' R, the very m/1 wide, a/p short and moderately dee* articular fossa is obliquely oriented and extends 1 ^ crally under the posterior root of the zygomati" arch. Medially the fossa is closed off by a poster medial lipping of the temporal. Posteriorly the wall of the fossa is formed by the cctotympanic, and laterally by a distinct postglcnoid plate. Only laterally is the fossa bounded by an articular eminence which takes the form of a low and almost barrelshaped swelling that lies fully under the posterior root of the zygomatic arch and is laterally delineated by a very sharp margin. Medial to this eminence the bone is concave from side to side. The relatively small carotid foramen appears to have pointed down, and the body of the petrosal is flexed anteriorly relative to the short ectotympanic tube that terminates in the very large, ovoid meatus that is also seen on the L. There is no discernible vaginal process on either side. Bilaterally, in the region where the tube projects from the body of the pet~ rosal, and antcromedially at the base of the mastoid mass, is a depression. It is plausibly a stylomastoid foramen, and the pit may have lain medial to it. O n both sides the mastoid processes are strongly swollen outward at the level of the auditory meatus. As better preserved on the R, the swelling is highlighted by a groove above it. The posterior part of the groove is overhung by a slight shelf of bone. As preserved, this latter shelf of bone proceeds laterally to overhang a deep groove formerly occupied by an ossicle that is still partially preserved on the L. Both mastoids arc thick and somewhat triangular in cross section, with a flat and extensive posterolateral s u r ^ c C that is also angled inward. On both sides the small but projecting tip of the mastoid process lies very latere y, with a relatively deep and wide mastoid notch lying anteriorly almost along the midline of the masto structure, with a thick and downwardly protruding paramastoid crest forming the medial part of the p truding mastoid region. The occipitomastoid sutu ^ lies at the medial base of this structure, where the oc cipital slightly overlaps the mastoid. On both sides elevated, ridgclikc and moderately long ^ ' P 1 * 0 1 ^ toid crests are seen only far posteriorly, entirely oc

IIADAR

the mastoid mass. Medial to these crests are long, deep and relatively wide depressions that are bounded mcdiallv by very long, low Waldeyer s crests. As seen especially on the L, anterior to the occipitomastoid crests, and somewhat separated from them, is a modera telv sized foramen into which a long groove descends. The relatively broad nuchal plane is quite long a/p, whereas the occipital plane is quite short s/i. If the lambdoid suture is correctly identified internally, it would have peaked broadly at lambda, which would have lain very low. The nuchal plane undercuts the rather vertical occipital plane, almost horizontally. The angle between the planes is marked by a sharp, irregular and downwardly distended ridge that corresponds to the superior nuchal line. This ridge is distinctly downwardly peaked in the region of the external occipital protuberance. As better seen on the L, the posterior part of the temporal line curves sharply laterally above this ridge. The two temporal lines apparently met in the midline above the low lambda, without forming a distinct crest. The nuchal plane seems to •have been devoid of significant muscle markings, except laterally in the form of the occipitomastoid and Waldeyer s crests. Internally, the impression of the L occipital pole is smaller and deeper than its R counterpart, whereas the opposite is the case for the cerebellar impressions, which face downward. On the L, the occipital and cerebellar impressions are separated by a blunt horizontal ridge that lacks a groove for a transverse sinus. This ridge emanates from a low, broad internal occipital protuberance, obliquely down which a groove runs that may have served for accessory drainage. As reconstructed on the R, a blunt ridge also emanates laterally from the internal occipital protuberance and runs between the occipital and cerebellar depressions. About 2.5 cm lateral to the internal occipital protuberance, a groove descends mcdioinferiorly from below the R lateral ridge. On both sides the posterior part of the petrosal is fairly deeply and broadly excavated on its medial surface. These large concavities correspond to the position of the sinuses but are not configured like them. A ne superior surfaces of the petrosals arc broad and »at, with no indication of a superior petrous sinus. On both sides the subarcuatc fossa is very inferiorly placed, and its region is hollowed out. The internal acoustic foramina arc very small, and it appears the Petrosals were fully ossified toward their ends.

69

Mandible. This is a damaged and reconstructed massive R corpus with a tiny bit to the L of the midline, but missing the posterior corpus and all of the ramus. All preserved teeth arc badly damaged and partially reconstructed. L I 2 - R M 3 arc present, in various conditions of completeness. A piece of crown glued to the broken root of the RC docs not seem to match, either in coloration or in state of wear. The corpus is very tall s/i, but only moderately thick m/1. Viewed from above, the tooth rows would probably have diverged quite strongly. The front of the jaw was evidendy moderately narrow, with a moderate arc across the front, and there arc no notable features on the external aspect of the symphysis apart from a very shallow depression close to the inferior margin around the level of R I 2 - C . In profile the symphyscal region is essentially vertical for much of the distance below the alveolar margin, only curving back near the inferior margin. The moderate mental foramen lies under the region between P I and P2, and the bone above the foramen is broadly but shallowly depressed. The anterior root of the ramus apparendy took origin just behind M2, and expanded out and away from the molar region, creating a moderately broad mandibular gutter. Internally there is a short, slightly concave and quite steeply sloping postincisal plane that extends only as far as the P I . At this point the bone is broken but it appears that the internal surface of the symphyseal region was more vertical farther inferior!v. No genial structures are preserved; what appears to be the R digastric fossa, expressed as a thin, posteriorly facing scar, lies quite far laterally below the region of R I 2 - C . The internal surface of the corpus is extensively damaged, but it docs appear that there was no internal alveolar crest of any note. Incisors are heavily worn, but quite high-crowned and narrow m/d, with moderate crown flare. The roots of the broken I2s are quite compressed m/d, like the l i s , but are larger. The broken C root is compressed and obliquely oriented; the crown was probably slender. There appears to be a modest diastema between the C and the P i . Both Ps appear to be three-rooted, with the m/b root being obliquely distended mesially, giving an oblique orientation to the crowns of both. Both P crowns are quite worn and damaged, but it appears that PI was shorter m/d than P2. Although broken, the molars would not have been very large, and they do not seem to have decreased much if at all in size from front to back. As seen on M l , the roots diverge right below the crown; also, M l probably bore

70

a centrally placed hypoconulid. M l and M 3 , at appear to have been a bit wider b/1 mesially distally. Lower molar wear seems to be greater that seen on the upper Ms (inconsistent with association).

SITE

least, than than their

AL 333-84. Part of a L petromastoid region. Very similar to AL 444-2 in having a large mastoid mass with p/1 flattened surface, and a low but distinct mastoid peak lateral to a centrally placed mastoid notch. The notch is bounded laterally by a low paramastoid crest. A large stylomastoid foramen lies at the anterior base of the mastoid mass, in line with the mastoid notch. Quite lateral and somewhat anterior to this foramen lies a small styloid pit at the posterior side of the long tubular ectotympanic. There is no vaginal process. Internally the posterior part of the petrosal is very broad, and its superior surface is essentially flat. There is no evidence of a superior petrous sinus. The subarcuate fossa is low and strongly indented, and the sigmoid sinus is narrow, deep, vertically oriented and almost straight. The sinus begins abruptly superiorly, and not as the continuation of a distinct transverse sinus. AL 333x-l Upper Dental Morph (includes A L 3 3 3 86,333-105,465-5) Although it might seem that the configuration of the virtually identical dm 2 s of the two juvenile specimens included here (333-86 and 333-105) is potentially reconcilable with an upper molar size-shape gradient seen in specimens assigned here to other morphs, the distinctive M 1 of 333-86 is not comparable to the M ] s of any of these specimens. Rather, it is better associated morphologically with 333x-l, an isolated upper M or M 3 , that is easily distinguished in its details from other upper Ms in the sample. AL 333-86. Broken L and R maxillae of a juvenile, with a glued piece impeding contact. As preserved on the R, the inferior nasal margin curves around to what would have been a midline keel. The nasal aperture was apparently narrow, and the floor of the nasal cavity flows smoothly on to the clivus. Posteriorly there was a steep step from the posterior pole to the floor of the cavity. In cross section the shallow palate thickens from front to back. On both sides there is a pronounced canine fossa, and an incipient "facial pillar" on the R. The anterior root of the zygomatic arch faces forward on both sides, and the infraorbital region is vertical and was probably flat. As seen on the

ENTRIES

L, the maxillary sinus is very large. A moderately 1 infraorbital foramen lies well below the r*^0 ri0r orbital margin. Dentally there are alveoli for R I l - C , dml are in place and there is an M l crown in'its cry "t each side. The dmls and, to some extent, both T m/d and b/1 much larger dm2, are worn. Both drr^ C three-rooted. The dmls have a small metacone a* prcssed to a larger and mesially swollen paracone. Th~ protocone is slightly centrally placed, and' the hypocone is relatively large and d/1 swollen. A distinct crest runs from the hypocone up to the apex of th metacone, lying higher than the cusps for most of its extent. A preprotocrista runs around the base of the paracone, and a short postprotocrista runs to the distal side of the base of the metacone. The dm2s are much larger and squarer than the dmls. The metacone and slightly smaller paracone are subequal and separated; the large protocones are centrally placed; the hypocones lie opposite the metacones, but also extend more distally; the cristae and postcingula are similar to d m l ; and there is also a short precingulum at the base of the protocone. There is some enamel wrinkling. T h e M i s are rather long m/d, with quite extensive but shallow wrinkling, a distinct talon basin and a very open trigon basin (because of the peripherally placed trigon cusps and the markedly mesially arcing preprotocrista, which curves in to join the apex of the paracone). The relatively large protocone is more crestlike than the buccal cusps are, and a thick postprotocrista courses b/d from it to the very internally terminating base of the metacone (the base of the paracone is similarly internal, with a conule just above the bottom of the trigon basin). The apices of the buccal cusps are far apart, and their facing sides bear cristae that ascend into the notched juncture of their bases. The hypocone region is shelflike and quite distally enlarged, and the thin, crcstlike postcingulum courses gently d/1 to merge into its also crestlike margin. There is a ver)' short prchypocone crista between the bases of the hypocone and protocone, but below the level of (not confluent with) the postprotocrista. AL 333-105. Crushed, deformed partial cranium of a juvenile, missing most of the L face and palate, the R parietal, part of the R frontal, the R temporal, the L parietal and all of the occipital. Retains onl) alveoli for R d i l - d c and the crowns of the very worn d m l - d m 2 ; the crown of M l is partially visible in it* crypt.

II A DA R

This was probably a relatively high-domed and rounded cranium; it is somewhat crushed from side to side. The face is relatively narrow, with a smoothly domed frontal rising somewhat vertically and directly from thin, unadorned supraorbital and essentially flat glabellar regions. In profile the face was probably smoothly but shallowly "dished" (concave) below nasion, with more marked anterior extension ot the prcmaxillary region. From the contour of the R superior orbital margin and the length of the thin R frontal process of the maxilla, the orbits were probably tall, ovoid and narrow, and separated by a narrow intcrorbital region. The position of the frontonasal suture is uncertain, but it appears that the thin pair of nasal bones tapered superiorly for some distance, even beyond the frontomaxillary suture. The R lacrimal fossa is partially preserved; it was tall, narrow and teardropshaped, with a discernibly distinct lacrimal crest only posteriorly, low down around the fossa. The lacrimomaxillary suture lies right on the margin of the orbit. The frontal process of the zygoma was tall and antcrolatcrally facing. The relatively large infraorbital foramen lies moderately below the inferior margin of the orbit, on the slightly concave and anteriorly facing plane ot the anterior root of the zygomatic arch that takes origin somewhat above the alveolar margin. As seen from the front, the inferior margin of the anterior root ot the zygoma slopes out steeply before turning laterally. The maxillary tuberosity is quite well developed, and the body of the zygoma, as seen from below, curves smoothly and broadly back around into the arch, which encloses a fairly large, anteriorly broad and distended temporal fossa. The posterior surface of the zygoma body is deeply excavated (ci\ 333-1). Very taint interior and superior temporal lines emerge from behind the unexpanded R frontal process of the zygomatic, and curve directly back. The bone lateral to the nasal aperture is essentially flat, although there is an indication of a slight canmc pillar below the nasal margin. As preserved laterally, the floor of the nasal cavity flows smoothly on to the external surface of the long, forwardly sloping nasoalveolar clivus. The clivus bears the impressions ot the di roots. In cross section the clivus appears to have been uniformly thick from top to bottom, with its posterior pole not overlapping the palate extensively. The palate itself may also have been uniformly thick throughout its length. The pterygoid plates are broadly divergent and lie right behind the Posterior pole; they were probably confluent interiorly.

71

The lateral was probably larger than the medial. The preserved inferolateral corner of the nasal aperture is strongly curved, and the aperture itself was probably neither very wide nor verv tall. There is no bulge or conchal crest visible within the nasal margin. From the side, the relatively thin preserved z}*gomatic arch rises gentlv, then descends to the thin posterior root that lies above and anterior to the ovoid, very anteriorly oriented auditor}' meatus. There is a fairly well-defined suprameatal crest that flows posteriorly into the superior bulge of the developing mastoid mass. Anterior to the auditor}' meatus is an anteriorly widening bony shelf on the top of the posterior root, under which lies part of the a/p long but shallow and m/1 very wide articular fossa. The fossa on the L is of similar shape. Both are closed off slightly on the medial side by a low tubercle, but arc unbounded anteriorly. Posteriorly, as seen on the better preserved R side, the fossa is bounded by the low, flat cctotympanic tube, which is not fully ossified laterally. The surfaces of the cctotympanics are essentially flat, except for a short, peaked ridge quite far forward along the petrosal. The relatively small carotid foramina point back, and lie in front of the jugular fossae; the latter on the R is small and points down. Also as seen on the R, the carotid foramen lies right across from the large anterior condylar canal, and lateral to the carotid foramen the petrosal and the tube are laterally oriented. Anterior to the foramen the petrosal curves anteriorly. As seen better on the L, and somewhat lateral to the carotid foramen, are two pits, one in front of the other. The anterior one is probablv the styloid pit, and the posterior the stylomastoid foramen. The mastoid mass itself is quite large for a juvenile, and posteriorly shows a distinctly flat, inwardly inclined and somewhat laterally facing plane. At its low inferiormost extent, in its midline, is a thin, incipient mastoid notch with a slight rise on either side. Internally, the frontal lobes projected well forward into the frontal bone, probably fully over the orbital cones. The impressions arc very deep, and taper strongly anteriorly. The anterior cranial fossa is capacious, and the antcriormost frontal depressions arc separated by a relatively thick and long frontal crest. The jugal and ethmoid regions arc missing, but as preserved on the L, there is a relatively short, vertical superior orbital fissure that swells somewhat at its inferiormost extremity. There is no inferior orbital hssure. Also as seen on the L, the foramen spinosum lies entirely within the temporal, and the foramen ovale

72

S i r K ENTRIES

lies at the base of the somewhat rbrwmllv facing lateral pterygoid plate, thus within the sphenoid. As seen on both sides* the baud groove for the middle meningeal artery bifurcates about 5 mm up from the foramen spinosum, sending one branch forward and another posteriorly. Both cross the squamosal, somewhat posteriorly within the large middle cranial fossa. As better preserved on the L, the petrosals are quite baud and smooth superiorly, lacking any evidence or a superior petrous sinus. The posterior part ot the vertical wall is deeply and broadly excavated. As better seen on the L, the subarcuate fossa is completely flattened over, and the area behind the petrosal is excavated. Below this excavation, on the R, is seen a small trace of sigmoid sinus. Part of the region around the foramen magnum is preserved on the L. It appears that the occipital condyle lay far forward but still entirely on the lateral part of the occipital. Internally, running parallel with the margin of the foramen, is a broad and shallow groove that goes directly to the jugular foramen, implying that cerebral drainage was not exclusively via the sigmoid sinus. Not unexpectedly for a juvenile, the palate is shallow throughout its length. The greater palatine foramen is huge; there is no information on the incisive foramen. The II alveolus is round, the 12 more ovoid. Both I roots were apparently short and of similar size, and somewhat forwardly inclined. The dc root would have been rounder and somewhat larger. The worn dml is somewhat roundcdiy square. The preserved protocone and paracone are equally large and compressed. There is evidence of a small metaconc appressed to the side of the paracone. All three cusps are incorporated into a cresting system that surrounds a moderate basin truncated by the somewhat centrally placed protocone. A distinct, moderate-sized, but distally swollen hypocone is separated from the smaller protocone by a deep wedge-shaped depression; a short but distinct prchypocone crista courses across this depression between the two cusps. A thick postcingulum runs from the hypocone to the distal side of the metacone. There is a large "Carabclli's pit," and the tooth has three roots. The much larger dm2 is squarer and more recognizably molariform, with a very large metacone and hypocone. The configuration of the trigon is similar to d m l , but the basin is shallower and the paracone is noticeably smaller than the metaconc. The enamel was somewhat wrinkled. Both dms bear a thick but short

prchvpoconc crista that emanates from the tticst 1 side of the hypocone and courses dircctlv mesiallv t the base of the protocone, terminating below the Icvrl of the postprotocrbta (which bears a conule on dm2) Only the trigon of M l can be seen in the bone; the enamel is wrinkled, and the trigon basin is large with the cusps well separated and at the perimeter of the tooth. The teeth in this specimen are similar to those in the juvenile palate 333-86, except that the teeth in the latter arc a bit larger. AL 465-5. Fragment of upper LM. Cf 333x-l. /\L 333x~L RM J or M \ probably not fully erupted. Two buccal roots diverge close to the crown, which is m/d elongate and fairly wide across the mesial cusps. It tapers roundcdiy distally due to the backward arc of the thick, beaded postcingulum, which terminates on the distal side of the hypocone. The lingual side slopes strongly, the buccal side only minimally. The paracone and protocone arc especially compressed cusps and incorporated into a cresting system that rings the trigon basin. Because the very m/d wide protocone is somewhat internally placed, the basin is narrowed b/1, but it extends mcsially a little because the prcprotocrista runs as a shelf from the massive protocone, mcsially around to the apex of the peripherally placed paracolic. The short postprotocrista runs buccally, and slightly distally, to the base of the small, m/d truncated and peripherally placed metaconc, from the distal side of which the thick, short postcingulum emerges. A stout but short prchypocone crista courses directly mcsially from the apex of the hypocone to the apex of the protocone, connecting with the prcprotocrista. I here is a moderate V-shaped notch above it, between the two cusps. The internal enamel is moderately crcnulatcu, and the entire lingual side of the protocone bears cingulum, as well as vertical ridges o( enamel and a very mcsially placed protostylar pit. Unassignable to Morpli (including uninfonnativc and possibly nonhominid specimens) Maxillae, Upper Teeth, and Cranial Fragments AL 161-40. Small L M \ somewhat weathered and with four broken roots divergent from neck. Alxnit a* wide b/1 across the large mesial cusps as it is long m i • Tapers to a tightly rounded distal side. ' postcingulum emerges from the side of the tiny a »l truncated metaconc, and swells into the distally p l ^ °

HAOAK

hvpoeone. Probably its surface was originally thickly crcnulatcA. AL 19^-17a. LI 1 . Worn, root broken, distal edge more flared; traces of mesial and distal vertical foveac on lingual surface* AL 198-I7h Weathered probable Rdi>. Flared disrally. AL 293-3. RI l , broken, stout not long root, broad, laterally flaring crown. AL 333-L Matching hemimaxillae with anterior zygomatic regions attached and nasal region missing except right at the front. RP1-P2 and broken M1-M2; LP1 and broken C and P2. All heavily worn. Also alveoli for RC-LI2. Crushed, distorted and partly reconstructed. This was a relatively small individual that appears to have had a relatively narrow snout and inferior nasal aperture. The nasoalveolar clivus, as better preserved on the L, is relatively short. Its upper surface is strongly arced from front to back, and its anterior and posterior poles are tapered. As seen on both sides, the posterior pole does not extensively overlap the very thin preserved palate, from which it is separated by a moderately sized canal. What can be construed as anterior nasal spines lie well within the nasal cavity, at the posterior pole of the clivus. On both sides, just behind the apex of the II alveolus and just within the nasal cavity, lies a m/1 broad, a/p moderately long and fairly well-excavated fossa that runs partway up the lateral wall of the nasal cavity. Thus the floor of the cavity did not flow smoothly on to the external surface of the clivus. Laterally, the floor of the nasal cavity descends smoothly down and back, whereas there is a marked step from the posterior pole to the floor. It is impossible to tell if the incisive fossa was subdivided. The clivus was probably broadly curved from side to side, its external surface showing the bulges of the tooth roots. As seen on the R, the massive canine root extended well above the inferior margin of the nasal, and as best seen on the L, this canine root pillar flows into the rounded bone lateral to the nasal aperture and slants medially as it rises. Behind the canine/facial pillar, on both sides, is a deep, rather tall, and laterally facing fossa that is confined above the buccal roots of P1-P2. As seen on both sides, the anterior origin of the zygomatic arch lies above M l , and as preserved on the R, it is high up. Viewed from the front the inferior margin of the root curves strongly laterally; the infra-

73

orbital region on both sides is tall and forwardly facing, and was probably flat. As seen from the R side, the inferior margin of the zygomatic arch runs strongly up and back. Laterally, us seen better on the R side, the body of the zygoma curves strongly posteriorly. Its extensive surface for masseteric attachment faces outward and up. The small midportion of the zygomatic arch tilts slightly outward; the bone is thin m/l and moderately tall s/i. The orbits apparently sat very high up on the face. Internally, as better seen on the R, the maxillary sinus extended laterally into the thin anterior root of the zygomatic arch, and as seen on both sides it extended up into the bone on either side of the nasal aperture. In the region preserved the palate is quite narrow and very shallow, being almost flat across from side to side. The cheek tooth rows probably did not diverge significantly. The bone of the incisive foramen is partially broken, but two moderately long, shallow, parallel grooves emerge from the foramen on to the palate. The II alveoli are larger and more rounded than the 12 alveoli. The damaged LC is quite thick b/1 at its base, although it is not very broad m/d. It probably was a slender but tall-crowned tooth. It preserves a trace of a mesial margocrista high up, and a distal marffocrista alone its base. The RPs are very worn, but PI is more symmetrical and P2 more swollen d/1 and more tighdy curved buccally. In both teeth the protocone is mesially shifted; in PI the paracone is central and on P2 it is more mesial, but on both Ps there is a distinct "metastylar" region that is probably the terminus of a thick postcingulum that roundedly "squares off" the d/1 corner. The molars are excessively broken, but a shallow buccal notch on the apparently m/d short and b/1 wide M l indicates that the paracone was larger than the metacone. In what is preserved, the Ps and Ms of 333-1 arc much larger than in 333-2 (below). In 333-1 there is a large C fossa and root pillar; in 333-2 these arc absent. The Cs are also different, being much more parallelsided and triangular in outline in 333-1 than in 333-2. AL 333-2. Crushed and distorted anterior maxilla with LI2-P2, RI2-M1 and a fragment of RM2. R12 and M l are also broken, other crowns extremely worn; also alveoli for both lis. This specimen is compressed laterally, but probably was narrow-snouted with a narrow nasal aperture. Nasal fossa is too damaged to describe, but the clivus

74

SITE

curves quite strongly and smoothly down. C roots are long and more or less vertical, creating slight bilateral bulges. T h e broken anterior root ot the zygomatic arch lies moderately above M l . and there appears to be no fossa between it and the premolars. T h e palate appears to have been shallow to the level or" the P2, behind which it probably deepened somewhat. T h e II alveoli housed long, stout-rooted teeth. T h e 12 roots are very slender and short. As seen on the L, the lingual surface of 12 bore continuous margocristac around its base. There probably was no diastema. T h e Cs were probably very tall-crowned and relatively stout, and their long distal and shorter mesial slopes are straight; their relatively unexcavated lingual surfaces bear modest margocristae. P 1 - P 2 are generally similar in shape, but P2 is a bit longer ni/d. M l is too broken for much comment, but it appears that the paracone had been much larger than the mctacone. In this regard, and in the size and shape ot the C, 333-2 is generally reminiscent ot 444-2. AL 331*23. Thin piece of cranial vault bone, possibly parietal. Broadly curved. AL 333-45. Partial posterior cranial vault in two pieces, the larger on the L, containing part of the temporal with the mastoid region, a large part of the L and a small part of the R parietal attached, and much of occipital to just R of the midline. T h e r e is a small contact between the two sides just in front of the superior nuchal line. T h e R piece has the petromastoid region and part of the occipital. T h e r e is some cracking, reconstruction and weathering. This was a smallish individual, and moderately thick-boned tor its size. In protile the posterior vault is moderately low, with a good continuous curve down to lambda, below which the occipital protile becomes almost vertical. A t the slightly posteriorly projecting superior nuchal line the relatively short nuchal plane angles strongly forward and down. Seen from behind this was a very wide skull, and widest across the posterior root ot the zygomatic arch, which lies just in tront ot and level with the superior margin of the auditory meatus. Lateral to the posterior root of the zygomatic arch the cranial outline is strongly outwardly sloping trom the gently inwardly curving vault wall. As seen on the L, the squamosal suture would have been long and low, with a long, shallow superior arc that would have continued well over the mastoid region posteriorly. T h e parietal portions of the temporal lines are visible at around the midpoint ot the

ENTRIES

cranium, where they form a broad, flattened K, slightly raised and bandlikc surface. The po below and medial to the parietal notch extension, on b runs se ndv upward before turning horizontally to

75

11 A n A U

across the midline. The midline urea appears to be thickened, but is somewhat damaged. The occipital plane is thus technically very wide, but has only a limited planar surface. By comparison, the nuchal plane is unifbrmlv broad from side to side. Just lateral to the occipitomastoid suture, and extending anteriorly from the level of the tip of the mastoid process, there was a low, broad paramastoid crest. Medial to the paramastoid crest is a long broad, shallow depression that broadens posteriorly and is bounded at least on its anterior half by a Waldcycr's crest that is distinct on the L and less so on the R. This depression is deepest posteriorly, where it almost meets the thickened and distended superior nuchal line. Between these depressions, the nuchal plane was apparently quite featureless. As apparently partially indicated on the L, a bit of the foramen magnum is preserved. The foramen was apparently very wide, and its anterior margin extended at least as far as the level of the posterior part of the articular fossa. As seen on the R, the occipital condyle is relatively long and strongly curved downward, reaching its lowest point quite far posteriorly, over the postcondylar fossa. Its articular surface is flat, and obliquely oriented up and laterally. Internally, as preserved on the R, the petrosal is very massive. It has a very broad and flat superior surface and a rather deep vertical surface. There is a shallow superior petrous sinus just on the superior surface posteriorly. The superior and vertical surfaces of the petrosal form a sharp corner. The subarcuate fossa is totally closed over, and the internal acoustic meatus is very small. A very deep and moderately wide and vertical sigmoid sinus runs posterior to the petrosal, and flows into the fairly narrow and forwardly pointing jugular foramen. The petrosal is depressed in the region just above the sigmoid sinus. O n the R, low down, is a moderately marked transverse sinus that is separated from the sigmoid sinus by a raised area of bone. Both transverse sinuses extend laterally from the very broad and low internal occipital protuberance at approximately the same level. The transverse sinuses lie well below the level of the superior nuchal line, and it appears that the internal occipital protuberance lies below the level of the external thickening in the midline. The superior sagittal sinus is partly preserved, and is very deep. AL 333-82. Partial I 1 unerupted crown fragment. Buccal and lingual sides arc greatly divergent; the lingual side is quite excavated.

AL 333-99. Ldc 1 . Similar to 333-104. AL 366-1. LM> Broad and hi lid mesial root, more conical distal root, crown moderately worn. Kntoconid is the smallest of the four major cusps, and the hypoconulid region is cuspidated and expands the distal end of the tooth. It lias a section lying somewhat buccally, but not as far buccally as the hypoconid, which has a deep groove on either side. AL 388-1. L M \ highly weathered. Crown was m/d short, crown, with curved distal side. Paracolic and protoconc are somewhat distally placed, incorporated in a cresting system. Enamel is crcnulatcd. AL 438-Ik Frontal fragment including glabellar region. Probably not hominid: no frontal sinus; very flat above orbits, where there is a hugely expansive thickness of trabecular bone; and the preserved front of the braincasc is very tiny and would have contained a very small brain. AL 442-1. R partial maxilla with floor of nasal cavity and lower part of maxillary sinus, somewhat weathered and broken, more or less to midline. Alveoli for 11-2, roots for C - M l , worn and broken M 2 - M 3 . Very small individual. Smoothly curving infcrolatcral corner of nasal aperture, with smooth transition laterally from floor of nasal cavity on to the gently sloping, moderately elongate external surface of clivals. Laterally there is a gentle slope posteriorly along the floor of the nasal cavity. At the midline the posterior pole of the clivus curves down strongly toward the floor, being separated by a large incisive fossa containing part of the midline septum. The posterior pole only minimally overrides the palate, from which it is separated by a downwardly broadening canal (which seems pathologically enlarged). It would have opened into a relatively large incisive foramen, and is continued forward by grooves. In cross section the palate is pointed anteriorly, thickens at a point just behind the incisive fossa, then tapers gradually posteriorly. The nasoalvcolar clivus bore the swellings of the tooth roots, and is delineated laterally by a broad, rounded "canine pillar" that incorporates the region of the P I , above and behind which is a deeply excavated but somewhat restricted fossa. Behind this, and somewhat above the level of M l , it appears that the anterior root of the zygomatic arch is beginning to swell out lateral!)'. I l i c maxillary

76

SITE

sinus bears a. small anterior and posterior pocket* separated from t i e main sinus by a sepcuin. The palate is verv shallow- behind the Is, and gradually deepens posteriorh; the deepest point being at the large greater palatine foramen, which lies below M 3 , Posteriorly; the side wall of the palate is vertical. The root of the II probably arced forward and then down. The smaller 12 apparently arced more stronsjv down. Both had relatively short roots. The C root b neither stout nor long, but appears to be compressed, as also was the smallish crown. P I and P2 have two roots opposite each other. The teeth were wider b/1 than m/d long, perhaps almost as wide as the M l . The Ms were relatively small for the Jaw; Ml—M2 mav have been subequal and ^ D much short era; PAL 444-Ia. Portion of R occipital, with bit of Iarnbdoid suture that is broadly but not deeply denticulate. Bone is thickest at the swollen nuchal line. Internally, there is a portion of an a/p long transverse sinus. Nuchal plane would have been quite sloping. AL 444-1h. Uninformative occipital fragment. AL 457-2. Parietal fragment, relatively thickboned, with a broadly but not deeply denticulate part of the sagittal suture. A rise along the suture indicates a contribution to a sagittal elevation. Part of the coronal suture is also preserved: finely denticulate. Part of the squamosal suture is present. Apparently from an extremely low-vaulted skulL AL 333w-28. Worn RI 2 , root broken. Mesial edsre is more distended than the straighter distal edee. AL 333w-42. Worn RP 2 . Has somewhat mesially placed paracone and protocone, and a thick postcingulum that slightly swells out the tooth distally. There is a deep distal cleft on the roots, somewhat below the neck. AL 333x-2. LI 2 , with a very long root, stout but m/d compressed and mesially curved. Tall but narrow crown with slight distal flare, and a shallowly excavated lingual surface that is bounded by cristae confluent around the low basal tubercle. AL 333x-3. R upper C with a very stout and long root that is subovoid in cross section and bears a longitudinal mesial groove. Crown appears twisted relative to root. In side view the root curves down into the relatively short but stout crown that has a

ENTRIES

relatively short but steep mesial edge. Its longer but also steep distal edge terminates in a small swelling that corresponds to the terminus of a short distal margocristid. Also lingually there is a longer and more pronounced mesial margocristid and a short but low central pillar that curves just mesial to the midline of the teeth. There are deep vertical grooves just inside the margocristids. It is flatter on its lingual surface and strongly curved on its buccal surface. AL 333x-4. L l \ very worn and weathered. Stout but not very long root, more flare preserved distallv than mesially, AL 333.X-20. R l \ better preserved than 333.X-4, but similar to it. AL 400-lb. R upper C, small (female?) compared to 333x-3, to which it is similar except that it has a larger basal tubercle that also bears a pit. Mandibles arid Lower Teeth AL 166-S. L lower temporal region; not hominid. AL I9S-18. Worn RIj. Relatively long, m/1 wide root, crown apparently not very flared. AL 241-14. L (probable) M 2 , with two roots. B/1 narrow, roundedly rectangular, moderately worn. Strong buccal slope, lingual cusps more vertically bulbous. The somewhat b/1 compressed metaconid is minimally longer m/d than the protoconid. These two cusps are markedly larger than the others, and there is evidence of a paracristid coursing down along one cusp and then up the other, probably enclosing a very m/d narrow, creaselike trigonid basin. The squared-oft base of the m/d somewhat compressed hypocomd barely crosses the midline of the crown, making an m/d lone contact with the slightlv b/1 compressed entoconid and just touching the base or tne metaconid. The more strongly m/d compressed hypoconulid is quite buccally placed; it is lingually and a bit mesially oriented, such that its base makes tull contact with the rather bulbous entoconid. A tain} m/d large, "twinned* cusp lies up against the distal sides of the hypoconulid and entoconid; one "cuspulid" lies essentially at the midline of the tooth, the other (slightly larger) "twin" lingual to it. There are moderately deep vertical grooves on either side o the hypoconid. The narrow talonid basin is shitted

lingually.

HADAR

AL 311-1- L partial mandibular corpus missing inferior region. Cracked and weathered. I 1 - M 3 mostly broken, represented by roots except for P i , partiallv preserved. This is a chunk}* corpus with a deep, relatively short tooth row, and it is also fairly wide m/L Internal symphyseal curve had been tight, the outer slightly more rounded. Although cracked, the region below the incisor and canine roots shows no evidence of morphology. Apparently the symphyseal profile was smoothly out and then down and back to the inferior margin. The moderately large mental foramen lies far below P 2 - M 1 , and may have sat in a shallow depression. The anterior root of the ramus appears to have begun to swell laterally well below the region of M l . Internally, the moderately long postincisal plane is gently sloping to the region of P2-M1 where it curves gently down, probably to a fossa or pit not too far above the inferior margin. The mylohyoid line and crest on the internal alveolar margin are absent. The I roots are compressed m/d, the 12 larger than the I I . The C root is relatively large and ovoid in cross section, and obliquely oriented. PI had a T-shapc cresting pattern, with a small m/1-facing anterior fovea and a larger posterior fovea. The m/b root is slightly distended, as it is on the damaged P2. M1-M2 had been subsquare or rectangular; M 3 more elongate and rounded distally. AL 333-74. Fragment of L corpus containing very worn M 1 - M 3 . Bone is moderately thick m/L M1-M2 are not elongate; M 3 is, and tapers distally. AL 333-76. Ldi 2 .Tiny. AL 333-108. L mandibular ramus, greatly crushed. fall, wide ramus with a/p long and blunt coronoid process at same level as condyle. The sigmoid notch crest runs laterally to condyle; the gonial angle would have been fairly smoothly rounded, and lacking in muscle markings externally. AL 437-1. Incomplete L mandibular corpus with part of R at symphysis and preserving LM1-3 in various states of wear and damage. Alveoli for RI2-LP2. Fairly massive jaw. Tall s/i but not very thick m/L ihc check tooth rows were moderately divergent posteriorly, the internal and external curves at the front of the jaw being more or less parallel. Between the canines the alveolar bone bears shallow depressions corresponding to the spaces between the anterior tooth roots. Below these the symphysis is smooth, curving

it

strongly from side to side. In profile the symphysis is very* slightly indented in the region of the anterior tooth roots, below which it curves gently out and then down and back to the inferior margin. The inferior margin anterior to P2 is elevated, and probably also was posteriorly (thus a "rocker"). The moderately sized mental foramen lies well below P2; the anterior root of the ramus takes origin below M2. There is a mandibular gutter that may have been broad. Internally, the postincisal plane is quite long, somewhat concave, and very steeply sloping. It terminated in a fairly large pit halfway down the symphysis, from which a long, raised ridge of bone runs infcriorly to a point above the inferior margin of the jaw. What appears to be a digastric fossa runs from the midline to below the mental foramen. It is shallow, and faces posteriorly. No trace of a mylohyoid line or a submandibular fossa. No development of an internal alveolar crest. Judging from the alveoli, the 12 roots were much more compressed than the 11 roots. All I roots were wide b/L The somewhat stout C root was relatively long s/i, partially compressed m/d and obliquely oriented in the jaw. P 1 - P 2 were apparently not notably large; PI is apparently three-rooted. The m/b root in both is slightly mcsially displaced, giving an oblique axis to the tooth. The roots of M 1 - M 3 diverge close to the crowns; M 3 was probably the largest of the molars, and distinguished by a more expanded distal end. Its large hypoconulid was quite buccally emplaccd. AL 437-2. Mandible, with two isolated teeth: 4372a is identified as a lower RM3, but is actually from the L side, and probably an M2. 437-2b is identified as a lower RP1, but cannot go with the jaw since that tooth is already represented by roots (probably not hominid: suid?). The 437-2 mandible is a damaged and partially reconstructed corpus complete from LC to RM2; also broken and glued partial crowns of LC-RJ2, roots of R C - P 2 , very damaged crowns of M l - M 2 and mesial wall of alveolar region of M3. The Is may not be appropriately associated. This is a quite chunk)' mandible, but not a very large one. It is relatively wide m/1 but not very tall s/i. The bone thickens b/1 at inferior margin. The tooth rows would not have been very divergent; internal and external curvatures across the symphysis arc tight, and more or less parallel. Externally, between the Cs, the bone is indented between the tooth roots, with, below these indentations, a smooth lateral curve across. In profile the symphyseal

78

S I T K K N* T K I K S

region was probably vertical until near the inferior margin, where it curved gently down and back. This, too, would have been a rocker jaw; the front of the inferior margin was probably elevated anterior to P2, as is the margin behind. The region below the Is and just above the interior margin appears to have been indented externally. The partially preserved mental foramen lies halfway down the jaw below P2, and was moderately large. The anterior root of the ramus begins to rise gently from below the distal part of M l and flares outward quite strongly, creating what would have been a very broad mandibular gutter. The anterior margin of the ramus appears to have angled back quite strongly. Internally the moderately long postincisal plane is slightly concave and quite steep. It terminates in a deep fossa with two pits in it; below this, the bone swells out slightly, then curves back and down to the inferior margin. There is no digastric fossa or mylohyoid line, and only a very small, shallow submandibular fossa below the level of P2. T h e internal alveolar crest appears not to have expanded medially. T h e teeth glued into the positions of the R I 1 - R I 2 and LI1 seem to be associated with each other, but not with the jaw. T h e tooth glued into the position of LI2 is also problematic. T h e C roots are very stout, and these teeth are only slightly obliquely set in the jaw. As seen on the L, the partially preserved crown may have been relatively tall, but was not expansive laterally. P 1 - P 2 have three roots; the m/d root is slightly expanded m/b and the lingual root is somewhat expanded d/1, giving a slight obliqueness to each tooth crown. P I was shorter m/d than P2. T h e roots of M l diverge just below the crown. M 2 was probably larger in all dimensions than M l (suggesting 288-1 morph). T h e allegedly associated isolated M 3 is a lower L M , probably M 2 . Crown is partially broken and very worn. It does preserve part of a very extensive distal wear facet. It had a large crown that was probably not expanded distally, and shows extensive coalescence of quite massive roots. AL 438-1 }>. R mandibular corpus and partial ramus to just L of symphysis. All teeth broken. Roots preserved are R 1 2 - M 3 ; alveolus for RI1. Fairly massive; the corpus is not very tall s/i, but is quite thick m/1, especially around the region of M 2 . T h e tooth rows were moderately divergent posteriorly; the curve around the front of the mandible is tighter internally than externally. In profile the symphysis

bulges slightly out from the alveolar region, the back to the inferior margin. Seen from above t h ^ ^ physcal region is smoothly curved across, and th ^ served portion is featureless except for a shallow ° ***" crately long depression near the inferior m a m n ' ? ' the RC [cf. 444-2]. The inferior margin is ^ elevated in the front, and rises again behind P2 th "rocking" under the region of P2. The relatively \T but partly broken mental foramen lies below P2 T}f anterior root of the ramus takes origin just behind Mi* and expands rapidly laterally, creating a fairly j L ' mandibular gutter. In profile, the anterior margin of the very tall but probably not very long a/p ramus angles back strongly. The preserved external surface of the gonial region lacks muscle markings. The partly preserved sigmoid notch is tightly curved, its deepest point lying slightly posterior to its midpoint. Internally the postincisal plane slopes gentry to the region of P i , where there is a large and probably deep fossa in the midline. Below this there are two vertical shallow (genial?) pits, of moderate size, quite high above the inferior margin. Below the pits the bone curves down and forward. The symphysis thus had an ovoid cross section. O n the preserved R there is no indication of a digastric fossa. There is no mylohyoid line and only a very anterior and quite small submandibular fossa. There is no development of an internal alveolar crest, although on the preserved portion of the ramus there is a stout pillar that ran down from the region of the missing partially missing coronoid process. T h e partially preserved mandibular foramen lies well above the level of the molars, and appears to have been directed up and back. T h e bone around and lateral to the RI1 alveolus appears to have been remodeled. Less drastic pathology is evident in the alveolar bone around all the other remaining tooth roots. The RI2 is very narrow m/d and wide b/1. The rather stout C root is compressed m/d, and is oriented obliquely in the jaw. On PI and P2, which arc three- or possibly four-rooted, the m/b root is distended forward, and the d/1 root h ^ T l giving a long oblique axis to the crown. PI h*1 slightly narrower m/d crown than P2. M l appears have been longer m/d than M2, and M3 longer than either. The distal side of M I - M 2 was more or les straight, but expanded somewhat d/1 on M3. AL 77§-hh Maxillarv fragment, with very worn part of P 2 - M 3 . 770-lb is a maxilla with v e r y ^ P 2 - M 3 ; both are very weathered and some tcetn .

II A D A R

broken. R C root is very tiny. T h e M increased in size from M l to M 2 ; M 3 may have been wider b/1 than either. T h e M 3 s have rounded distal edges (cf. orangutan clade). AL 333\v-16. L mandibular condyle. Coronally convex with downward flexion on medial aspect. Very laterally terminating sigmoid notch crest. AL 333\\-27. Weathered fragment of L mandibular corpus with very worn and cracked M 3 , which is massive, almost square with rounded corners and distal end. By comparison with this tooth, the corpus is rather narrow m/1. Uninformative A L 249-26, 249-27, 321-112, 333-44, 333-53, 333-77,333-103,333-114,333-116,333-24,333w-12, 333x-17. Probably not Hominid AL* 58-22, 162-28, 3 3 3 - 3 5 , 3 3 3 - 6 7 , 3 3 3 - 7 7 , 333-125,438-2b, 333\\-S2.

REFERENCES Falk, D. and G. C. Conrov. 1983. The cranial venous sinus system in Australopithecus afarensis. Nature 306: 7 7 9 - 7 8 1 . Holloway, R. L. 2000. Brain. In: E. Delson et al. (eds.), Encyclopedia of Human Evolution and' Prehistoryt2nd cd. New York: Garland Press, pp. 141 - 1 4 9 . Johanson, D. C. and Y. Coppens. 1976. A preliminary anatomical diagnosis of the first Plio/Pleistocene hominid discoveries in the central Afar, Ethiopia. Am. J. Phys. Anthropol. 45:217-234. Johanson, D. C. and M . Edcy. 1981. Lucy: The Beginnings of Humankind. New York: Simon and Schuster. Johanson, D. C. and T. White. 1979. A systematic assessment of early African hominids. Science 202:321-330. Johanson, D. C , T. White and Y. Coppens. 1978. A new species of the genus Australopithecus (Primates, Hominidae) from the Pliocene of eastern Africa. Kirtlandia 2 8 : 1 - 1 4 . Johanson, D. C , M . Taieb and Y. Coppens. 1982. Pliocene hominids from the Hadar Formation, Ethiopia (1973-1977): stratigraphic, chronologic and palcoenvironmental contexts, with notes on hominid morphology and systcmatics./*///./. Phys. Anthropol. 5 7 : 3 7 3 - 4 0 2 . Johanson, D. C. et al. 1976. Functional implications of the Afar knee joint. Am. J. Phys. Anthropol. 44:188. Johanson, D. C. ct al. 1980. New discoveries of Pliocene hominids and artifacts in Hadar: International Afar

79

Research Expedition to Ethiopia (fourth and fifth field seasons, 1975-77)./ Hum. EvoL 9: 5S3-5S5. Kimbcl, \V, H. and T. D. White. 1988. A revised reconstruction of the adult skull of Australopithecus afarensis. J. Hum. Evol. 17: 545-550. Kimbcl, W. H., D. C. Johanson and Y. Rak. 1994. The first skull and other new discoveries of Australopithecus afarensis at Hadar, Ethiopia. Nature 368: 449-451. Kimbcl, W , Y. Rak and D. C. Johanson. 2004. The Skull of Australopithecus afarensis. New York: Oxford University Press, 254 pp. Kimbcl, W. H., T. D. White and D. C. Johan son. 1984. Cranial morphology of Australopithecus afaremir. a comparative study based on a composite reconstruction of an adult skull. Am. J. Phys. Anthropol. 64: 337-3S8. Leakey, M. G. ct al. 2001. New hominin genus from Eastern Africa shows diverse middle Pliocene lineages. Nature 410:433-440. Lovcjoy, C. O. 19S8. Evolution of human walking. Sc. Am. 259: U S - 1 2 5 . Olson, T. W. 1981. Basicranial morphology of the extant hominoids and Pliocene hominids: the new material from the Hadar Formation, Ethiopia, and its significance in early human evolution and taxonomy. In: C. B. Stringer (cd.), Aspects of Human Evolution. London: Taylor and Francis, pp. 99-128. Susman, R. L. and J.T. Stem. 1991. Locomotor behavior of early hominids: cpistemology and fossil evidence. In: B. Senut and Y. Coppens (eds), Origines de la Bipe'die Chez les Hominides. Paris: CNRS, pp. 121-131. Taieb, M. ct al. 1974. Decouvertc d'Hominidcs dans les series plio-pleistocenes d'Hadar (Bassin dc l'Awash; Afar, Ethiopic). C. R. Acad. Set. Paris, D, 279: 735-73S. Taieb, M . et al. 1975. Expedition internationale de TAfar, Ethiopie (3c campagne 1974); decouvertc d'Hominides plio-pleistocenes a Hadar. C. R. Acad. Sci. Parisy A 281: 1297-1300. Taieb, M. et al. 1976. Geological and palacontological background of Hadar hominid site, Afar, Ethiopia. Nature 260:2S9-297. Tobias, P. V. 19S0. ""Australopithecus afarensis" and A. africanus: critique and alternative hypothesis. Palaeontol. Afr. 23:1-17. Walter, R. C. 1993. Age of Lucy and the First Family: single-crystal Ar/Ar dating of the Dcncn Dora and lower Kada Hadar members of the Hadar Formation, Ethiopia. Geology 22: 6 - 1 0 . Walter, R. C. and J. L. Aronson. 1982. Revisions of K/Ar ages for the Hadar hominid site, Ethiopia. Nature 296:122-127. Walter R C and J. L. Aronson. 1993. Age and source of the Sidi Hakoma Tuff, Hadar Formation, Ethiopia. / . Hum. Evol. 25:229-240.

80

SITE

ENTRIES

White, X, D. C. Johanson and W. H. KimbcL 1981. Australopithecus africanus: its phyictic position reconsidered. S.A/.J. Sci. Th 445-470,

HADAR

Repository National Museum of Ethiopia, PO Box 79, Addis Ababa Ethiopia.

Figure 1. NMEAL128-23,R mandibular corpw(scale**lem).

HADAR

HADAR

HADAR

Figure 2. NME AL145-25, partial L mandibular corpus (scale - 1 cm).

feure 3. NME AL 188-1, partial R mandibular corpus (scales - 1 cm). Figure

81

S I T E ENTRIES

82

HADAR

Figure 4. NME AL 198-1, L mandibular corpus (scales =» 1 cm).

HADAR

TADAR

83

Figure 5. NME AL 199-1, R maxilla, including views from above and behind (scales = 1 cm).

SITE

84

HADAR

HADAR

ENTRIES

Figure 5.

(Continued).

Figure 6. N M E AL 200-la, R and L partial maxillae (scales = 1 cm).

HADAR

HADAR

Figure 6. (Continued).

85

>.

86

SITE

Figure 7. N M E AL 207-13, partial mandible (scale = 1 cm).

HADAR

ENTRIES

H A D A R Figure 8. Top L: N M E AL 241-1, lower LM; Top R: N M E AL 353w-48, lower LM; Middle L: N M E AL 200-lb, lower RM; Middle R: NME AL 366-1, lower RM; Bottom: N M E AL 333-30, lower Rdm2 (scale = 1 cm).

51A DA R.

HADAR

Figure 9. NME AL 266-1, partial mandible (scales = 1 cm).

87

SlTfc E N T K I E *

88

HADAR

Figure 10. NME AL 277-1 , partial L mandibular corpus (scales = 1 cm).

HADAR

HADAR

89

Figure 11. NME AL 288-1; mandible is 288-li-k, frontal fragment is 288-lh (seales - 1 cm).

S I T B ENTRIES

90

HADAR

Figure 11. (Continued).

HADAR

HADAR

Figure 12. NME AL 330-5, partial mandible (scales - 1 cm).

91

SITE

92

1

'

'

'

'

"

:

-

ENTRIES

"

•

• '

•

'

'

'

•

:

'

:

•

11

'• ' " . B H M |

ill

li?i«il §ttfci|M |H

^K

^^nfgg^Bj^f^H

•ill •

•

•

HgHH

HADAR

Figure 13. NME AL 333-1, R and L facial and palatal fragments (scales = 1 cm).

HADAR

HADAR

Figure 14. NME AL 333-2, partial maxilla (scales 1 1 cm).

93

i

S I T E EXTMIB*

94

HADAR

Figure 15. NME AL 333-43a and b, partial R and L juvenile mandibular corpora (seal

HADAR

HAOAH

Figure 16, NME AL 333-45, partial rear of cranium (fcak* « 1 cm).

95

SITE

96

HADAR

HADAR

ENTRIES

Figure 16. {Continued).

Figure 17. NME AL 333-84, partial L mastoid region (scales « 1 cm).

97

HADAR

E$ lit* ;

|

#

BS^CR/ 1

H

HADAR

^

1 ,»^ghw

• ^W^JL^^^S^;

^1

Figure 18. NME AL 333-86, partial R and L maxillae (scales = 1 cm).

.

L^rsS 1

98

SITE

HADAR

ENTRIES

Figure 18.

{Continued).

Figure 19. Canine teeth, from L to R on each plate (L plate is lingual view, R plate is buccal): NME AL 333-104,199,77,35 (scales 1 1 cm).

HADAR

HADAR

HADAR

Figure 20. NME AL 333-105, partial juvenile cranium (scales = 1 cm; close-ups unsealed).

99

SITE

100

HADAR

ENTRIES

Figure 20.

{Continued).

HADAR

HADAR

101

Figure 21. L: N M E AL 333w-la, L partial mandible; R: AL 333w-lb, R partial mandible (scales 1 1 cm).

HADAR

Figure 22. L: N M E AL 333w-lc; R: 333w-le, mandibular condyles (scale = 1 cm).

SITE ENTRIES

102

.

•

1

E9|

PNQj

El

- •1

^^1

HADA»

L

Figure 23- NME AL 333*40, partial mandible (oafo ** 1
HADAR

Figure 24. NME AL 333x-l, upper RM (scale « 1 cm).

HADAR

103

Figure 25. From L to R: NME AL 333x-20, 4,2, upper incisors (scale s 1 cm). HADAR

SITE ENTRIES

104

Figure 26. L: NME AL 388-1, upper LM; Center: AL 161-40, upper LM; R: AL 333w-42, upper RP2 (scale = 1 cm). HADAR

HADAR

Figure 27. NME AL 400-la, R and L partial mandibular corpora (scales m 1 cm).

HADAH

105

p v ^^^B

K? %m, ff-

HADAR

Figure 27. {Continued).

&

jH

i

106

HADAR

S I T S EXTKBSS

Figure 28. Buccal (L) and lingual views of upper canine teeth. L: NME AL 400-lb; R: 333x-3 (scales - 1 cm).

HADAR

HADAR

107

Figure 29, NME AL 417-ld, partial lower face, and 417-Ic, partial sphenoid region (scales = 1 cm).

108

SITB EHTEIB*

HADAR

Figure 29.

(Continued).

HADAR

HADAR

Figure 29. (Continued).

109

k

SITE

110

HADAR

ENTRIES

Figure 30. NME AL 417-lh,:

idsble (tcale* - 1 cm).

111

HADAK

Figure 31. NME AL 438-lg, partial R mandible (scale = 1 cm).

HADAR

Figure 32. NME AL 441-1, partial mandibular corpus (scale ~ 1 cm).

HADAR

R

^HL*

mvL

V!||Mbj

$ "l -;

TW

ilpi111

<Jill £%L£B3jttg^Mg

Figure 33. NME AL 444-2, various elements of cranium, reconstruction, and partial mandible (scaks = close-up not to scale).

HADAR

113

HADAR

HADAR

Figure 33.

(Gmtixmed).

114

SITE

HAOAR

ENTRIRS

Figure 33. {Continued).

115

H A PAR

HADAR

Figure 33.

(Continued).

SITE

116

HADAR

ENTRIES

Figure 33.

(Continued).

HADAR

HADAR

Figure 34. NME AL 486-1, partial L lower face and palate (scales » 1 cm).

117

KANAPOI

LOCATION Fossil collecting area named for a dry wash between the Kalabatha and Kakuryo rivers some 38 miles W and 9 miles S of Tclckis Volcano at the southern end of Lake Turkana, northwestern Kenya (Map 2). DISCOVERY First hominid discovery made in 1965 by a team led by Bryan Patterson of Harvard University. Later hominids recovered 1994-97 by a team led by M. G. Leakey. MATERIAL Ward et al. (2001) list 47 hominid specimens from Kanapoi, all of them attributed to Australopithecus anamensis. Most of them consist of isolated teeth or tooth fragments, but the collection includes the holotypc mandible KNM-KP 29281, a substantially complete maxilla, some mandibular and maxillary fragments and several partial postcranial elements. DATING AND STRATIGRAPIIIC CONTEXT Lava capping fossiliferous sediments at Kanapoi was initially dated at 2.5 Ma by K/Ar (Patterson and Howells, 1967). The stratigraphy of the region was later clarified by Leakey et al. (1995), who reported a tripartite stratigraphic sequence, with two fluvial episodes separated by lacustrine deposits. Singlecrystal Ar/Ar dating of volcanically derived materials indicated that the full fossiliferous sequence bracketed

the 4.17-3.4 Ma interval. The hominid fossils were reckoned to be confined to the 4.2-3.9 Ma period. Later work (Leakey et al., 1998), including Ar/Ar dating (to 4.07 Ma) of a tephra (designated the Kanapoi Tuff), below which most hominids were found, suggested that all of the hominids except one came from sediments deposited between 4.17 and 4.07 Ma. The lone exception, the large mandible KNM-KP 29287, came from just above the Kanapoi Tuff, and was reckoned by Leakey et al. (1998) to be only "marginally younger." PREVIOUS DESCRIPTIONS AND ANALYSES The initial find at Kanapoi, of the distal end of a lett humerus, was initially assigned to Hominidae by Patterson and Howells (1967). However, it effectively remained in limbo until joined by the later findings of the Leakey team in 1994-97. The 1994 Kanapoi specimens were described by Leakey et al. (1995) as the holotype (KNM-KP 29281A) and hypodigm of the new species Australopithecus anamensis. This species was said by these authors to possess a mosaic of primitive and derived characters that did not exclude it from the ancestry of A. afarensis, while at the same time sidelining the recently described Ardipithecus ramidus (White et al., 1994, 1995) to sister status with respect to A. anamensis and all later hominids. In a commentary upon this paper, Andrews (1995) suggested that the earlier hominids from Kanapoi belonged to a "thick-enamelled homininc with jaws like fossil apes" (p. 556), whose

118

KANAI'OI

postcranium was unknown, while later Kanapoi fossils, together with slightly younger hominids from Allia Bay, belonged to a distinct "hominin with Homo-Wke postcrania" (p. 556). In 1998 Leakey et al. clarified the stratigraphy at Kanapoi, and demonstrated that all the hominids from this locality came from a single tightly constrained time interval (see preceding discussion). They thus reconfirmed their belief that all of these hominids belonged to the single species A. anamensis, which was "demonstrably more primitive" than A. afarensis (Leakey et al., 1998: 62) and was thus plausibly ancestral to the latter. Ward, Leakey and Walker (1999: 197) added that the "mix of features" in A. anamensis suggests that this species "belonged near the ancestry of" Australopithecus. These conclusions were maintained in these authors' subsequent monograph on the Kanapoi and Allia Bay fossils (Ward, Leakey and Walker, 2001), in which it was observed that "at present, there appears [sic] to be no autapomorphies precluding A. anamensis from the ancestry of A. afarensis* (Ward, Leakey and Walker, 2001:255).

MORPHOLOGY Material consists of a collection of fragmentary cranial and postcranial parts attributed to Australopithecus anamensis. KNM-KP 29281A and B consist of a mandible (KNM-KP 29281A, the holotype) and part of a L temporal bone (KNM-KP 29281B). A number of lower teeth appear referable to this taxon/morph, and one particularly unworn lower molar (KP 29287F) provides evidence of the kind of detail lacking in the type specimen due to dental attrition. Other clear-cut dental morphs can be delineated in the assemblage and will be presented as such below, but there are also numerous specimens that cannot readily be referred either to one of these morphs or to a morph represented at another site. The latter specimens will be listed separately. Unfortunately, in large part because so many teeth are too worn to be useful, it is not possible at present to link upper teeth with the holotype of A. anamensis, KP 29281A; this includes the two palatal halves that have been presented as a single specimen of A. anamensis, KP 29283. In another instance, however, an unworn upper (KP 34725G) and an unworn lower molar (KP 34725T), with the same kind and degree of cuspulation, cusp compression and continuous cresting system can plausibly be allocated to the same morph.

119

A. anamensis Morph (includes KNM-KP 29281, 29286F and G, 29287,30500 F and G, 31717B, 34725R, 31726,31730B, 37522) KNM-KP 29281 (holotype ofA. anamensis). 1. KNM-KP 29281A. L and R partial mandibular corpora, broken apart at symphysis and lacking rami. All teeth present. The anterior teeth, P2s, and M i s are very worn. The jaw is relatively long and narrow, especially anteriorly, with a fairly tight curve across the front. The cheek tooth rows are fairly parallel. The bone of the corpora begins to thicken laterally at about the region of M l . In profile the symphysis is very long. Its anterior surface slopes quite steeply backward, curving smoothly to an inferior margin lying below P 1 - P 2 . The symphyseal surface is essentially smooth. There is no sign of digastric fossae. The broken ramus began to rise around M 2 (M3 was probably masked). On both sides, a single large mental foramen lies below the septum between P2 and M l . Below each foramen, the inferior margin of the corpus is slightly thickened externally. Internally, the postincisal plane is long, almost horizontal, and extends almost to the level of P2; immediately below it is a damaged genial pit, inferior and posterior to which lies a well-developed inferior transverse torus (also broken). The mylohyoid lines are faint, and shallow submandibular fossae lie below the region of Ml—M2. Although worn, the l i s and I2s would have been quite tall; all have slighdy divergent sides, a shallow lingual curve and long roots. I2s are slightly larger than the l i s . The LC is broken; the RC very worn. The Cs were probably tall and projecting; a band of low cingulid extends buccally from what would have been a low mesial pillar, and widens around the base. Distally, there appears to be a small heel, which is the base of a worn margocristid that flows into a slightly expanded lingual swelling. Mesially, there is also a trace of a margocristid. The C root is quite long, stout, and slightly curved backward. The P i s are noticeably longer m/d than the P2s. The P i s are swollen buccally over the m/b-oriented root (giving an oblique orientation to their crowns). The P I crowns are very wide b/1 across the axis through the relatively low and essentially centrally placed protoconid. On both, a paracristid runs forward from the protoconid and kinks down and back to the base of the swollen lingual side of the tooth, producing a truncated and oblique m/1 surface that

120

Srn;

emphasizes the narrowing of the front of the tooth. The trigonid thus faces lingually and houses a pit infcriorly. Another crest runs d/1 from the protoconid, terminating inferiorly in a tiny swelling. Behind this low lingual swelling lies a shallow, small posterior fovea that is enclosed distally by a low cristid that originates somewhat buccally along the base of the protoconid. The P2s arc very worn and subsquare, with broadly rounded and swollen buccal sides and straightcr but d/1 obliquely oriented lingual sides. They have small, very mcsially placed mctaconids that lie opposite and lower than the originally large protoconids. Distolingually, behind the tiny mctaconid, lies a moderate talonid basin that is enclosed by a thick postcingulid that courses back and slightly lingually from the mctaconid, turns broadly at the d/1 corner of the crown and goes straight up the distal side of the tooth, terminating in a thickening on the distal side of the protoconid. The Alls are very heavily worn; the enamel may have been slightly wrinkled. The crown would have been roundedly rectangular, but possibly also with some distension at the back. The lingual cusps are rather bulbous and peripherally placed. The bulbous buccal cusps may have been more internally placed than the lingual ones. A deep crease separates the large and m/d long hypoconid from the smaller and mesiallv placed protoconid. A moderately deep and somewhat more open notch separates the subcqual mctaconid and entoconid. The metaconid is larger and m/d longer than the protoconid, and thus the entoconid lies distal to the hypoconid; the apex of the metaconid lies slightly mesial to that of the protoconid. A very broad hypoconulid probably straddled the midline of the crown; it is separated from the distally placed apex of the entoconid by a narrow notch. The talonid basin was probably restricted both m/d

and b/1. The M2s are somewhat worn; the enamel may have been slightly wrinkled. They are somewhat wider b/1 and longer m/d than the M i s , and have discernible vertical grooves around the hypoconid buccally. The lingual cusps were slighdy compressed and peripherally placed, whereas the buccal cusps were more internally placed. A stout paracristid runs from the midline of the base of the protoconid essentially to the buccal side of the base of the mctaconid, whose apex is slightly more mcsially placed than that of the protoconid. The large protoconid and smaller hypoconid are separated

ENTRIES

by a slight groove. A distinct notch separates the lan?e (especially m/d) metaconid from the smaller entoconid. The base of the entoconid lies slightly distal to the hypoconid. A deep groove separates the entoconid and hypoconulid. The triangular region of the hypoconulid is extremely broad distally, and the apex of the cusp seems to have lain a bit buccal to the midline of the crown. The talonid basin is very small and essentially restricted to the region around the bases of the metaconid and entoconid. There arc traces of vertical grooves on the buccal side of the tooth. The M3s arc longer m/d but slightly wider b/1 than the M2s. They taper slightly to their broadly rounded distal ends and arc deeply grooved on their buccal and lingual sides. The occlusal surfaces were minimally cuspulatcd. The lingual cusps are somewhat compressed and peripherally placed; the buccal cu?ps arc lower and internally placed. The m/d thick paracristid runs lingually from the middle of the protoconid to the mesial aspect of the base of the metaconid, thickening as it does so. The metaconid is slightly larger than the protoconid, especially m/d, and the apices of these cusps lie essentially opposite each other. Distal to the metaconid on the LM3 is a lower and smaller cusplike structure. Distal to this is another even lower and smaller cusplike structure, and then a larger cusplikc structure, subequal in size and height to the first of the series, that abuts the hypoconulid. On the RM3, there is one fewer cusplike structure lingually, which would suggest that on each M 3 there is a large metaconid (subdivided on the L) and a small, very distally placed entoconid. A deep groove separates the protoconid and hypoconid. 1 ne region of the hypoconulid is wide and subdivided by grooves; the cusp straddles the midline of the crown with something of a buccal extension. It appears that one can construct a morphocline of lower molar wear from the relatively unworn 29287F, through the more worn 34725R, to the quite worn type, 29281. Similarly, one can seriate the PjS in terms of increasing wear from 29286F and G, to 29287A and B, to 29281. 30050F and 29287E may also be included in this series. 2. KNM-KP 2928IB. The L temporal consists of the lower portion of the squamous with the mandibular fossa, which is very long a/p, wide m/l» quite shallow and flows smoothly into the bone in front with no articular eminence. Posteriorly, the fossa is only very shallowly bounded by the posteriorly strongly sloping, thick-boned face of the ectotympanic

KANAPOI

tube. It appears to have been confined to the cranial base (rather than extending laterally under the downwardly inclined posterior zygomatic root). The auditorv meatus was small, narrow and ovoid, and tilted forward. KiXM-KP 292S1C. Identified as a LI 2 , it could also be a RI2. It has a large compressed root, and would have been tall-crowned before wear. Its mesial edge is slightly divergent, while the upper part of the distal edge angles in strongly, cutting off the corner of the tooth. The lingual surface is shallowly concave. (D) is the crown identified as a RI2; it is similar to (C). (E) is a partial Rp! crown, comparable to that of 29281 A. (F) is a relatively unworn RM 3 missing its distal margin. It is highly cuspulated (but not in the same way as, e.g., 34725T), with an open talonid basin and buccal and lingual cusps that are subequal in height. The large protoconid and metaconid lie more or less opposite each other, and a fairly thick paracristid is wedged between their bases. The hypoconid is small and mesiaUy shifted relatively to what had been an m/d longer entoconid. There is a relatively m/d long, shallow, and open hypoflexid notch between the protoconid and hypoconid, and another broad and shallow notch between the hypoconid and what remains of the hypoconulid. The latter cusp was apparently somewhat b/1 broad and straddled the midline of the crown, albeit with some buccal emphasis. (G) is the d/b part of an LM3, plausibly ana mens is. (H) is part crown of lower LIl; highcrowned, with slight lingual curve. (/) consists of tooth fragments. Ki\\f-KP 292S6F and G. These are, respectively, a R and LP]. They are slightly larger than the P,s of 29281, but are similar in basic shape and morphology. Mesial and distal buccal pillars are present, as is a slight buccal cingulid around the base. The Pis are two-rooted, with the mesial root m/b positioned and the wide distal root b/1 oriented b/1. Both P2s are present and unworn. They have large, broad metaconids that are not as tall as the thinner, more peaked protoconid. They also possess a small distinct anterior fovea and a fairly large talonid basin. The buccal side is slightly swollen, and the lingual side markedly. KNM-KP 29287. Two partial mandibular halves {A is a L and B is a R) arc allegedly from the same individual. However, the symphyses do not match; when aligned with regard to the internal contour, the

121

two corpora are clearly different in a/p length along the symphysis. 29287 C—I includes some isolated teeth and fragments that are also said to be associated. /. L partial corpus A. The bone is moderately thick m/l and would have been very tall s/i (the base is missing). This would have been a long, narrow jaw. Judging from the preserved alveoli of 12 and C, the symphysis would not have been strongly sloping in profile. What is preserved of the postincisal plane also slopes downward quite strongly. The front of the jaw is narrowly curved across and the tooth rows are slightly divergent. The large mental foramen lies under the distal root of P2. The anterior root of the ramus took origin behind and well below M l , and may have been separated from M3 by a small gutter. The alveolus for the 12 is large, and that for the C is remarkably huge and its perimeter subcircular. The roots of P i are preserved, suggesting a similar outline to the PI in 29281A. P 2 - M 2 are present, largely unworn but variably broken. They look very small for the mandible. P2 has a very mesially placed, relatively large and bulky protoconid that is also fairly internally placed; there is a low buccal cingulid at its base. A much smaller and lower metaconid that lies opposite but quite separated from this cusp is very peripherally placed. A distinct but not very thick crest connects these two cusps. A very steep but not very m/d or b/1 expansive fovea lies mesial to the protoconid-metaconid crest and lingual to the apex of the protoconid. A low postcingulid courses broadly and arcuately distally and then buccally to terminate in a small but distinct hypoconid that lies at the base of' the m/d protoconid, thus far from the apex of this latter cusp. The postcingulid encloses a very shallow but quite expansive basin. The hypoconid is somewhat lingually placed; thus, the d/b aspect of the crown is obliquely truncated. It is conceivable that when worn down this tooth would have been similar to that of 29281A, which, however, lacked a hypoconid. The mesially damaged M l is somewhat broad but not very rounded distally. It preserves some buccal cingulid at the base of the protoconid, a relatively broad hypoflexid notch between the protoconid and hypoconid, a shallow vertical notch between the somewhat buccal-to-midlinc extension of the hypoconulid and the hypoconid, an m/d long and bulky metaconid whose contact with the somewhat small entoconid lies distal to that between the protoconid and hypoconid, and an m/d short and not very

JEL

12:

S i T i; E s

b/l wide occlusal notch between the cntoconid and the very broad region of the hypoconulid. It is conceivable that this tooth, when worn down, would have been fairly similar to that of 29281A. The even more mesially broken M2 is similar to the M l with regard to distal breadth and a more distal position of the contact between the bases of the mctaconid and cntoconid than that between the protocoled and hypoconid. The lingual cusps arc taller and more peripherally placed than the buccal cusps. A moderately thick paracristid wraps around the base of the metaconid.Thc hypoconulid is very broad, but not very long m/d; an m/d short but b/l moderately wide and somewhat deep groove lies internal to the edge of the crown and between much of the cntoconid and the adjacent portion of the hypoconulid. Buccally, a m/d moderately long but somewhat thin crest emerges from the buccal extremity of the hypoconulid, makes a fairly sharp corner, and proceeds mesially partway alongside the d/b side of the hypoconid. The lingual cusps are taller and more peripherally placed than the buccal cusps. Although lacking the vertical buccal grooves of the M 2 of 29281 A, it is conceivable that the M2 of 29287A, when worn down, would have been similar to that of the former. 2. R partial corpus B. This corpus is moderately thick m/1 and very tall s/i; the jaw would have been long and narrow. In profile, the symphysis had a moderate backward curve (but not as strong in 29281A). There is a tight curve across the front, and the tooth rows would have diverged slightly. The postincisal plane is moderately long, apparently extending as far back as PI, and it slopes quite strongly down. Infcriorly, there is part of what appears to be a R digastric fossa, which is oriented inferiorly and possibly also slightly anteriorly; it is bounded laterally by a raised margin. A huge mental foramen lies beneath the region or P 1 - P 2 . The anterior root of the ramus took origin below Ml and began to swell laterally below M2. Preserved in this partial corpus arc the alveoli for 11-12, C, the anterior root of M 3 , the partial roots of PI and the broken crowns of P 2 - M 2 , which are not very worn. 11-12 alveoli look large. Although the C area is broken, the root of this tooth was not as large as that of 29287A. In the P2 the protoconid is quite mesially placed and the subequal mctaconid lies opposite it. Both cusps are relatively peripherally placed; the region between them is broken. A stout postcingulid courses down from the apex of the mctaconid

T it i E

s

and proceeds distally and slightly lingually some distance before curving back strongly to run buccally and strongly mesially to the apex of the protoconid- it bears two distinct cuspulids and encloses a modcratelv deep, somewhat m/d long and b/l wide basin. Although the M l is very broken and what remains is displaced and spread apart, some details arc preserved. The bulkier protoconid (with a buccal cin^ulid at its base) and the more pointed and taller mctaconid were somewhat mesially placed. The former lay slightly more mesially than the latter cusp, and the groove between the bases of the protoconid and hypoconid, and apparently also that between the mctaconid and hypoconid, was well incised. The distal side of the tooth was broad and apparently not very rounded, and there is some marginal cuspulation along the region of the broad hypoconulid, as well as a small occlusal notch between the cntoconid and hypoconulid. Unlike those of 29281A and 29287A, the M2 tapers distally. Also unlike the type, this M2 bears buccal cingulids. The lingual cusps are, however, tall and peripheral, the buccal cusps are internal and low, and the distal margin is markedly cuspulated, with an occlusal notch between the entoconid and hypoconulid. Although this specimen is not the R counterpart to 29287A, it would appear that both corpora can be included in the morph represented by 29281A, and that they all contribute to a picture of variation within this morph. KNM-KP 30500F. An unworn LP t crown with a broken root; large but comparable to 29281. KNM-KP 30500 G. The broken crown of a RPi lacking its root; cf. 29281 and 29286. KNM-KP 31717B. A worn RM 3 fragment; anamemh.

d.

KNM-KP 3I71SA. A crushed lower (probably R) molar in a bone fragment; cf. anamensis. KNM-KP 34725 R. A somewhat worn RMi in a small fragment of mandibular corpus. It is similar to 29281A in having a mctaconid that is not much longer m/d than the protoconid and whose apex lies only slightly mesial to that of the latter cusps; a moderately thick paracristid that emerges mesially from the base of the mctaconid and courses buccally to fade on the base of the protoconid mesially; a distinct buccal cingulid; a hypoconid that, although shorter m/d than the large entoconid, lies apically

KANAPOI

slightlv mesial to it; and a subdivided, moderately sized and wedge-shaped hypoconulid that more or less straddles the midline of the crown, with a slight buccal extension. Also, the chunky-looking crown, which is somewhat wide b/1, is roundedly rectangular and broadly but shallowly arcuate around its distal side; cf. anatnemis. KNM-KP 31726. A small, damaged, and worn R))2; plausibly anamemis. KNM-KP 31730/s. A worn and broken RP,; cf. anamemii. KNM-KP 37522. Fragment of a lower L molar; cf. anamemis. KNM-KP 29286C Morph (includes KP 30500) KNM-KP 2V2H6C. This is a small LM, that is much smaller than the attributed M2s KP 29286 ID and I, and is morphologically dissimilar to them. The buccal cusps arc low, somewhat bulbous and internally placed; the lingual cusps are less so, but are still a bit internally placed. All four cusps are subequal in size, but the buccal cusps are slightly taller. The apices of the buccal cusps lie slightly mesial to those of the lingual cusps. An m/d short paracristid descends from somewhat below and just lingual to the midline of the apex of the metaconid, and fades out quite low down before reaching the midpoint of the protoconid base. A lairly marked cingulid lies high up on and completely surrounds the base of the protoconid. Deep vertical grooves, which make the crown appear partially waisicd, lie between and partially separate the prouicnnid from the hypoconid (whose bases extend Hngiully beyond the midline of the crown) and the (consequently b/1 constricted) metaconid from the entoconid. The entoconid and hypoconid arc truncated distally by somewhat pronounced and deep b/1-orientcd anil b/1 wide pits (more marked on the entoconid), and thus appear to be unusually mesially placed, These pits lie on either side of a somewhat large, centrally placed hypoconulid. The talonid basin is restricted m/d and displaced lingual to the midline of the tooth. KNM-KP 30500. R and L mandibular fragments and associated lower teeth. (//) is a partial L corpus with worn and weathered M 1 - M 2 . Both Ms are *uhrcctaugular, and were moderately cuspulated. M2 i* larger b/1 and m/d than M l , with more extensive

123

buccal cingulids around the protoconid and between the hypoconulid and entoconid, and more pronounced notches between the protoconid and hypoconid and hypoconid and hypoconulid (the latter notch truncates the hypoconid distally and makes it appear to be mesially placed; cf. 29286C). M 1 - M 2 buccal cusps lie slightly internally, the lingual cusps arc somewhat taller and more peripherally placed, the protoconid lies slightly mesial to the metaconid, and the talonid basins arc quite expansive. On both Ms the somewhat wedge-shaped hypoconulid is very wide and more or less straddles the midline of the crown, and on each tooth a crest connects the entoconid and hypoconulid. (/J) is a somewhat damaged and worn LM> If it is associated with (A)t it is small relative to M2. This tooth is small, m/d long, b/1 narrow, distally tapering and moderately cuspulated. It has a grossly beaded buccal cingulid on the protoconid and at the base of the notch that intervenes between the hypoconid and hypoconulid; there is also a small notch between the protoconid and hypoconid. What is preserved of the metaconid is taller than the not very internally placed buccal cusps. The protoconid lies slightly mesial to the metaconid. On M2 and M 3 , at least, there is evidence of a moderately thick paracristid that courses from the protoconid down to the mesial side of the base of the metaconid; on M2, it becomes thinner as it approaches the metaconid. (C) is a R mandibular fragment with a broken, weathered and very worn M l , which appears comparable to the M l in {A). (D) is a broken, weathered and relatively worn RM2 with some adherent alveolar bone; it is comparable to (/I). (E) is a broken and somewhat worn RM 3 comparable to (/i). Taung Lower Dental Morph KNM-KP 31729. A very small and worn lower Rdm2. There are three crests between the broadly separated protoconid and metaconid, giving this specimen the "twin basin" Taung lower dental morphology, and a relatively large metastylid lies distally on the metaconid. The somewhat internally placed hypoconid is large and lies mesial to the peripherally situated and conical entoconid. There is a moderately broad but not very deep hypoflcxid notch and a deeper and somewhat narrower notch between the buccally shifted, but not very distinct hypoconulid and entoconid. The talonid basin is restricted m/1 and confined lingual to the midline of the tooth. I he

124

SITE

somewhat broadly rounded distal portion of the tooth is slightly wider b/1 than the mesial part. Melka Konture Lower Dental Morph (includes KNMKP 29286D and 1,30502D and E, 31712J and K) KNM-KP 29286D and /. The cusp configuration of these lower M2s also differs significandy from what is seen in 29281. The enamel is slighdy cuspulated and bears vertical grooves on its buccal side. The buccal cusps are somewhat internally placed, whereas the lingual cusps are quite peripherally situated. The somewhat b/1 narrow but m/d long tooth tapers distally, especially because of b/1 truncation of its buccal side. The tall metaconid is longer m/d than the lower protoconid; the apex of the somewhat b/1 compressed entoconid lies distal to the m/d truncated hypoconid. As especially seen on the L, a very m/d thick paracristid emanates from the apex of the protoconid and courses down and lingually to wrap almost fully around the base of the metaconid, becoming thinner as it proceeds. There is a cingulid around the base of the protoconid that thickens distally, and a fairly deep hypoflexid notch separates this cusp from the hypoconid. The m/d narrow, parallel-sided and very buccally placed hypoconulid lies close to the base of the entoconid. A groove that emerges from the m/d restricted talonid basin courses only about halfway up between the bases of these two cusps, and a slight buccal cingulid lies low between them. Distally, more or less in the midline of the crown, is a deep, quite b/1 broad and rather m/d long fovea that emphasizes most of the distal sides of the entoconid and hypoconulid; the distal margin of this fovea is bounded by a thick cristid. Although this is a permanent tooth, the striking morphology of, for ettir.pJe, the hypoconulid region and of the par^riitid can be accommodated in a size-shape gradient iviih the dm 2 of Melka Konture and other -:jw inserts allocated to this morph (see discussion). Ihc definitely associated M3s are similar in many ways to the M2s, but are narrow m/1 and more broadly rounded distally. Their less worn occlusal surfaces are moderately cuspulated. The metaconid on each is tall and pointed, while the somewhat internally placed buccal cusps, especially the protoconids, are more compressed, as are the entoconids. The thick paracristids thus appear more confluent with the protoconids, and, although thinning lingually, these crests remain thicker throughout their lengths. The

ENTRIES

protoconids are longer m/d than on the M2s. The entoconids are thus more distally placed (almost opposite the subequal entoconids), and the hypoflexid notches between these buccal cusps are longer m/d and shallower. The hypoconulid on LM3 is more similar to the configuration on the M2s, but this cusp is smaller, more wedge-shaped, and the fovea is smaller though still deep. Also, lingual to the fovea is a series of well-developed cuspulids along the distal edge of the crown. On the RM3 there is no distal fovea; instead there is the buccally placed, wedge-shaped hypoconulid and, lingual to it, a series of cuspulids. On both M3s there is a small buccal cingulid at the juncture of the bases of the hypoconid and hypoconulid. KNM-KP 30502D. This is a somewhat damaged and worn tooth identified as a RM 3 , but that it probably a Rdm 2 . It is cuspulated, with high lingu.J. cusps. A relatively thick paracristid coursed straigh; across between the protoconid and metaconid, whosr apices lie opposite each other. The metaconid was m/d longer than the protoconid. The hypoconid and entoconid are smaller but subequal in size; the latter cusp lies distal to the former. A somewhat roundedly rectangular, very buccally placed and moderately sized hypoconulid is separated from the entoconid by a deep, fairly b/1 wide, and d/1-oriented basin that is bounded distally by a crest; another crest descends from this one into the basin. There is a somewhat shallow vertical groove buccally between the hypoconid and the hypoconulid and another, occlusaUy, that extends only partway up from the talonid basin. KNM-KP 30502E. This is a relatively unworn LM 3 crown missing much of its mesial portion. It is somewhat cuspulated, with a cingulid on the protoconid and an open talonid basin. The cusps are set far apart and are not very different in height. The metaconid was m/d longer than the protoconid and the small entoconid lies distal to the hypoconid. The moderate-sized, subrectangular hypoconulid is very buccally placed, and a crest extends from it to the entoconid distally, behind a fairly deep, b/1 wide and d/1-oriented basin that intervenes between these two cusps. KNM-KP 317J2J. A minuscule lower Ldm 2 . The lingual cusps are somewhat peripheral and higher than the buccal. The occlusal surface is cuspulated,

KANAPOI

with distinct cusps, a well-developed but not continuous buccal cingulid, and a thick paracristid that emerges mesially from the base of the protoconid and courses to the low metaconid. The apices of the protoconid and metaconid lie opposite each other, but the latter cusp is longer m/d and thus the marked crease between this cusp and the entoconid behind lies distal to the equally marked crease between the protoconid and hypoconid. The very buccally placed, subrectangular hypoconulid is separated from the hypoconid by a crease, at the base of which is a moderate, beaded buccal cingulid. The base of the hvpoconulid extends lingually and slightly mesially to contact the internal aspect of the entoconid. A deep, moderately b/1 wide and moderately m/d long distal basin, whose margin is almost completely crestlike, lies between the hypoconulid and the entoconid. KNM-KP 31712K. A Rdm 2 that is the mirror image of 31712J. Nonhominid?/Dentally "Pongo-Kke" KNM-KP 30498B. A very worn RC 1 crown with a moderately stout root, and possibly subequal and broadly divergent mesial and distal edges as well as a mesial margocrista. The crown would have been quite short, and about as wide b/1 as long m/d. KNM-KP 3J7J7A. A L M 3 that is rounded distally, with peripheral buccal cusps. KNM-KP 31723. A worn crown of RM 3 , with buccal grooves that had probably been cuspulated. KNM-KP 34725. (G) is a R, possibly unerupted, upper molar crown that is low crowned with a very well-cuspulated (and thus fllled-in) occlusal surface and wrinkling even around the sides of the tooth. This low-crowned tooth is somewhat long m/d, and thus appears roundedly rectangular. T h e cusps are compressed, internally placed (the lingual cusps most so), and confluent with an arcuate cresting system that completely rings the trigon and talon basins. These basins are almost confluent, being minimally separated by a very low postprotocrista that courses from just below the apex of the protocone and only partway up the midline of the metacone. The paracone is large and especially buccally swollen, whereas the much smaller metacone gives a truncated appearance to that region of the crown. T h e prcprotocrista swings out mesially before curving back

125

in to merge with the side of the paracone. Just where these structures come together, a short, moderately thick crest runs along the mesial side of the base of the paracone. The postcingulum courses almost directly back and then curves strongly buccally, to curve into and become confluent with the metacone. A semibcaded lingual cingulum courses completely around the side of the very large and m/d long protocone, and continues partway along the face of the relatively large hypoconc. (J) is a very highcrowned LIj with minimally divergent edges and a well-curved lingual surface with a low heel, very reminiscent of that is seen in orangutans. ( / ) is a partial RI 2 . (N) is part of a LPj crown; the mesial edge is slightly longer than the distal edge and there is a large shallow trigonid and a deep talonid basin. (0) is a broken, highly cuspulated RP2 crown with a large anterior and a larger posterior fovea, and a cristid between the apices of the low, widely separated protoconid and metaconid. (T) is a m/d long, moderately b/1 narrow, distally rounded and highly cusuplated (and thus somewhat occlusally filled-in) L M 2 or M 3 with a semibcaded buccal cingulid and some buccal vertical grooving. T h e crown tapers slightly distally. The cusps are compressed and incorporated into a cresting system that completely rings the occlusal surface, enclosing a very m/d long and somewhat expansive basin. There is a hint of a crest, coursing directly between the opposite-lying protoconid and metaconid, that creates a large basin between it and the paracristid in front. The metaconid is much longer m/d than the protoconid, and the hypoconid lies well mesial to the entoconid. T h e region of the hypoconulid is thus quite b/1 wide. Just distal to the entoconid are two distinct "finger-like" projections (created by grooves in the enamel) that point m/b (in contrast to the RM], 34725, which has subdivisions of the hypoconulid distal to the hypoconid). KNM-KP 35839. (A) is a pathological LI 1 whose short crown is somewhat expanded beyond the root mesially, and excessively so distally. The crown is spatulatc, somewhat concave lingually with grooves, and bears margocristac. (/?) is a partial RC 1 . It is identified as being from a male, but could even more plausibly be a female (cf. C dimorphism in Potigo). It has a moderately tall crown with subequal mesial and distal edges that are moderately divergent, and that terminate buccally in short pillars, the mesial being

126

SITE

the more prominent. Lingually, the crown is slighdy curved with a basal swelling and mesial and distal margocristids. The root is stout. (C) is a broken, somewhat cuspidated LP 1 with a low protocone that is well separated from the paracone. KP 35840B. This is a very cracked and somewhat worn partial L upper molar crown that is morphologically very reminiscent of 34725G, a R M \ in having compressed and internally placed cusps that are confluent with a cresting system that rings the expansive but somewhat shallow trigon basin, a lingually sloping and truncated metacone, and lingual cingulum that extends from the protocone partway onto the hypocone. KXM-KP 35852. Listed as a worn and weathered male L C \ but cf. 35839B discussed earlier. Unassignable to Morph KSM-KP 29286. Lower dentition in several fragments (A-J), with matrix often adhering. All are allegedly associated (but see the 28286C morph). In each, the enamel is clearly thick, but it is unlikely that all represent the same morph. However, aside from 292S6C, these specimens are difficult to allocate to a morph based on cheek-tooth morphology. One fragment contains RI2 and a huge alveolus for the C root. R and LL2 are heavily worn. The RC is barely worn, and the preserved portion of its root is very stout; the crown, however, is thin and relatively short. In buccal profile die mesial ed^e is short, sloping; the mucn longer; almost vertical distal edge terminates in a small heeL The buccal surface is strongly curved m/d as well as vertically to the apex. Buccally, there is a thin mesial pillar and a hint of a basal cingulid. A strong lingual pillar is distaHy set behind a thick, mesially angled margoaistid that is accentuated by a vertical sulcus. A thin vertical groove delineates the back of mis pillar. A damaged and worn L C : (KNMKP 292S6F) is probably not associated. KSM-KP 292X2. A very worn lower L M l or M 2 (probabSy the former). KSM-KP 29283. R and L maxillary halves (A 2nd &, respectiray), allegedly assodaied. Both mzriHae are *A aod -,-. eroded and the teesh are extremely w; worn. O a die R mrrvhj aa II 2nd C 2ie gjued in; P 1 - M 2 are m place. O n the L, C - M 3 are in place. There are also two roots ©f very worn reesh {KP

ENTRIES

29283d RI 2 ; KP 29283d: LI 2 ), which also may not be associated. Although the maxillae arc almost completely complementary, they arc probably from two different individuals. 29283A extends to the midline wh'l 29283B extends slightly beyond the midline, the palate of 29283A is thinner overall than in 29283Bthe preserved corners of the L and R nasal margins are very different, and the two halves do not join precisely. Also, if one orients them based on the contact at the front, the upper jaw appears rather broad much more so than one would expect from looking at the lower jaw. The nasoalveolar clivus on both sides slopes strongly forward and runs smoothly into the nasal cavity. The posterior pole of the clivus in both halves lies well within the nasal cavity; beneath it runs a long, somewhat large incisive canal that opens below, at the level of P I . The canal is much bigger in (2?). The posterior pole extensively overlaps the palate in both specimens. Behind the pole is a minor step down to the posterior nasal floor; this is more pronounced in (B). In both {A) and (#), the palate is thin underneath the clivus, and thickens rapidly posteriorly. In (B) a thin but distinct groove continues forward on the palate toward the incisor region; this groove is broader and shallower in (/I). There is no distinct margin to the nasal aperture on either side. T h e inferolateral corner of the aperture in 29283A is more steeply curved; its counterpart in 29283B is somewhat damaged but is more vertical. In both, the lateral margin of the aperture appears as a smoothly curved pillar. This pillar is more vertical in 29283A; it slopes back somewhat in 29283B. In 29283A the pillar is delineated posteriorly by a very deep, expansive fossa; in 29283B the fossa is smaller and shallower. In both, the palate is shallow and the lateral walls are steeper posteriorly than anteriorly. In both, the palate slopes extremely gently at the front Posteriorly, 29283B is deeper than 29283A- The maxillary sinuses extended posteriorly only to the level of M 2 w 29233A, but penetrated anteriorly into the facial pillar. In 29283B the maxillary sinus extended back oyer M 3 , but only up to the pillar anteriorly. The anterior root of the zygomatic arch is not preferred in either fragment, but in 29283A it evidently did not a n * low down* In both, the tooth that is glued in as 11 has a long. stout root; the alveolus for 12 suggests the *arnr> In both, the C that is glued in ippvently has a ]oa& stout, backward!}* curving ro*A; in anterior view it also

K A N»;T AI»OI

curves laterally (thus the crown would have been deflected outward). In (A) and (£), the PI has two divergent roots. It is swollen buccally and is larger than the P2; these teeth are slightly larger, however, in (B). In (A) and (/?), the M l metacone is larger than the paraconc, and the reverse is true of M2. (B) preserves evidence on M 1 - M 2 of a thick postcingulum that coursed straight up the distal side of the tooth from the Inpocone to the distal side of the metacone, where it terminated in a small but well-defined style; it is also clear that the cusps of at least M2 had been distinct and not compressed. In (B), which preserves the M 3 , the metacone of this tooth is larger again. In (A) and (£), M l is smaller than A12, with a relatively undistended h}*pocone region that is very large in M2. Also in (B)y M3 is at least as large as M2, and is distally rounded. Clearly, very little informative tooth morphology is preserved. KNM-KP 29284. {A) is a R developing C, crown (similar to unworn 29286), and (B) is a RP, crown with very crisp features and distinct mesial and d/b pillars, with the distal pillar extending lingually as a small heel. KNM-KP 30498. Fragments of a maxilla with teeth, plus various isolated teeth, many very fragmentary. {A) is a tiny L maxilla fragment with the compressed root of an 12 and a very heavily worn, broadly spatulate and short-rooted I I . (C) is a tiny maxillary fragment with a very worn and weathered RP 1 that has a long, sloping mesial edge and a shorter, steeper distal edge and slight buccal and lingual bulge. The paracone and protocone are well separated. (D) is a bit of maxilla with a broken but not very worn LM 3 , somewhat cuspulated occlusally. There is some slope to, and grooving of, the buccal side. ( £ ) is said to be a R maxillary fragment, but is from the L, with an M 3 that is strongly cuspulated with lingual grooves. It is pearshaped in outline, broad lingually. (F) is a maxillary fragment with divergent roots of P 2 and a worn M 1 . The M 1 lingual cusps are peripheral and compressed, the hypocone and postcingulum arc lingually swollen, and the protocone is not very internally placed. (G) is a RI2 partial crown with a broken root. ( / / ) is a M fragment. (/) is the buccal half of a very worn RP 2 crown. ( / ) is an LP! fragment. (K) is a C fragment. (L) is a broken molar root. (/?) is referred here to the nonhomimd/Porigo-Wkc morph.

127

KNM-KP 30502. Associated fragments of loxver teeth (A) \s a fragment of a LP2; (B) is a fragment of a KM,; (C) ,s a fragment of a RM2. Sec Mclka ivonturc morph for (D) and (£). KNM-KP 31712. A juvenile mandible, isolated teeth and tooth fragments, not all of which represent the same morph. {A) is a very small fragment of corpus, with damaged d m l - d m 2 and developing successor crowns buried in the matrix, dml had a long, deep, teardrop-shaped, centrally placed talonid basin, and probably also a long, centrally placed trigonid basin. The central placement and size of these basins is unusual. (B) is a fragment of the lateral side of a quite deep R corpus with a mental foramen. (D) is a tiny Ldrri! lacking the mesial portion. The lingual cusps would have been peripheral and taller than the buccal cusps. The preserved distal faces of what must have been a tall metaconid and protoconid are steep and quite vertical; their oblique orientation suggests that the protoconid was placed at least somewhat mesial to the metaconid. The hypoconid is large and lies quite mesial to the much smaller entoconid. The region of the hypoconulid, which appears to be subdivided into two moundlike swellings, is very lingually placed and is separated from the hypoconid by a large wedge-shaped notch. This is unlike anything else so far seen. (I) is a RC, crown, with a distal pillar with a thin groove behind, and a long, mesially flexed anterior edge. Other fragments with this number include (C) (broken di2, with bone adherent); (E) (unerupted partial I, crown, lingual surface curved); {F) (fragment of an I, crown); (G) (mandibular fragment with LI2 erupting and a C crypt); (//) (part of I 1 , a little spatulate); (L) (eight mandibular fragments); (M, N, 0) (not present); (P) (C fragment); (Q) (C fragment). KNM-KP 31713. {A) is a small R mandibular corpus, lacking the ramus but preserving alveoli for L I 2 - R I and roots of R C - M 2 . This jaw is small and s/i shallow, although shallower at the symphysis than further posteriorly. It is fairly broad for its depth. The symphysis is flat across, but in profile curves smoothly and quite strongly back. Internally, the postincisal plane is somewhat sloping and quite short, and then descends steeply down to the large and inferiorly placed genial tubercles. The absence of a genial pit suggests lack of development of an inferior transverse torus. There appears to be a well-developed submandibular fossa that extends all the way forward

]28

SITE

to the genial tubercles. There is no trace of a digastric fossa. The anterior root of the ramus takes origin toward the rear of M2, and close to the alveolar margin. The 11-12 alveoli are not markedly compressed, nor arc they long. The C root was long and stout. The PI crown was m/1 oriented, and probably longer m/d than P2. The configuration of the symphyseal section and internally of the corpus behind is noticeably different from KP 29281. (B) is a fragment perhaps of an upper C crown. (C) consists of fragments of an uncuspulatcd molariform tooth. KNM-KP 31714. A weathered Ldm2. Plausibly like the small molars from Allia Bay. KNM-KP 31727. A damaged RC^ with a deep distal grove and a small heel. KNM-KP 31728. A broken lower L molar. Smallish; cf. the tiny teeth in this sample. Cuspulated. KNM-KP 34725. {A) is a Ldi2; could be upper or lower. (B) is a Rdq, with a long root and a lingual pillar with a deep groove behind and a shallow depression in front. (C) is a worn L d q . (D) is a dm^ probably R, with subequal trigonid and talonid. (Z.) is a RCj fragment with a deep distal groove and part of a lingual pillar. (A/) is part of a LCj with a deep distal groove. (£/) is a very thin occipital fragment. (V) consists of cranial fragments; adult but very thin boned. (£, F> Hy K, P, Qy S) are uninformative tooth fragments. (R) is referred here to the anamensis morph, and (G, /, / , N, O and T) to the nonhoiTUnid/A?/7£0-like morph. KNM-KP 35840. (A) is listed as a L tooth, but is either a RM 3 or possibly dm 2 . This is a roundedly subsquarc tooth with some distal swelling of the relatively large hypocone, and some lingual distension of the very large and somewhat mesially shifted protoconc The fairly large metacone and the smaller paracone lie buccaUy and level with one another, although each swells out slightly buccally. The trigon basin is very large and deep, although truncated a bit by the moderately internally placed protocone; the hypocone is also somewhat internally placed, thereby truncating b/1 the deep talon basin. There is a noticeable lingual slope. There is a series of cuspules in the basin (one or two mav be vestiges of a postprotocrista) that only slighdy disrupt the confluence of the two basins. A twinned crest courses from the buccal side of the protocone to the lingual

ENTRIES

side of the paracone; they are separated by a deep bi thin groove. A very thick postcingulum courses almost direcdy buccally from the distal side of the mpoconc to the distal side of the metacone, from which it U separated by a groove or notch. A broad notch lie between the bases of the protoconc and hvpoeone on their sloping lingual sides. There is a small but deep protostylar pit on the mesial side of the protocone and some lingual cingulum. Unlike anything seen so tar. (C) is a partial molariform crown with an internally placed protocone, a long sloping lingual surface and a welldeveloped protostyle and possibly a well-developed hypocone; listed as a suid, it is probably a primate. KNM-KP 30500, 30505(A, B), 30504. 31372, 31715(A-C), 31716(A-C), 31717C, 31718B. 31719. 31720, 31721(A. B), 31730A, 35841, 35844, 35845, 35650. Various tooth fragments. KNM-KP 35847. L lower M with a damaged and worn crown. The buccal cusps are huge and the mesial roots bifid. KNM-KP fragments.

35851,

37523. Cuspulated

molar

REFERENCES Andrews, P. 1995. Ecological apes and ancestors. Nature 376:555-556. Leakey, M. G. et al. 1995. New four-million-ycar-old hominid species from Kanapoi and Allia Bay, Kenya. Nature 376:565-571. Leakey, M. G. et al. 1998. New specimens and confirmation of an early age for Australopithecus anamensis. Nature 393:62-66. Ward, C. V., M. G. Leakey and A. Walker. 1999. The new hominid species Australopithecus anamensis. Evol. Anthropol. 7:197-205. Ward, C. V., M. G. Leakey and A. Walker. 2001. Morphology of Australopithecus anamensis from Kanapoi and Allia Bay, Kenya./ Hum. Evol. 41:255-368. White, T. D., G. Suwa and B. Asfaxv. 1994. Australopithecus ramidusy a new species of early hominid from Aramis. Ethiopia. Nature 371: 306-312. Also corrigendum, Nature 375: 88,1995. Repository National Museums of Kenya, PO Box 40658, Nairobi, Kenva.

129

KANAPOI

•r

"ttf

feta

KANAPOI

Figure 1. KNM-KP 29281A, partial R and L mandibular corpora (scales - 1 cm).

k

130

SITE ENTRIES

v ^ f B •.' •c2'

'•'"•"•''j^am»

B&

Oil

& I^WL -T i&ffixwm'jliKaisi^ w&» ^SPIfe'^ ^Sifc^^t^^m ">! ^ ^ ^ ^ B B

KANAPOI

• •

Figure 2. KNM-KP 29283, R and L partial maxillae (scales = 1 cm).

KAKAPOE

KANAPOI

Figure 2.

{Continued).

131

i

132

SITS ENTRIES

KANAPOI Figure 3. L composite: KNM-KP 29286F, lower L PI; 29286G, lower RP1,29286C, lower L molar. Mid-

dle composite, lower molars. Top row: KNM-KP 292861; Bottom row: 29286D. R composite: Top row, lower molar* KNM-KP 34725T and R; Bottom row: 34725G, upper R molar, and 347251, lower RI2 (scales = 1 cm).

KANAPOI

133

KANAPOI

Figure 4. KNM-KP 27287A and B, L and R partial mandibular corpora (scale = 1 cm).

SITE

134

KANAPOI

ENTRIES

Figure 5, KNM-KP 29287A, L mandibular corpus (scales * 1 cm).

KANAPOI

KANAPOI

Figure 6. KNM-KP 29287B, R mandibular corpus (scales = 1 cm).

135

136

Sitfc

ENTRIES

^•^i

Rj^HB^

B^

\* 11 JRIRVM!! HF-^xB

UJ ;

KANAPOI Figure 7. Lingual (L plate) and buccal views of upper canine KNM-KP 29287C (on L in each view) and upper incisor KP 30498B (scales = 1 cm).

KANAPOI Figure 8. Top row, L to R: KNM-KP 30498A, upper I; 30498D, upper C; 30502D, lower R molariform. Bottom row, L to R: KP 30498B, upper P; 30498E, upper molariform; 30502E, lower L molariform (scale = 1 cm).

L

KJUVAPOI

Figure 9. KNM-KP 30500A and B, L parM nundibk (scale = 1 cm). KAXAFOI

137

Figure 10. Lower R mains. From L to R: KNM-KP 3O5G0C, D and E (scale = 1 on). KAXAPOI

Figure 11. Top L: KNM-KP 30500F, lower LPl; Top R: KP 29287E, lower RPl; Bottom: KP 29287G, lower KM (scale = lcm). KANAPOI

138

SITE

ENTRIES

Figure 12. KNM-KP 31712. Top 1 31712J, lower Ldm2; Top R: 31712K, lower Rdm2; Bottom:: lower Ldml (scale = 1 cm). KANAPOI

KANAPOI

KANAPOI

Figure 13. KNM-KP 31713, partial R mandibular corpus (scales m 1 cm).

139

SfT& E m m i e *

140

KAHAFOI

Figure 15, Lt (scales = 1 cm). KAXAFCH

KAWAFOI

Figure 14, KNM-KP 31729, lower RMl (scale * 1 cm)

[L) and buccal iriews of KNM-KP 35839A, upper incisor, and 35839B, upper canine

Figure 16, From L to R; KNM-KP 35840B, A and C, upper filariforms (scale = 1 cm).

(East Turkana, East Rudolf)

KOOBI FORA

(or Paranthropus) boisei include the crania KNM-ER 406 and 732, the partial cranium KNM-ER 13750, the calvaria KNM-ER 407 and the mandibles KNMER 729,1477 and 3230. One additional specimen (the partial cranium KNM-ER 2602) has been referred by Kimbel (1988) to Australopithecus afarensisry yet others are referred by Wood (1991) simply to Australopithecus sp. indet. In the same publication Wood rejected the notion that Australopithecus africaniis is represented at Koobi Fora.

LOCATION Collecting area to the east of Lake Turkana, northern Kenya (Map 2). The name Koobi Fora originally applied to a specific lakeside feature, but has now come to refer to the entire area of exposures, formerly known as "East Rudolf" or "East Turkana," that extends south along the eastern shore of Lake Turkana, from Ileret in the N to Allia Bay in the S. DISCOVERY The fossiliferous potential of this area was first identified by R. Leakey in 1967. From the first organized expedition in 1968, until the early 1980s, thousands of mammalian fossils, including many hominids, were recovered by collectors under the direction of R. Leakey and G. Isaac.

DATING AND STRATIGRAPHIC CONTEXT The Koobi Fora fossils are mostly surface finds, in a series of lacustrine and fluvial deposits that are interspersed with numerous volcanic tuffs that have provided the markers for stratigraphic reconstruction. A complex history of local faulting exacerbates problems of correlating individual tuff exposures, and together with some problematic radiometric dates, plus an initial failure to record exact locality information (specimens were at first referred simply to numbered collecting areas), this led to some dispute over the exact antiquity of some important hominid specimens, including ER 1470 (see accounts in Lewin, 1987; Tattersall, 1995). The introduction of techniques for identifying the tuffs from specific eruptions by their "geochemical fingerprints" (e.g., Ceding and Brown, 1982) permitted resolution of many of these problems by F. Brown, C. Feibel and their co-workers, whose painstaking studies (e.g., Brown et al., 1985; Brown and Feibel, 1986; Feibel, Brown and McDougall,

MATERIAL Between 1968 and 1982, over 170 hominid fossils were recovered. These ranged from isolated teeth to entire crania and a partial skeleton. Further hominids were reported by Leakey and Walker (1988). A complete listing (to 1985) is given by Day (1986), and cranial specimens have been comprehensively monographed by Wood (1991). Specimens found include both robust australopiths and specimens attributed to Homo (for the latter, see Volume 2 of this series); all are referred to by their Kenya National Museums (KNMER) catalog numbers. Well-known examples of Koobi Fora robust specimens allocated to Australopithecus

141 •

v.

142

SITE

1989) have greatly clarified the stratigraphic sequence. These same authors have also reidentified the hominid find sites and fixed their positions within the revised stratigraphy by relating them to identified marker beds. All of the Koobi Fora deposits of interest here arc now assigned to the Koobi Fora Fm (which includes the Kubi Algi and Guomde Fms recognized earlier). Within a total sediment thickness of almost 600 m, eight members arc recognized in this Formation, each identified by designated tuffs. Three stratigraphically contiguous members, the Burgi, KBS and Okotc, which together span the period from about 2.7 Ma to 1.4 i\la, have produced almost all the Koobi Fora hominid cranial and mandibular specimens relevant here. Indeed, hominid fossils arc almost absent from the lower parts of the Burgi, so that nearly all those known date from between about 1.9 and 1.4 Ma. Among the better-preserved cranial specimens usually attributed to Australopithecus (or Paranthropus) hoisei, KNM-ER 23000 is dated to about 1.9 Ma, and KNM-ER 406, 732 and 13750 to about 1.7 Ma. Among the more complete mandibles, ER 1477 dates to just under 1.9 Ma; ER 3230 to about 1.65 Ma; and ER729tojustovcrl.5Ma. As noted earlier, one australopith specimen reported from relatively low in the Koobi Fora Fm is not believed to represent Australopithecus (or Paranthropus) hoisei.Thk is the KNM-ER 2602 partial cranium, reported but not referred to taxon by Leakey and Walker (1985), that Ki mbel (1988) assigned to Australopithecus afarensis. This comes from the Tulu Bor member, just above the Tulu BorTuff, whose age is constrained to about 3.35 Ma (Brown et ah, 1985). At about 3.25 Ma (Fcibcl, Brown and McDougall, 1989), ER 2602 is thus significantly older than the bulk of the Koobi Fora hominids.

ARCHAEOLOGICAL CONTEXT Stone tools arc known from a variety of sites at Koobi Fora. From the famous KBS tuff itself (1.88 Ma) come tools of the "KBS industry," essentially an expression of the Oldowan, consisting of chipped cores and flakes (Isaac et al., 1971). Slightly later, in the lower part of the Okote Member (ca. 1.6 Ma), are found lithics of the Karari industry, which adds large core scrapers to the earlier toolkit (Bunn et al., 1980). Indeed, there is an apparent trend over time at Koobi Fora for toolkits to include larger cores and more

ENTRIES

numerous retouched forms (Bunn et al., 1980). At th very end of the sequence there is one carlv Acheule site (Schick and Toth, 1994). Koobi Fora has fu nished a number places on the ancient landscape at which hominid activity was evidently concentrated1 beyond direct cut-mark evidence of butchering, clement frequencies indicate that some ancient hominids obtained parts of relatively fresh carcasses and transported them to such places for processing and consumption (Bunn, 1986). However, several kinds of hominid were present on the East Turkana landscape between about 2.0 and 1.5 Ma, and there is no firm evidence to connect any particular type of hominid to the toolmaking activity.

PREVIOUS DESCRIPTIONS AND ANALYSES From the beginning of the fieldwork at Koobi Fora, regular annual reports (e.g., Leakey, 1972, 1973, 1974; Day ct al., 1976) contained brief descriptions of hominid fossils as they were found, including those ascribed to Australopithecus hoisei and Australopithecus sp. indct. All of these descriptions were rendered obsolete by the appearance in 1991 of Wood s monograph on the entire Koobi Fora assemblage as it had accumulated up to 1981. As far as we are aware, with a single exception, Woods attributions in this work of various Koobi Fora specimens to //. hoisei or (generally in the case ol more fragmentary specimens) to Australopithecus sp. have not been seriously contested. The one exception to such attribution of the Koobi Fora hominids not allocated to Homo is Kimbels (1989) identification of the early KNM-ER 2602 (very) partial cranium as a member of Australopithecus afarensis. However, Wood (1991) prefers to be more cautious and continues to refer this extremely fragmentary specimen to Australopithecus sp. indct. We regret the absence of this specimen Irom the descriptions in this volume, and must refer the reader to Wood (1991: 130-131, Fig. 3-29). 1 lowcver, it may be worth noting that this specimen appears to have a sagittal crest that is rather uniform a/p and continues very far posteriorly without showing signs ol dividing. The bone of the cranium is quite thick, well forward into the preserved parietal region ami the occipital profile is rather smoothly curved without any protiusioii. None of these features is characteristic ol the Ol I ->» KNM-ER 406 or AL 444-2 crania. Molloway (2000) reports the following cranial capacities: KNM-ER 406, 525 ml; ER 407, 510 ml; M 732, 500 ml; ER 13750, 475 ml.

ORA ( E A S T T L R K A N A ,

>l0RPHOLOGV imigcs of Koobi Fora specimens mentioned but not llustrated in this entry can be found in Wood (1991). One Koobi Fora specimen, the ER 405 palate, is a -lose match for the palate of the \ V T 17000 cranium fa>m West Turkana, and has been included in the
EAST R I D O L F )

143

This plane is obscured in side view by the tail, very anteriorly facing, s/i anteriorly angled anterior region ot the zygomatic arch that carries this angled plane along the nasoalveolar clivus to quite close to the alveolar region. The postglabeilar "plane* (represented by the slightly sunken frontal trigon) is somewhat long, as the cranial profile rises very gentlv to the region above the articular fossa before curving rather steeply downwards just as the sagittal crest splits posteriorly. The descending posterior profile flexes posteriorly and up somewhat to the peaked superior nuchal line/crest, below which the nuchal plane (whose upper portion is slightly concave) descends quite steeply to the chunkv mastoid region. Viewed from the front, the face is extremely broad across the forwardly facing and s/i toll zygomas (the L of which is damaged), which emphasizes the ca. 45* slope of the inferior margins of the anterior roots of the zygomatic arches as they converge on the squared-up-looking upper jaw. The superior margin of the zygoma (as better preserved on the R) courses medially more horizontally, but then turns up just below the horizontal midline of the orbit and proceeds to follow the rounded contour of the orbit laterally. Also as seen from the front, each side of the low, broad base of the slightly laterally puffy and tentshaped cranial roof (which bears a moderately thick sagittal crest) arises just lateral to the midline of the orbits. Viewed from above, the supraorbital region is almost smoothly continuous from side to side, bulging slighdy but broadly across the glabellar region and extending laterally well beyond the very severe bilateral postorbital constriction to flow into the anteriorly facing zygomatic regions. The latter turn back strongly (but not acutely) well away from the braincase and gendy arc posteriorly before turning in just anterior to the mastoid regions, which protrude somewhat laterally. The superior nuchal line/crest angles back from each mastoid region and then squares oft the back of the skull. Also from above, the sides of the braincase diverge quite strongly from the very constricted (and thus narrow) anterior portion, reaching their widest expanse at the mastoid regions. In rear profile, the skull is extremely wide across the low puffy mastoid regions and there is a more or less continuous but gentle upward curve of the side walls until quite high up, when they curve in more strongly to turn up almost fully vertically to become the still-separate elevations of the sagittal crest. The posterior roots of the zygomatic arches lie a bit higher, and extend laterally much farther, than the mastoid regions.

144

SITE

ENTRIES

The face is haftcd to the neurocranium far anteriorly, resulting in a very pronounced postorbital constriction and a large exposed postorbital plate. The lateral orbital margins thus extend greatly lateral to the bony contact of the face with the neurocranium, and the supraorbital margins arc essentially laterally projecting struts, relatively thin superoinferiorly and wider anteroposterior!)'. Flat above, in front they curve smoothly around into the orbital roof. The bone in this region is vcrmiculatc. Slightly on the L, and more pronouncedly on the R, there is a supraorbital notch, just lateral to glabella, that takes the form of an indentation in the anterior surface of the "torus." Glabella is bulbous and very broad, roughly in the form of an inverted trapezoid, and projects strongly anteriorly. Its superior surface is shallowly indented. The orbits are matrix-filled and roughly subcircular, with a slight truncation of the inferomedial corner. The lacrimal fossae arc not visible. On the R is preserved a single and relatively small infraorbital foramen that lies well below the inferior margin of the orbit and faces down to open into a deep gutter that runs infcriorly. The intcrorbital region is very broad. The nasomaxillary sutures arc not determinable, but there appears to be a slight rise across the preserved right nasal bone, with a hint of slight midline keeling. There is a hint of flexion of the nasal bones, quite far below nasion. This latter point lies at almost the most prominent point of glabella. As preserved, the nasal aperture is piriform, tall and narrow, but it is impossible to determine how far the nasal bones originally descended. The lower part of the lateral margins of the nasal aperture present a well defined but somewhat blunted edge. The inferior margin of the aperture is also well defined, even in the absence of distinct crests. The inside of the nasal cavity is exposed only anteriorly, where its lateral walls are smooth and curve smoothly into the flat (and not depressed) nasal floor. The vomer is quite stout and runs right to the front of the nasal cavity, but there is no sign of any nasal spines. Incisive fossae are undetectable in the floor of the nasal cavity. The surface of the bone on the lower face is quite weathered, but there is no evidence that facial pillars existed. The nasoalvcolar clivus was originally quite long and angled forward, possibly with a slight curve.

bital rims. As distinct ridges, they run parallel to the anterior surface of the orbital rim to the level of the supraorbital notch, then curve strongly posteriorlv and converge markedly toward the midline, meeting well anterior to bregma. A long, narrow and shallow frontal trigon is thereby defined. On the R temporal line, just lateral to the posterior turn, is a large circular hole in the bone (pathological?). The converging temporal lines create a modesdy thick but not very hio-h sagittal crest, which starts separating once more into very highly rugose temporal lines some distance anterior to lambda. Continuing to diverge inferiorlv, these lines fade out before reaching the lambdoid sutures. The anterior roots of the zygomatic arches take origin quite far above the alveolar margin and rise steeply up and out, without significant curvature. The zygomas themselves face forward and up, with their superior surfaces twisting laterally to face obliquely up and out. The zygomatic arches are bowed laterally and run horizontally. They are robust, but perhaps somewhat less so than would be expected for an individual so massively constructed. The temporal fossa is huge and subcircular, almost as long a/p as it is deep mediolaterally. The anterior wall of the temporal fossa, i.e., the postorbital plate, is oriented obliquely forward, so that the fossa expands conically inferoanteriorly. It is impossible to determine whether there was a distinctly delineated infratemporal fossa. The parietals intrude deeply into a very welldeveloped mastoid notch, which lies far posteriorly. The temporal overlaps considerably on to the parietal, from the sphenotemporal suture all the way back to the notch. A tiny parietomastoid suture runs horizontally from the notch to asterion. Anterior to this the nuchal crest flows smoothly into the lateral angle of the mastoid. Above the region of the parietal notch is a large, low supramastoid swelling that runs into a low but tall suprameatal crest that expands laterally and anteriorly into a sharply flaring posterior root of the zygomatic arch that takes its origin above the anteriorly tilted auditory meatus. The anteropostcriorly very long, laterally flaring and concavely shelflike posterior root of the arch forms the roof of the lateral twothirds of the articular fossa. Forward of its posterior root, the zygomatic arch continues a gentle outward curve before recurving to meet its anterior root.

The temporal lines originate at the zygomaticofrontal sutures, and are continuous below with sharp crests that continue well down onto the zygomas and define the outer margin of the external or-

The articular fossa is very wide mediolaterallv, and is extremely deep and straight although slightly angled forward. It flows smoothly into a very stout and cylindrical articular process anteriorly, and is

KOOBI

FORA

( E A S T TURRANA,

hounded posteriorly by a small and laterally placed re ] cn oid plate as well as by the anterior border of he ectotvmpanic rube. The articular process expands jjjlv into a large swelling (medial articular tuber-le or cntoglenoid process) that closes off the fossa on that side The ectotvmpanic tube is long, slightly hjckwardlv oriented and closely appressed to the mastoid, which extends beneath it. The auditory- meatus is Urge, compressed a/p, tilted forward and formed in thinnish bone. On the R there appears to be preserved the remains of a vaginal process that was medially restricted and lay at the front of the tube. Between the va
EAST

RI'DOLF)

heart-shaped and relatively small. The occipital condyles are anteriorly positioned, tall and somewhat arced, with parallel sides. Posterior condylar foramina lie immediately behind them. The anterior margin of the foramen lies level with the back of the articular fossae. The basiocciput tapers anteriorly, and rises quite sharply. The posterior root of the vomer is extremely broad and indented in the midline to produce two small alae. The posterior choanac arc tall, but quite narrow. The front of the palate is sheared off, but it is evident that the incisors, canines and even P i s were aligned straight across, with the tooth rows running backward only from the latter teeth. Even the buccal root of P2 is still visible from the front. T h e tooth rows arc essentially parallel and very long, and surround a deep, steep-sided palate. There was evidently a fairly sharp anterior slope, but its visible posterior extent is very restricted. The single incisive foramen lies in line with the P i s , and is not very large. There is a very long and stout posterior nasal spine. T h e crowns of all cheek teeth are missing, but it is evident that P2 was massive, and the molars yet more so and buccolingually very broad. It seems that the M l was smaller than either the M 2 or M 3 . KXM-ER 732. Partial cranium with most of L side; nasal cavity structures, nearly all teeth and R zygomatic arch missing. T h e cranial bone is very thin. In R profile, the quite swollen and s/i tall glabellar region protrudes a bit anteriorly, slightly overhanging a very tall, very shallowly concave region that flows into the gently anteriorly arcing plane of the fonvardly facing, s/i anteriorly oriented, anterior root of the zygomatic arch, which then curves down toward the missing alveolar region. T h e postglabellar plane is long and rises slowly to the region above the posterior root of the zygomatic arch, behind which the profile curves more strongly and steeply down toward the missing occipital region. From the front, the R zygoma is quite laterally flaring, suggesting a very broad bizygomatic midface (cf. ER 406). Also as in ER 406, the inferior margin of the anteriorly facing, s/i tall zygoma and the anterior root of the zygomatic arch angles in at ca. 45" toward the rather vertical side of the upper jaw, and the superior margin appears to have curved up and around the orbit laterally. As better preserved on the R, the side of the low frontal, which is somewhat rounded across its top, arises just medial to the lateral margin of the orbit. From before, postorbital constriction (preserved on the R) is somewhat marked and the

r^^^%

146

SITE

posterior orbital plate, which extends quite laterally, faces extensively upon the temporal fossa. As in 406, the supraorbital region would have extended quite laterally and flowed'into the widely arcing zygomatic arch, which terminates as a shelf just in front of the mastoid region. Compared to the larger 406, the side of the braincase widens much more rapidly posteriorly. Seen in rear profile, the braincase was fairly smoothly arced from above the laterally projecting posterior root of the zygomatic arch across the top. The face is hafted to the neurocranium very anteriorly, with pronounced postorbital constriction exposing a broad postorbital plate. The relatively s/i thin and not anteriorly projecting superior orbital margins project laterally beyond the constriction and are vertically thicker medially, tapering laterally. These margins are confluent with a broad and somewhat bulbous and anteriorly projecting glabella, and beneath they curve smoothly into the orbital roof. The superior surface of glabella is confluent with a slightly sunken surface just behind it and lying between the temporal lines. The frontal arcs back gradually behind this surface, the braincase reaching its maximum height well posterior to bregma. Beyond this point it seems that the missing rear of the skull probably curved quite tightly down to the preserved mastoid region. Frontal sinuses were probably rather small and confined to the glabellar region, as demonstrated by the broken left torus and the thinness of the cranial bone behind glabella. As preserved on the R, the temporal line emerges from the lateral margin of the orbit, and curves back at a point lateral to the midline of the orbit. The bone surface is highly weathered, but the orientation of the lines anteriorly suggests that they did not converge. The L medial orbital wall is crushed, and the R is obscured by matrix. However, it is evident that the intcrorbital distance was broad. As preserved on the R, the orbits were subcircular, and the lacrimal fossa, bounded by a sharp anterior and a very small posterior crest, was positioned far down and laterally within the inferior orbital margin (right above the 'double and smallish infraorbital foramina that arc positioned quite tar below the orbit, face downwards, and open into distinct gutters that extend interiorly). Nasion is preserved, and below it are the superior extremities of both nasal bones. These elements arc narrow at the frontonasal suture (approx. 6 mm across both), and become even narrower (to less than 3 mm across both) as they proceed interiorly between the very broad

ENTRIES

frontal processes of the maxilla. As narrow as they ar the nasals come together in a thin low keel along th* nasonasal suture. The relatively flat and forwardly facing anterior root of the zygomatic arch originates quite far above the alveolar margin, and its inferior edge runs obliquely up and out. Nothing of the margins of the nasal aperture or of the nasoalveolar clivus is preserved; it is evident, however, that the preserved RPl must have been far forward and transversely in line with the Is and Cs. The superior surface of the posterior root of the zygomatic arch is very long and concavely broad, and forms the roof of at least the lateral half of the articular fossa. A distinct if low postglenoid plate lies at the back of a very wide and deep articular fossa that was bounded anteriorly by a tall, cylindrical articular eminence. This eminence flexes posteriorly at its medial extremity to close off the articular fossa medially. The ectotympanic tube is missing, but it was long and obliquely oriented. It would have been closely appressed to the base of the mastoid, but would not have been enveloped by that structure as is the case in 406. The mastoid region was quite inflated, extending as in 406 well below the level of the now-missing ectotympanic tube inferiorly. It was wide and had a slope to its posterior surface, but shows no sign of being distended into a process. The medial preserved portion of the mastoid appears to extend to the occipitomastoid suture. There is no elevation at this point, nor is there anv si^n of a mastoid notch laterally. Pneumatization extended above the mastoid portion to invade the squamous portion above in the region ot the swollen supramastoid eminence, from which the mastoid is separated by a tall but shallow sulcus. There is an oblique parietal notch in the superior portion of the supramastoid region, into which the interior extremity' of the parietal fits. The supramastoid bulge flows into a prominent suprameatal crest, which in turn is confluent with the laterally expanded posterior root of the zygomatic arch. The orientation of the posterior and anterior roots of the zygomatic arch indicate that the arch itself would have arced out laterally. Even though the alisphenoid is missing, it is clear that the temporal fossa would have been wide as well as long. The oblique orientation of the postorbital plate indicates that the temporal fossa would have enlarged anterointeriorly. The surface of the temporal anterior to the articular eminence slopes up considerably, and

Room

FORA

( E A S T TURKANA,

medially forms a sharp angle with the squamosal portion. The petrosal is broken medially, and externally is mo eroded for determination of its features. Internally, the superior surface of the petrosal is relatively flat and broad, with a slight trace posteriorly of a superior petrous sinus. There is no evidence of a subarcuate fossa. The surface below is damaged, so that it is impossible to determine if a fossa existed in association with the inferior semicircular canal. T h e carotid foramen is quite large and faces back and medially. The exit of the sigmoid sinus via the jugular foramen lies quite far posterior to it. A groove that plausibly housed the posterior division of the middle meningeal arterv lies at the juncture between the squamosal and petrosal portions of the temporal. Anteriorly in the cranial cavity, the frontal lobes would have lain over onlv the medial half of the orbital cone. There was apparently virtually no frontal crest, and the cribriform plate would have lain far posteriorly. Both P I and P2 were three-rooted; these roots were long, and the two alveoli of P I visible from in front lay far forward in the jaw. Only part of the large P2 crown is preserved. It bears a large metacone from which a thick postcingulum runs around a very deep posterior fovea. No M crowns are preserved, but it appears from what remains of the roots that the crowns were relatively large for this rather small individual, and quite wide buccolingually. A t least on M 1 - M 2 , the long roots were also quite splayed b/1. KNM-ER )3750. Partial cranial vault and upper face, lacking most of the L side of the neurocranium and all of the basicranium, lower face and nasal structures. Minimally reconstructed; very similar to ER 406, if perhaps a little more lightly built. T h e cranial bone is extraordinarily thin. The orbits are incomplete, but were probably wider than tall, with a smoothly curved lateral margin. The fragment of bone that currently descends from glabella may be the nasal bones, but if so these are facing backwards. Very pronounced postorbital constriction, leaving the supraorbital areas projecting far laterally, as in 406. Supraorbital margins are of uniform thickness, but are not very tall s/i and curve sharply but smoothly into the roof of the orbit. T h e frontal lobes would have covered only the posterior half of the orbital cones. Glabella is broad, and stands a little in tront of the retreating orbital margins. Although the skull is weathered, the temporal lines clearly run up

,yr,T

EAST

RUDOLF)

147

the lateral margin of the frontal process of the zygoma to continue over the orbital region, forming the posterior edge of the superior orbital rim. From about the midpoint of the orbit (as seen on the R) the temporal lines curve posteriorly to converge well anterior to where bregma would have been, thus delineating a very shallow frontal trigon. A low sagittal crest rose from the point of convergence to peak posterior to bregma, fading out again by lambda. From the slightly depressed frontal trigon the cranial profile rises gradually to a point past bregma, whence it curves rather more steeply into the more vertical occipital plane. A fairly well-delineated and ridgelike nuchal line forms a sharply inwardly angled boundary between the occipital plane and the broad and rugose nuchal plane. Toward the midline the nuchal lines descend bilaterally, peaking at the midline itself. At the intersection of the nuchal lines and the midline this peak impresses itself on a small but prominent bony swelling. T h e lambdoid sutures rise sharply upward from asterion to a point well lateral to lambda, at which point they run more or less horizontally to meet at that point. Lambda is thus low, and the occipital plane is very broad compared to its height. Below the horizontal portions of the lambdoid sutures, the bone bulges slightly. T h e mastoid regions are missing from the reconstruction, but the contour of the surrounding bone and an unattached but associated fragment from the posterior surface of the left mastoid indicates a low, oblique and rugose posterior surface, and pneumatization interiorly with small but not tiny air cells. As seen on the R, there was a broad, shallow digastric depression medial to this area, at the lateral extremity7 of the nuchal plane. T h e squamosal portion of the temporal extended far back, terminating in an obliquely oriented parietal notch, lying well above the mastoid region. There was at least some lateral mastoid bulge, separated by a sulcus from a more superoantcriorly situated low eminence that flowed forward and down into a more distinctly crcstlike suprameatal region, which in turn flowed into the laterally expanding, shclflike and extremely broad posterior root of the zygomatic arch, preserved on the R side. This structure roofed at least the lateral one-half of the articular fossa. T h e fossa itself is very deep, and is bounded anteriorly by a very deep and stout articular eminence with a lunate coronal profile. This eminence expands into a massive eminence medially (i.e., medial articular tubercle, or cntoglenoid tubercle), which would have largely closed off the articular

K

148

SITE

fossa on this side. The orientation or the fossa is obliquely forward; the cctotympanic area posterior to it is missing. The superior surface of the posterior root of the zygomatic arch is concave, and Hows up into the superior margin of the zygomatic arch itself. This structure descends obliquely forward to meet the anterolateral!)' and slightly upward-facing body of the zygoma. The maximum bizygomatie width appears to have been quite far back along the outwardly bowed arch, rather than at its midpoint. The temporal fossa was quite deep, and expanded anteriorly and interiorly behind the obliquely oriented zygoma. As in 406, on the front of the squamous there is a distinct vertical crest. This, however, represents a muscle-marking on the bone, rather than a point of flexure of the bone itself. O H 5 Cranial Morph (includes KNiM-ER 23000) KXM-ER 23000. Nearly all of a frontal, R temporal and most ot an occipital plane. Largely cracked and reconstructed. From the front, the s/i tall supraorbital margins arc gently ni/1 over the orbits, with a very slight lateral taper. They are confluent across a very broad and somewhat flat glabellar region that is slightly concave superiorly. It appears that the orbits were tall and narrowly ovoid, with somewhat straight medial sides, and the orbital roofs were slightly concave and make a blunt corner onto the rounded supraorbital surface above. In profile the glabellar region is fairly vertical, and neither it nor the supraorbital margins protrudes anteriorly or superiorly. The frontonasal suture is preserved, and lies fairly low on the interorbital region. Its lateralmost extent is contained well medial to the medial orbital margins. From the side, there is a long posrtoral plane, behind which there is a gentle rise to the ven- posteriorly located bregma. The temporal lines delineate the posterior margin of the a/p long supraorbital surfaces, and converge rapidly to the midline, to form a single but not ven' high-rising sagittal crest. From above, there is marked postorbital constriction, with the supraorbital region extending well lateral to the posterior rise of the frontal and forming a more or less vertical surface that faces on to the temporal fossa. T h e bone along the undifferentiated coronal suture is quite thick. The partial R temporal preserves enough of the squamosal region to indicate that its suture was long and low, and not very high. The narrow and

ENTRIES

somewhat medially inclined parietal notch 1" posteriorly, behind the region of the compress^ ** obliquely oriented auditory meatus and above th ^ short, moderately swollen and laterally flatten d ° ^ toid region. The posterior root of the zygonJtic^t emerges smoothly from above the midpoint of th ditory meatus, and expands laterally to form a ° *"" nent shelf above the a/p long and somewhat conT" articular fossa. The zygomatic arch decreases i n ^ height toward the region of the articular fossa b ' then increases again anterior to it as its lateral surfaT becomes more vertical in orientation. The posterior part of the temporal fossa is quite constricted medially, just in front of the only moderately broad shelf formed by the posterior root of the zygomatic arch. From above, the bone of the squamosal and petromastoid sutures is extremely thick, and the superior surface of the petrosal is quite broad ni/1 and flat, lacking any trace of the superior semicircular canal. Also, the foramen spinosum is completely contained within the petrosal (indeed lies quite posteriorly); and from it runs a well-defined groove for the posterior branch of the posterior meningeal artery, which quickly bifurcates into gently anteriorly coursing and strongly posteriorly directed branches. T h e groove for the superior petrous sinus is quite broad and well defined, and extends from just above the internal acoustic meatus to the posterior limit of the petrosal. The subarcuate fossa is large and patent, and lies well below the groove for the sinus and well behind the internal auditor)' meatus. The tip of the petrosal is damaged, but it is clear that the portion anterior to the meatus was not ven' long. There is no visible groove for the superior sigmoid sinus. From the side, the preserved region of the occipitomastoid suture is ven' thick a/p and shows indications of shallow denticulation. From the rear, a corrugated superior nuchal line runs up, out and around the low mastoid region, to turn medially toward a notch low down on the occipitomastoid suture. This muscle scarring delineates a posteriorly and somewhat obliquely facing surface of the mastoid region. As better seen on the R, this surface continues right on to the occiput. The roundedly triangular pre served portion of the partial occipital is ven' broad asterionicallv. The occipital plane is very short a broad and ven- shallowly arcs across the region lambda. The thick lambdoid suture is V^f™ exposed on the R. Evenly but moderately denncu^, this suture faces obliquely anteriorly, thus resemble

KOOBI FORA ( E A S T TURKANA, EAST

the squamosal suture in form. Just below the lambAold suture the mastoid region bulges abruptly laterally. The distinction between the narrower upper and wider lower portions of the occipital is delineated internally by the straight but upwardly slanted grooves for the transverse sinuses, of which the L is more dceplv impressed than the R. The impressions of the cerebellar lobes are shallow and subequal in size, and thev are large relative to the impressions of the occipital lobes. On the R there is a trace of a groove for an accessory sinus curving down and slighdy laterally from well below the damaged region of the internal occipital protuberance (as in O H 5). KNM-ER 729A Mandibular/Lower Dental Morph (includes ER 810A and B, 1806A, B, C and D). KNM-ER 729A. Large mandible lacking L ramus and top of R ramus; extensively restored. Lateral Is, RP1, LM1 and most of canine crowns are missing. LP1 and RM3 are the least worn and weathered of the preserved teeth. From underneath, the jaw is weakly "bell shaped," with a slight keel down the midline of the symphysis externally, ending in a very slight bulge at the bottom. Thus, seen from the side, the symphysis arcs out slighdy in a smooth curve and there is also a smooth curve across the symphysis from side to side. T h e corpus is deep and robust, posterior to M 2 thinning out somewhat on its inferior margin. The mental foramen is preserved on L below P 1 - P 2 . The ramus obscures most of M3 in side view. The mandibular foramen is compressed and oriented up and back, and lacked a lingula. Also as seen on the R side, the mylohyoid line is very faint, there is no real mandibular fossa, and it appears that the digastric fossae, as represented by low ridges on the underside of the corpus, were positioned quite posteriorly. The genial region is damaged, but it appears that there was a large, single genial fossa. There is some rugosity externally on the rather straight and noninflected gonial angle. T h e dental arcade is of diverging U-shape with a slight curve at the front, the Cs being positioned a litde aft of the Is. T h e cheek-tooth rows diverge from behind the canine, i.e., the P i is not forwardly positioned. The tooth crowns are all heavily worn and eroded, and there is also some enamel missing on most of them. The I I crowns are narrow and almost parallelsided; judging from the L, the C crowns were narrow, recurved buccally and lingually bear a pillar. In front

RUDOLF)

149

of the pillar is a small anterior fovea, with a longer posterior fovea behind. The Cs are positioned in the jaw in such a way that the Pis contact their d/l corners. The large PI and the much larger P2 are rather straight-sided teeth, both with a very thick postcingulid that goes around from the metaconid to the protoconid, and that encloses a narrow but quite deep basin. As seen on the P2, a short deep groove separates the metaconid from the protoconid. PI bears a small anterior fovea, but no groove is visible. Both Ps arc basically similar: subsquarish, but with an oblique axis running from the distended d/l corner on the postcingulid to the m/b-distended protoconid. However, P2 is substantially larger in all dimensions. M l is noticeably smaller than M2 and M 3 . All Ms were wrinkled to some extent, but were most so on M 3 . The posterior moiety of all Ms is enlarged and dominated by a centrally placed and cuspulatcd hypoconulid that occupies the entire rear of the tooth; the other four anterior cusps (arranged in b/1 pairs) are thus very mesially placed. As best seen on the RM3, the metaconid is quite large m/d and b/1 compared to the m/d truncated protoconid, and the m/d elongate horizontally crenulated hypoconid and entoconid regions abut along the midline of the crown. Even though the Ms are b/1 very wide, they are also m/d long; all of them except possibly the M l are longer than wide. KNM-ER 8J0A. Fragmentary mandible missing the R side, much of the symphysis and all tooth crowns. However, to judge from its roots M l was noticeably smaller than M 2 and M 3 . KNM-ER 810B. Lower L M crown that does not fit well on any exposed roots and has a differently shaped pulp cavity. Morphologically, however, it compares well with its counterpart in 729 (e.g., it is very wide b/1, the hypoconid extends across midline, and a centrally placed hypoconulid dominates the posterior part of the tooth). KNM-ER 1S06. Anterior {A and B) and posterior (C and D) parts of R and L corpora. All tooth crowns arc missing, but what is preserved is comparable to ER729. K N M - E R 1820 Lower Dental Morph (possibly includes ER 3230,15390) KNM-ER 1820. Part of a L juvenile mandibular corpus with crown of LI2 embedded in the bone, the

&&\\m Hstlonal d'!iis(o!re Nn uApttrlemthit eta Prohistc 1, ruo fluno Panb«ro!

150

SITE

roots of dml, the erupted and slightly worn crown of dm2, and the erupting and slightly damaged crown of

Ml. The root of LI2 had begun to develop, and the incisaJ edge bore three well-defined mamclons. The dm2 is relatively very m/d elongate and b/1 narrow, tapering both fore and aft (though it is straightcr across the front and more tightly rounded distally), with broad cusp bases that effectively fill in the central basin and very tall, pointed cusps. The fronts of the larger protoconid and m/d slightly longer mctaconid are about level with one another; an extremely m/d thick paracristid, with only a trace of a fovea, courses low down in front of their bases. The moderate hypoconid (which extends only slightly lingually beyond the midline of the crown) extends a bit more mcsially than the smaller and m/d compressed entoconid opposite it. The hypoconulid is large and very buccally placed, with its base oriented lingually to touch the entoconid; lingual and distal to the hypoconulid is a small cuspulid and mesial to it is a small but deep fovea. M l is also a relatively m/d long, moderately b/I narrow and mesially and distally tapering tooth, with some thick wrinkling of its enamel; all of its cusps are very tall and pointed. The protoconid and hypoconid are larger b/1 than their more compressed but m/d longer and more distally situated lingual counterparts. The base of the bluntly wedgeshaped hypoconid extends across the midline of the crown to make a moderate contact with the metaconid and a smaller one with the entoconid. The wedge-shaped hypoconulid is relatively large and very buccally placed, its base making contact only with the entoconid; d/1 to it is a large secondary cusp lying just lingual to the midline of the crown. There is a moderately sized, relatively deep and m/1 oriented anterior fovea or trigonid basin that is enclosed in front by a fairly thick paracristid that courses between the apices of the protoconid and metaconid. Behind, another crest runs between these cusp apices. All cusp apices are somewhat internally shifted, producing sloping sides and a relatively compressed internal basin. KNM-ER 3230. Reconstructed mandibular corpus with all teeth, lacking both rami. Inferior profile is bell-shaped, the inferior margin peaking slightly at the base of the front of the symphysis. Otherwise the symphysis is more or less flat across, without adornment. Corpus thickens dramatically at the level of M l , notably through the addition

ENTRIES

of bone on its external surface. On the R the rise f the ramus can just be discerned, indicating that th ramus would have in side view covered the whole f M3. Mental foramina arc large bilaterally, and lie under PI, i.e., very far forward in the mandible.The anterior teeth arc set in a very shallow anterior curve and the straight tooth rows diverge posteriorly from' behind the canines. All teeth but M3 are moderately worn. The I roots arc quite long and backwardly curving. The straight-sided II crowns arc smaller than the more laterally flaring I2s, but all arc small. The C roots arc longer than the I roots but also curve backwards* the small crowns arc slender and triangular in profile. A low but broad central pillar on the lingual surface delineates a narrow anterior fovea from a broader posterior fovea. The check teeth are massive. The moderate-sized PI and significantly m/d and b/1 larger P2 are similar in having mcsially displaced metaconids and protoconids that lie opposite to one another, with a stout and thick postcingulid running from the lingual aspect of the metaconid around the back of the tooth to the distal side of the protoconid, where it terminates in a thickening not quite level with the buccal side of the crown. This postcingulid encloses a very tiny but deep fovea. There is no evidence on either tooth of an anterior fovea. P2, at least, had three roots. M l appears small relative to P2 (which is actually b/1 wider) and is markedly smaller m/d and especially b/1 than the long, moderately narrow and subequally sized M 2 - M 3 . There may have been some crenulation on M l and M2, but this is more pronounced on M3. In all Ms the buccal and slightly b/1 smaller but m/d longer lingual cusps lie directly opposite one another. The M cusps are placed peripherally, producing rather straight-sided teeth, and are wide and narrow, severely constricting the talonid basins. Each M also has a well-defined though m/d narrow trigonid basin that is bounded mesially by a thick paracristid that courses straight across the front of the tooth from the middle of the metaconid to the middle of protoconid. In all Ms the bluntly wedge-shaped hypoconid extends across the midline, primarily contacting the entoconid; and each has a large, buccally placed hypoconulid, with a low, d/1-oricntcd (and on M 2 - M 3 d/1-distcndcd) ledgclikc structure between it and the entoconid. It is difficult to be certain given the amount of wear on the only comparable tooth, the M l , but it

v-KOOHI

FOKA ( E A S T TUKKANA, E A S T

seems quite likely that 3230 and 1820 represent the same dental morph. It seems reasonable to assume that interstitial wear (which is quite evident) shortened the Ml of 3230 and straightened up its mesial and distal sides. And the disposition of its cusps (e.g., the almost buccally aligned protoconid, hypoconid, and relatively large hypoconulid, the just-lingual-to-the-midline position of the cuspulid between the latter cusp and the cntoconid, the m/d elongate lingual cusps, the evidence of a small metastylid and the long, justIingual-to-thc-midlinc position of the talonid basin) is remarkably similar to what is seen in the unworn M l of 1820. KNM-ER 15930. L mandibular corpus fragment with M 1 - M 3 and enamellcss crown of P2. Tooth rows are divergent and run straight until the level of M 3 , where they flex buccally. Even though the crown of P2 is missing its enamel, what remains of the outline at the neck shows that this tooth would have been b/1 wider than the molar behind it, with a clear lingual distension; further, it would have been substantially smaller than the molars behind (as in the massive mandible 3230). M l is very worn and M 2 somewhat worn; M3 is barely worn, showing very tall, pointed cusps. M l is small compared to the M2 behind it. M2 and M3 are similar in having internally placed lingual and buccal cusp apices; thus both sides of these teeth are somewhat bulbous, and the talonid basin is squeezed to a mere crevice. The M2 is generally similar to those of 3230, and appears to have a large, buccally shifted hypoconulid with a small cuspulid lingual to it. On M3 the size relationship of these structures is reversed, with a larger cusp in the midline and a smaller one buccally. M3 has a very deep anterior fovea (as in the M2 of 1820), and somewhat internally placed cusp apices, both lingually and buccally. It also has tall cusps separated from one another by deep crevices, and its crown is somewhat bulbous both buccally and lingually, the talonid basin being reduced to a crevice running down the midline of the tooth. Unassignable to Morph KNM-ER 370E. Maxillary uninformative.

fragment,

rather

KNM-ER 370E Probable upper LC with robust long root and totally worn-down crown. KNM-EH 370G. Unidentifiable worn-down crown, probably from an anterior tooth.

RUDOLF)

151

KNM-ER 370H. Uninformative cranial fragment. KNM-ER I477A. Juvenile mandibular corpus lacking rami, all dis, and half of Rdc. Some damage near symphysis, as well as to Ldml and dm2. In the jaw arc the somewhat worn and/or broken R and Ldcs, dm Is and dm2s, and complete M l crowns in crypts. Also associated arc the uncrupted crowns of LI1 (1477B), LC {1477Q and LP2 (1477D). The symphysis remains partly unfuscd inferiorly on its internal surface, below the double genial pits (compared to anthropoids in general this developmental state is odd, given this juvenile's relatively advanced stage of dental eruption). In the front of the receding symphysis there is a trace of a midline keel, but otherwise this region is unremarkable. The plane above the genial pits is long and sloping, rather than narrower and more vertical. On both sides traces of the crypt for M2 are preserved; on the right side, especially, this crypt is quite large, suggesting that the crown was both large and fairly well formed. As preserved on the L, the dc crown had a longer distal than mesial slope. Lingually it bears a short anterior fovea and a longer and shallower posterior fovea. The dm Is have dentine exposed on all cusps, which are bulbous (especially the hypoconid) and well-defined. The trigonid is narrower b/1 than the talonid, and a fairly stout paracristid runs from in front of the protoconid down and d/1 to the base of the metaconid, enclosing a short but deep basin. The bases of the protoconid and metaconid are melded in the midline. The paracristid thins toward the metaconid, leaving the protoconid more mesially projecting. Interestingly, the protoconid is not remarkably exodacnodont. The apices of the subscqual hypoconid (whose base extends a bit across the midline of the crown to contact the entoconid) and cntoconid are somewhat peripheral and separated from each other, with a medium-sized and slightly buccally shifted hypoconulid intruding a bit between their bases distally. There is a small shelf between the hypoconulid and the entoconid. The dm2s are also m/d long and relatively narrow b/1, with well-defined and bulbous cusps. Both arc markedly larger than the dm Is both b/1 and m/d. As seen on the R, the dm2 has a short, thick paracristid that is more mesially projecting near the metaconid, which is somewhat more mesially projecting than the protoconid; the bases of the metaconid and the protoconid are melded in the midline. The hypoconid (whose base extends slightly across the

*& *«?

152

SITE

midline of the tooth to make small contacts with the mctaconid and entoconid) lies slightly mesial to the more b/1 compressed and m/d elongate entoconid. As on d m l , the hypoconulid on dm2 is large and buccally shifted, but it is also somewhat m/d compressed and obliquely oriented to touch the base of the entoconid; a small cuspulated shelf courses from it to behind the entoconid. Also on dm2, the buccal cusps are more bulbous at their sides, while the lingual ones are straightcr-sided. The dm Is and dm2s arc unique among specimens attributed to a hominid taxon. As can be seen within the crypt, the All protoconid and somewhat m/d longer metaconid are opposite one another, and in front of them lies a well-developed basin surrounded in front by a thin paracristid. The fairly large, bluntly wedge-shaped Irypoconid extends lingually well beyond the midline to contact the somewhat m/d compressed entoconid. The base of the relatively large, buccally shifted and wedge-shaped hypoconulid primarily contacts the Irypoconid. Lingual to the hypoconulid is a medium-sized, deep fovea. T h e enamel is smooth, not crenulated. Among the dug-out permanent teeth, the I I crown is not quite formed to its neck but is relatively straight-sided, although a bit more rounded distally. T h e incisal edge bears three blunt mamelons and the lingual surface curves smoothly out to the neck. T h e L C crown is formed to just above the lingual swelling. Its mesial edge is noticeably shorter than the distal edge; thus, there is a shorter anterior than posterior fovea, both foveae being shallow and poorly defined. T h e LP2 crown already curves in below, but is incompletely formed. T h e very mesially placed metaconid is somewhat smaller than the protoconid, and is more internally placed. A crisp paracristid runs between the apices of these cusps, enclosing a moderately long and deep basin. A stout postcingulid emanates from the distal side of the protoconid, which bears a small stylid-like peak just distal to the protoconid. This crest encloses a relatively well-developed talonid basin as it runs to terminate on the lingual side of the metaconid in a small stylid-like peak. There is something of an oblique orientation to this tooth. KNM-ER 1482a. Damaged L corpus that continues around the symphysis to the R M 1 . It is quite narrow at the front and the tooth rows are strongly divergent. T h e bone of the corpus is thick right to the bottom. T h e prcsen'ed P2s are very strange, with slightly twinned protoconids, and are wider lingually than

K N TRIE S

buccally (the reverse of the typical configuration^ v, metaconid extends into the area otherwise oc the anterior fovea. A very thick postcingulid CUpiCdb>' from the metaconid by a deep crease s w i n ^ * ^ the back of the tooth, enclosing a ^ m a / L T ^ fovea. The molars, although quite heavily j ' 1 0 7 would have been wide b/1 and rather rounded T l f ^ hypoconid extends wry far across the midline' \\ -c not all of the M 3 would have been obscured frornT c side by the rising ramus. KNM-ER 15940. L and R probable lower M2 crowns. Moderately worn, preserving fairly de S o v u l a t i o n s . Both are subovoid in occlusal outlinT with somewhat compressed and peripherally p h cc d cusps that are semi-incorporated into a cresting system that is most continuous across the front of the tooth O n both, the trigonid basin is quite long m/d and enclosed mesially by a very arcuate paracristid that runs between the metaconid and protoconid. These two cusps are subequal in size and lie opposite one another, their bases meeting in the crown midline. The base of the fairly large hypoconulid is fairly long m/d and squared-up. It does not extend far across the midline of the tooth before abutting the base of the fairly m/d long entoconid. The hypoconulid is small and somewhat buccally shifted; its narrow base extends along the side of the hypoconid and makes a small contact with the entoconid. A fairly b/1 wide shelf extends between the hypoconulid and the entoconid.

REFERENCES Brown, F. and C. Feibel. 1986. Revision of lithostrangraphic nomenclature in the Koobi Fora region, Kenya./ Geo!. Soc. London 143:297-310. Brown, F. et al. 1985. An integrated Pleistocene chronology for the Turkana Basin. In: E. Delson ed, Ancestors: The Hard Evidence. New York: Alan K. Liss, pp. 82-90. Bunn, H. 1986. Patterns of skeletal representation an^ho" minid subsistence activities at Olduvai Gorge Tanzania, and Koobi Fora, Kenya./. Hum. Evot. 1* 6 / J - W Bunn, H. et al. 1980. Fxjj50: an early Pleistocene «tc u. Kenya. WorldArchaeol. 12:109-136. Dav, M. H. et al. 1976. New hominids from EastTurUna,

Kenya.^/P^^-M^;f^ 4 j j Feibel, C. , F. H. Brown and I. McDougalL 1 9 £ graphic context of fossil hominids from the Um

^

KOOBI

FOUA ( E A S T TURKANA, EAST

deposits: Northern Turkana Basin, Kenya, and Ethiopia. Am. J. Phys. Anthropol 78:595-622. Holloway, R. 2000. Brain. In: E. Delson ct al. (eds), Encyclopedia of Human Evolution and Prehistory. New York: Garland Publishing, pp. 141-149. Isaac, G. et al. 1971. Archaeological traces of early hominid activities, east of Lake Rudolf, Kenya. Science 173: 245-248. Kimbel, W. H. 1988. Identification of a partial cranium of Australopithecus afarensis from the Koobi Fora Formation, Kenya./. Hum. Evol 17:647-656. Leakey, R. 1972. Further evidence of Lower Pleistocene hominids from East Rudolf, North Kenya, 1971. Nature 237:264-269. Leakey, R. 1973. Evidence for an advanced Plio-Pleistoccne hominid from East Rudolf, Kenya. Nature 242: 447-450. Leakey, R. 1974. Further evidence of Lower Pleistocene hominids from East Rudolf, North Kenya, 1973. Nature 248:653-656.

RUDOLF)

153

Leakey, R. and A, C. Walker. 1973. New australopithecines from East Rudolf, Kenya (111). Am. J. Phys. Anthropol 39: 205-222. Leakey, R. and A. C. Walker. 1988. New Australopithecus boisei specimens from East and West Lake Turkana, Kenya.. Am. J. Phys. AnthropoL 76:1-24, Lcwin, R. 1987. Bones of Contention. New York: Simon and Schuster. Schick, K. and N. Toth. 1994. Early stone age technology in Africa. In: R. Corrucciru and R. Ciochon (eds). Integrate Paths to the Past. Englewood Cliffs, NJ: Prentice Hall, pp. 429-449. Tattcrsall, 1.1995. The Fossil Trail. New York: Oxford University Press. Wood, B. 1991. Koobi Fora Research Project, Vol. 4: Hominid Cranial Remains. Oxford: Clarendon Press, Repository National Museums of Kenya, PO Box 40658, Nairobi, Kenya.

SITE

154

ENTRIES

^t9 K ! g5| ^^BVJ*S& H^gE |ft,fmijjj H A S EJTT*? V G l f

'•

>>48Bt3tj&l

[3S A* 9fJ^ ^ F V I F ^ B S ^ ^ M L J ^ ij^^^BPWtv >^&ifK H-J> V&^£tt>Zj?"^!23Mf91 ^_J

m

K > **JB|fl B T - S^ -y W I T I ™ J M B H U ^ ^ T ^ P • / MT v9Kp ^JKPWWT^I

^ V J W A J I

/JJJKE} ^jfMk ->W*£S«2afl 1 iff*^ " M M f f l M ^ ^

wBjjpH^^^HRijL

^•Wg^rlf?*! •w^23? HKL *», JVL^

^yfe^^S 1

VBP!\ j.^jvl

v'•'c**''*'* v'*"Bfc^W^S Kk&Sfcs!! •t l-v^/^^y> j £§&

§EHS ijnH

Ia j M^j W M^g S^S K^m J S^• MIT f rJr ' i ' H:3

KOOBI F O R A

Figure 1. KNM-ER 405, partial palate (scales = 1 cm).

KOOBJ FOR A (EAST TTOKANA, EAST

KOOBI FORA

RUDOLF)

Figure 2. KNM-ER 406, cranium (scales = 1 cm).

155

t&

SITE

KOGBS FQWA

USTTRTE-S

FikoseZ.

' # £*A v -"* 1

r

ff,/r

KOOBI PORA ( E A S T TURKANA, EAST RUDOLF)

KOOBI FORA

Figure 4. KNM-ER 732, partial cranium («ale» - 1 cm),

157

Sett ESOTWM

15®

K

ta&

!*i»

KOOBI FORA

Figure 4.

(Continued).

Ko OBI FORA ( E A S T TURKAKA, E A S T R U D O L F )

Figure 5. KNM-ER 733a, partial R mandibular corpus (scale = 1 cm). KOOBI FORA

159

Figure 6. KNM-ER 1477a, partial juvenile mandible (scale = 1 cm).

KOOBI FORA

160

SITE

ENTRIES

Figure 7. L: KNM-ER 1477d, lower LP2; Center and R: KNM-ER 15940, L and R lower molars. Not to scale. KOOBI FORA

Figure 8. KNM-ER 1820, partial juvenile L mandibular corpus (scale = 1 cm). KOOBI FORA

m K O O B I FORA ( E A S T TURKANA, E A S T R U D O L F )

KOOBI FORA

Figure 9. KNM-ER 3230, reconstructed mandibular corpus (scales - 1 cm).

161

162

SITE

ENTRIES

Figure 10. KNM-ER 15930, partial L mandibular corpus (scale = 1 cm). KOOBI FORA

KOOBI FORA

Figure 11. KNM-ER 23000, frontal, temporals and parietals (scales

1 cm).

KOOBI

FORA

( E A S T TURKANA,

KOOBI FORA

Figure 11.

EAST

RUDOLF)

(Continued).

163

164

SITE

KOOBIFORA

ENTRIES

Figure 11.

(Continued).

Koosr

FOR A

t EAST

KOOBIFORA

TCRKAJSTA., E A S T

Figure 11.

Rrooir)

(Continued).

Figure 12. KNM-ER 25520> partial R mandibular corpus (scale = 1 cm). KOOBI FORA

165

KROMDRAAI

Thackeray (1997) report that the Kromdraai A faunal remains probably at least in part represent a carnivore accumulation, while Kromdraai B might have been a natural trap. Faunal dating suggests that the Kromdraai B hominids are penecontemporaneous with Bed I at Olduvai Gorge (McKee, Thackeray and Berger, 1995), suggesting an age of about 1.9-1.75 Ma, while the Kromdraai A deposits are generally thought to be a little younger. Such findings agree generally with the earlier faunal conclusions of Vrba (1975, 1976; Vrba and Panagos, 1982). Recent dating attempts using ESR, U-series and paleomagnetism have yet to yield results.

LOCATION Twin brecciated canty-fill sites (Kromdraai A, the "faunal site," and Kromdraai B, the "hominid site"), Blaauwbank river valley, some 10 km N of Krugersdorp, Gauteng, South Africa (Map 4). DISCOVERY A schoolboy, G. Terblanche, discovered several of the teeth of the first Kromdraai hominid (TM 1517) in June 1938, and much of the rest of the skull was found by R. Broom shortly thereafter. Subsequent work at the site bv Broom led to the discovery of another hominid specimen in 1941, and excavations directed by C. K. Brain (in the mid-1950s), E. Vrba (in the late 1970s) and by others at the Transvaal Museum (in the mid-latel990s) completed the roster of hominids currendy known from the site.

ARCHAEOLOGICAL CONTEXT The first possible artifacts were recovered from Kromdraai B by Brain (1958), and excavations over the past decade have produced artifacts from both Kromdraai A and B (Kuman, Field and Thackeray, 1997). Kromdraai A artifacts are mosdy Oldowan in aspect, though there are a couple of largeflakessuggesting Developed Oldowan to Early Acheulean affinities (Kuman, Field and Thackeray, 1997); Kromdraai B artifacts are few and crude. More than one hominid was on the Transvaal landscape during the time of accumulation of the Kromdraai fossils, and it is impossible to make a firm association between hominids and artifacts.

MATERIAL Twenty-nine individually numbered adult and juvenile fossils, mosdy fragmentary crania, isolated teeth, or postcranial bones, are listed by Thackeray et al. (2001), who estimate that they represent a minimum of nine individuals. Most complete specimen is the partial skull T M 1517a (but see below). DATING AND STRATIGRAPHIC CONTEXT Partridge (1982) divided the hominid-vielding Kromdraai B deposits into five members, all hominid fossils coming from Member B. Kuman, Field and

PREVIOUS DESCRIPTIONS AND ANALYSES Kromdraai B was the first locality to produce evidence of "robust" australopiths, and Broom (193S) proposed

166

KROMDRAAI

the new genus and species Paranthropus robustus to contain the partial cranium and mandible T M 1517a and b. Later this author added to the hypodigm of this species an incomplete juvenile mandible found in adjacent deposits (Broom, 1946), and Grinc (1982a,b) has described further juvenile hominids from Kromdraai. Since Brooms original description, nobody has questioned either the unity or the specific distinctiveness of the Kromdraai hominids (though Wolpoff, e.g., 1973, came close to the latter); the only rational dispute has been over whether the species robustus should be assigned to Paranthropus or to the genus Australopithecus, already described from Taung by Dart in 1925. For most of the second half of the twentieth century, despite the valiant efforts of those such as Robinson (e.g., 1954), the general preference was for Australopithecus robustus (e.g., Le Gros Clark, 1967); lately support has tended to swing behind Paranthropus robustus (e.g., Wood, Wood and Koenigsberg, 1994; various contributions in Grine, 1988). The argument, however, is far from over, and Thackeray et aL (2001) have attempted to split the difference by using the subgeneric designator Australopithecus {Paranthropus) robustus for all the Kromdraai hominids (they specifically deny the presence of any "early Homo1* at the site). T h e ongoing dispute over whether the Kromdraai (as a whole) and robust Swartkrans hominids should be separated at the species level (e.g., Broom, 1950; Howell, 1978; Grine, 1981, vs. Robinson, 1954; Keyser, 2000) is, of course, irrelevant to the applicability of the species name robustus to the Kromdraai hominids (but see the morphs identified below and the concluding discussion in this volume).

MORPHOLOGY ihe Kromdraai hominid specimens include TNI 1517a and b, Brooms holotype of Paranthropus robustus.TM. 1517a is most of the L side of a cranium, still with lots of matrix, and P 1 - M 2 plus alveoli for 12, C and M 3 . 1517b is a R mandibular corpus greatly restored, with some crushed bone at the front. It contains C - M 3 ; some teeth are restored. Four complete isolated tooth crowns and four fragmentary teeth (fragments of RP 1 " 2 , two RM 3 s, and L P j . J , allegedly associated with T M 1517, bear the same number. Probably the cranium and mandible do not represent the same individual or even taxon (see concluding discussion). Given this, each specimen will be described with the others with which it appears to form a

167

morph. In the Kromdraai assemblage we distinguish four potential upper dental/cranial and two lower dental morphs, one of which is represented by a single upper M ( T M 1561) that is a possible match for the Sterkfontein StW 151 upper dental morph. T M 1517a Morph (includesTM 1512,TM 1603, KB 5222) TM 1512. R maxillary fragment, including part of the frontal process and part of the nasal cavity. It retains 1 2 - P I and M l , all very worn. The upper part of the lateral nasal margin may have been sharp, but inferiorly it becomes blunter and more rounded. Running down from this margin toward the C root region is a very low, narrow pillar that flows into the bulge of the C root. The lateral margin of the nasal aperture turns fairly sharply medially into the inferior margin, which is delineated by a very low, faint crest. It appears that the nasal aperture was fairly small and pear-shaped. Just inside the lateral margin is a low and fairly horizontal conchal crest. There is a small step down from the nasal margin to the large incisive canaL The nasoalveolar clivus is moderately long and fbrwardly sloping to just above the alveolar margin, where it curves down. The clivus was probably gendy curved from side to side, and it shows the impressions of the tooth roots. The preserved infraorbital region is shallowly concave, and the large, downwardly pointing infraorbital foramen lies moderately below it. A shallow groove runs down from the infraorbital foramen and fans out as a concavity lying above the premolar region. Midway down this groove the bone is creased somewhat to form an anteromedial margin. The infraorbital region lateral to the foramen is laterally facing and vertical. The palate was apparendy shallow anteriorly, and is quite deep by M l . It seems that the incisive foramen opened well behind the incisors. T h e preserved 12 is very tiny and spatulate (much less so and smaller than the I I ) , and was probably tallcrowned, as also was the moderately stout canine, which seems to have been narrow m/d and preserves the lower part of a stout mesial margocrista, immediately distal to which is what remains of a pronounced and very mesially placed lingual pillar. P I is rounded lingually, but is more broadly V-shaped buccally. The protocone lies slighdy mesial to the rather centrally placed paracone. The P I is about as wide b/1 as the worn M l , which is squarish. Its two buccal roots are somewhat divergent, and its stout lingual root is long

168

SITE

m/d, with a vertical groove along its midline. Although it is quite worn and is missing the lingual part of the hypocone, it is evident that the mctacone was larger than the paracolic, and that the very large protocone was quite mesially placed. The hypocone was large both m/d and b/1 (distending the tooth somewhat distally); it extended to the inner side of the metacone, and a thick postcingulum coursed between the distal side of these two cusps. It is also likely that if the hypocone was not level with the protocone lingually, it extended even farther lingually. TM 1517a. Partial cranium, substantially matrixcovered. Preserved inferolateral corner of L orbit is roundedly square. Zygoma apparently large, with a long, anterolaterally oriented surface lateral to the orbit. In profile, the infraorbital plane is oriented anteriorly and tilted up (but is not vertical). Medial to the zygomaticomaxillary suture, the infraorbital plane is shallowly concave. The L inferior corner of the nasal aperture is preserved; it is smoothly rounded, as is the lateral nasal margin (lateral crest) adjacent to it. T h e facial bone lateral to the lateral crest is flat, except for a slight concavity below the orbital region. This flatness continues down to the alveolar margin. Infraorbital foramen is downwardly directed; it lies moderately below the inferior orbital margin and continues down as a groove. A distinct "corner" mesially along this groove extends from the infraorbital foramen to the region of the C root and gives a lateral edge to the nasoalveolar clivus. The anterior root of the zygomatic arch takes origin moderately above P2, and probably ran quite strongly laterally. The zygomatic arch is long and runs up and straight back. T h e temporal fossa is capacious below, more restricted above. There appears to have been no distinction between temporal and infratemporal fossae. T h e anterior squamosal flows smoothly into the temporal fossa. The squamosal was quite short a/p and was not very tall s/i. The articular fossa is huge; it is very wide m/1, deep, extremely long a/p, and is closed off medially by a substantial flat flange of bone. The fossa is bounded in front by a fairly well-developed articular eminence, its quite steep posterior wall formed by the ectotympanic tube. The auditor)' meatus is large and subcircular, and was possibly thick-walled. The posterior root of the zygomatic arch takes origin above the anterior part of the auditory meatus; it flares quite strongly laterally, producing a moderately m/1 wide and a/p long shell above the meatus. The base of the vaginal process

ENTUIKS

is thick; it runs along the midline of the cctotympan ic tube, well in front of the mastoid region, and probabl^faded out before reaching the lateral edge of the meatus. A depression medial to the tube and behind th vaginal process may be a styloid pit or a stylomastoid foramen. Well medial and anterior to this pit lies the large, somewhat forwardly facing jugular foramen. The mastoid region is somewhat damaged. It expanded laterally and preserves the posterior part of a stout supramastoid crest that forms a border to the broad, flat posterior surface of the process. The suprameatal crest is very slight at best, and is well separated from the supramastoid crest. Medial and somewhat anterior to the articular fossa lies what appears to be a foramen (ovale?) that penetrates the cranium; posterior to this, just medial to the articular fossa, is a small foramen (spinosum?) whose internal aspect seems to be associated with what looks like an arterial groove. Medial to the smaller foramen is a chunk)' spit of bone, in a position reminiscent of the "pseudostyloid process." The palate was probably long a/p, narrow and quite shallow, deepening only minimally posteriorly. Internally, the superior surface of the petrosal is flat. The sigmoid sinus behind is deep and broad. 12 and C roots were small. P 1 - P 2 are large, chunk)' and not at all short m/d. PI is slightly narrower b/1 than P2. Both premolars have very rounded lingual surfaces and small stylar swellings on either side of the paracone. T h e preprotocristae are thicker and shorter than the postprotocristae. M 1 - M 2 are worn, but were quite tallcrowned teeth, with straight buccal sides. M2 is larger than M l , and the M 2 hypocone is much larger and more distally swollen. The M2 postcingulum is longer, and the metacone smaller, than either would have been on M l . The lingual side of M2 is more rounded than that of M l . M2 appears to have had a metaconule. O f the RP 1 " 2 fragments, P 2 is comparable in size, wear and shape to the LP 2 preserved in T M 1517a. T h e fragmentary' RP 1 is worn similarly to the RP 2 and was probably associated; it has a slightly mesially positioned protocone, a well-rounded lingual side and a thick postprotocrista that is larger than the prcprotocrista. Of the two RM's identified a s T M 1517, one is much more worn than the other. The unworn upper M 3 is large, moderately tall-crowned and low-cuspcd, and is heavily and deeply crenulated. The cusps, especially the buccal ones, arc incorporated into a cresting system that almost completely encircles the crown. The paracolic is much larger than the mctacone; it swells the crown buccally, yielding an oblique buccal

KKOMDKAAI

slope. The protocone is very large; it swells the crown lingually, yielding a lingual slope. The postprotocrista is thick, cuspulated, and runs directly to the mctaconc; the cuspulated preprotocrista swings around to the mesial side of the paraconc. The hypocone is small; it projects into the talon basin. A small pit lies on the swollen m/1 side of the protocone. The more worn M3 is very similar. Both M3s make a convincing match for the upper teeth in the cranial specimen T M 1517a (though only the more worn A13 could have come from the same individual). TM 160S. Upper L M crown resembling isolated LM 3 attributed to 1517a.

the

KB 5222. L M 3 crown: large, somewhat worn, with lots of deep crenulations, a small mctaconc appressed to a large paracone, and a thick postcingulum. T M 1517b Morph (includes T M 1600a, b, c) TM 1517b. Moderately deep, robust jaw, not notably thick m/1. The posrincisal plane was apparently not very steep (based on a small fragment). Viewed from below, the jaw appears to have been minimally arcuate across its front. There are multiple small mental foramina, three below P I and one below P2. The anterior root of the ramus takes origin from below M2, and rises moderately sharply to obscure most of the M3. There is a very narrow gutter between the M s and the ramus. 11-12 roots were small, quite m/d compressed. The C is heavily restored. P i is partially restored, but is recognizably similar to P2. Both Ps are quite large, both relative to the jaw itself and to the Ms. P 1 - P 2 metaconid and protoconid are anteriorly placed and lie opposite one another; the metaconid is large. In each there is a small anterior and large posterior fovea, each bounded by a thick cristid that comes off the metaconid, which squares up the m/1 corner in P2, while this region is more obliquely truncated in P I . T h e mesial part of M 2 has been restored. The Ms increase slightly in both m/d length and b/1 width from M l to M3. M l is quite worn; like M 2 - M 3 , it has a buccally placed hypoconulid. O n M 3 , at least, a small cuspulid lies between the hypoconulid and the entoconid. M 3 is unworn and is deeply wrinkled; the lingual cusps are somewhat compressed and peripherally placed, while the buccal cusps arc more bulbous (thus truncating the b/1 width of the m/d long talonid basin). O n all Ms, the base of the hypoconid is squared-ofF and extends

169

across the midline of the tooth. M3 and apparently M l bear a small anterior fovea. M3 has a trace of cingulid on the distal base of the protoconid. The L P , . 2 identified a s T M 1517b arc somewhat worn. Their color is different from the teeth in place in the mandible, but they arc morphologically similar. TM 1600a/l>. Fragment of L mandible, with very worn M2 and moderately worn M3. Mandible has a moderate gutter, and the ramus appears to have originated below M2. Molars arc quite large, arc modesdy elongate m/d and have very stout, widely separated, b/1 wide and m/d compressed roots. M3 retains more evidence of deep crcnulation. On M 2 - M 3 the hypoconid base is blunt, extending across the midline; the moderate hypoconulid extends slightly buccally beyond the midline. A small conulid lies between die hypoconulid and the entoconid. TM 1600c. Isolated LPj. Very worn; root long, double, bluntly wedge-shaped in outline, with an oblique lingual side. The buccal side of the tooth is angled in strongly; the lingual side is more vertical. Apparently there was a mesially placed metaconid and a thick distal crest. Plus an indeterminate piece of light bone. T M 1536 Morph (includes T M 1601a, b, c) TM 1536. A series of small, quite unworn lower teeth embedded in matrix with a little bone. Preserved are R d i 2 - d m 2 , plus M l erupting and I I developing, and L d m l and part of dc. Rdi2 is somewhat fan-shaped, with gently concave lingual and gendy convex buccal surfaces, dc was not appreciably taller than di2. dc is bulbous on its buccal side, shallowly convex on its lingual side. A low vertical pillar descends from the dc apex to a low cingulid that runs from the mesial edge of the crown back, down and up again to the distal edge. The mesial edge of this tooth is more steeply sloping than the distal edge. d m l - M l are characterized by tall, and somewhat pointed and bulbous cusps. Buccal and lingual cusp apices arc somewhat inwardly placed, with the lingual cusps taller than the buccal ones. The cusps arc distinctly separated from each other by deep grooves. d m l - M l are similarly b/1 narrow and m/d elongate, with well-developed, shclflikc trigonid basin regions, m/d long and b/1 narrow talonid basins, somewhat swollen buccal and lingual sides, and relatively large hypoconulids that lie just buccal to the midline of the «*"

170

SITE

crown. Also in d m l - M l , the pointed base of the wedge-shaped hypoconid extends just across the midline of the crown, and the protoconid and metaconid arc slightly more approximated than the hypoconid and entoconid (thus, the crowns arc narrower mcsially than distally). The d m 2 - M l entoconid lies slighdy distal to the hypoconid. dm2 has a well-developed conulid between the metaconid and entoconid. TM 160fa. Rdm, with divergent roots. TM1601k LP 2 . TM 1601th uncruptcd crown of LP,. P 1 - P 2 are similar in having deeply crenulatcd enamel and a mcsially positioned protoconc; an even more mcsially positioned metaconid; small anterior and much larger posterior fovcac; and a ridge coming down the internal surface of the protoconid. PI is subequal to P2 in b/1 width, but is slightly shorter m/d. P2 is roundedly square; PI is wedge-shaped, with an oblique lingual side. TM 1601c is a C crown (probably lower; right), with its root just beginning to form. It is quite tall-crowned but not pointed, with a short, gently sloping mesial edge and a longer, steeper distal edge. The buccal side is somewhat bowed; the Ungual side is shallowly excavated, with a thin pillar running from the apex down to the swollen base of the tooth. The distal margocristid is relatively thick; the mesial one is thinner. There are thin marginal pillars on the buccal side. In buccal view, the mesial oudine of the crown forms a smooth curve. T M 1601c Morph (includes KB 5383) TM 1601 e. Uncrupted crown of LM 1 or M 2 . Crown is only moderately large, and is much longer m/d than wide b/1. The hypocone is large, and distends the tooth d/1. The paracone and metacone are subequal in size, well separated. A thin postprotocrista arcs broadly from the large protoconc up to the apex of the metacone, and a thin prcprotocrista arcs broadly around to meet the paracone. The thick postcingulum bears a few conulclikc structures, and encloses a m/d narrow basin. KB 5383. A partially damaged and probably uncruptcd crown of an upper R molariform (M 1 according to the accompanying note by Grine). T M 1604 Morph (includes KB 5503 and probably also KB 5223) TM 1604. Chunk of matrix with a somewhat damaged and very worn Rdm,. Very large trigonid

ENTRIES

basin- Much larger than comparable teeth in T\I 1517; unlikely to be conspecific. Closer to KB 5503 * KB 5223. Some bone fragments and assorted isolated lower teeth: L and Rdi,, Ldi2, RI n and Ldm, and M l . The dis are tall-crowned and in/d narrow, with slight lateral flare. di2 is more flared laterally. The I I crown is moderately tall and m/d narrow, with some flare. The dm2s are quite worn but retain some deep crenulation. The)' have two basins mesially: a broad paraconid shelf at the edge of the crown, and a narrow but deep basin between the protoconid and metaconid. The metaconid and entoconid are somewhat compressed and peripheralthe protoconid and especially the hypoconid are bulbous and internally placed; a distinct metastylid is present. The dm2 hypoconulid is large and wedgeshaped; it extends farther buccally than lingually. There is a deep, wedge-shaped notch between the protoconid and hypoconid, and a smaller but still distinct notch between the hypoconid and hypoconulid. The M i s are relatively long m/d and narrow b/1, with a narrow paraconid shelf low across the bases of the protoconid and metaconid. Mis are slighdy bulbous on their sides. They are somewhat tall-crowned with bulbous, not very projecting cusps that fill in the talonid basin; they have small metastylids and a ledgelike buccal cingulid at the distal part of the base of the protoconid. The base of • the hypoconid extends slightly across the midline of the crown. The hypoconulid is large, and more buccally than lingually placed. A fairly large, deep, Dshaped and d/1-facing basin lies between the hypoconulid and entoconid, and is defined by crests that run between the apices of these cusps. KB 5503. Rdm 2 crown: differs from KB 5223 in that the mesial pair of basins is relatively larger and the hypoconid not as extensive; also, a cuspulid lies between the hypoconid and entoconid. Possible S t W 151 Upper Dental Morph (includes T M 1561) TM 1561. RM 2 or M \ somewhat worn. Longer m/d than wide b/1, and narrows b/1 distally from the paracone through the metacone to the postcingulum. T h e trigon basin is constricted b/1, and the preprotocrista is worn away. Hypocone is bulbous, somewhat m/d compressed, and quite internally placed; buccal to it is a large cusplike structure. A thin and short

K ROM h RAA f

postcingulum runs between these two eminences along their distal sides. T h e lingual surface of the protoconc is grooved, and bears a small portion of cingulum mcsially. T h e M 2 s of T M 1517a and S t W 151 arc similar in terms of the distally b/1 narrowing shape, with the protoconc projecting dominantly lingually. However, the mctaconc is smaller on S t W 151 than on T M 1517a, and the former possesses a fairly well-developed conulelikc structure within its thick postcingulum, b/1-oricntcd horizontal grooves on the distal margin of the protoconc, a mctaconulc-likc structure in the postcingulum, and some protoconc lingual pocketing. All of these features lend t h e m selves to identifying T M 1561 as an M 3 in a s i z e shape gradient in which these various features are increasingly emphasized. Unassignable t o M o r p h TM 1602. Fragment of R palate with M roots. Palate became shallow rapidly posteriorly; otherwise, this specimen is uninformative. KB 5063. Upper R molariform unerupted crown, identified as d m 2 ( M 1 in accompanying note b y Grine). Crown is very small, squarish and distended slightly d/1 by a large hypocone. Paracone, protocone and metacone are subequal in size; a paraconule lies mesial to the junction of the paracone and protocone. A postprotocrista runs to the base of the metacone, and a low crest runs u p its face. T h e postcingulum is moderately thick; it runs from t h e side of the m e t a cone distally around to the hypocone, bears a small conule, and encloses a small basin. T h e lingual side o f the tooth slopes; its buccal side is m o r e vertical. T h i s tooth is hard to identify, a n d thus to interpret. KB 5226. Uninformative lower M fragment.

REFERENCES Brain, C. K. 1958. T h e Transvaal Ape-Man-Bearing Cave Deposits. Mem. Transvaal Mm. 1 1 : 9 5 - 9 9 . Broom, R. 1938. The Pleistocene anthropoid apes of South Africa. Nature 142:377-379. Broom, R. and G . W . H . Schepen. 1946. The South African fossil ape-men: the Australopithecinae. Transvaal Mus. Msncrr. 2:84-109,113-118. Broom, R. 1950. T h e genera and species of the South African fossil ape-men. An. J. Phys. Anthrcpcl. 8 : 1 - 1 4 .

171

Clark, VV. E. Le Gros. 1967. Man-Apes or Ape-Men? New York: f lolt, Rinchart and Winston, Grinc, F. E. 1981. Trophic differences between "gracile" and "robust" australopithccincs: a scanning electron microscope analysis of occlusal events. 8. Afr. J. Set. 77:203-230. Grinc, F. E. 1982a. A new juvenile hominid (Mammalia, Primates) from Member 3, Kromdraai Formation, Transvaal, South Africa. Ann. TransvaalMm. 33:165-239, Grinc, F, E. 1982b. Note on a new hominid specimen from Member 3, Kromdraai Formation, Transvaal. Ann, Transvaal Mm. 33:287'-290. Grine, F. E. (ed.). 1988. Evolutionary IHuary of the "Robust* Australopithecines. New York: Aldine de Grirytcr, Howell, F. C. 1978. Hominidae. In: V.J. Maglio and H. B, S, Cooke (eds), Evolution of African Mammals. Cambridge, MA: Harvard University Press, pp. 154-248. Keyscr, A. W, 2000, The Drimolcn skull: the most complete australopithecine cranium and mandible to date. S.Afr.fSci. 96:189-193. Kuman, FC, A, S. Field and J. F,Thackeray. 1997, Discovery of new artefacts at Kromdraai. S.Afr.f Set. 93:187-193, McKec, J.,J. F.Thackeray and L, Berger, 1995, Fauna! assemblage seriation of southern African Pliocene and Pleistocene fossil deposits. Am. J. Phys. Anthropol. 96: 235-250. Partridge, T. C, 1982. Some preliminary observations on the stratigraphy and sedimentology of the Kromdraai B hominid site. Palaeoecoi Afr. Surrounding hi. 1 5 : 3 - 1 2 , Robinson, J. T. 1954. The genera and species of the AIMtraIopithecinae./tf/?z./ Phys. Anthropol. 12:181-200, Thackeray, J. F. et al. 2001. Hominid fossils from Kromdraai: a revised list of specimens discovered since 1938. Ann. Transvaal Mus. 38:43 - 5 6 . Vrba, E. 1975. Some evidence of chronology and palaeoecology of Sterkfontein, Swartkrans and Kromdraai from the fossil Bovidae, Nature 254:301 - 3 0 4 , Vrba, E. 1976. The fossil Bovidae of Sterkfontein, Swartkrans and Kromdraai. Mem, Transvaal Mm. 21:1 - 1 6 6 , Vrba, E. and D . Panagos. 1982. New perpectrves on taphonomy, palaeoecology and chronology of the Kromdraai ape-man. Palaeoecoi. Afr. Surrounding hi 15:13-26. WoIpotT, M . 1973. Paleoanthropology. New York; Knopf. Wood, B„ C. Wood and L. Konigsberg. 1994, Paranthropus hoisei: an example o{ evolutionary stasis? Am. J. Phys. Anthropoid: 117-136.

Repository Transvaal Museum (Northern Flagship [nttrtunoflj, P O Box 43, Pretoria 0001 r Gaureng, South Africa.

SITE

KROMDRAAI

KROMDRAAI

ENTRIES

Figure 1. KB 5223, lower molariform teeth (scale = 1 cm).

Figure 2. From L to R: KB 5223, T M 1604, KB 5503, lower dm2s (scale = 1 cm)

KROMDRAAI

KROMDRAAI

Figure 3. TM 1512, partial R maxilla (scales =s 1 cm).

173

174

Sure E#r**e*

KROMDRAAI

Figure 3- {Continued).

KuuMhUAAl

175

Figure 4. Top row: TM 1517, upper R molariforms; Bottom row: lower LP2 and lower LP1,TM uncat (scale • 1 cm). KROMDRAAI

Figure 5. Top row: TM 1517; bottom row, L to R: KB 5063, KB 5383, TM 1601c, various upper molariforms (scale - 1 cm).

KROMDRAAI

176

SITE

ENTRIES

Figure 6. Top row: TM 1517; Bottom row, L to R: KB 5222, TM 1603, various upper molariforms (scale = 1 cm). KROMDRAAI

KROMDRAAI

KROMDRAAI

177

Figure 7. TM 1517a, partial cranium (scales = 1 cm).

INSTfTUT D€

PAieO^TJOLOGiE MufcttftNE

178

SITE ENTRIES

KROMDRAAI

Figure 7. (Continued).

KROMDRAAI

KROMDRAAI

Figure 8. TM 1517b, partial R mandibular corpus (scales = 1 cm).

179

Ik

I 180

SITE

Figure 9. Left: T M 1520, lower RM; Right: T M 1561, upper RM (scale = 1 cm).

KROMDRAAI

ENTRIES

KROMDRAAI Figure 10. L: TM 1536, partial R mandibular corpus: R: TM 1601a, lower Rdml (scale = 1 cm).

ELROMORAAI

KROMDRAAI

Figure 11. TM 1600a and b,. lower R molars (scales == 1 cm).

181

LAETOLI

(Laetolil, Garusi)

LOCATION An area of sedimentary exposures (approx. 30 sq. km) containing numerous hominid and other fossil localities in the Scrcngcti Plains of northern Tanzania, about 40 km S of Olduvai Gorge and in the divide between the Olduvai and Eyasi drainage systems (Map 3).

Garusi maxilla, the holotype of Weinert's (1950) Meganthropus africanus, is plausibly contemporaneous with the documented fossils from the Laetolil Beds (White, 1977), as is the lower L canine tooth BMNH M 18773, originally collected in 1935 (White, 1981). See Volume 2 of this series for the much later LH18 cranium.

DISCOVERY A hominid canine tooth was recovered during a survey by L. and M. D. Leakey in 1935, but went unrecognized for several decades. L. Kohl-Larscn made an unprovenanced collection in the area in 1939. Later explorations at Laetoli developed out of Hcldwork conducted at the neighboring Olduvai Gorge by the Leakeys. The first hominid fragment of the modern scries (LH1) was discovered by M. Muoka in 1974, and field activity at Laetoli continued through 1981, though work subsequent to 1976 was almost entirely devoted to the trackways, the first of which was discovered in that year.

DATING AND STRATIGRAPHIC CONTEXT The history of geological exploration in the Laetoli area and the current understanding of the regions geology have been summarized by Hay (1987). The majority of hominid fossils from the region derive from the Laetolil Beds. These are composed principally of tuffaceous materials, and are divided into a largely unfossiliferous Lower Unit and a much richer Upper Unit. Above the Laetolil sediments lie the equally fossiliferous and tuffaceous Ndolanya Beds, capped locally by the Ogol Lavas, above which lie the thinner Naibadad, Olpiro and, finally, Ngaloba Beds. The relatively recent hominid cranium LH1S (see Volume 2 of this series) derives from the Ngaloba Beds, while the hominid fossils of interest here come from the Upper Unit of the Laetolil Beds. The Upper Unit is bracketed below by a K/Ar date on tuffderived biotite of 3.76 Ma, and above by a series of K/Ar dates clustering closely around 3.49 Ma (Drake and Curtis, 1987). The fossiliferous Upper Unit sediments thus span approximately 0.3 Ma. The famous Footprint Tuff, deposited over a span of only weeks, is approximately 3.5 Ma old.

MATERIAL White (1977) lists 14 Laetoli hominids resulting from ficldwork in the 1970s; these arc mostly isolated teeth, but include the mandibles without corpora LH2 and 4, and the mandibular fragments LH10 and 13. The total of individually numbered hominid fossils from Laetoli is now variably 26 or 29, almost all from the Laetolil Beds. In addition, Kohl-Larscn s fragmentary

182

LAKTOLI ( L A E T O L I L ,

ARCHAEOLOGICAL CONTEXT Stone artifacts have been recovered from the Ngaloba Beds, both in situ and on the surface. I lowevcr, the earlier hominids from Laetoli have no archaeological associations. PREVIOUS DESCRIPTIONS AND ANALYSES The hominids from the Laetolil Beds were initially described by White (1977), without taxonomie assignment or other comment. However, they were soon co-opted by Johanson, White and Coppens (1978) as the t\"pc materials for the new species Australopithecus afatrnsis, of which the vast majority of the hypodigm was from Hadar, in Ethiopia. This was a grand statement o( faith on the part of these authors, assuring that the ancient Laetoli hominids will continue to bear a geographically inappropriate name whatever the taxonomie fate of the materials from I ladar. Although initial protesters such as Tobias (1980) saw no specific difference between the East African A. afarensis and the South African A. africanusy nobody has recently questioned that the hominids from the Laetolil Beds represent a distinctive form of Australopithecus that deserves specific recognition, perforce as W. afarensis. Nor has there been any suggestion prior to this contribution that the hominid assemblage from the Laetolil Beds is not itself homogeneous as to species. Johanson and White (1979) saw the Laetoli/ Hadar Australopithecus afarettsis as a putative ancestor for all subsequent hominids, but the recent description of the penecontemporaneous Kenyanthropus platyops by M. G. Leakey et al. (2001) will presumably reopen this question. MoRPIIOLOGY Hominid material from Laetoli consists primarily of dentognathic specimens that have been identified as Laetoli Hominids (LI 1) 1-26. However, these "individuals" do not necessarily constitute morphologically consistent groupings. Wc have tried to organize this material roughly into such groups, but further refinement will probably be necessary. As with other sites, in the absence of positive associations between upper and lower jaws/dentitions the most secure groups or morphs arc limited to cither upper or lower. In the Laetoli collection, as indicated below, we cautiously suggest an association between the first two morphs we describe: the L H 2 morph, and the L H 3 morph (which seems not to be hominid in the sense used in

GAKUSI)

183

these volumes, but rather to be hominoid with some Mm^a-likc affinity). The LH4 morph includes the LH4 mandible, the type specimen o( Australopithecus a/arrttsis, and is thus the definitive morph for this species. As a lower dental morph, it is described separately from the upper dental LI 15 morph. 1 lowevcr, it seems reasonable to associate the LI 14 lower dental and LH5 upper dental morphs in the same taxon— which includes the original Garusi fragment. This arrangement still leaves several specimens indeterminate as to morph, and all of these arc individually described, as indeed arc all LI 1 specimens. LI I 2 Upper and Lower Dental Morph (includes LI I3i, 3j, 3k, 3q, 3s, 6,3/6a) It might be reasonable to consider this and the following morph together, especially since LH2 and LI 121a arc of similar dental age. Ut2> Juvenile mandible lacking rami and part of inferior corpus, especially on the L. Preserved arc the alveoli of all four deciduous incisors, partial crowns of the des, plus the dm Is thrcnigh M i s . Also exposed in the damaged front of the jaw arc the crowns of the l i s , and on the L the developing crown of the C anil P L O n the R, only glimpses of the developing C and P I crowns arc exposed. T h e front of the jaw is broadly curved from side to side, and the external parts of the corpora arc more divergent than the tooth rows. In profile the symphysis is gently sloping superiorly, but it then curves back more strongly interiorly. There arc no signs of digastric impressions on the inferior margin, and the genial region is too damaged to characterize, I he postincisal plane is long and slopes only moderately. The anterior roots of the rami begin to rise level with M l , which would have been partially masked by the ramus. T h e crowns of the permanent l i s appear to be developed fully to the neck. They arc very tall and their mesial and distal edges would probably not have been very divergent. The dil roots arc circular in cross section, and much smaller than the more laterally compressed di2 roots. All di and ilc mots appear to be quite long, those of the des perhaps much longer than the subequal d i l - d i 2 roots. On the complete l\dc the mesial edge is steep, somewhat distended, and delineated lingually by a crease. The distal edge is more noticeably vertical; lower down it turns almost at a right angle to expand into a fairly well-developed heel that

184

Sin;

is swollen on the lingual side. In profile, this tooth is tall and moderately tapering superiorly. Lingually, a thin and low crest descends almost straight down from the apex, subdividing the surface into a very shallow but large mesial moiety and a smaller distal moiety that is truncated by the swollen heel. The dm Is have two broadly divergent roots. A stout paracristid descends directly medially from the tall and somewhat internally placed protoconid, kinking sharply backward to terminate at the base oi the mctaconid to enclose a vertically oriented, mcsiolingually facing trigonid basin. The well-developed and somewhat bulbous mctaconid lies close to and slightly behind the protoconid, which is slightly the taller of the two cusps. The short hypoconid lies right at the base of the tall protoconid. The bases of these buccal cusps, especially the protoconid, are quite swollen, extending outward over the roots. The very small cntoconid lies at the base of the mctaconid, and on the L a cristid connects the two. On the R a small hypoconulid is preserved at the base of the cntoconid lingual to the midline of the tooth. The dm2 roots appear not to have been very divergent. The dm2 crowns are relatively long m/d and somewhat narrow b/1, taper somewhat mesially and are distended somewhat distally by a shelflike notch between the entoconid and the somewhat buccally placed hypoconulid. T h e buccal side of these teeth is more sloping than the lingual. There is a fairly deep, wide and fairly vertically oriented trigonid basin, bounded by a fairly thick paracristid, which is bounded distally by (as seen on the less worn Rdm2) a somewhat bulbous mctaconid and protoconid. The apex of the mctaconid lies slightly mesial to that of the slightly taller protoconid. The base of the large hypoconid extends slightly across the midline of the tooth, and buccally is separated from the much smaller hypoconulid by a deep groove that flows into the notch between their bases (thus the hypoconulid is sharply delineated by notches on either side of it). On both dm2s there is a distinct, moderately developed talonid basin lying lingual to the midline. The buccal cusps are more internally placed than the lingual; thus the talonid basin is somewhat constricted and lingually placed. The M i s are reconstructed, the R being more complete than the L. Both teeth have minimal root development, but the crowns appear to have erupted. The enamel surface is thickly wrinkled. There is a thin but distinct trigonid basin bounded mesially by a thick paracristid. The basin lies between the bases of

KNTIUKH

the rather large and subequal mctaconid and n r conid, the apices of which arc rather mesially situated" The mctaconid and somewhat smaller hypoconid separated by a deep b/1 and tall s/i vertical groove A thinner but equally tall groove that terminates in a slight shelf separates the hypoconid from the hypoconulid, most of which lies just buccal to the midline. A short, thick shelflikc hypocristid with ^ small posterior fovea intrudes between the hypoconulid and cntoconid, whose apex lies slightly distal to that of the mctaconid. In turn, the base of the mctaconid extends slightly lingually across the midline of the tooth. The buccal cusps arc more centrally placed than the lingual, imparting a steeper slope to the buccal side. LII3L Fragment of a M with wrinkled enamel. LH3j. Fragment of a tiny I, probably deciduous. Possibly associated with LI I3i and q. Little. Broken crown of a Ldc 1 . May be associated with 3i and q. Uttq. Highly worn Rdmj (listed as a molar). It had a distinct, large trigonid that was somewhat higher than the b/1 broader talonid. The protoconid and mctaconid lie close to each other, and were probably connected by a crest. Running mesially from the protoconid is a stout paracristid. There arc vestiges of a very large trigonid basin that may have been enclosed by the paracristid. The distal region lacks enamel, but the lingually placed hypoconulid was very close to the cntoconid, from which it is separated by a small groove. The cristid obliqua was arcuate, curving in the direction of the mctaconid and offset buccally by a definite hypoflcxid notch. Cf. the dm! in LH2; probably associated with 3i and k. Utts. Broken lower RM crown, with some cingulid around the protoconid and a thick paracristid connecting the bases of the protoconid and mctaconid. A small trigonid basin lies behind the paracristid and between the bases of the cusps. Cf. 2. Utt/6a. Very worn, slightly possibly counterpart to 3k.

damaged

Rdc;

Ul3/6b. Very worn, slightly damaged Ldm 2 with a strong lingual slope, constricted trigon basin, distinct parastyle and small mctacone with thick postcingulum. Possibly of the same sort of hominoid as 3i, k and q.

LAKTOLI

(LAETOUL,

LH 3 Upper Dental Morph (possibly nonhominid; includes LH 3a, 3b, 3c, 3d, 3c, 3h, 3n, 3o, 3t, 6c, 7, 21a) LH3a. A RM 1 , with some maxilla attached. The occlusal outline is rectangular. The protocone and hypoconc arc internally placed and there is a steep lingual slope. There is a small constricted trigon basin and a large deep talon basin. The prccingulum parallels the prcprotocrista. The lingual root is divergent. LH3b. A slightly worn upper L I I , with a broken root. The huge crown is very tall, with a rather wide incisal edge. The distal edge is somewhat divergent but not markedly flaring. The lingual surface is concave and somewhat wrinkled, with distinct twinned lingual swellings as the bases of low pillars. LH3c. A LI 2 crown fragment with a deeply concave lingual surface; cf. 3d. LH3d. A LI 2 crown with a broken root. It is small, somewhat narrow and tall crowned. The mesial edge is rather vertical and the distal edge modestly flared. The incisal edge is steeply curved distally and the lingual surface is strongly concave, with a distinct basal swelling. LH3e. A somewhat damaged LC 1 crown. This is a very chunk)' crown with a virtually circular section at the neck. In buccal outline, the crown is a broad-based triangle with equally long and divergent mesial and distal edges; buccally, just in front of the distal edge, is a modest and thin vertical groove. The lingual surface is somewhat wrinkled and bears two parallel pillars set so that the mesial fovea is not as expansive as the distal one. A lingual cingulum courses around the base of the crown, peaking in a slight swelling in the midline. LH3h. RM 1 with broken root tips. The enamel surface is broadly wrinkled, but originally there was probably more wrinkling and surface detail than now exists. The large paracone and slightly more buccally placed mctaconc arc subequal in size and quite closely approximated, while the much larger protocone and subequal hypoconc are set farther apart (thus the crown has a trapezoidal outline). The trigon basin is constricted and there is a steep lingual slope. There is a protostylar pit mesially on the protocone and a somewhat deep and m/d long vertical notch between the bases of this cusp and the hypoconc. What

185

G A KITSI )

appears to be a stout prcprotocrista courses quite strongly mesially and somewhat buccally to the mesial edge and then turns straight up to terminate at the side of the paracone. There is nodular crcnulation in the region of the postprotocrista. A stout but very b/1 short postcingulum emerges from the hypoconc and quickly fades out along the side of the mctaconc. The hypoconc is distally swollen, making the lingual m/d length of the tooth slightly greater than the buccal. The cusps arc compressed from side to side. Ul3n. Short, stout LC 1 crown. In buccal outline the mesial edge is short and moderately sloping while the distal edge, which terminates in a broad swelling below which lies a shallow depression, is much longer and slightly steeper. The mesial edge ends in a much taller vertical swelling that is delineated from behind by a thin vertical buccal groove. There is a much more marked buccal groove mesial to the distal edge. Lingually there is a tall and distally offset pillar that is deeply incised by a tall, thinly triangular distal groove. Mesially this pillar slopes down to a broad, shallow fovea that is also bounded by a large mesial margocrista. Cf. 14e, and also OH62 RC 1 . LH3o. Probable RC 1 fragment; counterpart of 3n. LH3t. Lower LM lacking a distal interproximal facet (juvenile, M l , subadult M2 or adult M3?). The enamel is thickly wrinkled, and there arc deep fissures between the cusps and some cingulid around the protoconid. The buccal cusps are centrally placed, with a strong buccal slope. The lingual cusps, especially, are compressed from side to side and peripherally placed. A moderate paracristid runs between the mesially placed protoconid and mctaconid apices; a b/1 wide and deeply incised trigonid basin lies behind the cristid and between the cusp bases. The protoconid is smaller than the mctaconid, but their apices lie opposite each other. The hypoconid is the largest cusp and its base just crosses the midline of the crown. The entoconid is subequal in size to the protoconid. The hypoconulid is moderately large but is still the smallest cusp. It is centrally placed, with a small posterior fovea between it and the hypoconid. LH6e. RM 1 , with some alveolar bone adherent. The cusp tips arc only minimally worn. The occlusal surface is slightly roughened. There is faint cingulum development lingually and distally at the base ot the internally placed and rather broad protocone. There is a relatively large and mesially placed protostyle, and a

r%*«+\jyT% K>mVT*?!?*}T*

^"C

186

SlTK ExTUIKS

moderate but quite distinct lingual notch between the side of the protocone and the moderate hypocone that projects a bit more lingually. The fairly large paracone lies opposite the protocone, from which a thick preprotocrista broadly arced mesially to the side of the paracone. An apparently low, broad postprotocrista ran from the base of the protocone up the face of the smallish metacone. Thus the trigon basin is constricted b/1 and also shifted buccally because of the internally placed protocone. The m/d somewhat compressed, but b/1 wide hypocone lies more distally than the metacone, giving the tooth a trapezoidal shape, with the lingual side longer m/d than the buccal. A thick, beaded postcingulum runs from the distal side of the h)pocone along the side of the metacone, enclosing a very narrow basin. The lingual side of the tooth is more sloping than the buccal side, which is slightly swollen toward the neck. The large lingual root diverges markedly from the two thinner, more closely approximated buccal roots. Cf. 3a. LH7 (Locality 5). Fragment of upper KM. It would have had a steep lingual slope, a somewhat trapezoidal shape and wrinkled enamel. Cf. 3h and 6e. LH21a. Consists of the broken crown of an I I , the crown of 12 (both Is just beginning to erupt), the root of dc, the crowns of d m l and dm2, plus the M l crown is beginning to erupt. I I is broad and was spatulate; it lies direcdy over the narrower 12 crown. The dc root is grooved buccally and oriented m/d. d m l - d m 2 have three divergent roots. M l is much smaller than dm2; both have a distinct but narrow trigon and a well-developed postprotocrista and large talon basin enclosed by a distally arcuate postcingulum, and a large but compressed and basally swollen hypocone. d m l is swollen m/b over the root and has a small metacone appressed to the paracone. In dm2, the metacone and paracone are subequal. In both dms the buccal cusps are compressed and quite peripheral. In both the protocone is more internal, and its lingual surface is sloped. dm2 has a deep, large, mesially placed protostylar pit. The M l crown is quite long m/d, rounded distally and quite cuspulated, with a broad mesial protostylar pit. Protocristae are broadly divergent from somewhat compressed but slightly internal protocone. The buccal cusps are compressed and slightly internal. The preprotocrista courses mesially around the paracone to terminate at its side. The distally arcuate postcingulum and the compressed hypocone enclose a large talon basin.

The palate (as expected in a juvenile) is very shal low indeed. There is a slight backward slope of th" floor of the nasal cavity behind the crypt for 11 T ^ inferior part of the lateral nasal aperture is present and slightly curved inward in the frontal view. It is al rounded out from the nasal cavity onto the face. Th nasoalveolar d i m s was probably quite long and curved strongly down from the nasal opening. Posteriorly, the clivus appears to have extended somewhat into the nasal cavity at a low angle, with appreciable overlap of the palate. The R incisive canal is quite long and also runs at a low angle. What is preserved of the anterior extent of the palate is thin at its extremity and thickens behind, following the ancle of the incisive canal. Posterior to what would have been the R incisive fossa, the thick palate appears to angle downward before the point of breakage. The shape and details of the M l of this specimen are consistent with the more worn 6e and the more fragmentary 3a. L H 4 Lower Dental Morph (Australopithecus afarensis morph; includes LH31,3p, 3r, 12, 14h,14i,14j,24) LH4. Holotype of Australopithecus afarensis. Adult mandible lacking both rami, parts of posterior corpora and the anterior teeth, plus some bone in this region. The RC is broken, but P2-M3 are present and in good shape except for M2; LP2-M2 are present. Mandible. A moderately robust jaw, reasonably tall s/i for its width b/1. The corpus tapers markedly back from the symphyseal region, which is quite long from front to back. Anteroposteriorly this would have been quite a short jaw. At the level of M2 the corpora are not very broad b/1; they thin markedly inferiorly. From above, there is a fairly strong curve across the moderately broad front of the jaw and the tooth rows are only minimally divergent posteriorly. In profile, the symphysis descends straight down from the alveolar margin, then curves very strongly back to the inferior margin. This latter margin is thickened posteriorly into a modest inferior transverse torus. The postincisal plane, damaged above, was not very long, but is quite horizontal where preserved. It terminates fairly low down, and is separated from the inferior torus by a deep, moderately broad, subcircular genial pit. At the center of the pit lies a tiny depression below which a thin crest descends to terminate in two moderately developed genial tubercles that lie on the

LAETOLI (LAETOLIL, GARUSI) posterior surface of the inferior transverse torus. A piece is missing from the symphyseal region where the jaw was broken in half; however, there is a continuous "digastric depression" that runs right across the midline between the canines and points down and quite strongly backward. On the R is another small depression a bit posteriorly and laterally. The digastric fossa is bounded in front by two muscle-scarred elevations that are well separated in the midline. Internally, especially on the R, there is a faint mylohyoid line below which, under and restricted to the region of M 3 , lies an almost undetectable submandibular depression. Externally on each side is a relatively large mental foramen that lies under the anterior root of P2. On the R is a tiny accessory foramen just above and in front of the main one. The region above and behind the foramen is slightly depressed. The anterior root of the ramus takes origin at the region of the M2 (thus M3 and part of M 2 would have been masked from the side by the ramus). Teeth. The alveoli of both l i s and the LI2 are partially preserved. All are laterally compressed, with the lis being smaller than the I2s. Part of the alveolus for RI1 and part of that for RI2 are modified by reactive bone, which affects the front of the mandible in the region between these alveoli and extending to the C. The RC root and part of the L C root are preserved. They are oriented obliquely and distally, are robust but not extraordinarily so, and, as judged on the R, are not very long. The damaged RC crown was probably not originally very broad. The remaining teeth are relatively to considerably worn, removing much surface morphology. The P i s are double rooted, with the mesial root being strongly obliquely oriented, and the distal root transversely oriented. The crown of the RPl has a very strong buccal slope, with the enamel bulging over the anterior root. The apex of the protocoled is quite centrally placed and a short paracristid descends from it to kink inferiorly distally, terminating mesially at the base of the metaconid and enclosing a very small, somewhat lingually facing and vertically oriented trigonid basin. Below the terminus of the paracristid the enamel is thickened into a low pillar that is accentuated by a depression lying distal and parallel to it. It appears that a stout but short crest ran lingually from the protoconid apex and swelled into a small metaconid that lies somewhat below and slightly mesial to the protoconid. Distal to this crest is a modest, apparently shallow, vertical and lingually facing talonid basin. The occlusal outline of the P I is

187

somewhat triangular. The very worn P2 is about as wide b/1 as the P I , with the lingual side of the tooth being rather straight and the buccal side broadly arced; on the LP2, there is a shallow notch in the buccal side, just distal to the protoconid, where one would expect a thick postcingulid to have terminated. The protoconid and apparcndy subequal metaconid opposite it are mesially positioned, so that an anterior fovea would have been small and the posterior fovea larger. The M i s are highly worn, and missing various bits of enamel. As best seen on the L, the tooth is rather narrow b/1 and elongate m/d and was probably somewhat roundedly rectangular in occlusal outline. The protoconid and metaconid are placed well forward on the tooth, and what appears to be a little wedge of cingulid intervenes between the protoconid and the also somewhat forwardly placed hypoconid. The apex of the entoconid lies somewhat behind that of the hypoconid, whose base appears to have extended lingually across the midline of the tooth. The region of the hypoconulid is quite narrow m/d but rather broad b/1, and straddles the midline of the tooth, with a larger buccal than lingual component. On the buccal side the hypoconulid does not extend quite to the hypoconid, from which it is separated by a small indentation. Wear precludes knowledge of a trigonid basin or paracristid. As judged from the L, cusp configuration of the M 2 is generally similar to that of the M l , except that the entoconid lies more opposite the hypoconid, and the buccal side of the tooth appears more bulbous. In both teeth, the buccal cusps are slightly more internally placed than the more peripheral lingual cusps. The M2 is longer m/d and appreciably wider b/1 than M l , and thus not as narrow. This tooth was also probably roundedly rectangular and also has a slight indentation between the hypoconulid and hypoconid. The preserved RM3 is somewhat worn. There is some evidence remaining of enamel wrinkling. The metaconid and protoconid are right at the front of the tooth, with no indication of a trigonid or a paracristid. A moderately deep groove separates the metaconid and protoconid, and another separates the hypoconid from the hypoconulid. The entoconid lies opposite the hypoconid, and is separated by a moderate shelflike notch from the broad and somewhat centrally situated but slightly lingually truncated hypoconulid. A smaller shelflike notch separates the hypoconulid from the hypoconid. The buccal cusps are more centrally placed than the lingual ones, so the shallow talonid basin lies lingual to the

188

SITE

midline. The M 3 is longer m/d than the M2, and probably as wide mesially; but it tapers somewhat distally. Thus the outline is not rectangular. LH3L RP 2 crown, probably unerupted, with deeply and markedly wrinkled enamel. The trigonid basin is distinct but the talonid basin is much larger. The somewhat centrally shifted and buccally bulging (thus internally placed) protoconid, and the slighdy shorter and only slighdy internally placed metaconid, lie opposite each other and mesial to the midline. A low crest runs mesially down the face of the protoconid, then lingually and up to the apex of the metaconid, enclosing the front of a very shallow, vertical and mesially facing trigonid basin. A thicker crest between the bases of the mesial cusps encloses the basin from behind. A very thick postcingulid courses from the protoconid in a slight arc to the d/1 "corner" of the tooth, and then strongly curves in to the base of the metaconid (thus giving the tooth a buccally narrow, lingually m/d long outline). The cusps are compressed from side to side. LH3p. RP l f strongly distended m/b at its base. A paracristid runs m/1 down from the protoconid, kinks sharply at the base, and then runs distally to the base of the metaconid. This creates a tall, vertically oriented and lingually facing trigonid basin. The metaconid is slighdy smaller, closely appressed to, and set slighdy distal to the essentially centrally placed protoconid. The large talonid basin is enclosed by a thick beaded crest that runs distally down the face of the protoconid and then swings d/1 to distend the tooth distally before curving sharply inward to the metaconid. Cf. 4. LH3r. LP 2 ; essentially a mirror image of 31. LH12 (Locality 5). Fragment of RM 3 , deeply wrinkled and distally rounded. Cf. 4? LH14L LPj, crown slighdy broken, with a very stout, long, compressed, bifid root. The crown is large and distended m/b, with a strong buccal slope. It is straight distally and tapers mesially because the lingual side is m/l-b/d oblique, thus giving it a righttriangular outline. The protoconid is tall, with long mesial and shorter distal edges that are quite divergent; it bears a slight distal pillar buccally. A stout paracristid courses mesially down the protoconid and kinks back at the base toward the base of the metaconid, from which it is partially separated by a

ENTRIES

crease. This creates a small, vertical and lingualK faci ng anterior fovea. A thick crest also courses distally from the protoconid, arcing distally around to terminate thickly as a cingulid low down on the d/1 side of the metaconid base. This creates a sliehdv larger, vertical and distally facing posterior fovea. The metaconid is somewhat smaller than, and not as tall as, the protoconid lying opposite it. LH14j. RPj, quite similar to 14i. The crown is worn and damaged and one root tip is missing. The protocone is complete (its shape is like 14i) and part of the metacone is present (also like 14i). Cf. 4? LH14h. Most of a RM 3 , very worn and weathered. The enamel appears to have been very wrinkled and the back of the tooth very rounded. The roots are divergent, but not markedly so. Cf. 4? LH24. RP 1 , worn, broken, and had three roots. Cf. 14i. L H 5 Upper Dental Morph (includes LH1,3f, 3g, 6c, 8,11 and Garusi maxilla) LH5. A very incomplete R maxillary fragment, basically consisting of I 2 - M 3 and the alveolar bone holding them together. All teeth are worn, some extremely. Where preserved, all teeth have severe linear hypoplasia buccally. The 12 has a compressed, moderately long root, and the crown would have been very narrow m/d, with a very shallowly concave lingual surface terminating in a modest lingual swelling. The slighdy distally curved C root is not very long or stout. Its crown was not originally much taller than at present and would have been broadly triangular in buccal outline, with subequal and strongly divergent occlusal edges coming off the apex. The buccal side of the tooth is slightly sloped. Internally there is a broad mesial margocrista, and it seems that the lingual surface was not very concave. P l - P 2 s are quite worn; they are subequal in width b/1 and occlusally of slighdy different oudines.The P I was slighdy longer m/d buccally than lingually, but the reverse was true of P2. On PI the paracone was somewhat mesially situated but the protocone was even more so, giving a bit of a mesial twist to the lingual part of the tooth. The cusps are even more mesially positioned on P2. There appears to have been a swelling on the buccal edge distal to the paracone on both Ps. Both Ps have two relatively short and divergent roots, the buccal of which is

OLIL,

grooved longitudinally buccally and shows evidence of two root tips. M l is broken and worn. Its roots are quite short, the buccal two being quite close together and the lingual one very divergent. They separate just below the neck. M l was probably roughly rectangular in outline, though shorter m/d than b/1, and was probably smaller than M 2 . It appears that the paraconc was rather m/d short and very mesially placed. The d/b region of the much larger mctaconc was broadly rounded (thus truncating the tooth there). It appears that the hypocone sat opposite the mctacone. It was probably sited close to the mesially situated, slightly more lingually prominent protocone, making the lingual side of the tooth seem shorter m/d than the buccal side. The crown of M 2 is also incomplete. However, it was much wider b/1 and longer m/d than the Ml, although of generally the same proportions and shape and cusp disposition except in the hypocone region. The hypocone region was much larger, making the lingual side slightly longer m/d than the buccal side. The hypocone lies less far lingually than the protocone than on M l , thereby giving a slant to the inside profile of the tooth. The roots are similar in disposition to those of M l , but the lingual root is much wider m/d. The crown of M 3 is only slightly damaged. It is much smaller than M 2 and even M l , and subovoid in shape. Its enamel surface is somewhat pitted and slightly grooved. The lingual surface is more severely slanted than that of M 2 , the small somewhat centrally placed hypocone being the terminus of a thick, distally oriented postcingulum. The apex of the protocone is quite internally positioned, and the somewhat constricted, shallow trigon basin was apparently ringed by a low cresting system rather than distinct cusps. The roots of M 3 were short and disposed as in M2, but with the buccal roots being less divergent from one another. LHI. Partial RP 2 crown that is longer m/d lingually than it would have been buccally. The protocone is quite mesially placed, as the paracone would have been. The enamel is thickly wrinkled and there is a strong lingual slope. LH3f. A LP 1 crown with slightly but deeply wrinkled enamel. The quite centrally placed protocone is not as tall as the mesially situated paraconc. More markedly than on the paracone, the distal side of the protocone is noticeably longer m/d than the lingual side; it angles buccally to form a slight corner in the

GAKUS|)

189

hypocone region. In profile, there are very strong buccal and lingual slopes. The mesial edge of the paracone is distended mesially. The paracone is somewhat internally placed while the protocone is peripheral, creating a reasonably large, open V-shaped valley between them. LH3g. Part of a deeply wrinkled LP 2 crown, with the metacone region. Cf. 3f. LH6c. RP 1 , probably not fully erupted. This is an asymmetrical tooth. The region of the parastyle is swollen mesially, making the buccal side of the tooth slightly longer m/d than the lingual, and the occlusal outline trapezoidal. In buccal outline the mesial edge is longer than the distal and both terminate in thickenings, of which the mesial is more markedly developed and delineated by a crease. From the latter a thick crest runs lingually and distally following the margin of the tooth, to terminate in a small protocone that lies slightly mesial to, and well above the level of, the large paracone. The crest continues off the protocone distally and slightly lingually, to corner broadly and course along the distal side of the tooth to terminate in the small buccal thickening. A longitudinal crease separates the base of the protocone from the paracone, and connects the well-developed mesial and distal foveae. The occlusal surface is slightly wrinkled; the protocone lies more internally than the paracone. LHS (Locality 11). Two worn and damaged Ms. One, an apparent RM 2 , is very damaged, but has a strongly divergent lingual root. The other is an RM , small-crowned with a rounded distal margin. Cf. 5? LHI I (Locality 10w). Quite worn LM 2 with thickly creased enamel. The protocone is quite centrally placed and the trigon basin is constricted. The large hypocone is not d/1 swollen (thus the back of the tooth is slightly rounded), but the postcingulum is well developed. The lingual root is somewhat divergent. Cf. 5? Garusi maxilla (Tubingen, no catalog no.). Relatively small R premaxillary fragment, preserving part of the inferolateral portion of the nasal aperture and a small portion of the attendant floor of the nasal cavity; also P 1 - P 2 and the partial alveoli for I I - C . The blunt and broadly rounded preserved lateral nasal margin is confluent with a facial pillar that originallv emerged from the alveolar margin and also contained the somewhat large and long C root. Lateral to

190

SITE

this pillar, and above the region of the P I , is a fairly noticeable fossa. Internally, the very shallowly and upwardly sloping preserved part of the nasoalveolar clivus flows smoothly into the nasal cavity, continuing posteriorly for a considerable distance before beginning to curve broadly down and back (apparendy. this descent would have been quite long itself). Laterally, the surface of the nasoalveolar divus/nasal cavity floor curves moderately strongly into the smooth lateral wall of the nasal cavity. In its somewhat preserved parasagittal section the s/i tall nasoalveolar clivus is quite horizontally oriented, and the alveoli for II and especially 12 are fairly horizontal as well (suggesting that, anteriorly, the clivus was more sloping than steep). P I and P2, both apparently triple-rooted, are subequal in b/1 breadth. However, PI is much longer m/d than P2 is buccally, whereas both are subequal lingually. In occlusal outline the PI paracone, which is somewhat mesiaUy shifted, is distended mesially (apparently by a somewhat thick crest or precingulum); this distension is emphasized bv a small notch in the midline of the mesial margin of the crown. The quite mesially positioned protocone and the taller paracone are both rather peripherally placed (and are thus separated broadly, with a horizontal crease between their bases), and are partially incorporated into a thick cresting system that includes thick pre- and postparacristae, a short, buccally directed preprotocrista, and a very long, distally directed postprotocrista that corners sharply to square up the d/1 portion of the tooth before coursing directly buccally to the metastylar region. Internal to this crest lies a very m/d thin, b/1-oriented fovea. Buccally, the base of the crown is swollen. From it emerges mesially a very stout pillar that tapers as it courses to the mesial side of the paracone, and buccally there is a less pronounced and more occlusally distinguishable pillar that terminates to the distal side of the paracone. The somewhat ovoid P2 is shorter m/d buccally than lingually. The somewhat b/1 compressed paracone is rather centrally placed, while the larger and more bulbous protocone is a bit mcsially as well as peripherally placed. From it emanate thick protocristae. The preprotocrista courses directly buccally to the side of the paracone, while the thicker postprotocrista arcs gently distally, and then up to the side of the paracone. There is a horizontal crease between the bases of the paracone and protocone and internal to the protocristae. There are very faint buccal pillars near the occlusal margin on either side of the paracone.

ENTRIES

Unassignable to Morph LHlm. Partial crown of a lower I that is fit apparently narrow m/d, with a curved linc^ml surface ' LH6a. R12 that was probably not full)* erupted It is moderately tall-crowned and not very wide m/d with a fairly straight mesial edge and a flared distal edge. The lingual surface is moderately concave and the incisal edge bears a few mamelons. LH6b. LC 1 crown, probably not fully erupted with root broken off. In buccal outline this is a moderately tall crown with a fairly vertical mesial edge and a more sloping distal edge. Linsjuallv the base of the distal edge is thickened into a unguium, just behind which lies a low, broad vertical pillar. The base of the tooth is not very swollen. LH6d. Maxillary fragment with damaged Rdm2 and crowTi of P2 beneath. The latter cannot be seen directly, but evidently it was short m/d and rather wide b/1. The dm2 was subsquare, with a marked lingual slope but not markedly divergent roots. LHJO. Fragment of a L mandibular corpus with the distal root of P2 and roots of M 1 - M 2 . The corpus is broad b/1, and a large mental foramen lies high up under the root of A l l . LH13 (Locality S). Small fragment of corpus with partial roots of M l and M 3 , and both roots of M2. Corpus is not very thick b/1 and the anterior root of ramus rises below A12. LH14. All specimens with this number are worn and variably damaged. 14cr. A very compressed lower I root (probably h) with a tiny fragment of crown attached. 14b: As 14a. 14c: RIj with very worn crown. T h e root is not as wide b/1 as 14b. The crown is rather narrow m/d, with minimal lingual curvature. 14a: 1 root, probably I I . 14e: C (RC 1 ?), but appears not to be the match to 14f. The root is quite stout, straight, and somewhat compressed m/d with a deep mesial groove. The buccal surface is somewhat curved, and lingually there is a deep fissure distal to the midline that isolates a vertical pillar with a long mesial slope. The crown was probably not very tall. A female to some of the larger isolated C ! s? 14f: LC T , quite worn. The root is stout, straight and m/d compressed, with traces of a shallow mesial groove. There is a trace of cingulid mesially, and a larger cingulid distally. Lingually, a deep groove accentuates a stout lingual pillar with a

LAETOLI

(LAETOI.IL,

steep mesial slope; this is bounded mesially by a distinct margocrisrid that runs the length of the crown and defines a shallow depression distal to it. Distal to the pillar lies a thicker but vertically truncated maro-ocristid that creates a small, spikelike distal heel. Not the counterpart of 14e. 14g. Ruins of a P l t possibly L, worn and weathered. The talon id and trigonid are subequal, so the occlusal outline is not wedge-shaped (as in 14i and 4). The crown surface would have been obliquely oriented, which is also indicated by the roots. 14k: Very worn upper molar fragment. LH15. Lower R probable M 3 in matrix, worn. The rather elliptical crown is quite long m/d and not very narrow b/1; it is distended a bit d/1. It is moderately cuspulated with some cingulid on the buccal side of the protoconid. T h e apparently huge, buccally placed hypoconulid seems to have a small division lying centrally. T h e buccal cusps are somewhat internally placed, with swollen buccal sides; the lingual cusps are peripheral, more compressed and slightly taller. In this oddly shaped tooth, there appears to be a very m/d thick but b/1 short paracristid between the bases of and in front of the very mesially and only moderately large protoconid and metaconid. T h e latter, which extends more distally than the former is also slightly larger than it. The hypoconid base extends well across midline of the tooth and is delineated from the protoconid on one side and the hypoconulid on the other by a distinct groove buccally as well as occlusally. The region of the entoconid cannot be delineated in detail. LH16. An isolated M , probably R M j , worn, damaged; basically subrectangular with rounded corners. Very thick roots. LH17. L probable M 2 , worn; most of the roots are missing. It is roundedlv square, distended d/1 by a thick postcingulum and a swollen hypocone. The protocone is somewhat internally placed and there is a thick lingual cinsulum. Thick enamel, indeterminate. LH19. Isolated R M , possibly M 2 or M 3 ; damaged, roots broken. Indeterminate. LH20. L I 2 crown, identified as babooa. LH2L 26 fragments (a-z\ cranial,, posrcrariial *nd dental. T h e largest cranial pieces include 2 partial

GAKUSI)

191

R maxilla (21a, allocated to Morph 2), part of a L frontal (21 f) and part of a R posterior petrosal. There is a fragment of a deciduous molar (2 hi). The frontal fragment 2If maybe a chimera, but the part representing a L lateral supraorbital region shows a very flat posttoral surface medial to the apparent temporal line, which arises somewhat behind the orbital region. There was no supraorbital development, the frontal rising steeply off the supraorbital margin. The frontal lobe came very far forward over the orbit. The petrosal fragment 21k bears a distinct sigmoid sinus running interiorly. A shallow sulcus diverges from the sigmoid sinus and runs anteriorly across the inferior portion of the petrosal. There is no sign of a superior petrous sinus and the superior petrosal surface is essentially flat. LI122. 22a is a worn and damaged LP2, with deeply grooved buccal root, and large crown. 22b is a very worn LM 3 . Generic, thick-enamelled hominoid. LI 123. L possible M^, very worn, weathered, with broken roots. Generic thick-enameled hominoid, LH25. RP 1 or P 2 , crown worn. Very short roots, with a deep groove on the buccal root. This differs from 14i and j . If a P I , it is not as distended m/b as 14i; if a P2, it is different from the typical P2 in that the buccal surface is longer m/d than the lingual surface, and there is a swelling buccally near the root. Positions of paraconc and metaconc, and buccal thickening, arc different from what is seen in the P2of5. Ui26. RM 1 crown, very worn, Generic thick-enameled hominoid.

weathered.

REFERENCES Johan«on, D. C and T D. White. 1979. A %y\\zm*x\c **segment of early African homsnkh, Stience 202: 321-330. Leaker, M- G. et aL 200L New hrjminm %cruto (rt*m Extern Africa *hwv diverse middle PJkitene lifreargcss Nature 410:433-440, \Vhire, T. D. 1977. New (rmii hexmnuh ftf/m l^cttAtU Tanzania, AmJ. Pby-L AnttmpJ. MK Y/7-22K \Vfcj:c;T. D. 1951- Prbnsarw hovntt&fl cttsf/ne f:vmTxra*s#JL Sct&xs2l3: 343—349..

SITE

192

ENTRIES

Repository National Museums of Kenya, PO Box 40658, Nairobi, Kenya (LH specimens: clearance to view needed from Tanzania Department of Antiquities, Dar es Salaam). Institut far Ur-und Fruhgcschichte und Achacologie des

LAETOLI

Figure 1. Garusi R

ciliary fragment (scale = 1 cm).

193

L A C T O M (LAETOLDL* GAKITSI)

V

l»^

J

itftf^

H| Ah&^^^liyji

HH

1%J?^*B

ha

•••

B^^JrJB •h ;

1

LAETOU

.

Figure 1. (Continued).

-

-

194

SITE

LAETOU

ENTRIES

Figure 2. LH2, partial juvenile mandible (scales - 1 cm).

LAETOLI (LAETOLIL,

GARUSI)

195

Figure 3.1 LH3. Top L, buccal views of: Top L, LH3b, upper II; Top R, LH3c, upper 12; Bottom, LH3m, lower incisor. Top R, lingual views of: Top L, LH3c; Top R, LH3b; Bottom, LH3m. LAFTOU

•.*mm

1%

SITE

EsnrsmES

r fit

^^•J

!

\ \mt

Figure 3-2 Top row lingual vk IDW buccal views of canines,, LH3e and LH3a. LAETOU

Figure 3.4 Upper and lower premolars: Top L, LH3r, Top R LH3p; Bottom L, LH3f, Bottom R, LH31.

LAETOU

•J ^ M I

LAETOU

Figure33 Canme$ofLH3e(L)andLH3ns

Figure 3.5 LH3h, upper RM (left); LH3t, lower LM (right). (All Figure 3 scales « 1 cm).

LAETOU

LAETOLI (LAETOLIL,

LAETOLI

GARUSI)

Figure 4. LH4 partial mandible (scales — 1 cm).

197

S I T E EWTBIES

198

LAKTOU

fe^S^U?^

Figure 5. LH5 reconstructed R partial maxilla (scales == 1 cm).

LAETOU FlgUre7

- ^ H Wcanines(scale= !«»).

LAETOLI (LAETOLIL,

LAETOLI

GARUSI)

Figure 8. Lffila, partial R juvenile maxilla (scales - 1 cm).

199

L O T H AGAIN i

certainly known, but since it came from the lower portion of the Apak Member (Patterson, Behrensmeyer and Sill, 1970), its age is likely to be substantially closer to 5.5 Ma than to 5 Ma. Sec also Leakev and'Harris (2003).

LOCATION FbssiEfenxis exposures of Lothagam Hill, an isolated tanked block in die Turkana Basin, between the Kerio and Lomunvenkupurat rivers and just west of the southwestern shore of Lake Turkana in northern Kenya (Map 2). DISCOVERY A. D. Lewis, 1967, on a Harvard expedition led by Bryan Patterson. MATERIAL R mandibular corpus fragment with very worn M l and roots of M2—A13.

DATING AND STRATIGRAPHIC CONTEXT The Lothagam stratigraphic sequence overlies Miocene volcanics (Patterson, Behrensmeyer and Sill, 1970). It consists of several fossiliferous levels, most recendy studied by Leakey et al. (1996), who consider the quality of radiometric dates so far derived to be relatively poor. The lower fossiliferous levels of Lothagam Hill are now grouped into the Nawata Formation, spanning from about 8 to 5.5 Ma, with younger exposures attributed to the Apak Member of the lower Nachukui Formation continuing above to about 4.7 Ma (Leakey et al., 1996). The Nawata/Apak boundary seems to have witnessed a substantial fauna turnover (Leakey et al., 1996). The age of the hominid mandibular fragment is not

PREVIOUS DESCRIPTIONS AND ANALYSES The mandibular fragment KNM-UT 329 is one of only three hominoid specimens known from Lothagam (the other two are isolated teeth from die upper member of the Nawata Formation), and given its incompleteness and the extreme wear on die preserved tooth, many nowadays are more comfortable referring to it simply as tt hominoidw rather than as "hominid." It was listed as Australopithecus cf. africamts by Patterson, Behrensmeyer and Sill (1970), an attribution quoted by Howell (1978) in his authoritative review of African mammalian faunas. However, it has never been subjected to definitive scrutiny, and most paleoandiroplogists would probably informally consider it Australopithecus sp. indct.

MORPHOLOGY

KNM-LT 329. Fragment of R mandibular corpus containing very worn M l , roots of M2 and mesial roots of M3. Orienting M l occlusally, the inferior margin of the corpus rises steeply posteriorly. The inferior part of the corpus also thins b/l in the same direction. The mandible was probably not very deep s/i under Ml; at the alveolar margin it was quite broad. A moderately large mental foramen lies under the septum between

200

LOT

P2 and M l . The anterior root of the ramus takes origin on the distal side of M 2 . Internally, a low mylohyoid line began under M 3 ; inferior to it is a very large, deep submandibular fossa. T h e M 2 was probably larger b/1 and m/d than the M l . T h e IV13 is wider b/1 mesially than M l , a n d probably tapered distally. T h e M l is extremely worn, weathered; it is roundedly square and apparently had a small, centrally placed hypoconulid.

ii Ad AM

201

Leakey, M. G. ct al. 1996. Lothagam: A record of faunal change in the late Miocene of East Africa. Jour. Vert. Paleontol. 16:556-570. Patterson, B., A. K. Bchrcnsmcycr and W. D. Sill. 1970. Geology and fauna of a new Pliocene locality in Northwestern Kenya. Nature 226: 918-921. Sec also: Leakey, M. G. and J. M. Harris. 2003. Lothagam: The Dawn of Humanity in East Africa. New York: Columbia University Press.

REFERENCES Howell, F. C. 1978. Hominidac. In: V. J. Maglio and II. B. S. Cooke (cds), Evolution of African Mammah. Cambridge, MA: I Iarvard University Press, pp. 154-248.

LOTHAGAM

Repository National Museums of Kenya, PO Box 40658, Nairobi, Kenya.

Figure 1. K N M - L T 329. Partial R mandibular corpus (scales = 1 cm).

LUKEINO

sediments accumulated between 6.0 and 5.7 Ma, and at about the same time Deino et al. (2002) published Ar/Ar determinations constraining Lukeino deposition to between 5.88 and 5.72 Ma. The four hominid localities are scattered throughout the sequence: Cheboit and Aragai are near the bottom; Kapsomin (the type locality of O. tugenensis) is in the lower middle; and Kapchberek is toward the top. The associated fauna is consistent with an age of just under 6 Ma for the Lukeino hominids.

LOCATION The localities of Chcboit, Kapchebcrek, Aragai and Kapsomin in the eastern foothills of the Tugen Hills, west of Lake Baringo, Kenya (Map 2). DISCOVERY The first hominid molar from a Lukeino locality (Chcboit) was collected in 1974 by K. Cheboi, on an expedition directed by M . Pickford. Further specimens were recovered by the Kenya Palaeontology Expedition in 2000.

PREVIOUS DESCRIPTIONS AND ANALYSES T h e 1974 molar was reported by Pickford (1975) as "Hominidae indet." Following the discover}' of the additional material in 2000, Senut et al. (2001) referred the Lukeino hominids to the new hominid genus and species Orrorin tugenensis. Senut et al. argued that the preserved femoral fragments indicated bipedalit}' on the ground, while the humerus and manual phalanx suggested some degree of arboreal adaptation. They proposed a phylogeny in which Ardipithecus was sidelined to an ancestor ot the African apes, and in which the australopithecines represented a terminal development that had diverged from the hominid main line prior to Orrorin. They envisaged their new taxon, with its small, thickenamelled molars and somewhat **apc-likc" lower posterior premolar, as being ultimately ancestral to Homo. Pickford et al. (2002) reaffirmed the presence ot a suite ot' bipedal characters in a series of femoral fragments ot Orrorin, all shared with australopiths and

MATERIAL In addition to the 1974 molar tooth (KNM-LU 335), Senut et al. (2001) reported 11 new numbered Lukeino hominids, including four isolated teeth, two mandibular fragments (BAR 1000'OOa and BAR 1000\)0b) and various postcranials. The mandibular fragments form the holotype of the species Orrorin tugt'ntmh% and the remainder of the listed specimens are assigned as paratypes (Senut et al., 2001). DATING AND STRATIGRAPHIC CONTEXT i he late Miocene Lukeino Formation consists of over 130 m ot tluviolacustrine sediments overlving a weathered volcanic surface dated to 6.2 Ma (Pickford and Senut, 2001). They are overlain by basalts of the Kaparaitu Formation dated to 5.65 Ma (Pickford and Senut, 2001). On the basis of new K/Ar determinations Saw-ada et al. (2002) concluded that the Lukeino

202

IIJII

III • • ! • • •

• I

ISHBHH^BM

L t* K e i s o Homo, but none with Pan or Gorilla; within the hom inid group, they discerned closer resemblance to modern humans than to australopiths. MORPHOLOGY In the small published sample of mandibular and dental fossils from Lukcino sites allocated to Orrorin tuptnensisy more than one dental morph seems to be represented. Published specimens arc individually described below, within morphs. BAR lOOO'OOa Morph (includes BAR 1000'OOb) BAR WOO'OOa. L mandible fragment containing vcrv damaged M 2 - M 3 , plus part of the root of M l and the base of the anterior margin of the ramus. The inferior margin of the mandible is preserved mostly below the region of M 3 , suggesting that although the mandible was small overall, it would have been deep relative to crown height. External surface of the bone is smooth; a swelling emerges below the posterior portion of M l and continues up and back into the anterior border of the ramus, which seen from the side would have obscured only the most distal portion of M3. The anterior portion of the ascending ramus would have been quite vertical. There is only a very small mandibular gutter buccal to the M 3 . In cross section the mandible is relatively straight buccally, whereas lingually the surface is concave inferiorly, producing a very thin inferior portion. There is no evidence of a mylohyoid line or a submandibular depression, or of any development of an internal alveolar crest. The ramus would probably have thinned posteriorly. The preserved distal root of the M l shows two closely approximated root canals. T h e root itself is single at this level, is compressed b/1, and is slightly arced in the exposed cross section, so was probably concave mesially. The closeness of the roots suggests that the crown of the M l was smaller than that of the M2 and even the M 3 . Mesial to this root, low down, is a portion of the anterior root. Both the M 2 and the M3 are missing significant sections of enamel. T h e preserved occlusal regions appear to have been somewhat worn. Even so, exposed cross sections of enamel appear to have been moderately thick. Apparently both molars were similar in length, but the M 3 was narrower b/1. From what is preserved, it appears that on both molars the mctaconid and protoconid were opposite each other and lay quite far forward on the

203

tooth. On both molars there is a deep fissure running to the distal side of the protoconid, from the buccal side to the midpoint of the talonid basin. On M2 it appears that the protoconid and mctaconid are closely appressed, creating a scmicristid-like structure between them. Behind it another cristid-like structure is preserved, running from the protoconid toward the mctaconid distal to the first scmicristid, creating a small basin between them. On M2 it appears that the hypoconid was huge (the largest cusp), and wedgeshaped, with a m/d long base that does not cross the midline of the crown. The hypoconulid appears to have been very large by any standard. It appears to have been wedge-shaped, with its pointed apex in the midline of the tooth. What is preserved of the base of the cntoconid suggests that this cusp was somewhat b/1 compressed, but quite m/d long, as well as somewhat internally placed, in contrast to the hypoconid, which is quite buccally placed. The talonid basin is very short m/d between the apex of the hypoconulid and the distal cristid of the mctaconid, and is wide b/1 over the broad, flat surface of the hypoconid. It is probable that M2 was relatively straight across the mesial surface, and shallowly but broadly rounded distally. O n M 2 - M 3 it appears that the distal surface of the metaconid was quite vertical and faced somewhat back and buccally. It also appears that on both teeth the protoconid was taller than the metaconid. Like M 2 , M 3 appears to have been relatively straight across the mesial surface, and was probably rounded posteriorly. In contrast to M2, the metaconid on M3 is noticeably longer m/d than the protoconid. A paracristid courses straight down from the apex of the protoconid to the middle of the base of the metaconid; this also appears to have been the case on M2. On M 3 the cntoconid was very small, and delineated distally by a wide, somewhat shallow notch from what may have been a large, wedge-shaped, centrally placed hypoconulid. The hypoconid is huge (again the largest cusp), being very long m/d and with a somewhat blunted base that crosses the midline of the crown to make equal contact with the mctaconid and cntoconid. T h e talonid basin appears to have been very truncated by the base of the hypoconulid extending into it, almost like a centroconid. Its occlusal surface also bears a moderately deep groove that creates two crest-like structures. On M 2 - M 3 the buccal sides arc bulbous low down. On M 3 , as preserved on the distal surface of the protoconid, the enamel is softly wrinkled.

/ * *^ v

/

204

SITE

BAR 1000'OOb. Very small fragment of R mandibular corpus containing a small and somewhat damaged and weathered A13. Plausibly from the same individual as 1000'OOa. From what is preserved the corpus would not have been very robust. The mesial part of the tooth is missing, as is most of the region of the hypoconulid. The distal parts of the protoconid and metaconid arc preserved, and lie opposite each other; a groove running from the buccal side of the tooth into the talonid basin delineates the distal side of the protoconid. There appears to be a twinned cristid-like structure (as on the M2 of 1000'OOa) running lingually from the protoconid toward the metaconid; the latter cusp is somewhat longer m/d than the former. The internal surface of the metaconid appears quite vertical, and this cusp may have been substantially taller than the protoconid. T h e somewhat centrally placed hypoconulid is very small and compressed m/d. Its base extends as a cristid into the very truncated talonid basin. Distally the hypoconid is separated from what is preserved of the hypoconulid by a wide, shallow groove. T h e hypoconid appears to have been rather large and wedge-shaped; its base crosses the midline of the crown to make equal contact with the metaconid and entoconid. The moderately large, m/d long and somewhat b/1 compressed entoconid is somewhat peripherally placed, and lies somewhat mesially right behind the metaconid. A cristid extends down the internal surface, running mesially into the talonid basin. W h a t is preserved of a long, moderately deep, d/b-oriented and somewhat m/d compressed basin separates the entoconid from the hypoconulid. T h e buccal side of the tooth is somewhat bulbous, whereas the mesial side would have been fairly straight, and the distal side rather curved.

BAR 1426*00 Morph BAR 1426'00. This is a molar tooth with some bone adherent. Weathered and moderately worn, in occlusal outline a rounded isosceles triangle. T h e occlusal surface is quite flat, with little cusp delineation. If this tooth is a lower R M 3 , the two most prominent cusplike structures are the very mesially and lingually placed metaconid and the d/1 and peripherally placed hypoconulid. W h a t corresponds to the protoconid is very low and somewhat peripherally placed. The lingual part of the m/b surface of the tooth is

ISNTuIKN

somewhat vertical, whereas the rcinon mrci-,11,,. t i c *\ •1 . c s , a l J ) around the base ol the metaconid and mesial t hypoconid is strongly inclined inward. It appear* .1'° on portions of the perimeter of the tooth there %"' numerous vertical grooves, and that the occlusal s face was probably somewhat wrinkled. Under the gion of the hypoconulid lies an almost complete sin'l and somewhat rounded root. Typically for a lower M it appears that a somewhat b/1 broad and m/d compressed root lay under the mesial portion of the tooth If this is, instead, an upper M (as it would have to be if associated with the specimens above), then it is an upper L M 3 that is distended buccally in the rceion of the paraconc, with a low, broad and indistinct protoconc opposite. There is no distinct mctacone, but what appears to be a very thick postcingulum runs distally from the paracone and arcs down and forward to the protocone. The lingual surface of the protocone is quite sloping, as is the surface of the tooth just distal to the paracone. It appears there were grooves in places around the perimeter of the tooth. There is a mostly complete root above the paracone, and the buccal surface of another root distal to it. The mesial side of the tooth is much wider b/1 than the distal, yielding a somewhat roundedly triangular tooth. There probably was a beaded postcingulum. In sum, this is a flat tooth with little cusp delineation. Even if it is an upper molar, it is an unlikely match for the teeth just described, with their complex occlusal morphologies.

Unassignable to M o r p h BAR 100J W. Remnants of a huge upper LI1. The buccal sides of the preserved root and crown are somewhat flat across, and what is preserved of the lingual surface is also somewhat flat and quite sloping toward the now-missing incisal edge. The root is quite stout, and in cross section is roundedly triangular. 1 he apex lies lingually.

REFERENCES Deino, A. L. et al. 2002. ^Ar/^Ar gcochronology and paleomagnctic stratigraphy of the Lukcino and lower Chcmeron Formations at Tabarin and Kapchcbcrck, Tugcn Hills, Kenya./ Hum. Evol 42: 117-140. Pickford, M. 1975. Late Miocene sediments and fossils trom the Northern Kenya Rift Valley. Nature 256: 279-2S4.

L U K K INO

• J M. and B. Scnut. 2001. The geological and faunal picW° ''nnc Miocene hominid remains from Lukcino, K UlCSl '° r R *AcU Sci Paris 332: 145-152.

Scnut, B. ct al. 2001. First hominid from the Miocene (Lukcino Formation, Kcnva). C. R. Acad Sci. Paris 332: 137-144.

Ivcrt^""**-

• j M ct al. 2002. Bipcdalism in Orrorin tugenemis led by its femora. C. R. Palcovol. 1:191-203. . g c t aJ. 2002. The age of Orrorin tugcnemis% an SiW f. hominid from the Tugcn I Iills, Kenya. C. R.

£ U 1:293-303.

205

Repository Community Museums of Kenya, PO Box 74689, Nairobi, Kenya.

*•»*&•&

.w*

w^is^&spf

LUKEINO

Figure 1. CiMK BAR lOOO'OO

a, partial L mandibular corpus (scales = 1 cm).

^

206

SITE

LUKEINO

ENTRIES

Figure 2. CMK BAR 1000'OOb, partial R mandibular corpugiscal^l cm).

LUKEINO

LUKEINO

Figure 3. CMK BAR lOOl'OO, upper LIl (scale == 1 cm).

207

208

SITE

LUKEINO

Figure3.

{Continued).

ENTRIES

Figure 4. CMK BAR 1426'00, molariform (scale = 1 cm). LUKEINO

MAKA

LOCATION Collecting area to the east of the Awash River in the Middle Awash Valley of Ethiopia, south of Hadar. Adjacent to Belohdelie (Map 1).

PREVIOUS DESCRIPTIONS AND ANALYSES The initial proximal femur from Maka was closely compared by White (19S4) to similar specimens from Hadar assigned to Australopithecus afarcmh. Further mandibular and other rinds from Maka were confidently referred to this species by White ct al. (1993). A more elaborate description of the Maka hominid assemblage was made by White ct al. (2000), who found the MAK-VP-1/12 adult mandible to be "an excellent match* for its Hadar and Laetoli counterparts. They further added that the A. afartmh mandibular sample as enlarged by Maka seemed to form part of a steadily molarizing lineage leading from ArJipithccus nwiufus, through A, <;w<;w/mw, to this form and eventually to the robust australopiths. This notion has yet to be commented on.

DISCOVERY Initial hominid discovery (a proximal femur) was made in 1981 by a team under the direction of J. D. Clark; further specimens, including the mandibles, followed in 1990.

MATERIAL One fairly complete mandible, several mandibular fragments, a tiny cranial fragment, a few isolated , teeth, and postcranials that are fragmentary except for most of a large humerus and a proximal femur.

Mown IOLOGY The sample consists of one fairly complete jaw (MAIv VP-1/12); one ramus (VP-1/S3); one R posterior corpus with partial ramus (VIM/2); a L posterior fragment of corpus (VP-1/6); a tiny cranial fragment (VP-1/5); a RMA crown (VP-1/4); and a fragment of an LdmJ (VP-1/13), identified originally as a U P . Also some fragmentary postcranials. In general, mandibles and teeth with preserved morphology appear to be similar in comparable pans, with some variation (e.g., increasing rise of the inferior margin ot the corpus posteriorly; absence of mylohyoid line and submandibular fossa; some obscuring ot Mi by anterior margin of ramus; number of posterior marginal

DATING AND STRATIGRAM nc CONTEXT The mostly fluviatilc Maka deposits conformably overlie the long Middle Awash sequence of Pliocene strata laid down principally in a sequence of large lakes (White ct al., 1993) between about 5.7 and 3.9 Ma and recently assigned to the Miocene-Pliocene Sagantolc Formation by ftenne ct al. (1999). Ar/Ar dates on a marker tuff (the SI IT) just above the upper boundary of the Sagantolc Fm tie the Maka hominids fairly tightly to about 3.4 Ma, an age in good agreement with the fauna (White ct al., 1993; Renne ct al., 1999).

209

210

SITE

thickenings on ramus internally; orientation of and more pronounced medial projection of condyle; lateral termination of sigmoid notch crest; developed trigonid basin on lower molars; notch between hypoconulid and hypoconid and hypoconid and protoconid). Given the small sample size, specimens will be described individually. MAK-VTM/2 Lower Dental Morph (includes VP-1/6) MAK-VP-I/2. Consists of a partial R corpus from M l posteriorly, and parts of the ramus (coronoid process and most of gonial region are missing). Heavily reconstructed. All M s very worn, weathered. The gradually rising inferior margin suggests that the corpus would have been deeper anteriorly than posteriorly. The front of the corpus would have been fairly deep s/i, but probably was not very wide m/1 for most of its length (it thickens only distal to M l ) . The bone thins somewhat infcriorly. The anterior root of the ramus begins to become distinct only behind M 2 , where it curves steeply up, obscuring the distal half of M 3 . The mandibular gutter is fairly wide and probably flowed into a shallow depression above it. The ramus is very a/p long and thins markedly posteriorly. In front of the gonial region, the preserved inferior margin bears a thickened muscle scar. The preserved posterior margin of the ramus bears a thickening that was probably continuous anteriorly around the gonial region; thickening is also detectable just anterior to the the midline of the ramus, where it fades out. T h e posterior margin of the ramus (like the anterior margin) is quite vertical. The neck of the condyle inclines backwards; a roughly triangular and downwardly tapering bony surface lies posteriorly on it. The condyle is quite distended medially and is somewhat compressed a/p; its long axis is slightly obliquely oriented (i.e., medial aspect is more posterior than the lateral). It was wide m/1 and was probably more truncated laterally. The sigmoid notch crest was positioned rather laterally. Internally there is no evidence of a mylohyoid line, submandibular fossa, or internal alveolar crest. On the posterior margin of the ramus, and level with the occlusal surface of M3, part of a distinct tuberosity is preserved. Teeth. Worn M 1 - M 3 are preserved. They increase in m/d length M 1 - M 3 . M l is markedly shorter m/d than M2, which is somewhat shorter m/d than M3. M l was probably slightly narrower b/1 than

E NT KIE S

M 2 - M 3 , which appear to be of similar b/1 width \\\ is quite rounded distally, as appears to be the case f M 1 - M 2 . The d/I corners of M 1 - M 2 were apparently slightly truncated. O n all three molars, the buccal and lingual cusps lay opposite each other. Grooves on the occlusal surface of M l suggest that the fo primary cusps were subequal in size. There probably was a hypoconulid that straddled the midline of the crown. On M2 the protoconid and mctaconid were much smaller than the distal pair of cusps. A slight distal swelling that lies lingual to the midline of the crown must represent that extremity of the hypoconulid. The M 3 protoconid and mctaconid arc subequal in size and slightly larger than the subequal hypoconid and entoconid. There appears to have been a moderately m/d long paracristid that was thickest as it emerged from the protoconid and thinned as it coursed in front of the mctaconid. There is a slight swelling at the lingual extent of the mctaconid base, which is delineated from the entoconid by a modest notch. A more marked groove or notch separates the entoconid from the very lingual extent of the very b/1 wide and generally large hypoconulid that occupies the entire distal part of crown. MAK'VP'l/6. A crushed, weathered fragment of a corpus with the roots of M 2 - M 3 . The corpus is quite shallow s/i and thin m/1. The bone tapers strongly inferiorly. T h e M 2 mesial roots are strongly bifid at their tips; the distal root was large, probably single. M 2 was probably shorter m/d than M 3 , which was probably similarly rooted. The M 3 was probably narrow b/1 and tapered distally.The m/d length of the M 3 relative to the apparent length of the M2 is similar to VP-1/2. MAK-VP-1/12 Lower Dental Morph (includes MAK-VP-1/4) MAK-VP-1/12. Damaged and weathered mandible, missing the R and L coronoid processes and gonial angles and part of the R and L condyles. L12-RC alveoli are preserved; all other teeth arc present but quite worn. The corpus is not very deep s/i. It is only moderately wide m/1, with tight parallel inner and outer curves at the front. The cheek tooth rows are straight until the M3s, which arc oriented slightly outward; externally, the corpora are more divergent. The interior margin rises slightly posteriorly. Externally, as better preserved on the R, the bone below the I I - ^

MAKA

roots is slightly depressed (which creates a hint of a low midline bulge near the alveolar margin). More infcriorly, the bone is smoothly and tightly curved from side to side. In lateral profile, it appears that the alveolar region may have projected slightly forward, in accordance with the curvature of the 11-12 roots. Below, the mandible descends gently and smoothlv back and down; it then curves back into the inferior margin, which is slightly elevated near the midline. A moderately large mental foramen lies well below the R and L P 1 - P 2 . The bone above and slightly posterior to this foramen is broadly but very shallowly excavated. The anterior root of the ramus arises below Ml bilaterally, midway down the corpus. It quickly swells out posteriorly to reach its maximum thickness level with M 1 - M 2 ; the bone behind thins quite rapidly. In side view, as preserved more fully on the R, the anterior margin of the ramus curves steeply up distal to M2, almost totally obscuring M 3 . There is a relatively wide mandibular gutter on both sides; as preserved on the R, it continues superiorly into a deep excavation on the inside of the ramus. This excavation is bounded posteromedially by a stout crest that arcs down from the coronoid region to fade out behind M3. The preserved parts of the gonial surface generally lack muscle scarring, but there is some thickening of the inferior margin preserved on the R. Both condyles are broken; they were clearly wide m/1 and thinner laterally, becoming wider and more rounded medially (as viewed from above). Also as seen from above, the long axis of each condyle is oblique (the medial portion lies well posterior to the lateral). Seen from behind, the better preserved R condyle tapers strongly inwards, yielding a triangular posterior surface. Both sigmoid notch crests run to the base of the lateral margins of the condyles. As suggested on the R, this notch is neither very long a/p nor very deep s/i relative to condylar height. Internally the postincisal plane is long; it slopes fairly gently down and back, then about halfway down the corpus it drops vertically into what was probably a deep genial fossa containing subsidiary depressions. Below, a very strong vertical crest lies in the midline, fading out before reaching the inferior margin. Neither a mylohyoid line nor an internal alveolar crest is discernible. O n both sides, and slightly posterior to the genial fossa, lies a shallow but not very long submandibular fossa. Digastric fossae cannot be identified. On the R, and almost level with occlusal surface of M 3 , is part of the inferior margin of what

211

would have been an upwardly and backwardly facing mandibular foramen. The internal gonial region above and behind M3 is thin-boned (and thus appears excavated). Teeth. Alveoli indicate that the 11-12 roots were subequal in size, quite compressed m/d, but wide b/1. Although worn, LI2 is still fairly high crowned and moderately spatulate in oudine, flaring somewhat laterally. Its buccal surface is fairly vertical; the lingual surface is relatively smooth and slopes steeply backward. The U2 root looks stout relative to the crown. The C root is only moderately stout and not very long; it is ovoid in cross section. The C crown would have had a distinctly projecting, slightly recurved tip, with a very short, probably quite horizontal, mesial edge. Its distal edge is long and steeply curved down to a small d/b heel. The lingual surface is mildly rounded but essentially featureless. The Pis (as preserved better on the R) are not as wide b/1 as P2, but they are at least as long m/d. As seen on the R, PI has two moderately widely splayed buccal roots that diverge not far below the neck. The mesial root is antero-obliquely oriented (as is the crown). The m/b portion of the P i crown is slightly swollen over the root. O n both sides, a short paracristid runs m/1 from the protoconid, turning down strongly at the crown's midline to enclose a very small, moderately deep, tall and lingually facing fovea between it and the metaconid. As preserved on the R, the strongly distolingually oriented inferior margin of the anterior tovea bears a small stylid-like swelling; otherwise the fovea is totally open. On the R, the PI metaconid lies opposite, at the same height as, and barely separated from, the somewhat mesially positioned protoconid. On the L, if there was a definable metaconid (that region is broken lingually), it was separated from, and markedly lower than, the mesially placed protoconid, which it lies opposite. A thin but distinct crest runs directly down the internal face of the protoconid. On the RP1, a thick cristid courses directly back from the protoconid, turns straight in lingually and then curves up to the metaconid, enclosing a relatively large, and probably moderately deep, distal fovea. The outline of this PI is thus broad distally with a strong m/b taper. On the L P 1 , a somewhat developed cristid courses distolinguallv down from the protoconid and probably turned toward the metaconid region from the d/1 corner of the tooth. The distal fovea thus is more vertical and lingually facing on the LP1, and b/1 broader and distally facing on the RP1.

212

StTK E N'T K IKS

O n both P2s the protoconids are worn much lower than the metaconids opposite them. 1 he bases of these two mesiallv placed cusps meld high up. O n both, the buccal side of the crown is wider h/l mesiallv than distallv. A small fovea lies anterior to the junction of the protoconid and metaconid bases; a thick cristid ran distallv and slightly lingually from protoconid* turned straight lingually along the distal edge and then turned mesiallv at the d/1 corner to course to the metaconid; the cristid encloses what was probably a moderately sized distal fovea. T h e molars are quite worn, especially the M i s . These teeth increase in m/d length from M l to M 3 ; M l is noticeably the shortest* with less disparity in length between M2 and M 3 . M l is b/l narrower than the subequally b/l wide M 2 - M 3 . In all M s , the protoconid and metaconid lie opposite each other, and these cusps are larger than the hypoconid and entoconid, which also lie opposite one another. T h e distal side of M 3 , and probably also of M 1 - M 2 , is somewhat rounded, but on M 1 - M 2 (especially on the R) there is a distal swelling lingual to the midline or the tooth that most likely represents the hypoconulid. There may have been a fovea lingual to this "swelling/cusp" on M 1 - M 2 . T h e M 3 hypoconulid is relatively small; it lies quite buccally and is separated from the hvpoconid by a small notch and connected to the cntoconid by a thick postcingulid that encloses a relatively large and deep posterior fovea. As better seen on the L, there is a well-defined hvpoflexid notch between the protoconid and hvpoconid on M l ; this notch is narrower m/d on M 2 - M 3 . The M3s have an m/d thin, but relatively b/l wide, trigonid basin. T h e buccal sides of the M3s are swollen. MAK-VP-1/4. A RM 3 crown missing its roots. This tooth is relatively long m/d, moderately wide b/l and is quite narrowly rounded distallv. The buccal side is strongly sloping and the buccal cusps arc somewhat centrally placed, thus constricting an m/d long and moderately thickly crenulated talonid basin. The hypoconulid is of moderate size, centrally placed and subdivided along its midline. There is a deep notch between it and the hypoconid, and another between the hypoconid and protoconid. The metaconid has a short buccal cingulid on its base distallv. A deep, very b/l wide and moderately m/d long trigonid basin runs across the front of the crown. The hypoconid is the smallest of the main cusps.

Unassignable to Morph MAKA'P-1/13. Broken* Broke very weathered and w 0 \t,\KW*!/lX J Ldm , which was roundedly subsuuare. The n conid is more distended lingually than the roiuuM hvpocone region; its apex was probably ccntrallv placed. The trigon basin is small and was confuted between the protocone and metacone. MAK-VP*l/\ An uninformative cranial fragmentit is relatively thin boned, with many narrow grooves for meningeal arteries. MAKA'P-l/SJ. Upper part of a L mandibular ramus, partially damaged and reconstructed, missinc the lateralmost part of the condyle. The preserved portion is quite long a/p, with fairly vertical anterior and posterior margins. The coronoid process would have been bluntly rounded, and minimally taller than the condyle. The sigmoid notch is moderately long a/p, deep and smoothly arced; its deepest point lies at the midpoint of the notch. T h e sigmoid notch crest would have faded out at the base of the lateral part of the condyle. The medial portion of the condyle is projecting; the lateral portion did not project far. The condyle is somewhat compressed a/p; its axis is directly transverse. Posteriorly the condylar neck has a triangular, downwardly tapering surface. A series of three faint swellings lies internally along the posterior margin of the ramus, below the neck. Running forward and down from the medial aspect of the condyle is a thickening that becomes more prominent and strutlike interiorly. More medially, this stmt is joined by a low swelling that rises far down below the coronoid process. Above where they converge, the bone is excavated. The mandibular foramen is large and superoposteriorly pointing; it lies on the posterior aspect ot this strut.! he mylohyoid groove runs down from the posterior margin of the foramen. There was apparently no lingula.

REFERENCES Rcnnc, P. R. ct al. 1999, Chronostratigraphy of the MiocenePliocene Sagantolc Formation, Middle Awash Valley, Atar rift, Ethiopia. Geo/. Soc.Am. Bull. I l l : 869-8S5. White, T. D. 19S4. Pliocene hominids from the Middle Awash, Ethiopia. Cour. Forsck Inst. Senckenberg 69: 57-68. White, T. D. et al. 1993. New discoveries of Australopithecus at Maka in Ethiopia. Science 366: 261-265.

MAKA

White, T. D. et al. 2000. Jaws and teeth of Australopithecus afarensis from Maka, Middle Awash, Ethiopia. Am. J. Pbys. Anthropol. 111:45 - 68.

MAKA

213

Repository National Museum of Ethiopia, PO Box 79, Addis Ababa, Ethiopia.

Figure 1. N M E M A K VP 1/2, R partial mandible (scales = 1 cm).

t

S i t e ErNTRFES

214

MAKA

Figure 1.

(Continued),

MAKA

215

1" I - I I •

wmM I MAKA

Figure 2. NME MAK VP 1/4, lower R molar (scale = 1 cm).

SITE ENTRIES

216

MAKA

Figure 3. NME MAK VP 1/12, partial mandible (scales = 1 cm).

M.&HL&

MAKA

Figure 3.

(Continued),

217

SITE. ENTRIES

>1«

18

MAKA

Figure 4. NME MAKVPV83, partial L mandibular ramus (scales = 1 cm).

MAKAPANSGAT

LOCATION Makapansgat Limcworks: cave breccia deposit exposed 16 km ENE of Potgietersrust, Northern Province, South Africa (Map 4). DISCOVERY Site mined for lime between 1925 and 1935, in the process producing a fossil mammal fauna. First hominid found by J. Kitching, September 1947, during a survey directed by R. A. Dart. Subsequent hominid finds were made through 1963 in excavations directed by A. R. Hughes, and investigations have recently resumed. MATERIAL Some 45 numbered hominid fossils, including mandibles, partial crania and postcranial elements. DATING AND STRATIGRAPHIC CONTEXT The Makapansgat Limeworks Deposit consists of brecciated infill in a large cavity in Precambrian dolomites. As in all such cases, the cave has had a complicated history of filling and erosion. Some hominids were discovered in situ in the breccia, although most were recovered from rubble in the miners' dumps. Five Members have been recognized in the breccias, corresponding to five cycles of deposition (Partridge, 1979), although it has been argued that this division obscures a greater complexity of events (Maguire, 1985). All but three of the hominids derive

from Member 3 (the "Grey Breccia"). The exceptions come from Member 4 (the "Pink Breccia"), and include the partial cranium MLD 37/38. Attempts to date the deposits chronomctrically are still in the experimental stage (see below), and generally accepted age estimates still depend on faunal comparisons. Vrba (1985) found Member 3 to be the "oldest hominid associated assemblage in South Africa, and close to, and perhaps a little later than, 3 million years in age" (p. 195). This agrees well with the detailed faunal seriations of McKce, Thackeray and Bcrger (1995), who placed both Makapansgat Members 3 and 4 as the (then) oldest australopith-yiclding deposits of South Africa. Consensus thus currently places the Makapansgat hominids approximately between 3.0 Ma (or perhaps a little more), and 2.6 Ma. A recent paleomagnctic study has placed the Grey Breccia as spanning the period between about 4.0 and 2.0 Ma (Herries and Latham, 2002), but Blackwell et al. (2001) propose on the basis of ESR dating of alcelaphine tooth enamel that Member 3 might possibly date to as little as 2.0 Ma. ARCHAEOLOGICAL CONTEXT None. Raymond Dart (1955) reported a "pebble culture" from Makapansgat, and later based his notion of an "osteodontokeratic" culture on his belief that the Makapansgat australopiths were responsible for the bone accumulations there (Dart, 1957; see also Dart, 1925); but these notions were rapidly discarded, as was the idea that the early hominids had used fire

219

220

SITE ENTRIES

(hence the name Australopithecus prometheur. Dart, 1948a). PREVIOUS DESCRIPTIONS AND ANALYSES In 1948, Raymond Dart (1948a) made the first partial cranium from Makapansgat the holotype of the new species Australopithecus prometheus. Over the next decade and a half, as Alun Hughes and his team continued to labor at the site, there followed a stream of descriptions of new Makapansgat fossils assigned to this species (e.g., Dart 1948b, 1949a, 1949b, 1949c, 1954, 1959a, 1959b, 1962a, 1962b). Throughout this period. Dart continued to assign his Makapansgat hominids to A. prometheus, but by the mid-1960s a consensus had emerged that the Makapansgat australopiths were more properly assigned to the species Australopithecus africanus, known also from Taung and Sterkfontein (see Day, 1965). This continues to be accepted wisdom today, as illustrated by the recent assignment by Reed et al. (1993) of a proximal femur from Makapansgat Member 4 to A. africanus. Holloway (2000) reports a brain volume of 435 ml for the cranium M L D 37/38, and an estimate of 500-520 ml for M L D 1. MORPHOLOGY Morph association is especially difficult at Makapansgat because of the variety of unconnected cranial, mandibular and dental regions represented. Thus, for example, the cranial base of M L D 37/38 matches with that of the Sterkfontein specimen Sts 5, but the latter lacks a dentition to associate it with dental specimens. However, the configuration of the snout in Sts 5 appears to be sufficiently different from that of this region in specimens from Makapansgat such as M L D 9 to preclude ready association. Further, the preserved facial and dental structures of specimens such as M L D 9 appear a great deal more similar to what is seen in the Kromdraai specimen T M 1517a. To complicate the picture, the lower dm2 M L D 5 possesses the twinned trigonid basin that is so characteristic in the Taung-type specimen of Australopithecus africanus. And in turn, the lower M l of Taung differs morphologically from the specimens composing the M L D 2 morph, as well as those specimens, such as M L D 4, whose lower molar morphoplogy more closely matches that of the Kromdraai specimen T M 1517b. Finally, two isolated teeth from Makapansgat, one lower and one upper, appear to match Sterkfontein

specimens belonging to the St\\ 2:>2 rooroh A~»is impossible ncre to associate upper ir.d kr.trr A*~ tognathic morphs. T M 1517a Facial Morph (includes M L D 6,9,12,451 and Upper Dental Morph (includes M L D 11, p 23 28,30,41,44) MLD 6. R lower face with "snoutv* appearance. Maxilla contains alveolus tor C, broken Pi, 2rtd P 2 - M 2 , plus part of root of M 3 . Small individual, goes with M L D 23. The orbit was probably tall and ovoid. Intcrorbital space was probably tall but not wide. Nasal bones were long and not wide, though broadening inferiorlv. Nasion lay well above the frontomaxillary sutures. In profile the nasal region is slightly concave and nasion would have lain in the somewhat projecting glabellar region. Interiorly, the nasals are moderately flat across, with a barely detectable central keel. On the R the posterior lacrimal crest is low and lies in the orbit directly behind the anterior lacrimal crest. The infraorbital nerve probably turned inferiorlv well behind the inferior margin of the orbit, and its groove may not have been roofed with bone. The nasal aperture was small and upwardly tapering. Its lateral rim is quite sharp superiorly, but becomes more rounded toward its smoothly rounded inferolateral corner. The clivus makes a smooth transition into the nasal cavity. The inferior nasal margin slopes slightly up toward the midline, where there is a distinct step down to the incisive fossae behind possible anterior nasal spines. There is a possible "double-gutter* configuration in the fossa, with a hint of a conchal crest on the lateral nasal wall, quite low down. The anterior root of the zygomatic arch is broken oft; it was probably invaded by the maxillary sinus, and takes origin above the P2 and close to the infraorbital groove. The intraorbital region faced forward. A stout pillar rises from the C root to beyond the midpoint of the nasal aperture, forming a rounded surface adjacent to the sharpening lateral margin. T h e small and downwardly pointing infraorbital foramen lies in a sulcus lateral to the pillar, moderately close to the inferior orbital margin, and a groove descends from it to fade out well above the region of P I . The palate was uniformly deep in its preserved portion, but has sloping sides. The trontal lobes extended well over the rounded orbital cones, between which there is a deep sulcus housing the cribriform plate. T h e frontal crest continues down in

MAKAPANSQAT

the midline to bisect the cribriform plate. There is no true crista galli. The R lesser wing of the sphenoid is short m/1, and was posteriorly projecting, probably into a clinoid process. There is no red superior orbital fissure and no inferior fissure, cither, though the optic foramen is preserved. The sphenoid sinus was large in the hypophyseal region. Teeth. The teeth are quite well worn. The C root uras relatively small and short. P i was and P2 is chunky and large relative to M l , which is somewhat smaller than M2. P2 is longer m/d lingually than P I , but both arc rounded on that side. On P2 the peripherally placed paracone and the more internal protocone are opposite one another, and lie mesially. There is a marked distal style buccally, at the end of a thick distal crest that emerges distally on the protoconc before curving tighdy around; it appears that a similar crest emanated from the P I protoconc. The P2 anterior fovea is tiny; the posterior is much larger. M l is subsquare, and its metacone is noticeably m/d shorter than the larger paracone to which it is appressed. The protocone is larger and probably was more internally placed than the large, distally swollen hypocone. There appears to have been a very short, thick postprotocrista terminating at the base of the metacone, and a longer but somewhat thinner preprotocrista that courses mesially around the paracone to terminate near its buccal surface. A very short postcingulum courses from the d/b surface of the hypocone to terminate as a faint metastyle on the distal side of the metacone, well short of its buccal surface. The M 2 metacone is subsequal in size to the paracone; both cusps are peripherally placed. T h e hypocone is swollen d/1 and somewhat compressed m/d, the distal part of the tooth being further swollen by a short, thick, very peripherally placed postcingulum between the hypocone and the metacone. T h e postprotocrista is very faint and terminates at the base of the metacone; the m/d very thick preprotocrista terminates on the mesial side of the paracone, midway up the cusp. There are faint parastyles on both M l and M 2 . MLD 9. Part of a R lower face and maxilla, with P 1 - M 2 extremely worn, and alveoli for the anterior teeth. Goes with 12. The nasoalveolar clivus was not very long, and curves quite sharply downward. At the back it flows smoothly into the nasal cavity. T h e large incisive fossa hes well within the nasal cavity, and the incisive canal is unusually large. T h e posterior pole of the clivus

221

moderately overlaps the posteriorly thickening palate. The infcrolateral nasal corner is rounded (with a possible double gutter), and the inferior margin seems to have run slightly upward toward the midline. There is a distinct canine fossa lateral to the region of the C root. The preserved region of the pillar is flat anteriorly, and sharply cornered laterally above. The anterior root of the zygomatic arch faces forward and originates inferiorly quite close to the P 2 - M 1 . It also arises close to the canine fossa, and angles out quite strongly laterally. In side view it is anteriorly facing, flat and vertical. The maxillary sinus did not extend anteriorly beyond M l , but did penetrate the anterior root of the zygomatic arch laterally. The palate is shallow anteriorly and deepens somewhat posteriorly, with sloping walls. The apparently single incisive foramen lies level with the P I , and is continued anteriorly by a distinct groove. The I and C roots were apparently stout, the I roots short but the C root quite long. PI and P2 were wider b/1 than long m/d, and were large relative to the M l , which was smaller than the M 2 . MLD 11/30. Two maxillary fragments (one a cast of the specimen from which the isolated teeth were extracted) plus four isolated teeth in bone bits. The two maxillary parts articulate. The RI 2 has a broken root and the crown is partially worn; the crown is small, narrow, laterally rounded and faindy shovelshaped (reminiscent of the heteromorphic incisor type). The R upper C is apparently uneruptcd; it is small (female-sized), with a short sloping mesial edge and a longer, steeper, distal edge. Lingually there is a longer mesial margocrista and a shorter distal one that come together at a basal swelling. The buccal side is swollen. There is a partially erupted R P \ with compressed and subequal paracone and protocone lying opposite one another and slighdy mesially placed; the mesial and distal edges are divergent and subequal. Mesial and distal crests run from the protoconc, the distal one enclosing a larger fovea. The inner faces of the cusps are somewhat wrinkled. There is a partial RM 1 (30) in a shallow palatal fragment with uneruptcd teeth, disclosing a stepped-down nasal cavity. M l is partially worn, preserving a welldeveloped protostylar shelf around a large protocone that is quite thick mesially. An m/d compressed hypocone that extends lingually more than the protocone lies opposite the metacone; a short, thick postcingulum emerges from its distal side, quite near

\ *>*>*>

SotTT. ENTRIES

die Uncial scrfaoe, 2nd pnccuK'v cc?o3?d cc2y x* rxr buccals* 25 the s o ; of die roet^ocoe- It Epptirt wilt die prorocooe "was siKne-wiu: iatenuljy placed- There vrzs a thick, naesiilh* directed preprotccrista 2nd 2 less Click po^TpTozocriszz that terminated at the internal base of die roerzooae.i/LD J2. R maxillary fragment with extremely worn and broken M 3 . Urunformative, but goes with M L D 9. .'./LZ> 2J. Small L maxillary fragment with worn 12 and PI and C alveolus. A low pillar rises from the canine alveolar region, with a hint of canine fossa behind and a "hammocked" nasoalveolar clivus medially. The lateral incisor is flared laterally and is shallowly shoveled. The C root is neither large nor long. PI is chunk}-, with a centrally placed paracone and a somewhat mesially shifted protocone, and small anterior and posterior foveae. Buccally there is a faint mesial pillar that distends the tooth a bit, whereas the lingual side is evenly rounded. The P I compares favorably with that in 11. Part of 6. MLD 28. Part of a R maxilla, with broken and very worn M2 and worn M 3 , neither very large. Posteriorly the palate was not deep, but its wall was vertical. The posterior part of the anterior root of the zygomatic arch lay over the region of M 2 . On M 2 the metacone is somewhat truncated and large, but the hypocone that lies opposite it is not lingually distended. There was apparendy a thick but b/1 short postcingulum connecting the distal sides of these two cusps. On M 3 the metacone is quite small compared to the paracone and is m/d compressed. The large, mesially shifted protocone is more distally distended than the m/d compressed, b/1-oriented hypocone, which lies a bit distally under the metacone. A short postcingulum emerges from the distal side of the hypocone, somewhat near the lingual surface, and terminates as a small cuspule on the distal side of the metcone, midway along its base. There are traces of vertical grooves, especially lingually. MLD 4 J. Part of a crushed maxilla with a broken upper molar, somewhat worn. It shows a thickened cuspule-like postcingulum partway along the base of the metacone. MLD 44, Upper LM, probably M 1 . This is a somewhat worn tooth that is squarish with a rounded distal side. Buccal cusps are peripheral and somewhat

compressed; the Enc^jJ OHT& Are nxro « * * « * ^ the pcccc-ceoe is jxKTKxhi: insertulh- r\*cc\i, * « \ riiioi cinpLum compJerciy Around its fcj^ A.„% becomes eea&scm with an equally thick r.rc-v* teenstt that continues wp the mesial >.^c ^3 \\* paracone, A Kireiv distinguished p^tpr\>rvvruta terminates internally on the base of the mctAvvnc* whkH is sur>equal in sire with the ruraevme. The hvt\\\ M w ^ compressed m/d and h i oriented* and lic> VhchuY ^ the distal side oi die metacone. A very thick postcingulum emanates from the distal side of the hypocone, well away from the lingual side, and terminates part way up the base of the metacone AS A small cuspule. Buccally there were a slight parastvtc and pillar on the paracone. Enamel was somewhat wrinkled with some disputation. MLD 45. Part of R lower nasal region and anterior maxilla, with a somewhat worn P i , The infcmlater.it nasal margin curves smoothly in frontal view, and flows uninterruptedly from the nasal cavity onto a downwardly curving and probably long nasoalveolar clivus. A thick low pillar rises from above the region of the C root to run alongside the preserved part of the nasal aperture. The pillar is delineated postcrolaterally by a well-defined fossa (cf. 6), immediately behind which the anteriorly facing anterior root of the zygomatic arch emerges. The lateral crest curves in strongly. The palate is moderately deep under the region of the preserved PI, and probably deepened posteriorly. The damaged cross section ol the nasaoalveolar clivus, incisive canal and palate arc reminiscent of 9, including a posteriorly s/i thickening palate. There was possibly a faint double gutter. The large maxillary sinus does not extend forward

beyond P2. The P I resembles the PI of 23, which goes with 6. In the PI the protocone is somewhat shifted mesially, while the paracone is centrally placed with the mesial slope only slightly longer than the distal. There is a faint pillar buccally, going toward the mesial side of the paracone, where the thin prcprotocrista terminates; thus the buccal side of the tooth 1* less continuously rounded than the lingual side. 1 he groove between the protocone and paracone is shallower than in 23, and the cristac arc slightly different. Sts 5 Cranial Morph (includes M L D 37/38) MLD 37/38. Shearcd-off posterior part o( a neurocranium plus maxilla with broken and very worn

M AKAl'ANSOAT

M1-M3 and LM2. Surface is very weathered, the braincasc thin-boned. The remaining braincasc profile is flatfish at the top and quite rounded at the rear, though the relatively Mat and inwardly angled nuchal plane slightly undercuts the occipital plane. From behind, this is a relatively tall skull, coronally curved, that curves outward strongly at the mastoids. Widest point is across the mastoid regions. Lambdoid and sagittal sutures are shallowly denticulate and unsegmentcd. Part of the coronal suture is preserved from just to the left of and somewhat across bregma; it appears to be finely interdigitatcd and unsegmentcd. The alisphenoid is smoothly but sharply angled inferiorly, delineating a deep infratemporal fossa. The squamosal was long and probably not very tall, and the anterior squamosal area flows directly into the shallow greater wing of the alisphenoid with no angle. The thick supramastoid crest thins rapidly to the suprameatal region, and there is no clear supramcatal crest, though there is a sharp margin to the superior border of the meatus, maybe accentuated by breakage. The crest is confluent with the posterior root of the zygomatic arch, which flares quite strongly laterally to form a m/1 broad and a/p quite long shelf. As seen on the R, the posterior root of the zygomatic arch flared quite strongly laterally. The lateral part of the articular fossa lies under the shelf of the posterior root. As seen on the R, the lateral aspect of this shelf is vertical. The articular fossae are wide m/1 and fairly deep, with a long posterior slope and a shorter anterior slope that flows anteriorly over the shallow eminence. On the R there is a thick, short, laterally placed postglcnoid plate, and on both sides a low medial articular tubercle partly closes off the fossa. The fossae are angled slightly forward and extend laterally below the projecting posterior root of the zygomatic arch. On both sides the meatus is relatively large and subround, and the moderately thick-walled cctotympanic tube bears evidence of a centrally placed and moderately low vaginal process that is well separated from the mastoid and may have extended to the edge of the meatus. The posterior surface of the mastoid process, as seen on the L, is broad and flat. It faces somewhat laterally as well as back and down. The blunt tip of the mastoid projects slightly and is bordered medially by a broad, moderately deep but not very long mastoid notch with a distinct rim posteriorly and no digastric fossa. The posteromedial border of the notch bears a substantial paramastoid crest that ends just lateral to

the occipitomastoid suture. On the L is visible a low but broad Waldeyer's crest that runs a/p and is quite posteriorly placed. On both sides there is a large stylomastoid foramen. On the L this lies at the front of the mastoid notch. The bases of the moderately large styloid processes are visible on both sides, quite medial and somewhat anterior to the stylomastoid foramina. The bodies of the petrosals angle sharply up from the tubes, and bear large pseudostyloid processes. As seen best on the R, the relatively small carotid and jugular foramina arc close to each other and open into a common vestibule. The carotid foramen points down and back, and the jugular foramen forward. The carotid foramen lies quite medial to the styloid process. The occipital plane is short s/i and not very wide laterally. The region of the superior nuchal line is level with asterion and the steep course of the lambdoid suture is irregular on its way from asterion to lambda. The superior nuchal line was apparently not very distended, but in the midline there is a stout, long and somewhat projecting external occipital protuberance. The foramen magnum was moderate in size and subcircular. As detectable on the L, the condyle was fairly anteriorly placed. The basiocciput tapers strongly anteriorly, is bilaterally scalloped above the condyle and sharply flexed up. The relatively large foramen ovale lies lateral to the lateral pterygoid plate, and the foramen spinosum lies entirely within the sphenoid. There is no visible parietal notch. The squamous surfaces arc vertical, and only in the region of asterion docs the parietal turn out slightly. The pterygoid plates arc parallel to one another, and confluent at their bases. The palate is deep posteriorly, with vertical sides. Teeth arc too damaged for us to be able to say much about them, except that the preserved part of the short M3 is highly cuspidated. M L D 2 Lower Dental Morph MLD 2. Mandible of juvenile lacking rami. Pis and M2s arc erupting, P2s are in their crypts (L is visible); the very worn R dm2 and M i s arc in place. RC tip is just visible in its crypt. Alveoli for des and Is arc present; the tip of the permanent canine is just visible. The corpora are quite broad m/1 and deeper at the front than posteriorly. There is a tight inside curve at the front, but externally the symphysis is somewhat flat across. In profile the symphysis is fairly straight, with a slight backward tilt. The postincisal plane is ^ - ^

OOA

SITE

quite long and steeply inclined, curving down and in toward the inferior margin. There is a very tiny genial pit, but no torus below. On the R there is a hint of a mylohyoid line, and on both sides there are shallow submandibular fossae below the molars. Tiny traces of digastric fossae face down. The rami rise at the level of M l and thicken the corpus substantially, obscuring part of M2. There was perhaps a narrow mandibular gutter. On both sides three tiny mental foramina lie below the region of M l . The Is were quite wide-rooted, but not long. P i s and P2s are chunk}' and relatively large (especially b/1) compared to the M l , which is small (especially m/d) compared to the M2. On both sides, the subtriangular PI is a bit shorter m/d than the more roundedly square P2. The buccal side of PI is broadly arced, while the lingual side is more tightly curved, with the side mesial to the lingual "apex" of the triangle straighter than the more rounded distal side. The b/1 compressed and peripherally placed protoconid is very long m/d, and the more internally placed and bluntly peaked metaconid appears to rise up from the internal side of its base. The apex of the somewhat exodaenodont protoconid is slightly mesially situated and that of the metaconid is even more so. The metaconid is incorporated into a thick cresting system that curves mesially and then d/1 from the protoconid, swings sharply around the former cusp, and then turns broadly d/b to terminate as a stylid-like thickening on the distal side of the protoconid. This cresting system encloses a small but deep, somewhat buccally placed and slightly lingually facing anterior fovea, and a larger, upwardly facing, but much shallower distal fovea. Buccally the mesial and distal edges of the tooth are divergent and subequal and there is a faint mesial pillar, at least on the R side. On the LP2 the low, subequal, mesially shifted and slightly internally placed protoconid and metaconid lie opposite one another. Buccally there is a mesial stylid at the end of a short cristid that arcs from the side of the protoconid and then d/1 somewhat around the metaconid, enclosing a b/1 wide, shallow and not very m/d long anterior fovea. Distally a larger stylid represents the terminus of a thicker and somewhat wrinkled cristid that courses low down to the side of the base of the metaconid, enclosing a b/1 wide, moderately m/d long posterior fovea that is bounded mesially by an almost vertical wall formed by the coalescing bases of the protoconid and metaconid. The surface is thickly crcnulated.

ENTRIES

The worn Rdm2 is rectangular, and there an to have been a shallow notch between the hvpocov! and the probably centrally placed hypoconulid "nL metaconid was probably the largest cusp. R a n c j i w . and M2s are similar in being roundedly rcctaneul and in having a thick cingulid around the base of th protoconid, and lingual cusps that arc more peripheral and slightly taller than the buccal cusps. On Ml an d M2, there is a small but distinctive pit on cither sid of the very large and wedge-shaped hypoconulid which on M l is centrally placed and on M2 a bit buccally shifted. O n both Ms the wedgc-shaped hypoconid crosses the midline of the tooth to contact both the m/d long metaconid and the smaller, wedecshaped entoconid; a very modest triangular paracristid is inserted between the bases of the protoconid and metaconid. T h e enamel of M2 is somewhat pitted occlusally. The M i s and M2s have good-sized hypoconulids. On M l these arc centrally placed; on M 2 they are buccally shifted. M2 is a bit wider b/l and noticeably longer m/d than M l . Taung Lower Dental ("twin basin") Morph (includes M L D 5) MLD 5. Relatively m/d long and b/1 narrow Rdm2i unworn, with a mildly cuspulatcd occlusal surface. There is a wcll-devclopcd and beaded paracristid that fronts a deep and b/1 wide fovea. Behind, this fovea is bounded by cristids that run down the internal faces of the metaconid and protoconid. These crests front a second b/1 wide and deep basin that is bounded distally by another set of crests that runs between the apices of the mesial cusps. There is a distinct buccal cingulid between the bases of the protoconid and hypoconid, a fairly large mctastylid and a short, d/1facing cristid and pit between the entoconid and the moderate, somewhat buccally placed hypoconulid. T h e hypoconid extends across the midline into the long talon id basin, and there is a notch between the hypoconid and hypoconulid. There is some deep crenulation in the basin. T M 1517b Lower Dental Morph (includes M L D 4, 18,19,24) MLD 4. Relatively small but b/1 wide and somewhat m/d long LMj in a bone fragment. It is worn occlusaily and straight across the rnciial interstitial surface, and it tapers a bit to the rounded distal end. The large protoconid and almost a* large

M:A K A P A N S C A T hypoconid extend across the midline of the tooth, the f'rmcr cusps making full contact with the somewhat h/I compressed mctaconid. The blunt, squarcd-up b-isc of the latter contacts the mesial portion of the i/d quite elongate but b/I somewhat compressed cntoconid. The squarcd-up base of the fairly buccally placed and moderately sized hypoconulid contacts the distal portion of the cntoconid. A rather m/d thick, d/1-facing cristid with a pit on its inner side courses between the distal sides of the hypoconulid and cntoconid. There is a notch between the hypoconid and hypoconulid. Grooves suggest there was a cuspulid between the cntoconid and mctaconid. MLD IS. R mandibular corpus with all teeth, worn, extending across midline to include L I 1 - C . Partial roots of LP1 and part of P2. Corpus lacks inferior margin anteriorly, but was relatively deep and broad. Symphysis is mostly missing externally, but was relatively curved across and quite straight and slightly retreating in profile. Bilaterally there are depressions below the roots of the I2s. Internally there is only a modestly sloping postincisal plane with a rounded drop into the moderate genial pit. There is no trace of a mylohyoid line, but a shallow submandibular depression lies under M 1 - M 2 . The large single mental foramen lies under P2. Where the anterior root of the ramus rises beside M 2 , the bone is thickened considerably, and there is a smallish gutter between the ramus and the M 3 , which it mostly obscures. The jaw curves quite tightly across the front, especially on the inside, and the tooth rows are somewhat divergent. The roots of the highly worn anterior teeth arc stout but not very long; they were probably originally quite tall-crowned. Lingually the very worn RC preserves a distal margocristid, and shallow mesial and distal foveac. The Ps arc chunky; P I was m/d longer buccally than lingually, and truncated d/1. T h e slightly m/d and b/I larger P2 was m/d longer lingually than buccally. Both Ps have very mcsially situated protoconid and mctaconid regions, with some buccal distension of the former. P2 is much shorter m/d and somewhat narrower b/1 than M l . M 2 is wider b/I and was longer m/d than M l . M 3 is narrower b/1 than M2, and is a long tooth that tapers slightly toward its distally rounded end. Although worn, M 3 is much less worn than the other teeth. It has a d/1-facing crest and pit between the m/d elongate cntoconid and the moderate, mostly buccally placed hypoconulid. T h e

225

blunt base of the hypoconid extends across the midline to contact the mesial part of the entoconid, while the blunt base of the hypoconulid contacts the distal part of the cntoconid. The talonid basin was quite long, and the tooth quite wrinkled. There is an indication of a small cuspulid between the large metaconid and the smaller cntoconid. MLD 19. L mandible fragment with worn M 3 . Corpus is thick b/1, but not very tall s/i. Part of the ramus is preserved, and would have obscured M 3 . There is some mandibular guttering. M 3 is quite worn, tapering distally with shallow vertical grooves around its sides. It was somewhat cuspulatcd, and has a small d/1-oricntcd cuspulid between the buccally shifted, somewhat m/d compressed hypoconulid and the cntoconid, which it contacts. There arc pits between the three buccal cusps, and a cuspulid (metastylid) between the mctaconid and the entoconid. The blunt base of the hypoconid extends across the midline of the crown, contacting both the m/d long, b/1 somewhat compressed mctaconid and the even more b/1 compressed entoconid. MLD 24. Heavily worn crown of lower L probable M i . There is a suggestion of a buccally shitted, m/d compressed hypoconulid and a distal cristid between it and the m/d compressed cntoconid. St\V252-Like Isolated Teeth MLD 42. L lower C, very worn. Stout long root, narrow-crowned, bearing a distal stylid with a buccal pillar and lingual margocristid; the distal margin was apparently longer and steeper than the mesial margin (cf. the isolated St\V lower C). MLD 43. LI 1 . Small mamelons still visible; tip of large root is broken. Crown is tall, broadly flaring and is concave lingually with vertical grooves, St\V 252-

like. Unassignable to Morph MLD L Posterior parietal/occipital fragment. Fairly thin-boned cranial roof, thickening posteriorly. In profile it is quite rounded, but there is a marked obtuse angle between the occipital plane and the downwardly inclined nuchal plane. In rear profile the cranial vault was probably relatively low and modestly wide, and widest across the mastoids. What look like temporal lines arc very close to the sagittal suture

226

SITE ENTRIES

anteriorly, where the skull is broken, and seem to curve backward and down to the mastoid region. On the R the parietal curves sharply out to the mastoid region, and there may have been a rather oblique parietal notch. The occipital plane was low and not very wide, and the angle with the nuchal plane was level with asterion. There is only a very faint and low external occipital protuberance. The broken foramen magnum was probably long and ovoid. The superior sagittal sinus is faint, as arc the transverse sinuses, the left diverging above and the right level with the thick internal occipital protuberance. The depression for the R occipital lobe is slightly larger than that for the L, as was probably the case for the cerebellar lobes, MLD 3. Partial natural endocast (3d) and associated partial L parietal (J) with sagittal and coronal sutures. Parietal is thin boned, and both sagittal and coronal sutures are finely denticulated and unsegmented. There is some parietal bossing of the small, low, wide braincasc. Temporal lines are not really visible. The parietal notch was apparently shallow, and probably the parietal inserted fairly obliquely. The squamosal was low and probably long, and the lambdoid suture slopes up gently from asterion. MLD 10. Fragment of posterior cranial vault with lambda. Bone is moderately thick. Broad temporal lines run back close to sagittal suture, then curve out and down before lambda. The preserved portion of the lambdoid suture is finely interdigitated, undifferentiated and more or less arcs across lambda. There is some irregularity of the bone surface below lambda. The skull itself may have been moderately high and rounded. Internally, the sagittal sinus is visible anterior to lambda. MLD 22. Cast of a now-missing broken L mandibular corpus, with large, very worn M 2 - M 3 . MLD 27. Damaged front of a mandible with alveoli of L - R C and part of root of PI. Internally there is a tight angular curve, suggesting that the corpora diverged posteriorly. The postincisal plane is short and steep, with a large pit below. This was probably not a very tall jaw. On the R there is a small depression below the roots of II-12. C alveoli suggest large roots; I alveoli arc bulky and short. MLD 29. Broken L anterior mandibular corpus, with very worn and broken P2 and M l . The corpus is

moderately tall s/i and wide b/1, with a very t' K internal curve at the symphysis. Mental foramerf '* large, and lies below P2/M1. There is a thickened inferior transverse torus, with a pit above. P2 chunky and appears to have been moderately \ZTZt g relative to M l . MLD 34. Posterior part of a R mandibular corpus with roots of M1-M2. Moderately tall but quite thick m/1, with the bone swelling laterally in the region of M2 where the anterior root of the ramus arises. There is a shallow submandibular depression but no mylohyoid line in this region, and from the preserved inferior margin it appears that the anterior curve was sharp and the jaw itself short. M2 was slightly larger than M l . MLD 31. A petrosal fragment with a very small mastoid process, suggesting it is subadult.The mastoid notch is fairly broad, long and well defined, and medial to it the bone descends to the occipitomastoid suture. High up on the mastoid there is a small sulcus beneath the supramastoid crest. The vaginal process was thick, peaked around the styloid pit and probably extended to the margin of the meatus. Internally, the superior surface of the petrosal is flat; there is no evidence of a subarcuate fossa but the sub-subarcuate fossa is long and deep. The sigmoid sinus is long, deep and apparently contained within the temporal. There is no trace of a superior petrous sinus. MLD 40. L hemimandible with broken C and P 1 - M 2 , highly worn, roots of M3, and alveolus of 12. The corpus is thick m/1 and fairly deep s/i. It appears that the postincisal plane was moderately long and somewhat sloping, curving down smoothly at the level of P2 and then inward toward the inferior margin. Inside and out, the front of the jaw was apparently tightly curved with minimally divergent tooth rows. There is no evidence of a mylohyoid line, but there is a long and very shallow submandibular fossa below the molar region. The base of a very stout and prominent crest that had coursed up the middle of the ramus flows into the upwardly curving internal alveolar crest. The large and compressed mandibular foramen lies behind the stout crest, facing up and back, and a mylohyoid groove ran down from it. The relatively large mental foramen lies below P2-M1The anterior root of the ramus swells markedly laterally as it rises from the level of M2 and curves strongly upward; it would have obscured part of the

MAKA PAN SCAT

M3 and is separated from it by a modest gutter. The corpus is thickest level with the mesial part of M3 and then thins into the ramus, although the gonial region itself was probably not very thin. The 12 alveolus may have been enlarged during preparation; as it looks now, it would have housed a thick root. The broken C, which is somewhat obliquely set in the jaw, is not very stout-rooted. The relatively slender but probably somewhat tall crown preserves a low distal margocristid lingually, with a small fovea mesial to it. PI is slightly smaller than P2 both b/1 and m/d, and differs in outline, being slightly truncated m/1 with more m/b distension; it is thus longer m/d buccally than it is lingually (i.e., it is subwedge-shaped). P2 is narrower m/d buccally than it is lingually (and thus is roundedly triangular), and appears to have been large relative to the M l , which is shorter m/d and somewhat narrower b/1 than M 2 . The preserved outline of the slightly distally tapering M3 is longer m/d than that of the M2, although the two are subequal b/1. Ml—M2 have subequal and somewhat mcsially shifted protoconids and mctaconids, very long and d/1 curving hypoconid regions, entoconids that are larger than the metaconids, and buccal notches between the protoconids and hypoconids. A pit is preserved between the bases of the protoconid and hvpoconid on M 2 . The small, distallv pointed hypoconulid is centrally placed on M 2 and there is a notch between it and the entoconid. It appears that a small hypoconulid lay close to the entoconid (thus lingually) on M l .

REFERENCES Biackwcll, B. A. B. ct al. 2001. ESR dating the hominidbcaring breccias at Makapansgat Limeworks Cave, South Africa./ Hum. Evol. 40: A3-A4. Dan, R. A. 1925. A note on Makapansgat: a site of early human occupation. S.AJr.J. Sci. 22: 454. Dart, R. A. 1948a. The Makapansgat proto -human Australopithecus prometheus. Am. J. Phys. Anthropol. 6: 259-284. Dart, R. A. 1948b. The adolescent mandible of Australopithecus prometheus. Am. J. Phys. Anthropol. 6: 391 -412. Dart, R. A. 1949a. The cranio-facial fragment of Australopithecus prometheus. Am.]. Phys. Anthropol. 7: 187-214. Dan, R. A. 1949b. Innominate fragments of Australopithecus prometheus. Am. J. Phys. Anthropol. 7: 301-333.

227

Dart, R. A. 1949c. A second adult palate of Australopithecus prometheus. Am. J. Phys. Anthropol. 7: 335-338. Dart, R. A. 1954. The adult female lower jaw from Makapansgat. Nature 173:286-287. Dart, R. A. 1955. The first australopithccine fragment from the Makapansgat Pebble Culture stratum. Nature 176: 170-171. Dart, R. R. 1957a. The ostcodontokcratic culture of Australopithecus prometheus. Mem. Transvaal Mus. 10:1-105. Dart, R. A. 1959a. A tolerably complete australopithccine cranium from the Makapansgat Pink Breccia. S.AJr.J. Set. 55:325-327. Dart, R. A. 1959b. The first australopithccine cranium from the pink breccia at Makapansgat. Am. J. Phys. Anthropol. 17:77-82. Dart, R. A. 1962a. The Makapansgat pink breccia australopithecinc skull. Am. J. Phys. Anthropol. 20:119-126. Dart, R. A. 1962b. A left adult mandible and nine other lower jaw fragments from Makapansgat. Am. J. Phys. Anthropol. 20: 267-286. Day, M. H. 1965. Guide to Fossil Man, 1st cd.. London: Casscll. Henries, A. and A. Latham. 2002. Dating the depositional sequence and australopithccine "Grey Breccia" of Makapansgat Limeworks using magnetostratigraphy. Am. J. Phys. Anthropol. Suppl. 34: 84 - 85. Holloway, R. L. 2000. Brain. In: E. Dclson ct al. (cds.). Encyclopedia ofHuman Evolution and Prehistory, 2nd cd. New York: Garland Press, pp. 141-149. Maguire, J. M. 1985. Recent geological, stratigraphic and palaeontological studies at Makapansgat Limeworks. In: P. V. Tobias (cd.), Hominid Evolution: Past, Present and Future. New York: Alan R. Liss, pp. 151-164. McKee, J. K.,J. F. Thackeray and L. R. Berger. 1995. Faunal assemblage sc nation of southern African Pliocene and Pleistocene fossil deposits. Am. J. Phys. Anthropol. 96:235-250. Partridge, T. C. 1979. Reappraisal of lithostratigraphy of Makapansgat Limeworks Site. Nature 279: 484-488. Reed, K. E. ct al. 1993. Proximal femur of Australopithecus ajricanus from Member 4, Makapansgat, South Africa. Am.]. Phys. Anthropol. 92:1-15. Vrba, E. S. 1985. Early hominids in southern Africa: updated observations on chronological and ecological background. In: P. V. Tobias (cd.), Hominid Evolution: Past, Present and Future. New York: Alan R. Liss, pp. 195-200. Repository Department of Anatomy and Human Biology, University of the Witwatcrsrand Medical School, York Road, Parktown, Johannesburg 2193, South Africa.

SITE ENTRIES

228

mm ^^H

1 j

Uw

EaS--^

m£, £jm

mmim B S E S SB

Kfifc" ^f^T^pS

MAKAPANSGAT

Figure 1. MLD 1, parietal/occipitalfragment(scale == 1 cm).

MAKAPANSGAT

MAKAPANSGAT

Figure 2

229

. MLD 2, partial juvenile mandible (scales - 1 cm).

A

230

JS.IT K E-NTU I Bfci

MAKAPANSGAT

Figure3. L:MLD5,lowerRdm2:R:MLD4,lowerLM3(scale = 1 cm).

MAKAPANSGAT

MAKAPANSGAT

Figure 4. MLD 6, partial lower face (scales = 1 cm).

231

SlTR

2X2

MAKAPANSGAT

EHTRIBS

Figure 5. MLD 9, partial R maxilla (scales = 1 cm).

MAKAPANSGAT

MAKAPANSGAT

Figure 6. MLD 10, fragment of posterior cranium (scale = 1 cm).

233

234

SITE ENTRIES

Figure 7. Left image: L, MLD 11, upper canine; R, MLD 30, upper PI in part of maxilla. Right image: MLD 30, internal view (scale = 1 cm).

MAKAPANSGAT

235

MAKAPANSQAT

MAKAMNSOAT

Figure 8. MLD 18, partial mandible (icaies

I em)

SITE ENTRIES

236

MAKAPANSGAT

Figure 9. Lower molars. L: MLD 19; R: MLD 24 (scale = 1 cm).

MAKAPANSGAT

Figure 10. MLD 27, fragment of L maxilla (scale = 1 cm).

MAKAPANSGAT

MAKAPANSGAT

MAKAPANSGAT

Figure 11. MLD 31, R petrosal (scale = 1 cm).

Figure 12. MLD 37/38, partial cranium (scales = 1 cm; close-up not to scale).

237

238

SITE

MAKAPANSGAT

ENTRIES

Figure 12. (Continued),

MAKAPANSGAT

MAKAPANSGAT

Figure 13. MLD 40, partial L mandibular corpus (scales = 1 cm).

239

240

MAKAPANSGAT

lcm).

SITE

ENTRIES

Figure 14. From L to R: M L D 42, lower LC; M L D 43, upper I I I ; M L D 44, upper LM (scales =

MAKAPANSGAT

MAKAPANSGAT

Figure 15. MLD 45, partial R maxilla (scale = 1 cm).

241

242

SITE

MAKAPANSGAT

MAKAPANSGAT

ENTRIES

Figure 15.

{Continued).

Figure 16. MLD 45 (L) and MLD 23 (scale = 1 cm).

LOCATION Malema, western shore at northern end of Lake Malawi, about 50 km N of Uraha, Malawi (Map 3). DISCOVERY Hominid Corridor Research Project, 1996. MATERIAL RC 911, left maxillary fragment with M l and roots of M2. DATING AND STRATIGRAPHIC CONTEXT Recovered from Unit 3A of the Chiwondo Beds (Betzler and Ring, 1995; Bromage et al., 1995), a time-aggregated unit that spans the period between about 3.76 and 2.0 Ma. The associated fauna is mixed; but all elements are compatible with a provisional age of ca. 2.4 Ma for RC 911 (Bromage et al., 1995; Schrenketal., 1997). ARCHAEOLOGICAL CONTEXT Early reports to the contrary, no in situ artifacts are known from the Chiwondo Beds (Juwayeyi and Betzler, 1995). PREVIOUS DESCRIPTIONS AND ANALYSES Illustrated and briefly described by Schrenk et al. (1997), who attributed this fragmentary specimen to Parantbropus boisei.

MORPHOLOGY

RC 91L Very weathered L maxillary fragmer with very damaged M 1 - M 2 . Detailed morphology not discernible. This specimen is massive, very thic No sign of anterior root of zygomatic arch. M l - N are huge, and apparendy were extremely wide 1 compared to their length m/d. Huge buccal roots a exposed; they are not very splayed and we apparendy not very long.

REFERENCES Betzler, C. and U. Ring, 1995. Sedimentology of t Malawi Rift: fades and stratigraphy of the Chiwon beds, northern Malawi./. Hum, Evol, 28:23-36.

Bromage, T. et al. 1995. Paleoanthropology of the Mala Rift: an early hominid mandible from the Chiwon Beds, northern Malawi./. Hum, Evol. 28:71-108.

Juwayeyi, Y. and C. Betzler. 1995. Archaeology of t Malawi Rift: the search continues for Early Stone A occurrences in the Chiwondo Beds, northern Malawi. Hum, Evol, 28:71-108. Schrenk, F. et al. 1997. Geologic, Palaontologie u Palaoanthropologie des Malawi-Rifts. Cour, Forscb. Senckenberg201:409-419.

Repository Department of Antiquities, Lilongwe, Malawi.

SITE

244

MALEMA

ENTRIES

Figure 1. RC 911, L maxillary fragment (scales = 1 cm).

OLDUVAI G O R G E

LOCATION Thirty-km-long dry canyon in the Serengeti Plains of northern Tanzania, centered at some 160 km NW of Arusha, and adjacent to Ngorongoro Crater (Map 3). DISCOVERY Expedition of H. Reck, 1913 (OH 1); L. Leakey and co-workers, 1935 (OH 2); L. and M. Leakey and coworkers, 1955-1972 (OH 3-42; O H 5 discovered by M. Leakey 17 July 1959); M. Leakey and co-workers, 1973-1982 (OH 43-61); D. Johanson and others, 1986 (OH 62); R. Blumenschine and others, 1993present (OH 63-65). MATERIAL Remains (ranging from isolated or partial teeth and cranial or postcranial fragments to tolerably complete crania and skeletons) of over 60 hominid individuals 1~65) spanning almost 2 myr. Olduvai hominids include fossils attributed to both Paranthropus and Homo spp, although those attributed to the latter or regarded as indeterminate are far more common than the former. See Day (1986) for a complete listing (with specific localities) up to 1982 (OH 61).

history, and refinement of the Gorge's stratigraphy is still continuing. Intermittent local volcanic activity has, however, permitted K/Ar dating of a sequence of marker beds, unfortunately mostly confined to Bed I. The most recent synthesis of the geology of Olduvai is by Hay (1990), whence the details given below are taken, modified according to new Bed I dating by Walter et al. (1991) and the revised magnetostratigraphy ofTamrat et al. (1995). The lowest sediments exposed in the Gorge are those of Bed I, laid down in a shallow alkaline lake and its tributary streams; the hominid-yielding deposits of middle and upper Bed I are dated from around 1.9 to 1.75 Ma. The most important (and almost the only) Australopithecus/Paranthropus specimen of this short period is the O H 5 cranium (the holotype of Paranthropus boisei), found at the FLK. locality, close to the bottom of the sequence. Sedimentation of this kind continued through Bed II times, about 1.75-1.4 Ma, although faulting dramatically reduced the size of the lake at about 1.6 Ma. Bed II localities have yielded few elements attributed to Paranthropus, which was apparently already rare and had disappeared by Bed III times. ARCHAEOLOGICAL CONTEXT Stone tool assemblages are known throughout the Olduvai sequence, and indeed the Gorge has given its name to the very earliest recognizable stone tools known. The crude Bed I lithics are thus referred to the Oldowan tradition, characterized by small

UATING AND STRATIGRAPHIC CONTEXT ne walls of the Gorge expose a long sequence of latest Pliocene to latest Pleistocene lacustrine and fluviatile strata, dated to between 1.9 and 0.01 Ma. These -posits record complex local changes in depositional

245

« f t t u j « v -r* '>'•"-" '^

•-46

SITE

cores/choppers, battered hammcrstones and numerous simple flakes (M. Leakey, 1971b). Low in Bed II the Developed Oldowan appears, with fewer choppers and some crude bifaccs. In the upper half of Bed II, in contrast, beginning at about 1.6 or 1.5 Ala, large numbers of Achculean handaxes and cleavers begin to be found, although not at every occupation site (M. Leakey, 1971b). In Bed I and Bed II times hominid occupation at Olduvai seems to have been concentrated along the southeastern margin of the ancient lake, where several dense accumulations of cutmark-bearing mammal bones and lithics have been identified. O H 5, the first truly ancient hominid found in the Gorge, was initially hailed as the maker of the Oldowan tools found in relative abundance in its lowest levels (L. Leakey, 1959). However, the subsequent finding of the type materials of Homo habilis rapidly supplanted Paranthropm as the toolmaker, and the possibility that Paranthropm made the tools has not been seriously raised since. In fact, there is no positive evidence for the association of any particular Olduvai hominid with stone tools and butchering activity. PREVIOUS DESCRIPTIONS AND ANALYSES O H 5 was made the holotype of the new hominid genus and species Zinjanthropus boisei by L. Leakey (1959). Almost immediately Robinson (1960) noted the similarities between O H 5 and the South African hominids from Kromdraai and Swartkrans, and proposed that the Olduvai specimen be transferred to Paranthropm as P. boisei. Leakey, Tobias and Napier (1964) reduced both Paranthropm and Zinjanthropm to subgeneric status within Australopithecus y while Tobias (1967), in his magisterial descriptive monograph on the specimen, preferred (despite his book's title) an attribution to Australopithecus boisei. Nobody, however, has seriously questioned the specific distinction between this form and the South African "robusts," and currently the name Paranthropm (or Australopithecus) boisei is almost universally used to denote the eastern African "robust" forms of the 2 to 1.5 Ala period. Tobias (1967) and Holloway (2000) both give the endocranial volume of O H 5 as 530 ml. MORPHOLOGY T h e hominid assemblage from Olduvai attributed to Australopithecus boisei consists of the cranium O H 5, a couple of isolated teeth ( O H 26 and O H 60, not

ENTRIES

seen), and one postcranial fragment. The craniu * ls described below. OH 5. Cranium consisting of an extensively reconstructed face, plus the braincase; any contact between these two major areas is insignificant. The is substantial degradation of detail throughout. Th bone of the cranial vault is not notably thick. Although the face and neurocranium do not retain any points of contact, they can be aligned with reasonable certainty, and thus general cranial shapes and profiles will be offered in the description that follows. Face and Neurocranium. In profile the cranial vault is low and relatively short, but quite globular. The frontal recedes from the supraorbital region with no sulcus, and at a very low angle. The frontal profile would have curved quite flatly back, and then arced strongly downward toward the lambdoid suture from just behind porion. From the very low lambda, the profile of the occipital plane flattens out to run down to a very rugose superior nuchal line. Below this, the nuchal plane angles forward very sharply. Seen from above, the supraorbital margins are anteriorly oriented, with glabella swelling out broadly in front of them. There is extreme postorbital constriction, so that the temporal fossa extends medially to about the middle of the relatively shallow orbital cones. Viewed from the front the short-faced cranium is deep, and very broad across the zygomas and nasoalveolar clivus. And from the rear, the bulk)"; inferiorly swollen-looking mastoid regions extend (as better seen on the R) noticeably below the level of the almost horizontal nuchal plane between them and quite far laterally beyond the side walls of the neurocranium. As preserved on the R, the "exposed" superior surface of the mastoid region is gently concave and faces straight up. As seen on the L, the posterior root of the zygomatic arch protrudes even farther laterally than the mastoid process. Seen from behind, the side walls of the braincase curve up strongly from the medial region of this surface. At the region of the squamosal suture, this posterior profile arcs broadly and continuously in toward the midline, prior to which the R component of the sagittal crest turns acutely upward and is somewhat deflected laterally at its top. On the L, the curvature of the lateral cranial wall mirrors that of the K, but the L component of the sagittal crest begins its almost vertical rise closer to the midline, ultimately standing higher than the R side.

OLDIV.M

The orbits lie high up on the face, and are more less square with rounded corners, although their horizonul axes arc tilted slightly down toward the - 4^- The roofs ot the orbits are slightv elevated rela~-c to the anterior margins, but now smoothly out ^ up onto the "tori." The supraorbital tori exist as thickenings of the supraorbital margins, with no foru-ard or upward projection. Indeed, these are not tori in the stria sense, and the whole supraorbital region lies just behind the infraorbital region. The ridgelike temporal lines delineate the posterior margin of the supraorbital region. They parallel the anterior supraorbital margin medially, then turn sharply posteriorly, at the level of the very medially placed and broadlv shallow supraorbital notch, to converge toward the midline. At this point the lines define, between them, a shallow and subtriangular postglabellar depression. The temporal lines converged in an area of missing bone around bregma, to form a distinct and doubled sagittal crest that peaks in height by the level of porion, after which it diminishes in size to fade out well above the region of lambda. From this point, very faint temporal lines diverge again, and run down and laterally to bracket the area above the region of the external occipital protuberance and eventually to meet the expanded supramastoid regions. The interorbital region is quite broad, and does not narrow inferiorly. Lacrimal fossae are situated far forward, almost on the face. However, the lacrimal canal probably drained quite far back in the nasal cavity, as is suggested by the quite wide expanse of bone preserved on the R lateral nasal wall that shows no sign of a canal or a groove. The s/i very tall nasal bones, which rise well above the frontal processes, taper inferiorly. On either side of the nasals, inferiorly, the forwardly facing and not very tall frontal processes of the maxilla are slightly but distinctly concave. The nasal aperture is fairly tall, and is quite broad at its base. As preserved on the L, the superior part of the lateral margin of the nasal aperture is quite sharp; lower down, the lateral margins are quite blunt and rounded, and become smoothly confluent with the barely discernible inferior margin of the aperture, which runs smoothly out and down from the floor of the nasal cavity onto the long, broad and downwardly arcing clivus. The floor of the nasal cavity is poorly delineated from the clivus by low ridges that are defined by shallow depressions behind them. Anterior nasal spines are lacking, but a pair of low longitudinal crests rises between these two depressions, and would

GORGE

247

probably have supported the cartilaginous nasal septum. Also on the L, behind the crests, there is preserved what appears to be pan of the aperture of the incisive fossa. This lies quite far back relative to the palatal exit of the incisive foramen. It also appears that the floor of the nasal cavity would have descended significantly posteriorly. On the R, the relatively small infraorbital foramen lies well below the orbit, almost level with the floor of the nas,d cavity. Preserved on the L is a large bony canal descending from the region of the orbit; this probably housed the intraorbital nerve. Lateral to the orbits the zygomas arc forwardlv facing and arc concave s/i; inferior to the midline of the orbit the curvature changes to be more convex. This contour is continued down on to the vcrv s/i tall and forwardlv facing anterior zygomatic root. The anterior roots of the zygomatic arches originate well above the region of the P2s, and flare directly laterally for a short distance before terminating, as seen on the R, at a large and laterally oriented masseteric scar. The lateral part of the zygoma is oriented superolatcrally. The quite vertical squamosal portions of the temporals are very long a/p but, judging by the suture, were not sharply arced. Posteriorly, the squamosal curves to follow the rounded contour of the cranial vault. On both sides the parietal notch lies quite posteriorly, on the lambdoid suture. As preserved more fully on the R, the squamosal portion of the temporal bone is quite vertical (rather than medially inclined), which creates an m/1 wide parietal notch. The portion of the parietal that fits into this notch is thus rather wide m/1 and it also extends onto the occiput. On the R, a very large mastoid foramen lies above the bluntly expanded and shclflike supramastoid crest. This latter is confluent with the broadly shclflike posterior root of the zygomatic arch. The arch continues anteriorly as a stout zygomatic process that is modestly thick m/1 and somewhat tall s/i, and is broadly muscle-scarred on its inferior margin. This strut defines the lateral margin of a relatively wide temporal fossa, the anterior part of which is particularly expanded. On both sides, a jagged but incomplete crest delineates an infratemporal fossa from the temporal fossa. Again as judged from the better preserved R side, the supramastoid crest is delineated from the bulk)' mastoid process below by a horizontal groove, at least anteriorly. The mandibular fossa is wide m/1 and anterolatcrally oriented. Anteriorly it is bounded by a very welldeveloped and somewhat anteriorly inclined wall that

248

SITE ENTRIES

projects laterally away from the squamosal, and essentially consists of a downward flexing of the posterior zygomatic root anteriorly. Medially the fossa is closed off anteriorly by a very large, blunt medial articular tubercle that partially overlaps the body of the petrosal, and lies opposite the vaginal process from which it is well separated. The fossa is open between them. Posterolatcrally, as seen on the R, the fossa is bounded by a low, thick postglcnoid plate that is apprcssed to the nonpromincnt ectotympanic tube, and is essentially unbounded more medially. The external auditory meatuses are ovoid and oriented strongly anteriorly. The bone of the tubular ectotympanics is not very thick, and especially as seen on the L, the long axis of the tube is the same as that of the thin body of the petrosal. On both sides, a small-to-medium-sized styloid pit lies in line with and well behind the small, downwardly and slightly posteriorly pointing carotid foramen. The short, peaked vaginal process is essentially confined to the region of the pit, and thus lies on the posterior aspect of the tube rather than running down its midline. As seen on the R, the very small and slightly anteriorly oriented jugular foramen opens into the area of the carotid foramen. The foramen spinosum appears to have been contained in the temporal, and is far separated from the small, more medially placed foramen ovale that lies deeply seated in the sphenoid. In profile the mastoid region presents a very a/p long, almost pyramidal and quite strongly downwardly projecting mastoid process. Judging from breaks on both sides, the process is invaded by many tiny air cells. On the L a tall, vaginal process-like structure abuts the posteromedial aspect of the mastoid process, and on the R it appears that the base of the mastoid process medially was distended into a bulky and anteromedially oriented structure. There appears to have been no parietomastoid suture of any consequence, the posteroinferior portion of the parietal nestling right in at the region of asterion, overlapping the occipital. The very low-lying lambdoid suture rises gently from both asterions and probably curved round the region of lambda (there are small superficial ossicles missing in this region). The suture appears to have been uniformly irregular in denticulation throughout its length. The very s/i short occipital is very broad between asterions. The distended nuchal line forms a broadly M-shaped ridge, with a downwardly directed peak in the midline, in the region of the external

occipital protuberance. The edge of this feature is sharply delineated and the feature as a whole is emphasized further by strongly inwardly sloping nuchal plane. This plane is relatively flat, with twinned deep depressions on either side of the projecting region of the external occipital protuberance, whose tip is deeply indented for the ligamentum nuchae. The external occipital crest is a low structure near the small and heart-shaped foramen magnum. On the base, on the L, level with the posterior side of the mastoid process and separated from it by a well-defined, scooped-out depression (digastric fossa?), is a stout, thick, a/p-oriented crest (Waldeycr's?). On the R, a shallower and less clearly defined depression lies level with the posterior aspect of the mastoid process. The occipital condyles lie very anteriorly and slightly overhang the foramen magnum. Each has a distinct notch at its midpoint medially, probably representing the fusion of basioccipital and lateral parts. The condyles are not strongly arced in the coronal plane. A rugose line running across the basiocciput may indicate the position of the sphenooccipital synchondrosis, in which case the basiocciput would have been very short. On both sides small and patent condyloid foramina lie well above the condyles. The palate is long, very deep and relatively narrow, with fairly vertical side walls and a more sloping anterior boundary. The moderately large, single incisive foramen lies level with the septum between PI and P2, and a well-defined groove runs from the foramen to the region between the lis. Pterygoid plates are partially preserved on both sides; the lateral plates were large and probably quite flaring. Internally, the frontal lobes slightly overlapped the rear of the orbital cones and rose steeply between and above them; their impressions are separated by a distinct, long and very vertical frontal crest. The superior surface of the petrosal is broad m/1 and relatively flat, and on both sides there is a tiny peak corresponding to the superior semicircular canal. However, there is no proper arcuate eminence. 1 he subarcuate fossa on both sides is totally filled-in, but there is no sub-subarcuatc fossa. On both sides the carotid canal lies quite laterally in the petrosal. Definitely on the L, and probably on the R, its roof was not fully ossified. The sphenooccipital clivus is oriented strongly upward. The dorsum scllae is quite pronounced vertically but compressed a/p, with a broad, straight,

OLIHTVAI

riJgelike superior margin unadorned by projecting posterior clinoid processes. The hypophyseal fossa is essentially flat, and was probably wide from side to side as well as long a/p. The sphenooccipital region is thick s/i, and the region lying under, to its sides and anterior and slightly posterior to the hypophyseal fossa, is deeply invaded by numerous moderatc-tolarge air cells. Lateral to the sphenooccipital region, the bases of the alisphenoids were expanded by large air sinuses. The impression for the L occipital lobe is larger and more impressed than the R; the reverse is true for the cerebellar lobes, both of which arc larger than the cerebral lobes above them. There is no true internal occipital protuberance, but the internal occipital crest arises high up in the region between the occipital lobes. O n the R a crest, corresponding to the R transverse sinus, lies higher up than the more prominent crest on the L side. Lower down, on the internal occipital crest, the R and then (slightly more inferiorly) the L marginal accessory sinuses diverge, to course around the posterior margins of the foramen magnum. They exit, as seen on the R side, at the jugular foramina. O n both sides shallow sigmoid sinuses run behind and then below the petrosals, and, as seen on the R, they exit at the jugular foramen, possibly becoming confluent with the marginal acces-

sories. Teeth. T h e complete dentition is present, though some teeth are damaged, and all except for the M 3 s are heavily worn. T h e buccal roots of the RJV13 are exposed, showing root tips unclosed, and thus suggesting that eruption was incomplete. T h e anterior teeth are very small relative to the massive posterior teeth. It is hard to know how high-crowned the Is were originally, but the l i s are much larger than the I2s, and probably the disparity was much greater before wear. The lingual surfaces of all Is are weakly excavated and bear no swellings. T h e roots of the l i s are very large, and are much longer than those of the I2s. The C roots are less massive than those of the l i s , and the crowns are also narrower. In outline the Cs are somewhat pear-shaped, being m/d longer buccally than lingually. T h e anterior teeth are aligned almost straight across, with the Cs in the "corners" of the arcade. T h e P i s are slightly narrower b/1 and shorter m/d than the P2s, and apparently had three roots. T h e occlusal surfaces of P 1 - P 2 are massive. T h e protoconcs and paracones arc subequal in size, lie opposite one another and are centrally positioned. T h e buccal and

GoiUiF.

249

lingual surfaces of P i arc more swollen than those of 12. On the RP2 a thin posterior fovea is preserved. M l is narrower b/1 and shorter m/d than M2, and both arc squarish with rounded corners. M3 is about as wide b/1 as M2, but is slightly shorter and more ovoid, and more obliquely oriented. On M i s and the LM2 the paraconc is more distended buccally than the smaller mctacone; on RM2, the paraconc is not distended and the mctacone is relatively even larger. On M 3 , the buccal surface courses almost directly to the d/1 region of the tooth, thereby emphasizing'the paraconc region. M 1 - M 2 had large hypoconcs and very small protoconcs; the hypoconc region is also expanded on M 3 , whose cusps cannot be distinguished because of heavy enamel wrinkling (which continues on to lingual surfaces of these teeth). As seen on the R M 1 , a groove delineating the hypoconc courses steeply b/d to the b/1 midline of the crown, where it turns distally a very short distance before meeting what appears to have been a small basin or fovea just mesial to a very thick postcingulum. This may have also been the case on the M2s. Wrinkling on the M2s is also suggested by the presence of grooves, especially on the lingual sides of these teeth. The lingual and buccal sides of the M3s are swollen, and the regions of the apices of the cusps are somewhat internally placed. Heavy wear makes other observations difficult to make.

REFERENCES Day, M. 1986. Guide to Fossil Man, 4th ed. Chicago: University of Chicago Press. Hay, R. 1990. Olduvai Gorge; a case history' in the interpretation of hominid palcocnvironments in East Africa. Geo/. Soc. Am. Spec. Pap. 242:23-37. Holloway, R. 2000. Brain. In: E. Dclson et al. (eds): Encyclopedia of Human Evolution and Prehistory. New York: Garland Publishing; pp. 141-149. Leakey, L. S. B. 1959. A new fossil skull from Olduvai. Nature 201: 967-970. Leakey, L. S. B., P. Tobias and J. Napier. 1964. A new specie's of the genus Homo from Olduvai Gorge. Nature 202:7-9. Leakey, M. D. 1971. Olduvai Gorge, Vol. 3. Cambridge, UK: Cambridge University Press. Robinson, J. T. 1960. The affinities of the new Olduvai australopithccine. Nature 186: 456-458.

250

SITE

ENTRIES

Tamrat, E. ct al. 1995. Revised magnetostratigraphy of the Plio-PIcistocene sedimentary sequence of the Olduvai Formation (Tanzania). Palaeogeog.y Palaeoelimatol., Palaeoecoi. 114:273-283. Tobias, P. V. 1967. Olduvai Gorge, Vol. II: The Cranium of Australopithecus (Zinjanthropus) boisei. Cambridge, UK: Cambridge University Press.

Walter, R. et al. 1991. Laser-fusion ^Ar/ 39 Ar dating Bed I, Olduvai Gorge,Tanzania. Nature 354:145-149

Repository National Museum of Tanzania, PO Box 511 Dar Salaam, Tanzania.

OXDITVAI G O R G E

OLDUVAI

251

Figure 1. OH 5 cranium, anterior and posterior components (scales = 1 cm; close-up not to scale).

$»*«: EflTfclfcS

OLDUVAI

Figure 1. (Continued)*

OLDUVAI

OLDUVAI

Figure 1.

GORGE

{Continued).

253

O M O VALLEY, LOWER

(Shungura, Usno)

DATING AND STRATIGRAPHIC CONTEXT The lavishly fossiliferous Plio-Pleistocene sediments of the Lake Turkana Basin (in both its Kenyan and Ethiopian portions) are assigned to the Omo Group (see Brown, 1969; Feibel, Brown and McDougall, 1989). In the Ethiopian part of the Basin, three principal formations are exposed in the lower valley of the DISCOVERY Omo River, the main feeder of Lake Turkana. These Hominid fossils were first found in both Shungura are the Mursi, Shungura and Usno Formations (see and Usno sediments in 1967 by various contingents of Brown, 1969; de Heinzelin, 1983; Brown et al.,1985). the Omo Research Expedition under the direction of The underlying Mursi Fm consists of fluviolacustrine C. Arambourg, F. C. Howell and Y. Coppens. Colsediments, capped by a basalt flow that has been K/Ar lecting continued through 1972. dated to 4.0 Ma. It has yielded no hominid fossils. The Usno Fm is comprised of about 170 m of predominantly fluvial sediments that are correlative with the two lowest Members (A and B) of the Shungura MATERIAL Fm. The Usno hominids come from above a tutt A heterogeneous collection of more than 200 mostly dated to 3.3 Ma by correlation. The majority of the highly fragmentary hominid fossils comes from the Omo hominids come from the Shungura Fm, a much Shunsura Formation. The bulk of them are isolated thicker sequence (ca. 760 m) of lacustrine and fluvial teeth or small craniomandibular fragments, but sediments that were deposited between about 3.6 and among the better specimens are the hemimandible 0.9 Ma. Twelve members have been recognized, diL74-A-21; the massive mandibular corpus L7-A-124; vided up by K/Ar dated tuffs that have been identified the partial juvenile cranium L33S-V-6; the fragmenfrom A—H. Numerous supplementary ashfalls contain tary and rather gracile crania L894-1 and Omo 323; pumice clasts that have also been dated. Indeed, the and the mandibular corpus Omo 18-1967-18, holotype of Parazistrakpithecus aethiopicus. From the Usno major importance of the Omo deposits lies in the faunal calibration that this superb sequence of datable Formation come only a couple of dozen isolated teeth. fossiliferous levels has allowed. *Geochemical fingerSee Howell and Coppens (1974) for a full listing of printing'* of the Omo tuffs has also permitted hominid fossils from the 1967-72 field seasons, and correlation with ashfalls deposited over a wide area, Feibel Brown and McDougall (1989) for stratiincluding marine sediments in the Gulf of Aden and graphic provenances. LOCATION Collecting area of some 200 sq. km on W bank of Omo River, southern Ethiopia, just north of Lake Turkana (Map 1).

254

O M O VALLEY,

LOWER (SIIUNGUIIA,

ft* the Kenya coast that permit their correlation with L marine palcoclimatic record. The principal hominid-yielding levels of the Shun^ura Fm run from Member B to lower Member Q bracketing the period from about 3.3 Ma to 2 0 Ma, with most of the specimens from the 2.6-2.0 Ma interval. The Omo 18-1967-18 mandible is from about 2.6 Ma. The mandible F 044-1970-2466 dates about 2.4 Ma and the marginally younger partial Juvenile cranium L338-y-6 to 2.39 Ma. The mandible Q57-4-196S-41 is estimated at about 2.37 Ma, and the mandible L860-2 dates to around 2.33 Ma. From sljjrjitlv higher in the Shungura section (submembers Q3-G5), the partial mandibles L427-7, L74-A-21 and L7-A-125 date from 2.25 to 2.15 Ma, as probablv does the cranium 0.323-1976-896, located only to Member G. The mandible 0.222-1973-2744 from Submcmber G7 has an estimated age of 2.10 Ma, and the craniomandibular fragments 0.75-1969-14A/B come in at 2.02 Ma. All the preceding specimen ages are provided by Feibel, Brown and McDougall (1989). Note that the published specimen designations do not always correspond in detail with those we encountered on the specimens themselves. Most hominids were found in relatively high-energy stream channels, which explains their generally fragmentary condition. ARCHAEOLOGICAL CONTEXT Mode 1 artifacts are known from sites in Members E and F in the middle of the Shungura Formation (Merrick et a l , 1973), and date to between about 2.4 and 2.3 Ma (Feibel, Brown and McDougall, 1989). There is no positive association with any particular kind of hominid. PREVIOUS DESCRIPTIONS AND ANALYSES In 1967 Arambourg and Coppens reported the discovery of the small but robust edentulous bilateral mandibular corpus (Omo 18-1967-18) which, in a breathtakingly telegraphic report (followed the next year by an only very slightly longer description: Arambourg and Coppens, 1968), they made the holotype of the new genus and species Paraustraloptthecus aethtopicus (though Coppens himself eventually listed this specimen under Australopithecus boisei in 1979, as did Leakey and Walker in 1988). P aethtopicus is a taxon that would probably have been rapidly forgotten but for the fact that, for complicated reasons, it became convenient for others to

USNO)

^0

allocate the robust cranium KNM-WT 17000 from Lomekwi, West Turkana, Kenya, to the species aethtopicus. This Turkana specimen was assigned by its describes (Walker et al., 1986) to A. boisei (though with the comment that the designation A. aethtopicus was available if species distinctiveness were to be shown); today a growing majority (see, e.g., Clarke, 1985; Wood, 1991; Wood, Wood and Konigsbcrg, 1994) prefers the designation Paranthropus (or Australopithecus) aetbiopicus for the Kenyan fossil, and the Shungura specimen must perforce follow. Additional brief descriptions of findings in the Omo by the French contingent of the Omo Research Expedition appeared in a series of contributions by Coppens (e.g., 1970, 1971, 1973a, 1973b). Coppens was generally unforthcoming about taxonomic attributions, but the majority of the comparisons he did make were with Australopithecus Paranthropus robustus [sic] or with Homo babilis. Howell (1968, 1969a, 1969b) briefly described the most important of the hominid fossils collected by the American contingent of the Omo Research Expedition. Comparing the assemblage principally to both gracile and robust Australopithecus from South Africa and to A. boisei from Tanzania, he assigned the robust mandible L7-A-125 to A. cf. boisei and a variety of isolated teeth (mostly from earlier horizons) to A. cf. africanus, while leaving the rest of the sample in abeyance. In 1973 Howell and Coppens published a description of deciduous teeth from the Shungura, and in 1974 an inventory of hominids from the Omo expeditions, both without taxonomic attributions. Boaz and Howell (1977) described the fragmentary cranium L894-1 from high in Member G as early Homo. Howell (1978a, 1978b,1980) later published a more detailed partitioning of some of the Shungura hominid fossils among the species A. africanus (Shungura Members C-F), A. boisei (Members E, F, and G) and Homo habilis (Member G), but the O m o hominid collection has yet to be monographed and the Usno teeth have never been definitively attributed to taxon. In 1978 Rak and Howell described the juvenile cranium L338-y-6, and assigned it to A. boisei—though on the basis of the endocast Holloway (1981) preferred allocation to A. africanus. In 1996 Suvva, White and Howell revisited the O m o Shungura collection and evaluated the lower premolar and molar characteristics of some 55 hominid specimens (mostly isolated teeth, but including seven partial mandibles) scattered through the section from

256

S 1 T K E N T K I IS K

Members H through G.Thcy concluded that all robust specimens from Members C though F (about 2.7-2.3 Ma) represent //. icusy with a "mosaic emergence" of//, bohci during Member G times (to perhaps 1.95 Ma). They perceived no temporal overlap among robust forms. These authors had more difficulty with the nonrobust specimens from Members B and C (about 3.40-2.53 Ma), the bulk of which they considered indeterminate even at the genus level. They accordingly assigned most of them to "/lustrnlopitheats/Homo gen. and sp. indet." In contrast, they found that nonrobust teeth from higher in the section show "phenctic similarities to the early Homo condition" (p. 247), and allocated them to "afY. Homo sp. indet." I lolloway (2000) gives an cndocranial volume of 427 ml for the cranium L.388-y-6. MORPIIOLOGY Although there are two separately catalogued and (inconsistently) numbered Omo fossil samples—one derived from the American explorations and the other from the French ones—all specimens will be described and grouped by morph in a single section below. In the absence of associated upper and lower jaws and dentitions, it is not possible reliably to associate upper and lower dental morphs, although we do make some suggestions based on unique similarities of cusp configuration in upper and lower teeth. We regard the morphs delineated below as provisional, and almost certainly subject to revision in the light of future discoveries of more complete and/or less worn dentitions. We have thus provided extensive individual fossil descriptions. Among the upper teeth in the combined sample it is obvious that there exist distinctly different premolars, distinguishable not only by their discrete overall shapes, but also by distinctive occlusal detail (e.g., compare B8-23A, L726-4 and L338x-35). There arc also distinct upper molar morphs (e.g., compare SI 11-69-17, W8x-753, L50-2 and L398-573). In the lower dentitions, the only preserved cheek tooth in the partial mandible L74-A21, a 1\, is distinctly different in shape and cusp/crest configuration from the P2s of, e.g., L7-A-125, L8-60-2,L427-7 and 75-1969-14A. However, with the exception of L7-A-125 (with its regrettably very worn but clearly very b/1 wide and m/d narrow Ps), it is not obvious in many well-worn cases how or whether to distinguish other lower P morphologies (compare, e.g., the

isolated Pi 751-1255 with the P, in 75-1969-i4A\ The not very worn Pj and the uncrupted and thus u worn P 2 of L427-7 are extraordinarily distinctive! configured, but would they have worn down to look like the Ps in L8-602? Similarly, would the partially preserved, isolated P 2 33-507 have worn down to look like the isolated 33-508 (which seems somewhat comparable to the very worn P 2 of 75-1969-14A), or like the very worn P 2 of L8-60-2? We opt for the former association—of 33-507 with 33-508 and thus with the mandible 75-1969-14A—because of clear, albeit subtle, differences between 33-508 and the isolated PjS represented, e.g., by L398-120 and 18-68-31 and those in mandibles L427-7 and L8-60-2. Although 33-507 is only the lingual half of the crown, it is relatively unworn, and preserves the following features: a less internally placed metaconid that is compressed and incorporated in the cresting system that encloses what would once have been a larger, b/1 wider, and shallower mesial basin; a much thicker and shelflike postcingulid that lies well above the level of the mesial moiety of the tooth and which distends the crown more markedly distally than lingually (originally creating a crown that was m/d longer lingually than buccally); and finely as well as thickly crcnulated enamel. It seems reasonable to associate the isolated Vxs 75i-1255, 33-73-5496 and 123N-5495 because although variably worn they have, for example, the same very mesially truncated and bluntly pointed wedge shape. But while these teeth are remarkably similar in overall shape and cusp detail, they arc clearly not as long m/d or as mesially wide b/1 as the very worn Pi of 75-1969-41, or as short m/d and as distally wide b/1 as the P t of L427-7; and neither is any a match for the Pi in L8-602. Could they instead represent the PjS of the (apparent) hominid represented by L74A21? The root configuration — two stout buccal roots and one d/1 one, producing a triangular shape that tapers mesially—of these isolated P,s is consistent with the preserved roots in L74-A21. But, until mandibles with a P 2 comparable to that seen in L74-A21 arc discovered, this association can only be of the most tentative kind. Another problem that emerges from study of the Ps of this collection is that of recognizing sexual dimorphism. For example, W-97S is a small isolated Pj with the same odd cusp/crest configurations as the b/1 almost twice-as-wide and also isolated L39S-120 and 18-6S-31 (e.g., all have a somewhat mesially placed protoconid, a more mesially and very internally placed metaconid and a thick and lingually

OMO

VAU,RY,

LoWBR (SlIUSOUfcA, USNO)

markedly distended postcingulid). The size disparity
227 Lower Dental Morph (includes 121-73-1950, 136-2, L628-3,628-9, L628-10, L576-27, L64-2, L62-17, L61-2, L51-1, L45-2, L28-31, L7-279, L2-79, L2-89, Ll-398, L795-1,457-35, K7-69-19, B8-28M, W8-752) 227. L juvenile mandible fragment with symphysis through dm2. II crown not fully formed, visible below d i l . Also contains a broken ULP2, the ULC and a molar root. Juvenile mandible fragment with alveoli for d i l - d i 2 and dc. This small mandible is shallow s/i, but thickens rapidly from the distal side of d m l to dm2 and is massive relative to its length. T h e preserved symphyscal region is smooth, and in profile it curves strongly down and back to the inferior margin. Below the dc alveolus the bone is swollen, presumably reflecting the enlarging C crown. Below this swelling the inferior margin bears a low, mounded, roughened

13 i

area. The large mental foramen lies right behind the dc region, and well below the mesial root of d m l . The anterior root of the ramus begins to thicken substantially well below and at the distal end of d m l ; the bone thins markedly infcriorly below this low-set, s/i tall, a/p long and virtually horizontal thickening. There is a long, modestly steep postincisal slope that may have dropped almost vertically into a fossa. More infcriorly, there is some thickening just above the inferior margin. i he dil root was much smaller and more rounded than the rather m/d compressed, b/1 wide di2 root. Both roots were quite short. The dc root appears to have been slightly longer and was more robust and ovoid than the di2 root, dml and dm2 arc b/1 narrow and m/d elongate. The dml is much smaller m/d and especially b/1 than the dm2, the enamel of which was much more extensively wrinkled. The dml trigonid is taller than the talonid cusps, and tapers m/b, the lingual side of the tooth being more obliquely oriented toward the midline than the buccal side, which is swollen by a relatively thick ledge of cingulid that swings entirely around the base of the slightly internally placed protoconid; the crown is somewhat exodacnodont down the mesial root. The metaconid lies a bit distal to the protoconid, but their bases are well melded (thus their cusp apices become distinct high up). A moderate paracristid courses straight down the mesial face of the protoconid, "kinks," and then arcs back to the metaconid, which it ascends; it surrounds a very large and well-excavated trigonid basin. The wedge-shaped hypoconid is the largest talonid cusp and its base extends well across the midline to contact the very small and b/1 truncated entoconid. The somewhat lingually situated d m l hypoconulid is intermediate in size compared to the other talonid cusps. T h e buccal side of dm2 is more swollen than the lingual. All cusps are fairly peripherally placed and somewhat compressed (the metaconid the least), giving the impression of a cresting system circling the crown, enclosing an m/d very long and moderately deep talonid basin. The protoconid and mctaconid are well separated, the former cusp being a bit smaller and more rncsially placed than the latter, which is quite long m/d. A very m/d broad, rncsially rounded and distended and shelflike paracristid courses between the apices of the protoconid and mctaconid. An m/d short and b/1 somewhat truncated, rectangular mctastylid intervenes between the metaconid and the

258

SITE

somewhat small and b/1 truncated cntoconid. The very large, m/d long, and wedge-shaped hypoconid extends well across the midline of the crown and along the entoconid to contact the metastylid. The vcry'buccally placed hypoconulid also extends across the midline of the crown and contacts the entoconid. A triangular, moderately deep and slightly lingually oriented distal depression separates the latter two cusps; the depression is bounded distally by a crest. The enamel is deeply and broadly crenulatcd and there arc vertical grooves along the perimeter of the crown, particularly on either side of the metastylid and in the region of the hypoconid and hypconulid. 121-73-1950. Ldm 2 , virtually identical to the dm2

in 227. L576-27. Relatively unworn Rdm 2 fairly similar to that in 227. It differs in lacking a metastylid and being a bit narrower b/1 across the talonid, but is similar to the latter in such features as its m/d long trigonid basin that is surrounded by a paracristid coursing down and around between the apices of the metaconid and pro toco nid; also, the hypoconid extends across the midline of the crown, along the mesial side of the somewhat b/1 compressed entoconid, which is contacted by the buccaUy placed, m/1 oriented hypoconulid (a crest connects these two cusps distally). L62S-9. L62S-10. L64-2, L62-17. L61-2, L5I-1, L45-2, L2S-31. L7-279, L2-S9, L1-39S, K7-69-19. BS-2SM, W8752. All these are isolated lower molariform teeth (dm2s or Mis) that are similar to the dm2 in 227, especially in having an m/d truncated protoconid, an m/d quite elongate metaconid, a small and b/1 truncated entoconid, a very large and wedge-shaped hvpoconid that courses along the entoconid to contact the metaconid, a buccally placed hypoconid that is oriented m/1 and contacts the entoconid and a relatively thick distal cristid that connects the cntoconid and the hypoconulid, enclosing a basin that separates these two cusps. There is variability in the presence of a metastylid and cingulid around "the base ot the protoconid, as well as in the mesial arcuateness of the paracristid. The less worn teeth have thickly and deeply crenulatcd enamel. 457-35. L lower molariform tooth, similar to those above but larger, lacking metastvlid and cingulid, and with less buccally placed hypoconulid and an m/d shorter metaconid. Its enamel was thickly and deeply crenulated.

ENTRIES

136-2. L molariform, possibly Mx or M f * i worn with damaged metaconid region. Seem conform to the morphology of this group. L795-1. Large, unerupted probably RM3, profusely crenulated, that is relatively wide b/1 compared to it m/d length, and is squared-off mesially and broadly rounded distally. We associate this molar crown with this morph because, size and relative breadth aside it is similar to the other molariform teeth. It has a thick cingulid around the base of the m/d short protoconid and there is a suggestion of a metastylid. Like the other lower molariform teeth, the metaconid is noticeably larger than the protoconid (thus this crown differs from 75-1969-14A in which, although worn the sizes of these cusps are clearly reversed). L628-3. This somewhat worn tooth is essentially the mirror image of L795-1, differing primarily in lacking a significant protoconid cingulid and in having a blunter (less wedge-shaped) hypoconid and a more distinct metastylid. 136-2. Medially broken and worn, but similar to L628-3 and L795-1 in having a distinct buccal cingulid, an m/d thick hypoconid that extends well across the midline of the crown to course along the very b/1 truncated entoconid to contact the distal side of the metaconid, and a shelflike structure wedged between the entoconid and hypoconulid. It differs from these teeth in that the metaconid is not much longer m/d than the protoconid; and the hypoconulid, although coursing obliquely m/1 to contact the entoconid, is not very buccally placed. 12-79. M 3 fragment, probably of this morph. 75-1969-14A Lower Dental Morph (includes 33-507, 33-508,75i-55, L338x-40, L398-1233, L628-4) 75-1969-14A. Two very eroded mandibular corpora. The L side runs from the broken C to the M 3 , the R from C alveolus to the M2. RM3 is congenitally absent. The two sides are apparency reliably associated. All teeth are heavily worn, and some are shattered. This mandible was relatively shallow s/i and narrow m/1, becoming shallower posterior to M l . As seen better on the R, the anterior root of the ramus arises well below M l as a thickening that runs up and backThere seems to have been a mandibular gutter, but apparendy no internal alveolar crest.

O M O VALLEY, LOWER (SIIUNQURA,

As better seen on the R, the Pis had a mctaconid tiutcd opposite and close to the larger and somewhat mcsiallv shifted protoconid. The Pis are longer lineuallv than buccally, the buccal surface being strongly rounded from side to side, somewhat swollen toward the neck and adorned with a modest mesial and a very srnall buccal pillar. A thick postcingulid swells out the Af\ corner of the tooth, which is only minimally distended lingually beyond the mctaconid (thus the crown appears to taper a bit mcsiaUy). There is a small anterior and a somewhat larger posterior fovea. The P2f although slightly larger, is of similar shape to the PI. Taking all Ms together, they are narrow b/1, relative^ long m/d, and roundedly subrcctangular, with the M2s especially rounded distally. All molars arc quite worn; the metaconid is apparently the most prominent cusp on each, and the M2s and the M 3 , especially, show traces of thick crenulation. The M2s, at least, preserve a trace of a wedgelike metastylid at the base of the metaconid. The hypoconulid is somewhat buccally placed on M 1 - M 2 , and very buccally on M 3 . The All is somewhat smaller m/d and b/1 than M 2 ; the LM3 is markedly smaller than the M l . Preserved on the buccal side of L M 2 - M 3 is a short cingulid around the base of the protoconid. 75i-55. Huge-rooted L P 1 resembling those of the 75-1969-14Ajaw. 33-507. Unworn RP2, broken but preserving a very mesially and internally placed metaconid and a thick, lingually distended postcingulid. 33-508, L338x-40, L628-4. All isolated P2s, in various states of wear. Similar to P 2 in 75-1969-14A in general shape, especially in being distended distally with a thick postcingulid terminating on the distal side of the metaconid (not lingually distended with postcingulid terminating on the lingual side of the metaconid, as in L8-60-2). Variation is seen in the m/d truncation of the lingual side. U98-1223. Relatively unworn RP2 lacking buccal portion. Enamel deeply crenulatcd. Thick, postcingulid does not extend much lingually beyond the level of the fairly broad mctaconid. Plausibly represents the less worn state of the P 2 s above. L74-A21 Lower Dental Morph (includes L51-79 andL51-80) L74A-21. R partial corpus, with anterior root of ramus, retaining C and P2, roots of P I and M l ,

USNO)

259

alveolus for 12 and partial alveoli for M2. There is an abnormally wide space between the distal M l root and the alveolus behind it; there is no indication of a M3.Thc preserved teeth arc quite strongly worn. Corpus very tall s/i but only moderately wide m/1. In profile the symphysis was apparently relatively vertical until low down, where it curved back into the inferior margin. The bone under the 12 alveolus is perfectly smooth, as is the bone more posteriorly The large mental foramen lies quite far below the P2. The anterior root of the ramus begins to emerge behind M l , and reaches its maximum thickness opposite the preserved alveoli for M2. More posteriorly, the bone ot the ramus curves inward, suggesting a thinning ramus. The preserved part of the inferior part of the anterior margin of the ramus curves up quite strongly. There is evidence of a modest mandibular gutter. The bone of the inferior margin of the corpus rises smoothly and continuously behind the mental foramen. The postincisal plane behind 12 is fairly steep, and would have been moderately long. Above the midpoint of the corpus the bone descends almost vertically for a moderate distance, and then swells out strongly posteriorly and almost horizontally before curving back down and forward into the inferior margin. In the preserved cross section, there is a massive and s/i deep inferior transverse torus. There is no sign of a mylohyoid line, a digastric fossa, or a submandibular fossa, but posterior to the torus the bone thins slightly toward the inferior margin. As indicated by its alveolus, the RI2 root was short, very wide m/1, slightly compressed m/d, and shallowly grooved, at least on its distal side. The C root would have been the same length, and also of the same b/1 width, as the 12, but is thicker m/d. The C crown curves in slightly relative to the root. The lingual side is concave in profile, and bears a faint mesial margocristid but a thicker distal one. Both converge on a small heel. A low vertical lingual pillar is bounded by a fairly wide but shallow fovea anteriorly, and a shorter but deeper one anteriorly. The preserved C crown is relatively narrow and straight-sided, and would have been quite tall. The P i has three roots, the buccal ones dividing at some point below the neck, but lying in line with one another. The crown would have been shorter m/d than the P2. The P2 is a roundedly rectangular tooth, with a very large and mesially positioned protoconid and a slightly smaller mctaconid that is even more mesially positioned. A oderate paracristid courses high up between the m

260

SITE

midlines of the protoconid and mctaconid, and is delineated behind by a thin b/1-oricnted groove. There is a very thick postcingulid that runs distally from the buccal side of the protoconid around the distal end of the crown (where there is a slight bulbous thickening), then lingually, where it thickens even more markedly into a more cusplike structure behind the base of the mctaconid; this thick crest encloses a deep, m/d long and b/1 wide, subcircular talonid basin. The protoconid and postcingulid arc marked with separate bulges on the buccal side. It appears that there are two closely approximated buccal roots, which are in a/p alignment with one another. The lingual root is slightly distally positioned. The M l roots suggest a crown that was not markedly longer than the P2, and probably not much wider b/1. The mesial roots have two canals, and their configuration suggests that the M l was slighdy broader b/1 mesially than distally. L51-79. RP2, with a somewhat worn, large and bulk)' protoconid and a smaller but taller metaconid opposite. A deep, not very b/1 wide, but somewhat m/d long anterior fovea lies at their bases; the buccal side is strongly sloping*, a thick postcingulid runs from the metaconid distally, swells out the d/1 corner of the tooth and terminates at the side of the protoconid in a vertical buccal groove. The tooth is broadly rounded lingually and is much straighter buccally. The crown was originally quite crenulated. Very similar to L74-A21. L51-S0. RP2; small version of L51-79. L427-7 Lower Dental Morph (includes 18-68-31, 18-68-33,29-68-43,33-73-5496,59/4-68-41, 75i-1255,123N-5495, L8-60-2, L398-120, W-978, B7-39B) L427-7. Partial R juvenile mandibular corpus from P 1 - M 2 . Broken between P2 and M l . Slighdy weathered. PI is almost 2/3 erupted; P2 is in crypt. M l is in place, but its crown is missing; M2 is about half erupted. Lacks bone around the teeth externallv. As expected in a juvenile, the corpus is not very tall s/i, but it is quite broad m/1. No sign of a mental foramen. Internally, level with P i , lies a swelling of bone. No other internal features. The preserved tooth crowns are stronglv cuspulated. P i is smaller in all dimensions than P2." Both Ps have strong buccal pillars terminating in stylids on either side of the low and compressed protocone. O n

ENTRIES

both, a stout but short precingulid arcs from k mesial stylid to a small, very mesially and internal^ placed metaconid. Especially on Pi,'the precingulid encloses a moderate, deep basin that opens d/1 K tween the protoconid and metaconid. On P2 th metaconid is even more mesially placed, swelling th tooth mesially. On PI and P2 another, thicker cristid courses from the metaconid to the midline of the buccal side of the crown, further enclosing the anterior basin, and on P i there is also a third cristid that fills in the region of the basin. On both Ps a stout postcingulid runs from the distal stylid, down around the d/1 corner of the tooth, then up and around to the base of the metaconid, enclosing a relatively deep basin. On P2 the d/1 corner of the tooth is greatly distended, especially d/1, and the enamel is much more densely cuspulated than on P I . The buccal sides of both Ps are strongly sloped, that of P2, with its more centrally placed protoconid, also being more bulbous. On Pi two buccal roots are just beginning to diverge, somewhat below the neck of the tooth. These roots are in alignment m/d. As indicated by the buccal enamel extension on P2, this tooth also would have had two buccal roots. M l has two distinct mesial roots that bifurcate quite low; the distal roots probably did the same. The crown of All was probably smaller b/1 as well as m/d than that of M 2 . M2 is a long, moderately narrow and roundedly rectangular tooth, with subequal protoconid and metaconid lying opposite one another and somewhat forward on the crown. There is a fairly m/d thick, deeply grooved paracristid lying mesially between the internal faces of the bases of the protoconid and metaconid. The hypoconid is the tallest cusp, but is the shortest m/d. The hypoconulid straddles the midline of the tooth, most of it being buccal, and a moderately thin a tongue-like" extension of its base angles m/1 to touch the base of the entoconid distally. The buccal cusps are somewhat centrally shifted, creating a strongly swollen buccal side and constricting the long, narrow, somewhat excavated, and very deeply crenulated talonid basin. There is a distinct upwardly oriented cingulid around the posterior base of the protoconid. In profile all cusps are moderately tall, with distinct notches between them. All cusps are fairly compressed and, were it not for the notches, would form an almost complete ring around the m/d long talonid basin. L8-60-2. Partial mandible lacking rami, most of alveolar region, and the upper part of the symphysis

O M O VALLEY, LOWER (SHU.VGURA,

externally. Vcrv weathered, abraded and partially reconstructed. Retains L P 1 - L P 2 , and RC root, P2*, Ml roots and M2. All teeth are heavily worn. This is a fairly gracile mandible, and is not very lone. Neither is it very deep s/i, or very wide m/L The tooth rows had been somewhat divergent. It appears externally that the symphyscal curvature would have been broader closer to the alveolar margin than further interiorly. The internal symphyscal curve is quite richt. The preserved inferior part of the external symphyscal region is featureless. As seen on the R, the relatively large mental foramen, which lies halfway down below P2, is situated in a broad depression. As seen on the L, the inferior margin of the corpus rises slightly posteriorly. The corpus begins to swell laterally below Ml, with the anterior margin of the ramus becoming risible below M 2 . Behind the M2 the ramus begins to thin strongly interiorly. The postincisal plane is only vcrv jjcntlv sloped, and appears to have been relatively short. High up on the corpus, the midline profile arcs down strongly into a very broad and tall, but not very deep fossa that bears some pitting. T h e floor of this fossa slopes down and back steeply before curving in strongly to the inferior margin, around a moderate inferior transverse torus. Internal corpus features arc not discernible; on cither side of the midline, pointing down, arc two very small, shallow digastric fossae. The anterior teeth apparently occupied a restricted space at the front of the jaw. W h a t appears to be die preserved RC root is very compressed m/d but wide b/l and, as indicated by the two preserved root canals, the root tips diverged some way inferiorly. As seen better on the L, the P I has two relatively long roots. The crown of diis tooth is wider b/l than the P2, but was shorter m/d. T h e apparently very m/d long protoconid region of the RP1 is extremely worn down, but the less obliterated buccal portion shows evidence of a very mesial and internally positioned metaconid, distal to which lies a fairly large and deep fovea or basin that is enclosed entirely by a thick posrcingulid or crest that courses down the preserved distal side of the crown, turns broadly at the d/1 comer ot the tooth, and then courses more or less straight across the lingual side of the tooth to come into the base of the metaconid lingually (cf. P 2 in L427-7), The buccal and lingual sides of the preserved LP2 swell out, the buccal swelling around the protoconid *n& the lingual swelling around a posrcingulid that distended the tooth lingually beyond the level of the niesially positioned metaconid. P2 was longer m/d

USNO)

261

lingually than buccally; the d/l comer of the tooth is swollen distally by a thick postcingulid that runs from the side of the mesially placed protoconid to the side of the subequal metaconid opposite. Both Ps arc more greatly worn lingually than buccally. As seen on the L, P2 has two buccal roots that diverge well below the neck. These roots may have coalesced with the more distally positioned and larger lingual root. As seen on the R, M l roots suggest a tooth that was shorter m/d than the preserved M2. This latter is relatively long m/d and moderately narrow b/l, with very mesially positioned protoconid and metaconid (the latter is truncated m/d) and m/d long hypoconid and cntoconid whose m/d long bases met just lingual to the midline of the crown (cf, hypoconid and cntoconid of M> of L427-7). The hypoconulid occupied most of the posterior end of the tooth, and was probably bifurcated. The d/l comer of the tooth is somewhat distended. 59/4-6S'41* As reconstructed, this is a partial R mandibular corpus extending across the symphysis to the region of L P 1 - L P 2 . Preserved arc broken roots of LC through R P l and M 1 - M 3 . Also preserved is the very worn and broken crown of RP2. O n the L side of the symphysis a piece of bone is glued to the main fragment, but it is hard to say if it belongs where it has been placed. This is a moderately sized but relatively massive jaw that is fairly deep s/i and quite thick m/L The preserved L tooth row was apparendy slightly bowed, and overall the rows were evidently moderately divergent. The inner symphyscal curve is very tight; the outer is slighdy broader. In profile the symphysis descends almost vertically to the raised inferior margin, on to which it curves gendy inferiorly. The upper part of the symphvseal region is essentially straight across. The symphyscal surface bears slight depressions across the region of the incisor roots. Well down the midline is a thin, low but raised area that expands laterally. As seen on the R, this continues at least as far as the level of P I . Also as seen on the R, just medial to the midline, the inferior margin is quite strongly elevated anterior to P 1 - P 2 , reaching its highest point close to the midline. Seen from in front, the symphyseal region tapers slighdy downwards. The very large mental foramen lies midway down the corpus level with P l - P 2 . T h e anterior root of the ramus begins to swell out somewhat below the level of M2, its anterior margin becoming noticeable distal to M2. There was

..:£am national d*I!isto!re Nnlurell utportorrtotit de Ftfhistoire 1,ruoFWnePanfwd

"V 262

SITE

probablv no mandibular gutter. Internally, the only moderately long postincisal plane slopes gently to a point almost halfway down the jaw, where it steepens and contains two small, deep pits. It terminates below these in a superiorly placed inferior transverse torus that quickly thickens laterally. Discernible well below the torus is the R digastric fossa, which is relatively long a/p, posteriorly facing and not very tall or deep. There is no trace of a mylohyoid line, and a large but shallow submandibular fossa lies behind the lateral swelling of the transverse torus. I l - I 2 s roots arc subequal and of moderate size; they are very compressed m/d and are moderately wide b/1. As seen better on the R, the C was relatively more robust and ovoid. Its apparently not very long root swelled out the bone slightly, and probably bore a rather slender crown. The root is in transverse line with the Is. On the buccal side, P 1 - P 2 bear a vertical groove descending from just below the neck, indicating the presence of two close if not coalesced buccal roots. The PI lingual root is quite large, and both teeth are oriented transversely in the jaw. P I would have been slightly shorter m/d than P2, and both were small relative to the Ms. PI was probably shorter m/d lingually than buccally; the reverse applies in the case of the P2, which has a thick postcingulid that swells the tooth lingually in the d/1 corner of the crown beyond the level of the apparently mcsially and internally situated (and large?) metaconid. M l was apparently shorter m/d than M2, and M 3 was at least as long as the M2. M l appears also to have been narrower m/1 than M2. 75i-1255, J23N-5495, 18-68-31, 18-68-33, 29-68-43, 33-73-5496, L398-120, W-978. Isolated P i s , some preserving long, stout, m/d compressed roots with a vertical, variably tall groove along the m/1 surface, creating a V-shaped cross section to the root. The crowns are subtriangular in outline, being distended in the d/1 corner, and tapering somewhat m/b. Protoconids are large and mcsially shifted; the smaller, internally placed mctaconids lie opposite. A thick preprotocristid runs forward and then back up the metaconid, enclosing a deep, moderately swollen basin. A thick postcingulid runs from a stylid-likc swelling on the distal side of the protoconid to the d/1 corner of the crown, then up and forward to the metaconid, enclosing a relatively m/d narrow but b/1 broad basin. The metaconid can lie more mesial than the protoconid and is variably internally placed, hence

ENTRIES

the crown may be less tapering mcsially, and the postcingulid less extensive around the lingual face of the metaconid. Size dimorphism is seen especially i n b/1 width. 177-4525. Uneruptcd RP1 crown that is virtually identical to this tooth in L427-7, but the cusps and crests are not fully thickened by enamel deposition. Paraustralopitbecits acthiopicus Mandibular Morph (includes 18-67-18 and L7-A-125) 18-67-18. Type of Paraustralopithecus aetbiop'tcm. Mandible lacking rami, broken, weathered and repaired in midline. No tooth crowns preserved. Small but massive, almost as wide m/1 as it is tall s/i. The toothrows are markedly divergent, and the anterior curve is roundedly V-shaped both inside and out. Bone of the corpora is basically uniformly thick until, as seen on the R, the anterior root of the ramus emerges lateral to the distal end of M 2 . Below the level of P I - M l , the inferior margin is very slightly elevated, and this margin rises more markedly posterior to the midline of M 2 . Much of the symphysis is missing; it appears from the slightly better preserved L side that the profile descended gently from the alveolar region, curving gradually down from the alveolar to the inferior margin. In the preserved inferior part the symphyscal region is featureless. There is a large R mental foramen lying under the roots of P 1 - P 2 , and a much smaller foramen on the L side that lies further down below P 2 - M 1 . Internally, the almost horizontal postincisal plane is very short, and ends abruptly as the roof of a large, deep and anteriorly extending fossa. As seen on the L, there is a small pit at the anterior end of this fossa, the floor of which bears a small, low midline crest that docs not extend posteriorly on to the large and s/i deep inferior transverse torus. This torus lies some way above the inferior margin, and its inferior surface is undercut by a/p and m/1 extensive and slightly upwardly and back-facing digastric fossae. The posterior margin of the torus bears a moderately broad and deep fossa that is open superiorly and that bears a low, vertical midline crest. There is no sign of a mylohyoid line, but there are shallow and relatively long submandibular fossae that taper anteriorly under the lateral sides of the inferior transverse torus. As seen better on the L, just a trace of the inferior part of the ramus is preserved. It is quite excavated internally, suggesting that the ramus would have thinned posteriorly.

O M O VALLEY, LOWER (SIIUNGURA,

Preserved arc the roots of the R 1 2 - M 2 ; there is a distal root tip glued into the vacant alveolus of LC but it docs not look as if it belongs there. On the L side are broken roots of L P 1 - M 2 . The RI2 root is r rv compressed m/d and short. The RC root is neither long nor particularly bulky, and is somewhat mpresscd. RP1-RP2 have two buccal roots dclinted by a vertical groove; these teeth would have been quite short m/d. M l was shorter m/d than M2; both have two separate mesial roots and one wide distal root. The partial alveolus for M3s is uninformative. L7-A-125. Massive mandibular corpora, weathered but more or less complete except for some damage to external symphyseal region; rami missing. All teeth present except for Lis; all teeth worn and shattered, except for M3s. Jaw massive, tall s/i and even more remarkably thick m/1. Tooth rows are slightly bowed, and diverge slighdy. The inner curve at the front is much more acute than the outer curve, which is still quite tight. Although weathered and somewhat broken, the preserved symphyseal region shows no sign of any distinctive morphology. In profile, the upper part of the symphysis probably bulged very slightly over the anterior tooth roots, then curved smoothly down and back into the inferior margin, which is slightly elevated in the front view. The small L mental foramen lies under the anterior root of P2, about halfway down the jaw, while the much larger R foramen lies under the posterior root at the same level. O n both sides the anterior root of the zygoma takes origin well under M 2 . On the R it appears that there would have been a modest mandibular gutter at best. The bone appears to thicken m/1 more on the R than the L. Internally, the postincisal plane is partly damaged posteriorly, but it was long and moderately sloping. Halfway down the mandible it is interrupted by a large and anteriorly deep fossa that is undercut by the strongly downwardly and forwardly inclined inferior symphyseal plane, whose midline is marked by genial crests that are thickest right below the fossa. The floor of this fossa is ledgelike, and may represent a small, highplaced torus. Internally it is hard to determine any features, except that lateral to the genial crests the interior margin is somewhat crestlike, back to the level of P2. There are slight depressions lateral to the genial crests just above the inferior margin. There was no significant development of the internal alveolar crests around the M3s.

USNO)

263

The anterior teeth are crowded into a very m/d compressed space. The preserved RIs are both very slender-rooted and slender-crowned. Even though the displaced I I is quite worn, it was probably originally quite high-crowned. The C roots are about the same length as the I roots, but are somewhat stouter. The crowns had been small and somewhat compressed m/d. In occlusal outline these teeth present a small, rounded triangle. On its lingual surface the RC shows margocristids that flow into a small, swollen base. By comparison to the anterior teeth, the cheek teeth are huge. P i has very long roots, and those of P2 are even longer. Both Ps have two roots that bifurcate buccally well below the crown. By comparison the molar roots, while quite long, are much shorter. Both Ps are very wide b/1 compared to their length m/d. T h e long axis of both Ps is directly b/1, but the mesial root is more buccally shifted than the distal root. As seen on the R P 1 , the mesial root bears a long, deep vertical groove along its midline, suggesting that it has two apical foramina. P I was somewhat smaller b/1 than P2, and both teeth show very extensive interproximal attrition. The P i s were longer m/d buccally than lingually; the reverse was the case on the P2s. Preserved grooves on the LP2 indicate the presence of a relatively large and mesially positioned metaconid, with a thick postcingulid behind that distends the d/1 "corner" of the crown lingually (creating an obliquely oriented lingual side). Ml—M2 are extremely strongly worn, and are subsquare in occlusal outline. Probably both were originally smaller than the M3s, which were longer m/d than the Ml—M2s and tapered gendy to their rounded distal ends. As seen on the R, the M 3 hypoconulid occupies the entire back end of the tooth, and is subdivided by a crease in its midline. The very large metaconid is quite m/d long, and while the distally displaced and m/d compressed entoconid behind does not extend fully to the midline of the crown, the m/d narrowly wedge-shaped hypoconid opposite extends to touch its base. The protoconid was probably a broad-based cusp, but not as long m/d as the metaconid. The enamel was probably wrinkled. Our association of this mandible with the edentulous 18-67-18 (the holotype of Paraustralopithecus aethiopicus) is a provisional one, based on the fact that both have or had huge cheek teeth, with minuscule anterior teeth crammed into the front of the jaw. Further, in both the Ps appear to have been very b/1 wide and relatively short m/d.

264

SITE

18-68-37 Lower Incisor Morph (includes 18-68-38, 50-3-68-44, and possibly 18-68-40 and F22-2) All of the teeth cited in the section title arc isolated I crowns with some size variation. One preserves the root: it is gracile, only moderately long, and is roundcdly narrowly triangular in cross section, tapering to a fine tip. The mesial side of the tooth is at most gently flared, but is quite tall s/i. The distal side of the tooth flares more strongly, but the edge angles in quickly, truncating the incisal edge of the tooth. All crowns are worn, but all would have been gently convex buccally, and moderately to quite strongly excavated lingually, with moderate to strong mesial and distal margocri'stids. A variably developed vertical lingual pillar lies at or just distal to the midline, with moderately to deeply excavated surfaces on either side. It is impossible to associate this incisor morph positively with other dental morphs, 33-6172 Lower Molar Morph (includes L398-630) We group these two lower molars into a morph distinguished from other O m o lower molar morphs by such features as their set-back and deep trigonid basins, wedge-shaped entoconids and deep basins that are separated by direct contact between the hypoconid and entoconid bases. 33-6172. Partial R (possible) M 3 , missing buccal cusps. Somewhat worn. T h e talonid basin is long, somewhat lingually shifted, constricted and had been thickly crenulated. T h e base of the hypoconid extends across the midline, and a beadlike crest courses from its distal side to the m/d compressed, b/1 somewhat restricted, and wedge-shaped entoconid. T h e metaconid is somewhat longer m/d than the protoconid was. A deep basin lies internal to the metaconid and is separated from a smaller distal basin by the hypoconid-entoconid connection. A thick cristid runs around the tooth from the metaconid to the region of the broken hypoconulid which, judging from the preserved internal aspect of its base, was situated quite buccally. T h e tooth was probably quite broadly ovoid, with a rounded distal end. A distinct and deep anterior fovea or trigonid basin lies noticeably far in from the mesial edge of the tooth, between the broken protoconid and the preserved metaconid. U9S-630. A R (possible) M 3 , lacking the outer perimeter of what had been a quite m/d long metaconid, longer than the protoconid. T h e crown

ENTIUES

was much wider b/1 mcsially than distally • somewhat tightly rounded distally and was probakK at best gently arced across the mesial side. Th'' apparently originally tall cusps are worn flat, but th fairly large basin internal to the metaconid and bounded distally by the hypoconid and entoconid, and the small basin behind this pair of cusps, are both deep and preserve thick or beaded crenulation A cingulid lies along the distal part of the protoconid The rectangular hypoconid extends somewhat across the midline of the crown and contacts the tip of the small, b/1 restricted, wedge-shaped entoconid, which appears to have been incorporated into a cresting system that also included the metaconid. A crenulated notch separates the entoconid from a crest that courses around the back of the tooth to thicken into a very buccally placed hypoconulid that is separated from the hypoconid by a thin groove. The very deep trigonid basin lies well in from the mesial edge of the crown, between the protoconid and metaconid.

Upper Dental M o r p h 1 (includes the specimen below and L726-11) R Maxillary Fragment (no number). Spatially associated with L726-11. Preserved almost from the midline through M l . Partial alveolus for I I , root of 12, alveolus of C, and P I - M l , worn and somewhat damaged. Teeth are large, but the jaw was not long and probably was not very wide across the front. The cheek tooth rows would have been only moderately divergent. Part of the floor of the nasal cavity is present; the inferolateral corner of the aperture is rounded, and the floor of the cavity flows smoothly on to the forwardly sloping and relatively long nasoalveolar clivus. O n the side the floor of the nasal cavity descends smoothly down and back; there was probably not a steep drop in the midline to the cavity floor. Part of the incisive fossa is preserved, as well as part of the canal running forward from it; the posterior pole of the clivus, which apparently tapered posteriorly, markedly overhung the palate, which was very shallow anteriorly, deepening rapidly and smoothly posteriorly. It appears that the superior surface of the clivus sloped gently back to the posterior pole. Externally the clivus appears to descend gently away from the low bulge of the C root, suggesting that centrally the clivus was shallowly concave. T h e C swelling continues laterally over the P I root; and just lateral and

O M O VALLKY, LowBR ( S I I U N G U R A ,

sterior t 0 t j l c Q r o o t is a moderately excavated long, •ertical depression with evidence above and posterior it of the origin of the anterior root of the zygomatic ireh. Thus there is evidence of the inferior part of a canine root pillar, a "canine fossa," and of a zygomatic irch originating just behind P2. The floor of the maxJllirv sinus is preserved, and is subdivided into numerous compartments by low septa. The sinus extends interiorly as far as the level of the C root. As preserved, the sinus docs not swell the wall of the nasal cavirv.The lateral wall of the palate slopes outward. Judging from the alveolus, the root of the II was larcer b/1 and m/d, and probably longer, than the root of 12. Both are compressed m/d. The canine root was cvidentlv verv long, stout and curved down. The root was also quite compressed m/d, and this tooth was probably transversely aligned with the incisors. The cheek teeth are large. Both Ps are very wide b/1 and short m/d. At least the P2 had been slightly broader lingually than buccally. /Ml cheek teeth have very long, stout roots. P I has one root exposed buccally and another lingually. Whether they divided is unknown. P2 shows two buccal roots that become separated close below the neck, but remain close together. The mesial root is more distended buccally. There is one large root surface exposed lingually. The large M l crown was probably roundedly square, with some distension of the huge hypoconc region distally and slightly lingually. The two buccal roots diverge from each other quite close to the neck of the tooth, and both diverged from the large lingual root, which bears a lingual groove down its midline. L726-1I. Unworn RP2 crown, lacking most of paracolic. This tooth was large, and was especially wide b/1. Strongly sloping buccal and distal sides. Paracone swollen, but incorporated into a low, blunt crest that circles the thickly crenulated central basin. Paracolic and protoconc were quite far apart, opening up the basin between them. B8-27 Upper Incisor Morph (includes Ll-1399, L51-5,L571-2) These l i s and I2s arc similar to one another but cannot be associated with other specimens to contribute to a more complete upper dental morph. Their sides do not diverge strongly, and the distal one is only slightly more flared than the mesial. T h e buccal surface is not very convex; the lingual is shallowly excavated, with a series of thin vertical pillars from side to side across its surface. Bulky at base.

USNO)

265

33-740 Upper Premolar Morph (includes 33-3282, 69-900, W-988) These Pis are reasonably similar to one another (and different from L726-11, sec earlier, and 138.4g, see later), but cannot be associated with other upper teeth, with the possible exception of the P2 W-988, which is tentatively included here. The P i s arc relatively short m/d and very wide b/1. Where preserved, the paracolic is centrally placed, with the slightly smaller protoconc more mesial; both cusps are fairly peripherally siaiatcd. The protoconc is incorporated into thick U-shaped cristac, the distal one thicker, which terminate in stylclike swellings buccally on either side of the paracone. There is a long, steep lingual slope. There is evidence of some wrinkling internally on the crown. Anterior and posterior fovcae are wide b/1, thin m/d. A deep horizontal groove runs between the bases of the two cusps. The root was probably widely bifid, as indicated by a groove on the distal side, emanating just belowr the crown. W h a t is preserved of the root is very wide m/1 and compressed m/d. B7-39B Upper Premolar Morph (includes B8-4Q_ and B8-14B) Based on the unworn B8-4Q,, these premolars are unlike others in the sample. BS-4Q. Unerupted LP2 crown. Strongly sloping lingual side with very central protocone. T h e protoconc and paracone have compressed, crcstlikc edges that flow into mesial and distal crests that essentially enclose a deep basin that is V-shaped in profile. It bears some thick crcnulation. T h e tooth is shorter m/d lingually than buccally. The lingual side is bulbous and moderately strongly arced, the buccal side more acutely. There is a conulelike swelling; on the distal crest. B7-39B. LP2 crown, somewhat weathered and worn. Relatively small, shorter m/d buccally than lingually. Both sides are strongly rounded; there are thin mesial and slightly thicker anterior and posterior fovcae; a large bulbous protoconc is separated by a crease from the base of the probably taller paracone. The tooth would have been oriented transversely in the jaw, not obliquely. Probably a worn version of BS-40^ BS-NB. LP2, root broken. Crown very worn. Possibly a worn version of B7-39B, which is in turn a worn version ot B S ^ Q i

266

SITE

B7-39C Upper Molar (nonhominid?) Morph (includes B8-23B, 166-781, P933-1, L28-30, L28-58, L50-2, L51-2, L51-3, L51-4, L51-6, L144-23, L228-35, L238-35, L398-573, SH1-69-17, W8-749, W8-753) These upper molariform teeth (mostly permanent, but some, e.g., SHI-69-17, dm2s) arc discussed collectively inasmuch as given differences in wear they arc reasonably similar to one another and are clearly distinguished from the very worn M l of the unnumbered maxilla (above). This latter tooth is notably wide b/1 relative to its length m/d, while these molariform teeth are somewhat-to-very m/d long relative to their b/1 width. These molariform teeth arc also distinguished from 18-1799, which is roundedly square with a straight and less thick preprotocrista, a thin but defined postprotocrista, a b/1 longer postcingulum and a metaconc that is smaller than the protocone. Allowing for individual variation, these teeth do appear to constitute a distinct morph, albeit one that may not be

hominid. As seen best in the less worn teeth, these upper Ms arc generally distinguished by having tall, bulbous buccal cusps, a large, somewhat centrally placed protocone, subequal and essentially peripherally placed paracone and metacone, thickly crenulated enamel and a hypocone that at least distally is swollen somewhat, and also perhaps lingually. On the M i s and M2s especially, there is a quite deep and open notch between the hypocone and protocone. The preprotocrista, which is thick-to-very thick and ledgelike, swings mesially out and around the tooth along the paracone. The postprotocrista is well-defined and thick, and may appear as a series of conules. A somewhat b/1 short postcingulum emanates from the b/d part of the hypocone and runs around the base of the metacone and up to its tip, enclosing a variably excavated surface. O n the M3s the hypocone is smaller, less well-delineated and may appear as a thickening at the lingual terminus of the postcingulum.

75-14. RM3, somewhat broken, not worn, deeply and thickly crenulated. The protocone is only marginally centrally shifted; the protocristae are long and not very divergent as they run to the paracone and the preserved inner base of the metacone. The trigon basin is thus wide b/1, but compressed. A very thick postcingulum runs from the side of the metacone, thickening toward the d/1 corner, where it curves to join the base of the protocone. There is no

ENTRIES

distinct hypocone. This specimen may fit with those listed immediately above. Unassignable to Morph The fragmentary nature of many of the specimens included under this rubric, as well as the apparent singularity' of others, precludes allocating them even tentatively to the possible morphs suggested earlier. In addition, although we have erected another category to receive certain specimens that appear sufficiently different from the remainder to be regarded as potentially not hominid, it is not impossible that some of the specimens listed in this section, especially teeth that are fragmentary and/or very worn, arc also not hominid. They are listed below in no particular order, although generally similar specimens arc listed adjacently. L55-33. Part of a probable R maxilla, lacking its inferior part, from LI alveolus to RP2. R l - P l represented by roots; I crowns broken, C - P l roots preserved; crown of P2 very worn and broken. Cracked, crushed and weathered. C root bulges slightly. Palate is very shallow throughout. Incisor roots are compressed m/d, subequal in size. C root is not very large and more or less ovoid. P I could have been shorter m/d as well as narrower b/1 than the P2. Two buccal and one large lingual root are preserved; the m/b root is slightly more distended than the d/b. P2 buccal roots diverge slightly high above the neck. The mesial is slightly more distended than the distal; there is one large lingual root. P2 had a large, centrally placed paracone and a very mesially placed protocone. A thick postcingulum runs from what would have been a stylclike structure on the side of the paracone, down and around to the d/1 side of the protocone, swelling the tooth lingually. F22-la. Large R M 3 crown, broken but complete; long and, for its length, moderately m/1 wide; the buccal side was somewhat sloping and the crown tapers gently distally, where it is strongly rounded. Deep grooves exist between all cusps. The metaconid is the largest cusp, the hypoconulid the smallest major one. There is a large subdivided hypoconulid; its larger portion, very buccal, is almost in line with the hypoconid. The smaller portion lies across the midline, next to the entoconid. No cusp bases cross the midline. The enamel was very crenulated, and there was a low, wedge-shaped metastylid at the base of the metaconid, bounded buccally by taint grooves.

EY, L O W E R ( S I I U N G U U A , U S N O )

F203-1. RM 2 , very worn. Very wide m/1 relative to its length m/d. Broadly rounded distally; the base of the hypoconid crosses the midline of the tooth; the hypoconulid is moderately sized, centrally placed and subdivided buccal to its midline; there appears to have been a ccntroconid at the base of the mctaconid (deflecting wrinkle). There also appears to be a wedge-shaped mctastylid at the base of the mctaconid, and a notch between the hypoconulid and hypoconid. There was a probably deep anterior fovea between the bases of the protoconid and mctaconid, and the enamel was probably thickly crcnulatcd. 33-506. Very worn R P \ Three broken roots, two divergent buccally close to crown; the mesial is more in/b situated. The lingual root is much larger than the others. Crown worn very flat; the protocone was probably shifted slightly mesial to the more centrally placed paracone. The lingual side is narrower and more strongly curved than the buccal. 1

L33Sx-35. RP crown, slightly worn. This is a big tooth, m/d almost as long as wide b/1. Longer buccally than lingually; strongly rounded lingually. The protocone is incorporated into peripheral cresting, with stout pre- and even stouter postprotocristae that run either side of the somewhat mesially shifted paracone, ending in stylelike buccal swellings. The paracone is taller than the protocone, with a long internal slope; there is a deep horizontal groove between the bases of the two cusps. BS-23A. LP 1 , missing roots. Slightly worn. Small, with gendy sloping buccal and lingual sides. The protocone is slightly mesially shifted and slightly lower than centrally placed paracone. The cusp edges are somewhat compressed, and run as ridges down to midpoint of crown. The anterior fovea is longer m/d than the posterior fovea. A deep horizontal groove runs between the bases of the cusps. The tooth appears somewhat pinched mesially and slightly bowed distally. There are a few thick crcnulations on the inner surfaces of the cusps. This is the most tfowo-like tooth in this sample. 33-63-1970. RM 3 , very worn. Subtriangular, tapering to its rounded distal side, the buccal side being oblique because of the small metacone. The hypocone does not extend lingually as far as the protocone, and lies directly under the metacone. There *ere stout, thick pre- and postprotocristae, enclosing a somewhat buccallv situated and truncated trigon

267

basin. The protocone was very large internally. The enamel was probably thickly crenulated; there are three distinct roots; the smaller buccal ones are parallel to one another and diverge not far above the neck. The mesial root is more m/b distended. L338x-34. Very worn M2 or M2 crown, with a subsquarc metacone (smaller than paracone); a large hypocone (not distended lingually); and a short, thick postcingulum. Appears comparable to 33-63-1970, just discussed. J8-3. LI 2 , somewhat worn, weathered. The crown curves down strongly on the relatively stout, somewhat roundcdly triangular root. The mesial edge is distended mesially, and the distal edge is rather straight. In profile the buccal surface of the crown arcs strongly down. The lingual surface is only shallowly concave, and bears a slight heel. 755. Probable LI 2 , worn, high-crowned, narrow m/d, with straight buccal side, steeply sloping lingual edge, a broad central pillar and distinct margocristids bounding tall vertical grooves. Root is compressed. 20-4.70-272. LCj somewhat worn, with relatively long, gendy sloping mesial edge and a subequal but much more steeply oriented distal edge that swells at its distal terminus into a moderate heel that is accentuated buccally by a vertical pillar, and that is cut off lingually from a lower basal swelling by a thick pillar that courses from the latter to the tip of the crown. On either side of this lingual pillar is a deep, vertical, lingually facing fovea, of which the anterior is the larger. There is also a buccal pillar along the mesial portion of the tooth that is delineated along its distal margin by a vertical groove. The lower part of the very stout and round root is missing; the crown appears somewhat small relative to the bulkincss of the root. 25-79. Fragment of lower RM crown, unworn. Preserved buccal and lingual cusps arc compressed and peripheral; an m/d short, creaselike fovea runs between the mesial bases of the mesial cusps; the broad, moderately shallow talonid basin is deeply and thickly crenulated, and partially cuspulated. L49-1. Distal lower LM fragment, moderately worn, hypoconulid not folly buccal, with a shallow notch between it and the hypoconid. L824-5. Relatively small, moderately broad and rectangular LM! or M 2 . Worn very flat. Large

268

SITE

wedgelike mctastylid at base of metaconid; hypoconulid just buccal to midline; stout mesial and distal roots had bifurcated some way below neck. Cf. 75s-69-16. 75s-69-16. Very worn small lower RM crown that had been thickly cuspulated. Moderately elongate ovoid, gently tapering distally. Wedge-shaped mctastylid-Iike structure at distal base of metaconid. Base of hypoconid crosses midline; moderate hypoconulid, somewhat buccally situated. Cf. L824-5. 195-1973-1630. Very worn RM, or M 2 . Small, relatively long m/d and narrow b/1, with very long and stout roots. The mesial root bifurcates at its tip more strongly than the distal roots, which are very large compared to the crown. There is a distinct notch between the metaconid and the hypoconid, and a much weaker notch between the entoconid and the not as buccally placed side of the hypoconulid. 47-68-45. Worn fragment of lower L M 1 or L M 2 . o

Notch between quite buccally placed hypoconulid and entoconid, and possible protostylid. 33-69-10. Worn fragment of L M 3 crown. A very b/1 wide hypoconulid occupies most of the distal end of the tooth. The hypoconid is compressed m/d, and its base goes across midline. Cf. 47.1968.46. 47.196S.46. Broken and very worn crown of M2> with very broad, almost rounded look. Wider m/1 mesially than distally; the hypoconulid occupied almost the whole back end of the tooth; the base of the hypoconid extends across the midline. Cf. 33-69-10. 76-69-11. Buccal half of R possible M 3 crown. Very worn and somewhat weathered. Had been thickly crenulated. There is a thick cingulid around the protoconid that runs up the side of the hypoconid, and a trace of cingulid on the distal side of the hypoconulid. This had been a long, ovoid tooth that tapered distally. L398-1699. RC 1 crown, root broken. Moderately worn. Root would have been stout, especially b/1. In profile, buccal and lingual surfaces are strongly divergent toward neck. Rather narrow m/d, with buccal surface gently convex and rather vertical; lingually a mesially placed pillar swells into a basal tubercle. Distinct mesial and distal margocristac bound a thin mesial and broader and shallower distal depression.

E NTKI ES

44-70-2355 (P 717, 27.6.70). Fragment of inferior L corpus. A relatively thick, apparently not very tall jaw. 141.72.167. Small cranial fragment, quite thickboned. 141.72-4. Small thin-boned cranial fragment. 33-63-1970. A RM 3 , quite worn. Triangular, tapers distally. The protocone is large and rounded, probably internally placed. The paracone also large with a large distal internal slope that terminates at the base of a very thick, conulclike postprotocrista; the preprotocrist'a apparently swung far mesially to come around the paracone; the mctacone is small, obliquely truncated, and m/d compressed; the hypocone is swollen greatlv distally, but its lingual side is quite buccal to the level of the protocone, from which it is separated by a deep groove on the distal side of that cusp; a very thick postcingulum emerges from the d/b side of the hypocone and arcs mesially to the distal side of the metacone. Two buccal roots, close together. 195-1973-1630. Extremely worn RM, or M 2 . 75s-69-58. L M , or M 2 , quite heavily worn but with very long mesial and distal roots that diverged close to the neck, and that may have been bifid at their tips. The moderately sized and wedge-shaped hypoconulid lies in the midline; the base of the hypoconid extends across the midline lingually. There was probably a notch between the hypoconid and the cusps on each side. The crown is small relative to the size of the roots, and the tooth is roundedly rectangular. F203-1. Very worn RM 2 . Hypoconulid twinned. 141-2. Fragment of a large crenulated M. 141-1. Thickly crenulated broken; reminiscent of 33-65.

lower

M

crown,

20.4-70-272. Lower LC. The lower half of what would have been a very long root is broken; the root is stout relative to the crown. The crown is roundedly and narrowly triangular in outline, being flatter on its mesial side. The crown is relatively narrow, and would have been moderately tall, with a short, almost horizontal mesial edge and a long, steeply sloping distal edge terminating in a swelling. There is a thin mesial and a thicker distal pillar on the buccal side; the distal pillar flows into the distal heel, from which.

O M O VALLEY,

LOWER

on the lingual side, runs a short, thick margocristid that flows into the base of a lingual swelling that continues up the lingual surface of the crown as a oillar that lies distal to the midline of the tooth. T h e pillar and the margocristid subtend a deep, vertical, wedec-shaped depression. Mesial to the pillar the limrual surface is shailowly but much more expansively excavated. Tentative positive comparison with Maka VP 1/12. 141-72-123. Broken, long-rooted, upper I. 18-68-36. Very worn LI 1 . Very short, rapidly tapering root. Crown is straighter on the mesial side, with a moderately marked flare distally. Buccal side is ecntly convex. Wide b/1 at base. J8-6S-39. RI 2 . Very worn, root broken, mesial side slightly divergent; distal side more vertical. W i d e b/1 at base. 74-69-18. Unerupted crown of RP 2 . L338x-33. Fragment of a large upper R 18-68-35, 33-64, 33-72-31, 35-4022, 47-20, 3362.1970, 57.5-123, 50.5-370, 57.5-197, 57.5-372, 33-3721, 33-509, 33-3495, 33-3282, 33-40-4024, 33-3325, 75-14-B, 75-14b, 141-69, 44-1410 (1970), 57.4-147, 57. 4-148, 57.5320, 76-38, W8-750, W8-751, W7-578, Ll-611, Ll-667, L28-2Sx, L1S3-11, L209-15, L209-30, L338x-32, L54-20, L136-9, 144-24, L28-126, L398-1215, L398-2230, L9-92, F22-1A, F22-1B, 76-69-12, LSSO 2a.b., L797-1, L628-7, L628.8, L39S-2626, L398-2627, L465-112, L465-113, F183,141-72-123. Uninformative tooth fragments. Other Nonhominid 141-72-117, 118, 158. Cranial fragments glued together to make part of a R parietal with lambdoid and sagittal sutures, and a sagittal crest emerging. 141.72.177. Fragment of maxilla, with part of palatine groove. Also six other small, uninformative pieces. u

20.1.1886 (aka 20.1.1773.18S6). Fragment of an

Pper LI. L296-1,33-4000. L M 3 .

b

L209.18. Dental fragment. T h i c k enamel, broken unodont cusps. L880 la-d.

Upper M fragments. T h i n enamel.

(SIIUNGURA,

USNO)

269

L704-2. Fragment of suid dm 2 . 76-37, 47-1500, 84-100. 33-6172. 141-1, 33-65. 57244-5. 47-1500, 76-37 {large version of 47-1500,) 84-100 (similar to 47-1500 and 33-61.72). All are bear molars (Agrotherium). 47-68-47, 28-68-30 and 33-69-9. All are M 3 s with large, very long, tapering ovoid outlines. All heavily crenulated and cuspulatcd; probably representing a single wear sequence. Unworn, the cusps are low but distinct, with bulbous bases, and are set peripherally, opening up the m/1 wide and moderately shallow talonid basin. T h e hypoconulid is large, occupying the distal end of the tooth, and is variably subdivided. Cingulid around the m/b cusps. O n each side there are multiple cusps arranged in a peripheral row. Roots are thick and stout. Ursid (?). L10-21 and L398-847. Fragments of otter (?) molars that have been prepared for thin-section analysis of enamel thickness. L628-2. Large, chunky molar crown. 76-69-13. Broken L M 3 crown. 57-68-42. Slightly worn lower molar fragment; very bulbous cusps separated by grooves, filling in the central basin. Probably not hominid. 18-1799. Upper L M , possible M 1 or M 2 , with compressed crown and splayed roots. Roundedly square with a straight and less thick preprotocrista, a thin but defined postprotocrista, a b/1 longer postcingulum, and a metacone that is smaller than the protocone. 136-1. Broken but complete unerupted probable L M 3 . Ovoid, moderately broad, tapers distally. T h e four primary cusps are quite compressed, internally set and incorporated in a cresting system that runs mesially from the hypoconid around to the entoconid. T h e more distinct hypoconulid spans the back ot the tooth but is short rn/d. The buccal side bears a thick cingulid that runs down from the mesial face of the protoconid, across the groove between this cusp and the mctaconid, then almost vertically up the side of the metaconid. Another wedge-shaped cingulid runs down the distill side of the hypoconid and up to the hypoconulid. Internal to aU cusps the enamel is thickly crenulated and cuspulated. In many ways, very Pongo-Wke.

270

SITE

L398-2608. RM 3 , roots missing. Lingual root strongly projected away from the crown. Buccal side strongly sloping; mesial and lingual sides less so. Cusps not distinct, being compressed into a cresting system that rings the tooth, enclosing a shallow basin that is broadly and deeply crenulated and cuspidated. Probably not hominid. L9-12. Is similar to L398-2608 in shape, but larger, with a more distinct hypocone and protocone. 126-59. Upper M fragment, heavily crenulated, probably goes with L9-12 and L39S-2608. All are somewhat orangutan-like. 1S-6S-32. Part of an RM'(?). Worn, very thin enamel. Lingual side bulbous; protocone centrally shifted; stout protocristae run to buccal cusps enclosing small, constricted basin; large bulbous hypocone swells d/1 corner of tooth distally; a short, moderately stout postcingulum runs to the side of the metacone, which is smaller than the paracone. 166-781. Very worn M 3 . Orangutan-like. L338x-39. Long, narrow, mesially rounded LM3 crown, with parallel rows of bulbous lingual and buccal cusps that are delineated in the midline by a deep groove that runs the full length of the tooth, and on their sides by thinner grooves. Cf. 33-69-9 and 2868-30. L39S-266. Worn RM 3 . Plausibly nonhominid. Huge tapering distal root formed by the confluence of three smaller roots. B8-14A, U20-15, L465-11, L62S-1, L628-5. Teeth with subcircular occlusal oudine. A thick, creased postcingulid runs around the sides of the protoconid and metaconid, swells the d/1 corner of the tooth, then goes around the base of the metaconid, proceeding up the mesial side of the tooth. The distal sides of the protoconid and metaconid, and the inner side of the postcingulid, slope steeply down to produce a deep basin. Just distal to the apices of these cusps is a deep fovea. Mesially the faces of the cusps and the cingulid in front form a deep fovea. Apparendy a giant otter. W7-591. Fragment, probably not hominid. 18-68-34. Unworn lower LM crown. Highcrowned, with distinct bulbous cusps and somewhat sloping buccal and very sloping lingual sides, so the

ENTRIES

cusps constrict the deep central basin laterally a A somewhat m/d. There is a very deep, moderately m/A long fovea mesial to the bases of the protoconid and metaconid. A moderately large hypoconulid lies almost buccally in line with the hypoconid, and just at the d/1 base of the entoconid lies a small, pointed cuspulid. The protoconid and metaconid are quite close together, the entoconid and hypoconid are much farther apart. A buccal cingulid runs from the midpoint of the protoconid just to the mesial side of the hypoconid. This is a roundedly rectangular moderately elongate tooth that is slightly distended in the d/1 corner. Probably not a hominid. However teeth such as this wear down to look more hominid than they actually are. L26-1G. RM l f a smaller version of 18-68-34. L2S-30. LM 3 crown, unerupted, weathered, relatiely small. Long, narrow, gendy tapering, broadly rounded mesially, strongly rounded lingually, deeply crenulated. Four major cusps in mesial and distal pairs, and a broad, buccally shifted hypoconulid.

REFERENCES Arambourg, C. and Y. Coppens. 1967. Sur la decouvertc, dans le Pleistocene inferieur de la vallee de l'Omo (Ethiopie), d'une mandibule d'Australopithecien. C R. Acad. Set. ParisDt 265:5S9-590. Arambourg, C. and Y. Coppens. 1968. Decouverte d'un Australopithecien nouveau dans les gisements de l'Omo (Ethiopie). S. Afr.J. Set. 64:58-59. Boaz, N. T. and F. C. Howell. 1977. A gracile hominid cranium from Upper Member G of the Shungura Formation, Ethiopia, ./foi./. Phys. Anthropol. 46:93-10S. Brown, F. H. 1969. Observations on the stratigraphy and radiometric age of the "Omo Beds," lower Omo basin, southern Ethiopia. Quaternaria 11: 7-14. Brown, F. H. et al. 19S5. An integrated Plio-Plcistocene chronology for the Turkana basin. In: E. Delson (cd.)y Ancestors: The Hard Evidence. New York: Alan R. Liss, pp. 82-90. Clarke, R. J. 1985. Australopithecus and early Homo in southern Africa. In: E. Delson (ed.), Ancestors: The Hard Evidence. New York: Alan R. Liss, pp. 171-177. Coppens, Y. 1970. Les restes d'Hominides des series infcrieures et moyennes des formations plio-viUafranchiennes de TOmo en Ethiopie. C. R.Acad. Sri. Paris D, 271: 2286-2289.

O M O VALLEY, LOWER (SIIUNGUUA,

Coppens* Y. 1971. Les restcs dTIominidcs des scries supericures des formations plio-villafranchicnnes de TOmo en Ethiopic. C. R. Acad. Scu Paris D, 272: 36-39. Coppens, Y. 1973a. Les restes d'Hominidcs des scries infcricures ct moyenncs des formations plio-villafranchicnnes dc TOrno en Ethiopie (rccoltcs 1970, 1971 ct 1972). C. R.Acad. Set. Paris D, 276:1823-1826. Coppens, Y. 1973b. Les restcs d'Hominides des scries supcricures des formations plio-villafranchiennes de TOmo en Ethiopie (rccoltcs 1970,1971 et 1972). C. R.Acad. Sci. Paris D, 276:1981-1984. Feibel, C , F. Brown and I. McDougall. 1989. Stratigraphic context of fossil hominids from the Omo Group deposits: Northern Turkana Basin, Kenya and Ethiopia. Am. J. Phys. Anthropol. 7%: 595-622. de Heinzelin, J. 1983. The Omo Group. Ann. Mas. R. Afr. Cent, ScL Geo!. $5:1-365. Howell, F. C. 1968. Omo research expedition. Nature 219: 567-572. Howell, F. C. 1969a. Remains of Hominidae from Pliocene/Pleistocene formations in the Lower Omo Basin, Ethiopia. Nature 223:1234-1239. Howell, E C. 1969b. Hominid teeth from White Sands and Brown Sands localities, lower Omo Basin (Ethiopia). Quaternaria 11:47-64. Howell, R C. 1978a. Hominidae. In: V. Maglio and H. B. S. Cooke (eds.), Evolution of African Mammals. Cambridge, MA: Harvard University Press, pp. 154-248. Howell, R C. 1978b. Overview of the Pliocene and earlier Pleistocene of the lower Omo basin, southern Ethiopia. In: C. Jolly (ed.), Early Hominids of Africa. London, Duckworth, pp. 85-130. Howell, R C. 1980. Origins and evolution of African H o minidae. In: J. D. Clark (ed.), The Cambridge History of Africa, Vol. 1. Cambridge, UK: Cambridge University Press, pp. 70-156. Howell, R C. and Y. Coppens. 1973. Deciduous teeth of Hominidae from the Pliocene/Pleistocene of the lower Omo basin, Ethiopia./. Hum. Evol. 2:461-472.

USNO)

271

Howell, F. C. and Y. Coppens. 1974. Inventory of remains of Hominidae from Pliocene/Pleistocene formations of the Lower Omo Basin, Ethiopia. Am. J. Pbys. Anthropol. J 40:1-16. Holloway, R. L. 1981. The endocast of the Omo L.336y-6 juvenile hominid: gracile or robust Australopithecus? Am. J. Phys. Anthropol. 54:109-118. Holloway, R. L. 2000. Brain. In: E. Dclson ct al. (cds.), Encyclopedia ofHuman Evolution and Prehistory, 2nd ed. New York: Garland Press, pp. 141-149. Kimbel, W. H., T. D. White and D. C. Johanson. 1988. Implications of KNM-WT 17000 for the evolution of "robust" Australopithecus. In: F. E. Grine (ed.), Evolutionary History of the "Robust" Australopithecifies. New York: Aldine de Gruyter, pp. 259-68. Leakey, R. E. R and A. C. Walker. 1988. New Australopithecus boisei specimens from East and West Lake Turkana, Kenya. Am. J. Phys. Anthropol. 76:1-24. Merrick, H. et al. 1973. Archaeological occurrences of Early Pleistocene age from the Shungura Formation, Lower Omo Valley, Ethiopia. Nature 242: 572-575. Rak, Y. and R C. Howell. 1978. Cranium of a juvenile Australopithecus boisei from the Lower Omo Basin, Ethiopia. Am. J. Phys. Anthropol, 48:345-365. Suwa, G.,T. D. White and R C. Howell. 1996. Mandibular postcanine dentition from the Shungura Formation, Ethiopia: crown morphology, taxonomic allocations, and Plio-Pleistocene hominid evolution. Am. J. Phys. Anthropol. 101:247-282. Wood, B. A. 1991. Koobi Fora Research Project, Vol. 4: Hominid Cranial Remains. Oxford: Oxford University Press. Wood, B. A., C. Wood and L. Konigsberg. 1994. Paranthropus boisei: an example of evolutionary stasis? Am. J. Phys. Anthropol. 95:117-136.

Repository National Museum of Ethiopia, PO Box 79, Addis Ababa, Ethiopia.

272

SITE

£snr ROBES

O M O Figure 1. Partial R maxilla, uncatalogiicd (scales

s

1 cm).

273

OMO VALLEY, LOWER (SHUNGURA, USNO)

OMO Figure 2. Lower molars. On L, 8-68-34; on R, L26-lg (scale

t cm).

OMO Figure 3. Upper premolars. From L to Rs B138-4g, B7«39B» B8-14B (scale » 1 cm)*

01

NUMIVN&

OMO Figure 4« 11 X upper L12, Ungual a»d buecikl view* (welt«-1 tnu)i

274

SITE

ENTRIES

O M O Figure 5 18-67-18, partial mandible (scales = 1 cm).

O M O Figure 6. 18-17-99, upper L molariform (scale == 1 cm).

i

OMO VALLEY, LOWER (SHUNGURA, U S N O )

275

... 4 • 1

as v**

* 1

OMO Figure 7. Lower molars. Top L: 33-65; Top R: 141-1; Bottom L: L628-3; Bottom R: L 795-1 (scale = 1 cm).

'

OMO Figure 8. Lower P2s. L: 33-508; R: 33-507 (scale = 1 cm).

OMO Figure 9. Lower molars. From L to R: 36-69-9; L338x-39; 28-68-30 (scale = 1 cm).

276

S I T E EKTXIES

Mm

i

^B tin

^r / V kJ^S^m

n^i

t/^ w^^^Ss^-^^^^^^^^8

^s^^^^^^L

pp"!Bflg j^OTwK

w ^&£&£-J&

HH

.

£j? :

i

OMO Figure 10. 59/4-68-41, partial mandible (scales = 1 cm).

•A^~~^B|

#•«u

(Nil

O M O Figure 11. 75-1969-14A, R and L partial mandibular corpora (scales - 1 cm).

m

278

SITE ENTRIES

i

|w

EPSlMf ^•rnJ'ifT* j3^B

ill]

l

rcBi

H > ' •£?•; i*-«6^Btl^H i IfrSrwI JgjKtfy iMfl

^F^^HM^a^3 •HI rfff'^i

Ex, « • R

fl

OMO Figure 12. Lower Pis. In both composites, from L to R: 75i-1255,123N-5495,33-73-5496 (scales = 1 cm).

OMO Figure 13. Lower molars. From L to R: 81-100, 76-37,47-1500 (scale = 1 cm).

OMO Figure 14. On L: 121-75-1950, lower Ldni2; on R, 227, partial L mandibular corpus (scale = 1 cm).

O M O VALLEY,

LOWER (SHUNQURA,

OMO Figure 15. Lower molars. L column: 136-1; R column: 136-2 (scale = 1 cm).

USNO)

279

O M O Figure 16. Upper molars. Top L: 166-781; Top R: P933-1; Bottom: 33-63-1960 (scale = 1 cm).

O M O Figure 17. 195-1973-1630, lower molar (scale -

280

SITE

ENTRIES

O M O Figure 18. 227, partial L juvenile mandibular corpus (scales = 1 cm).

O M O VALLEY, LOWER (SIIUNGURA,

USNO)

O M O Figure 19. 20.4.70-272, lower LC (scale \ = 1 cm).

O M O Figure 20. Lower mol

ars. Left: F22-1A; Right: F203-1 (scale 1 1 cm).

281

282

SITE

ENTRIES

O M O Figure 2 1 . L7-A-125, partial mandible (scales = 1 cm).

O M O VALLEY, L O W E R ( S H U N G U R A ,

USNO)

O M O Figure 22. L8-60-2, partial mandible (scales = 1 cm).

283

284

SITE

O M O Figure 23. Upper molars. Top row, L to R: L502, L51-2, L398-573; Bottom row, L to R: L238-35, L51-3, L28-58 (scale = 1 cm).

k

ENTRIES

O M O Figure 24. Upper molars. Top L: L51-4; Top R: L50-2; Bottom L: L51-2; Bottom R: L398-573 (scale = 1 cm).

O M O VALLEY,. LowisR (8UUNGURAV HTSKO)

OMO Figure 25. Upper lis, lingual (above) and buccal (views. L column, L51-5; Middle column, Ll-1349; R [column: L571-2 (scale = 1 cm).

O M O Figure 26. Upper molars. 12; L398-2608 (scale = 1 cm).

285

286

SITE

O M O Figure 27. L55-33,. R partial ngnTTa (scale = lcm).

ENTRIES

O M O Figure 28. Lower molars Top L: L64-2;Top R: 151-1; Bottom L: L2-89; Bottom R: L45-2 (scale =

Ian).

r

O M O VALLEY, L O W E R ( S H U N G U R A ,

USNO)

287

OMO Figure 29. Upper premolars. Top L: L68-23A; Top R: W988; Middle L: L726-11; Middle R: L338x-35; Bottom L 33-740; Bottom center: 69-900; Bottom R: 33-3282 (scale = 1 cm).

288

S I T E ENTRIES

' i

*c

i;jy3S5fti 1

-'-a^K^^I

\f!-* -V

•^^^

^H

^W1

O M O Figure 30. L74-A21, partial R mandibular corpus (scales == 1 cm).

O M O VALLEY, LOWER (SHUNGURA,

USNO)

OMO Figure 30. (Continued).

289

290

SITE

OMO Figure 31. Lower premolars. Top row, L to R L398-120; 18-68-31; W987. Middle row, L to R L338x-40; L28-4; L398-1223. Bottom row, L to R L51-79; L51-80 (scale = 1 cm).

ENTRIES

O M O Figure 32. Top row, L to R: L398-630; L28-30, lower molars. Bottom row, L to R: L704-2; L576-27, lower dm2s (scale = 1 cm).

OMO Figure 33. L398-1699 upper RC (scale = 1 cm).

O M O VALLEY, LOWER (SHUNOURA, U S N O )

OMO Figure 34. L427-7, fragmentary R mandibular corpus (scales = 1 cm).

291

292

SITE

ENTRIES

O M O Figure 35. Lower molariforms. Top row, L to R: L628-9; K7-69-19. Bottom row, I (scale = 1 cm).

j L62-17; 457-35

O M O Figure 36. Lower molars, L to R, showing wear series: L628-10; L628-9; K7-69-19 (scale = 1 cm).

OMO VAI,LV,Y,

Low

en (SHUXGVUA,

U»»O)

OMO Figure 37. Upper molars. Top row, L to R: SHl-69-17; L51-4. Bottom row, L to R: W8x-753; L144-23 (scale = 1 cm).

PENINJ

(Lake Natron)

LOCATION Exposures in dry wash of Peninj River, W of Lake Natron, northern Tanzania, some SO km NE of Olduvai Gorge (Map 3). DISCOVERY Kamoya Kimeu, 11 January 1964. MATERIAL Mandible with full dentition, missing most of L ramus.

DATING AND STRATIGRAPHIC CONTEXT Lake delta sandstones of the lower Humbu Formation, bracketed by volcanics dated at 1.7 Ma below and 1.3 Ma above (Isaac, 1967; Isaac and Curtis, 1974), a dating consistent with paleomagnetic determinations (Thouveny andTaieb, 1987). ARCHAEOLOGICAL CONTEXT Humbu localities later than the hominid site have yielded early Acheulean industries, including bifaces and cleavers (Isaac and Curtis, 1974). There is no evidence to connect the artifacts with any particular kind of hominid, and there is no association between the one hominid known and any artifact-yielding horizon. PREVIOUS DESCRIPTIONS AND ANALYSES The discover}' of the hominid mandible was announced briefly by Leakey and Leakey (1964), who

hailed it as an "unmistakable australopithecine,* bv implication a counterpart to their "Zinjanthropus* cranium from Olduvai (OH 5). In a perhaps surprisingly sparse literature on the Peninj mandible, nobodv has since seen fit to take exception with the assignment of this specimen to Australopithecus (or Pawntbropus) boisei. MORPHOLOGY

NMT WN 64 160. Almost complete mandible lacking L coronoid and condyle, R coronoid and R gonial region, but preserving entire dentition. Except for M3, the teeth are fairly heavily worn. On the R, enamel is completely gone from the Ml and P2 metaconid and protoconid regions; on the Ml from the hypoconid region; on the M2 from the protoconid region. On the L, enamel is missing from distal side of PI and the buccal sides of P2-M2. As reconstructed, the Is are glued in at a higher level than teeth distal to them, and may be in the wrong order (R and LIls may have been switched). The rami greatly reconstructed. Robust mandible, corpus thick b/1 and tall s/i. The symphyscal region is taller s/i than the region of the M3 (thus the corpora get shallower posteriorly). The symphyscal region is slightly undulating m profile: a slight depression lies under the I roots (especially the I2s), then a taint bulge carries on down to inferior margin (i.e., there is a slight depression below the Is, centrally). Seen from above, the symphyscal region has a moderately tight curve; the corpora

294

I'EN'IXJ ( L A K E

tinue to diverge out and away from the less diver' t check tooth rows. Also from above, the Is and Cs frm a flat curve across. The postincisal plane is slopnjr and moderately long; it drops off sharply quite I Vli up to curve around and forward again into very jeep and large twinned genial pits that are separated from one another by a crest that continues back and down over the well-defined inferior transverse torus. Infcriorlv, two tiny digastric fossae are set far back and face postcrioinfcriorly. On the R, a large mental foramen lies below P2-M1, level with the origin of the anterior margin of the ramus. On the L are two slightly smaller mental foramina. The anterior foramen lies below the posterior root of P2, level with the rise of the ramus. The posterior foramen is more inferiorly situated, aligned with the septum between P2 and M l . The external surface of the ramus is long a/p; for the length of the corpus, it is not especially tall s/i and it is remarkably smooth. The mandibular gutter, formed by the rise of the ramus, is fairly marked. The anterior margin of the ramus takes origin below the level of the posterior part of the M2 and rises moderately steeply, obscuring most of the M 3 in profile. The very end of the sigmoid notch crest is preserved on the R and terminates just inside the lateral extremity of the coronally arcuate, a/p compressed condyle (thus most of the condyle lies medial to the crest). The bone thins markedly inferiorly at the gonial region, which is smoothly curved in profile with fairly low and localized muscle scars along the inferior margin externally. The internal alveolar crests arc well defined and very posterior, and swing laterally behind the M 3 to enclose the mandibular gutter before rising posterosuperiorly and dividing to send low, thick pillars to the condyle and the coronoid peak. There is no discernible mylohyoid line. The submandibular fossae under the M2 region arc very shallow and poorly denned. R and L mandibular foramina point up and back; they lie below the bifurcations of the internal alveolar crests, and just above the level of the M crowns. The L foramen is ovoid, the R is more compressed and is partially covered by short lingula. A series of five low internal pterygoid swellings lies on the gonial margin posteriorly, from the inferior margin to above the level of the mandibular foramen. t0

Hie Is arc tiny, and were probably not very tall in their unworn state. The I2s flare laterally more noticeably than the l i s . All Is have fairly pinched necks and Modestly concave lingual surfaces, with small inferior

NATUON)

295

swellings. The 1 roots are stout, not long. The C crowns are narrowly conical, not very tall; the roots arc very long, relatively stout. Lingually, as seen especially on the L, low margocristids bound shallow depressions and a very small lingual heel. The Pis are quite worn, chipped and arc almost as wide b/1 as, but are much shorter m/d than, the P2s. As seen on the L, P i has two lingual roots that bifurcate just below the crown. The PI mctaconid region lies opposite to, and is at least as large as, the protoconid region. Both cusp areas arc mcsially positioned (thus the distal moiety of the crown is larger than the mesial). The P2s arc slightly shorter m/d on the buccal than the lingual side. Particularly on the L, the P2 is subcircular in occlusal outline, and is swollen d/1 by a well-developed entoconid region. The P2 mctaconid and protoconid regions arc subequal in size, and lie opposite each other. The P2 hypoconid region is the smallest, and the P2s are probably tworooted. On both sides there is some destruction of the alveolar crest buccally, starting at PI and becoming more intense toward and around M 3 . M l is shorter m/d than M2 and M3. M 3 is narrower b/1 than M l , which is slightly narrower than M2. All Ms lack cingulids; the M 3 enamel is moderately crenulatcd, producing small internal cuspulids. The M i s are subcircular, although a little longer m/d than they arc wide b/1. On M 1 - M 2 , the protoconid and mctaconid regions lie opposite one another, and arc situated very mcsially. The unworn M l and M2 probably lacked trigonid basins of any sort. M 1 - M 2 cntoconids and hypoconids lie opposite each other and are somewhat mcsially placed. The hypoconulid regions are quite large, and arc especially wide b/1. The hypoconulid apex is not as buccally placed as the hypoconid. Lingual to the hypoconulid, at the midline of the crown, is a small, flatly worn, cusplike structure. M3s arc relatively little worn and arc rectangular with rounded corners. M 3 cusps arc low, relatively indistinct. The lingual cusps are peripherally placed, the buccal cusps are more internal (thus the long, shallow, talonid basin is offset lingually). The mctaconid and protoconid lie opposite each other, as do the smaller entoconid and hypoconid. A trigonid basin is present, but very small. The hypoconulid region is large. Hie hypocristid is short and runs around the back ot the tooth; on the L, it bears a small cuspid in the midline. The cusps do not extend across the midline of the tooth. M3 hypoconulids are sli^'itly mo-.i buauliy placed than in M 1 - M 2 .

296

SITE

REFERENCES Isaac, G. L. 19t>7. The stratigraphy of the Peninj G r o u p — early Middle Pleistocene Formations west of Lake Natron, Tar.ra.nia. In: \Y. Bishop and J. D. Clark (cds.), BjikfrziirJ /s EzKJstTiort in .Jrri+J. Chicago: University ot Chicago Press, ^ 2 2 9 - 2 5 7 . Isaac, G. L. and G. H. Curtis, 1974. Apr of early Acheulian industries, from the Peninj Group, Tanzania. Xjfure 249: 624-627.

ENTRIES

Thouvcny, X . and M . Tiicb. 19S7. Etude pAlconugnctiqu des formations du Plio-Pleistocenc de la region <JC l Peninj (oucst du Lac Natron, Tmzanic). Liniitcs A 11 interpretation magnetos tratigraphiquc. Sci Gcol. Bull. 4057-70.

Repository National Museums of Kenya, P O Box 4065$, Nairobi Kenva (clearance to view needed from Tanzania Department of Antiquities, Dar cs Salaam).

Leake), L. S. B. and M . D. Leakey. 1964. Recent discoveries o: fossil hominids in Tanganyika: at Olduvai and near Lake Natron. Xiivre 202; 5 - 7 .

P E N I N J F i g u r e 1. N M T \ V N 64 120, incomplete mandible (scales = 1 cm).

297

PENINJ (LAKE NATRON)

i

^^w«. Sfi&M

J

y

I SO.

f *;

MFT^

1

•rtsw

«

^3

W m

r

1 ^M

1

PENINJ

Figure 1.

(Continued).

1

STERKFONTEIN

Precambrian dolomites. The site, discovered by lime miners, was extensively modified and emptied by blasting in the decades before W W II, and reconstruction of the complex history of its infilling required extensive work by Brain (1957,1958) and later investigators (notably Partridge, 1978 and Clarke, 1994). Six members have been recognized in the Sterkfontein Formation, numbered 1 to 6 upward (Member 6 being very substantially younger than Member 5). Members 2 - 4 were determined to show normal magnetic polarity, reckoned to represent the Gauss Chron (Jones et al., 1986) and thus to be older than 2.58 M a (but see more detailed paleomagnetic information for Member 2 in Partridge et al., 1999, 2003). Faunal comparisons suggest an age for Member 4 (broadly equivalent to the "Type Site" in earlier terminologv) of about 2 . 8 - 2 . 6 Ma (see Partridge, 1982; Vrba, 1982; Kuman and Clarke, 2000). Schwarcz, Griin and Tobias (1994) reported an average ESR date on bovid tooth enamel from Member 4 in the vicinity of 2.1 Ma, but with a rather large estimated error. Member 5 (broadly, the "Extension Site ) is less well dated faunally; Vrba (1985) has noted that the deposits conventionallv assigned to this member might contain mixed faunas from several time periods, as the work of Kuman and Clarke (2000) also suggests. An estimated range of between 2.0 and 1-5 Ma is, however, reasonable (Partridge, 1982; Vrba, 1982, 19S5), and an age o f this order for Member :> fits comfortably with the faunal scriation of Mckee, Thackeray and Berger (1995). Flowstone polarities in

LOCATION Infilled solution canty in dolomitic limestones, ca. 10 km N\V of Krugersdorp, Gauteng, South Africa (Map 4). DISCOVERY R. Broom and lime miners, August 1936. Brooms researches continued through 1939, and were resumed in collaboration with J. T. Robinson from 1947 to 1949. Between 1956 and 1958 further excavations were carried out by C. K. Brain and J. T. Robinson. Work was recommenced in 1966 bv A. R. Hushes under the direction of R V. Tobias, and has continued to the present, since 1991 under the supervision of R.

J. Clarke. MATERIAL Since 1939 over 600 hominid fossils, mostly fragmentary, have been recovered from the Sterkfontein breccias. Among the most famous of these fossils are the cranium Sts 5 ("Mrs Pies"), the partial skeleton Sts 14, the lower face/mandible Sts 52a/b, the cranium Sts 71, the cranium StW 53, the partial cranium S t W 252, the partial skeleton StW 431, the partial cranium StW 505, and the recently discovered StW 573 skeleton from Member 2. DATING AND STRATIGRAPHIC CONTEXT The Sterkfontein site consists of calcified rubble and ftWtones filling a complex of solution cavities in

298

STEKKFONTBIN

Member 2 were recently employed to assign an age of \tf Ma to the one hominid skeleton (StW 573) known from this level (Partridge ct ah, 1999), and the latest estimates, using the cosmogenic aluminum-26 J beryllium-10 burial dating methods, make it even older, ca. 4.0 Ma (Partridge et al., 2003). Virtually all Stcrkfontcin fossils that have been assigned to the genus Australopithecus come from Member 4. Most authors today would probably regard jU of these as A. africanusy but Clarke (1989) favors the view that a second species, closer to Paranthropus and best represented by the (very) partial cranium StW 252, is also present. The cranium StW 53, assigned to Homo cf. habilis by Tobias and Hughes (1977), was reported to be from the tool-bearing deposits of Member 5; but Kuman and Clarke (2000) now conclude that this specimen actually derived from an infill, temporally intermediate between Members 4 and 5, that they estimate at ca. 2.6 Ma. Further, these authors note that on morphological grounds StW 53 is better assigned to Australopithecus (see also Clarke, 1995) than to Homo; see Volume 2 of this series for further information on this specimen. A second infill ("the Oldowan infill"), faunally dated to ca. 2.0-1.7 Ma (Cooke, 1994; Kuman, 1994, 1996), contains a handful of fossils assigned to Paranthropus by Kuman (1994) and Kuman and Clarke (2000). Member 5 is more notable for artifacts than for hominid fossils (see below); and according to Kuman and Clarke (2000) few if any of the Member 5 hominids are diagnostic, although these authors note that the crushed mandible StW 80 shows strong similarities with the Telanthropus capensis holotype from Swartkrans. ARCHAEOLOGICAL CONTEXT Robinson and Mason (1957) first reported the occurrence of stone tools in the "Extension Site" at Stcrkfontcin (C. K. Brain having earlier found lithics in adjacent miners' dumps). Numerous additional lithics have since been found both in dumps and in situ in breccias of Member 5 (see account by Kuman, 1994). Oldowan lithics have been found in an infill estimated at about 2.0-1.7 Ma old, along with both Paranthropus and undiagnostic hominid fossils (sec earlier). Two assemblages of Acheulean artifacts strongly resembling East African lithics dated at around 1.5 Ma are present in another infill in Member 5 West (Kuman, 1994; Kuman and Clarke, 2000), as is Homo ergaster if

299

the mandible StW 80 is to be so assigned. The StW 53 infill is devoid of in situ artifacts, as arc the breccias of the Australopithecus-yielding Member 4. No definite association can be made between the lithics and any specific hominid. PREVIOUS DESCRIPTIONS AND ANALYSES In 1936 Robert Broom, never one to shrink from naming a new taxon, created the new species Australopithecus transvaalensis to contain a partial cranium and endocast (TM 1511) of a new adult "large anthropoid" from Stcrkfontcin, which he recognized as being generally similar to the (juvenile) "Taungs ape" that had been described by Dart some years before (Broom, 1936a). Later in the same year Broom (1936b) provided a more detailed account of the dentition of this specimen, in detail "sufficient to show that the Stcrkfontcin ape is not a chimpanzee, and that it approaches man in quite a number of characters" (p. 719). Subsequently, however, Broom became more impressed by the differences he perceived between the Stcrkfontcin and Taung specimens, and transferred the former to the new genus Plesianthropus (Broom, 1937). Broom's monograph on the South African early hominids known up to that point was published in 1946 (Broom and Schcpcrs, 1946). After the pace of work at Stcrkfontcin had picked up in 1947, Broom (1947a) reported the discovery of a tolerably complete if edentulous cranium (Sts 5) and mandibular and postcranial elements (Broom, 1947b). By this time, Broom had come strongly to the view that, "though their brains were small," the Taung/Stcrkfontcin fossils were "more human than anthropoid in structure. The conclusion to which some of us have come, namely, that man has evolved from an Australopithecinc of Pliocene times, seems likely to be proved correct" (Broom, 1947b: 431). Like most authors by then, he used the subfamilial designation in the wake of Gregory and Hcllman (1939), who had (in a somewhat unconventional manner) classified the "South African man-apes" in their own subfamily Australopithccinac. Interestingly, although most subsequent commentators have proceeded as though they had done so, Gregory and Hcllman did not formally place their new subfamily within the family Hominidac.

The year 1947 was a pivotal one for the australopiths, for it was then that Wilfrid Lc Gros Clark

300

SITE

visited South Africa and returned to England to convince his still-sceptical British colleagues that the australopiths were indeed early hominids (see account in Le Gros Clark, 1967). Across the Atlantic, Mayr (1950) then went as far as to lump all the australopiths into Homo transvaalensis, the earliest stage in a lineage leading through Homo erectus to Homo sapiens. Thankfully, few were prepared to follow Mayr to this extreme (though Robinson [e.g., 1972] still favored Homo africanus); but by the early 1950s all Sterkfontein hominids were routinely accepted as members of Australopithecus africanus. Robinson (1954) placed all of the "gracile" australopiths (Taung, Sterkfontein and Makapansgat) in the species Australopithecus africanus, but separated them into the subspecies A. a. africanus (Taung) and A. a. transvaalensis (Sterkfontein and Makapansgat). The subspecific designations have not found favor, but many now follow Robinson (and Broom) in separating the "gracile" and the "robust" (Swartkrans and Kromdraai, now also Drimolen) forms into the genera Australopithecus and ParanthropuSy respectively. Since the 1950s many more hominid fossils have been recovered from Sterkfontein (see, for example, Clarke, 1988 and 1990), and most of those that have been described (as not all have) are assigned to Australopithecus africanus. However, Clarke (1990) has argued that a second morph of Australopithecus, exemplified by the (very) partial cranium StW 252, is also present in Member 4 at Sterkfontein. He favors the idea that this morph represents a distinct species that is more closely related to the "robust" forms than is A. africanus. Additionally, Clarke (1995, see also Kuman and Clarke, 2000) has argued that the StW 53 cranium assigned by Hughes and Tobias (1977) to Homo is close to Member 4 in age and attributable to Australopithecus. More taxonomic revisions are highly likely to come. The recendy discovered skeleton from Member 2 of Sterkfontein has yet to be more than partially extracted from its matrix, but has been characterized by Clarke (1998, 1999) as an Australopithecus. Partridge et al. (1999) go farther, considering it to belong to "a species of Australopithecus other than africanus" (p. 293). Holloway (2000) cites the following endocranial capacities for Sterkfontein crania: Sts 5, 485 ml- Sts 19/58,436 ml; Sts 60,428 ml; Sts 71,428 ml. Conroy et al. (1998) quoted a CT-derived estimate for StW 505 of 515 ml. In the same paper Conroy et al. gave a similarly derived estimate of "probably closer to

ENTIUES

370 cm3" for Sts 71, but later revised this estimate t0 match Holloway s (Conroy et al., 2000).

MORPHOLOGY Please see Volume 2 of this series for morphological information on Sterkfontein specimens that have been allocated to the genus Homo. The StW 573 skeleton from Member 2 is still under excavation and is not considered here. The Sterkfontein material presents such a wideranging array of morphologies that it is difficult at times to be certain whether one is dealing with a number of distinct morphs or only with parts of morphs. As at other sites, difficulties in analysis arise from the ever-present problems of combining upper and lower dentitions into a single morph, associating edentulous crania with dental morphs, and of recognizing when tooth wear has altered original details of dental morphology. After much consideration and comparison across sites of various possible morphs, and especially until detailed studies have been done on the effects of wear on tooth morphology (and not just on the occlusal surfaces but on the sides of the teeth), we believe that one practical starting point is to suggest that at least one large and variable upper dental morph is present at Sterkfontein: one bearing similarities to the Taung specimen. Within this larger grouping of specimens other morphs may be delineated if desired, principally on the basis of the degree of development of upper molar cingula. If it is considered desirable to subdivide, a more refined Taung morph could be based on possession of the least amount of upper molar (unguium, and would include Sts 2, 8,17,24a (in part), 32, 42, and 52a and StW 183a and 252. Specimens with more developed upper molar cingula that might constitute a reasonably unitary morph are Sts 1, 22, 35 (possibly) and StW 73 and 498. A third submorph, which includes Sts 12, 24a, 28 and 37, can be distinguished by an even greater expression of upper molar cingula; these specimens also differ from others in that their protocristae, especially the postprotoenstae, are not as pronounced. Of these three possible submorphs the last is the most distinctive, while we are rather reluctant to distinguish formally between the first two because of problems raised by molar wear. Thus it is possible that some teeth (e.g., StW 183a), which could be allocated to the Taung (un-to-poorly cingulated) upper dental submorph because their

O T 13 U K F O N T IS I N

iolar protoconcs bear only a couple of small pits on their lingual surfaces, had in fact originally borne more extensive lingual cingular elaboration. Below, we informally group the descriptions of the specimens we allocate to the Taung upper dental morph on the basis of their apparent upper molar cingulum development. With regard to the Taung upper and lower dental morphs, although only the M i s of the Taung specimen had erupted to complement the deciduous teeth, the occlusal morphology of these permanent teeth has the advantage of being unaltered by wear. Thus the Taung submorphs can include specimens that possess a mixed dentition as well as those with permanent dentitions alone. The most gratifying aspect of the Taung upper and lower dental morphs is that, if the allocation of specimens to each is ultimately corroborated, these dentitions can be regarded as representing the same taxon because of their association in the Taung specimen. Specifically, the lower dentitions of Sts 52b and S t W 498c, although generally quite worn, do display clearly on their M 3 s the distinctive "criss-crossed" pattern found on the M i of the Taung specimen, in which the very lingually distended protoconid obliquely truncates the metaconid d/1. Since it appears reasonable to accept the association of the Sts 52b mandible with the upper dentition and face of Sts 52a, as well as the association of S t W 498c with the upper dentition of S t W 498a, and since both of these upper dentitions can also be included with confidence in the larger Taung morph (see later), we possess additional information about the "adult" Taung individual, not only in terms of the complete permanent dentition but also with regard to aspects of cranial (and especially facial) morphology.

Taung Upper Dental Morph: Specimens with Little or No Upper Molar Cingulum Development [includes Sts 2,8,17,24a (in part), 32,42, and 52a and StW 183a, 252 and 498], thus also belonging to the Taung facial morph (includes Sts 17 and 52a and StW 183a) Sts 2. L maxillary fragment with broken d m l and dm2, and a portion of R maxilla with broken d m l and part of dm2. On the dm Is the metacone is slightly smaller than the paracone. Appresscd to the latter cusp is a very large, almost shelflike parastyle, to the former, a less enlarged metastylc. As seen on the Rdml, the parastyle is the terminus of a relatively short preprotocrista that emerges from the large and

301

internally placed protocone. The metastylc is the terminus of a thick, moderately long postcingulum that emerges from a somewhat m/d compressed and modestly buccally extended hypoconc and encloses a b/1 wide and distinct talon basin. The thick postprotocrista runs to the midline of the base of the metacone. There is a fairly broad notch between the hypoconc and protocone. The Ldm2 is somewhat worn. Its paracone and slightly larger metacone arc peripherally placed and somewhat separated. There is a thick and b/1 long cingulum mcsially on the large and internally placed protocone, which is separated from the much smaller and less lingually extensive hypoconc by a large and deep notch that continues between the cusps as a groove; at the terminus of this groove there appears to be a small prchypoconc crest. A moderate preprotocrista courses mesially around the paracone and a moderate postprotocrista courses up the midline of the base of the metacone. The moderately large hypoconc is somewhat compressed m/d with some buccal extension. A quite thick postcingulum emerges from the distal side of the hypocone and arcs to the side of the metacone. Sts 8. Fragment of L maxilla with M l and M2, M 3 in crypt. M l quite worn, markedly smaller than M 2 , b/1 and m/d. Although the protocristac regions are very worn and there is a hint of mesial protocone cingulum, this M l is remarkably similar to the M l of Sts 12. The M 2 of Sts 8 is also more worn than the partial M 2 of Sts 12, but again in comparable morphologies the two are very similar, including the persistence in Sts 8 of a metaconule-like structure and a distinct and apparendy extensive protocone cingulum. The metacone of the M2 of Sts 8 is also angled or truncated d/1, and this curvature is continued onto the thick postcingulum which, along with the hypocone, swells the crown out distally. The hypocone is m/d compressed and extends buccally to the base of the metaconc. This M2 is also much larger than the M l b/1 and even more so d/1. What can be seen of the M 3 shows that its surface is quite crcnulatcd, and that it is distended in the hypocone region. Sts 8 looks like a large Sts 52a. Sts 17. Crushed and reconstructed partial L face with palate and part of temporal fossa area. Contains R P 3 - M 3 , some broken, and L P 1 - M 1 , some broken. All heavily worn. Alveoli for R P 1 - L C . Part of the supraorbital region is preserved on the L. The shallowly concave orbital roof flows out

302

SITE

smoothly and roundedly up the superior orbital margin, which is quite thin s/L There is a slight depression medially behind the superior orbital margin. The temporal line emerges very medially and high up behind the supraorbital margin. There is quite marked postorbital constriction, so that a significant pan of the orbital cone faces on to the temporal fossa. The preserved infraorbital region is flat, anteriorly facing and vertical The moderate, downwardly facing infraorbital foramen lies somewhat below the inferior orbital margin, and distinctly to the side of a rather low, flattened "pillar" that extends up from the small canine root and runs up beside the lateral nasal margin (cf. the squarcd-up snout of Sts 5). The anterior root of the zygomatic arch takes origin above M l , and its straight inferior margin runs very sharply up and out. On the L the inferior corner of the nasal aperture is especially preserved, and is smoothly rounded. T h e nasoalvcolar clivus is only moderately long. It angles somewhat forward and is quite flat across. T h e inferior nasal margin is marked by a small midline swelling, immediately behind which lie the small incisive fossae. There is a slight stepping-down into the nasal cavity, but no distinct inferior margin. The aperture was moderately broad inferiorly, and probably not very tall The palate was moderately long and broad, and is somewhat rounded across the front. It sloped gently back behind the incisors and would have been quite deep posteriorly, probably with relatively sloping walls. The moderately sized incisive foramen lies level with P2 and is oriented forward. It continues forward as a shallow groove to between the l i s . The II alveoli arc of moderate size but are larger than the I2s. The roots of both would not have been very long, and the crowns were probably not very large. C alveoli arc a bit larger than those of the l i s , and slightly obliquely oriented. The roots and crowns were apparently not very big. The P I crown is short m/d, but not excessively so, and is somewhat parallelsided. It is rounded on its lingual surface, and bears a buccal depression mcsially. There is only one buccal root. P2 was apparently subequal to the PI in b/1 width, but was more swollen distally. There is a mesial and a distal crease on the buccal surface, and a single buccal root. The Ms, although variably preserved, clearly became larger m/d and b/1 from M l to M 3 . The M i s are broken, but were somewhat squarcd-up d/1 by the somewhat m/d compressed hypocone that extends buccally to meet the mctaconc; there was a

ENTRIES

stout postcingulum that terminated at the side of tV cusp. The very worn M 2 preserves a protostvlar p* and a mctaconule in what had probablv been a sto postprotocrista. T h e m/d compressed hypocone extends buccally to contact the somewhat b/d-truncated metacone; a stout postcingulum courses between the distal sides ot these two cusps, and apparentlv enclosed a very small but deep basin. The preserved lingual portion of M 3 bears a strong protostvlar pit mesially, and a lingual cingulum on the protoconc that extends around the mesial side. These teeth are generally similar to those of Stsl, and the conformation of the face is generally reminiscent of Sts 5, especially in the infraorbital plane and the position of the infraorbital foramen relative to the snout. Sts 24a (in part). Unworn crowns of R and Ldmls (suggesting they come from a different individual than the other Sts 24a material, see below). These teeth are dominated by a b/1 compressed, somewhat peripherally placed paracone in the midline of the crown. Mesial to it is a small spikelike protoconc. A thin crest runs between the apices of these two cusps. A crest runs down the mesial edge of the paracone and turns quite sharply lingually to flow into the protoconc. A shorter crest runs down the distal edge of the paracone and corners inward to fade out quickly. Distal to this little crest is a very thick postcingulum that emerges low down on the lingual side of the protocone and thickens as it curves around the distal side of the tooth to terminate in a blunt style. In outline, these d m l s are triangular. Sts 32. Fragment of L maxilla with probable M2, very worn. Visible is a very large and internally placed protocone, an m/d compressed hypocone that extends buccally to the base of the metacone, a vestige of cingulum around the protocone mesially, and a short, thick postcingulum. Reminiscent of Sts 1 and 8, but this M 2 is not as distended buccally as the M 2 of the latter. Sts 42. Very worn R P 1 - M 3 in some bone. Crushed, cracked. M 3 crcnulatcd, swollen hypocone; reminiscent of Sts 52a. Sts 52. Sts 52a is a partial lower face with full dentition, M 3 not fully erupted; the specimen is apparently somewhat compressed laterally. Sts 52b is a slightly crushed and distorted mandible that is discussed with the Tilling lower dental morph. T h e nasal bones of Sts 52a arc long and thin, probably with a central keel and flaring somewhat

S T E It K V O N T E 1 N

• jfcriorlv- The frontal processes are narrow and forrdlv facing. The intcrorbital region was probably fairlv "flat originally, and not very broad. The relatively flat preserved R infraorbital plane faces forward, up and slightly laterally. The zygoma bulges forward slightly at its lateral extremity. The anterior root of the zygomatic arch arises well above the region of P2-M1, and runs steeply upward and out. It then curves sharply backward. The preserved lateral margin of the nasal aperture is relatively sharp; inferiorly a steep stepping-down into the floor of the nasal cavity creates a distinct though rounded inferior nasal margin from which the moderately long and rather narrow clivus descends steeply to the alveolar margin. The nasal aperture itself appears to have been moderately tall but not very wide at its base, and tapers only modestly upward. Bilaterally, quite gracilc "pillars" rise from the canine roots, but fade out lateral to the inferior nasal margin. Lateral to these pillars, or more correctly behind them, is a deep fossa that throws them into relief. On the R there are two, and on the L three, small infraorbital foramina that lay well below the inferior orbital margins. The palate is moderately long, and originally was probably moderately wide. It is deep, with rather vertical sides and a fairly steeply sloping front. A pair of incisive grooves run from the level of P2 to the C. On the L an incisive fossa is partially preserved in the floor of the nasal cavity. Most teeth are relatively unworn, but slightly cracked. The anterior teeth are large and tall-crowned. The Is are moderately heteromorphic, the l i s being broad and spatulate with shallow lingual surfaces, and the I2s are more symmetrical and slightly shoveled. The Cs are not notably thick b/1; lingually they bear a fairly large mesial margocrista and a small distal one that terminates in a small style. The distal edge is significantly longer than the mesial. P I is slightly smaller, especially b/1, than the P2, but in both the protocones are larger than the peripheral paracones; both cusps are located mesial to the midline of the tooth, and lie peripherally. O n both Ps, the lingual side is longer m/d and more rounded than the buccal, which bears small styles on either side of the paracone that appear to be the termini of mesial and distal crests, and the styles continue as low pillars down the buccal side. M l is slightly smaller in all dimensions than M2, and M 3 is smaller again, especially m/d. the mctacones decrease in size from M l to M 3 (thereby arcuately truncating that region of the crown), while the m/d compressed hypocones, in

303

conjunction with the thick postcingulum, increasingly distend the teeth distally; in all, the hypocone extends buccally to contact the base of the metaconc. Both M2s possess a metaconulc-likc structure. The M 3 crown is somewhat wrinkled, and there arc significant traces of wrinkling on M 2 . M l was probably wrinkled, as well. M3s have a cingulum around the protoconc, whereas the M2s have a slight pit. StW 183. L maxilla and lower face, plus various isolated teeth, cf. StW 252, and showing approximately the same stage of dental development as StW 252, i.e., the M 3 crown is formed but its roots arc incomplete. StW 183a. L maxilla and lower face, including part of zygoma and inferior orbital margin. Has PI and M 1 - M 2 , alveoli for P2 and damaged alveoli for C and I I . Inferolatcral corner of the nasal aperture is smoothly curved medially, and smoothly rounded from inside to out. Laterally there is a trace of the lateral crest; this is rugose and suggests that the crest higher up was sharp. The midline is present, showing the anterior nasal spine lying in front of the inferior margin; to its side the floor of the nasal cavity flows smoothly out on to the moderately long, shallowly concave nasoalveolar clivus (cf. T M 1517a), with a gentle downward curve to the incisive fossa. The inferior nasal margin was not very broad. Medially there is a low, blunt and inferiorly positioned conchal crest that comes quite far forward. The incisive fossa is small and lies far behind the nasal spine. The incisive canal was long, narrow and quite obliquely oriented due to the extensive overlap posteriorly of the apparently lozenge-shaped nasoalveolar clivus and the anteriorly not very thick palate. The incisive foramen was no further posterior than the level of P I . The only evidence of a facial pillar lies below the level of the floor of the nasal cavity; it is distinguished laterally only by a shallow sulcus that extends down from the moderate and downwardly directed infraorbital foramen. This foramen lies not worry far from the inferior orbital margin (again, cf.TM 1517a). The anterior surface of this pillar is flat all the way up, and there is no medial margin to it (because there is no concavity in the clivus—it is not "hammocked"). In side view, the area medial to the pillar is more forwardly positioned, and it appears that the lower part would have projected a bit more anteriorly. Also in side view, the anterior root of the zygomatic arch is flat and forwardly facing, and was probably relatively

304

SITE

vertical. The surface above and medial to the infraorbital foramen is essentially flat.The infraorbital plane is quite flat, and it is vertical when seen from the side. However, it is not extremely deep s/i, and the anterior root of the zygomatic arch takes origin not far above M l . The anterior root of the zygoma emerges close to the sulcus below the infraorbital foramen (cf. Sts 52a). Viewed from the front, the inferior margin of the anterior root curves outward quite strongly. The infraorbital nerve descended to the foramen close to the inferior orbital margin. T h e maxillary sinus was large, but did not extend into the frontal process or into the zygoma. The palate is moderately shallow, and docs not deepen posteriorly. Its side walls arc short but quite vertical. Judging from its partial alveolus the C root was not long or very stout, lying below the inferior margin of the nasal aperture. PI is two-rooted, as was P2. P I was narrower b/1 than P2, which may even have been wider b/1 than M l . P I is quite bulbous lingually, and the somewhat inwardly placed protocone and taller paraconc lie opposite one another, centrally on the crown. In buccal profile the mesial and distal edges are of subequal length, and slope gently. There is a shallow fovea on the buccal side mesially as well as distally, and a distinct vertical crease in the hypocone region. There is a U-shaped, horizontally oriented sulcus between the protocone and paracone, and there is also some wrinkling of the internal surfaces of these cusps. A small buccal pillar lies on either side of the paracone. The somewhat worn M 2 is much larger m/d, and especially b/1, than the more worn M l . T h e two Ms arc similar in that the buccal cusps are less bulbous than the lingual cusps, the hypocone swells the tooth distally but not lingually as well and there is some enamel wrinkling. Also on both, the metacone (which is not arcuately truncated) is subequal in size to the paraconc, the hypocone extends buccally to contact the base of the metacone and the short, thick postcingulum emerges high up from the hypocone to course to the distal side of the metacone. There is a long lingual slope, especially visible on the M 2 , and one or two small pits on the lingual side of the protocone. Also as seen on M2, the prcprotocrista courses around the mesial side of the paracone, while the weaker postprotocrista courses up the internal face of the metacone (this was probably also the case on M l ) .

StW J83 (245). RI1, associated with RI2 (126), and also associated with maxillary fragment Stw 183b,

ENTRIES

with RC 1 . The Is are markedly heteromorphic Th very tall 11 is narrowly spatulate and shallow lintm 11° with vertical grooves. The much smaller 12 is sfi»h T more shoveled, and is roundedly flared laterallv B *u are tall-crowned but short-rooted. The C is ]\ crowned, thick at its base and somewhat curv H buccally, with a well-marked lingual pillar th separates a small anterior fovea from a larger posteri fovea and a low distal and a more developed mesial margocrista. In buccal view the steep distal edge of the C is much longer than the slightly more sloping mesial edge. The root is not very long. This tooth is a good antimerc for S t W 127, an upper LC, with a broken root. There is also a LI2 (169: see earlier) with a broken crown; it is similar in preserved parts to the more complete RI2. One other fragment is uninformative. StW 252. Cranium in small fragments. Not all fragments may be associated (see other sections). StW 252a. Fragment of L maxilla, partly reconstructed, with I I - P I . Steeply curved inferolateral corner to the nasal aperture; the bone curves in smoothly with no lateral crest; the nasoalveolar clivus was long and probably flat across; the clivus flows smoothly into the nasal cavity and down to the incisive fossa. T h e palate is very shallow anteriorly, with a long incisive canal continuing to the base of the I I as a groove (probably double). The incisive fossa lies moderately within the nasal cavity, with some stepping down to it. T h e premaxillary suture is visible, running to the space between the two L incisors. T h e face was probably quite vertical and shallowly dished, as indicated by the bone adjacent to the nasal aperture. T h e teeth are large, minimally worn, except for I I . T h e Is are very heteromorphic, the II being very large and spatulate, and shallowly concave lingually with some vertical grooving. The much smaller 12 is somewhat shoveled, with a more truncated and curvTO

ing lateral flare. For its size, each I has a long root, ihas a distinct distal margocrista and a basal swellingThe large crown of the long and stout-rooted C has long and steep mesial and distal edges, and is slightly swollen and shallowly grooved buccally. There is a mesially placed lingual pillar with a small heel below, from which emanate thick mesial and distal margocristae that terminate in small stylclike structures at the termini of the mesial and distal occlusal edges. On each side of the pillar there is a shallow fovea. PI has

S T E KKFO N T E I N

305

three distinct roots; its crown is slightly exodaenodont buccally and is somewhat m/d longer on the more tightly curved buccal than on the more broadly curved lingual side. The slightly b/1 compressed paracone is hitrlv centrally and somewhat internally placed, and bluntlv crestlikc mesial and distal edges slope gently aw.iv from its apex. The lower and more bulbous protocone is also internally placed, if mesially shifted. The anterior fovea is slightly larger than the posterior. In buccal view the mesial edge is longer and steeper than the distal one.

StW 252h. RM3 with undeveloped roots. It has internally placed buccal and lingual cusps with long sloping sides; the metacone region is obliquely truncated, with a short, beaded postcingulum apprcssed distally to the small metacone. There is a large metaconule, a distally distended hypocone, a protostylar shelf and a thick preprotocrista runs around the metacone. There is a continuous cresting system linking the metacone with the hypocone. This is a trapezoidal tooth that tapers distally, and is comparable to StW 2521.

StW 252b. Palatal fragment lacking teeth. Not necessarily matched with the preceding. Very long incisive canal. The palate would have been narrow, parallel-sided with steepish walls. May not go with this specimen (or perhaps morph?).

StW 2521 RP2 with three closed roots. StW 252i-l appear to be associated.

StW 252c. Small fragment of R maxilla with C-P2. The C and P I are comparable in size, morphology and wear to StW 252a. P2 is larger, especially b/1, than P I , and also differs in being more broadly swollen distally and more broadly but still somewhat tiehtlv curved lingually, with creasing of the horizontal groove between the large, extremely bulbous, and quite internally placed protocone and the slightly internally placed, puffy but apically b/1 compressed paracone. In buccal profile the mesial and distal edges are subequal in the P2 (the mesial edge is longer in the PI). There is also a fossa on the maxilla between the roots of P I and P2. Comparable to StW 252i. StW 252d. RI2, comparable in size, morphology and wear to the LI2 of S t W 252a. StW 252e. Part of an upper I crown, with a thick lingual swelling. Plausible counterpart to I I of StW 252a, but more worn. StW 252f. Two thick-enameled molar fragments of a small R M 1 , somewhat worn. Large hypocone, very short postcingulum. Plausibly part of this morph. StW 252g. Broken RM2. Minimally worn with very internally placed buccal and lingual cusps, hence the crown has long, sloping sides with a moderate metaconule, a large and d/1 bulbous hypocone, and a very short postcingulum. The preprotocrista runs around the mesial side of the protocone. The metacone region is rounded and slightly truncated. There is a crease on the lingual side of the protocone. Comparable to StW 252k.

StW 252}. Fairly worn L M l , matched by the StW 252f fragment. Buccal and lingual sides are somewhat sloping, but with the large and somewhat mesially placed protocone is more internally shifted than the buccal cusps. The paracone is slightly smaller m/d than the lingually truncated metacone. The moderately distally swollen hypocone, which makes a fairly long contact on the internal extent of the metacone, is long m/d but not very extensive b/1. A short postcingulum (or is it the remains of a metaconule in a worn-down postcingulum?) is nestled between the metacone and hypocone. This subtrapezoidally shaped tooth is much m/d longer buccally than lingually. There may have been a faint trace of cingulum on the lingual face of the protocone. StW 252k. LM2 with very internally placed buccal and lingual cusps and strongly sloping sides, especially lingually. This only moderately worn tooth is much larger in all dimensions than StW 252j and is morphologically similar to it in many details, thereby verifying that there is only a very small conulelike structure intruding between the metacone and the very distally and arcuately distended hypocone. There is also stronger evidence than on the M l that there was a very stout postprotocrista that ran from the verv large and internally placed protocone to at least the base (if not up the internal face) of the very lingually truncated metacone. The apparently very short preprotocrista courses tightly around the mesial side of the paracone and roundedly swells the parastylar region a bit. There are mesial and distal crease's in the protostylar region (suggesting perhaps the presence originally of some cingulum), as well as a vertical, lingual pillar-like structure in the region between the protocone and hypocone.

306

SITE

StW 2521 RM3 crown, roots not developed. This distally tapering tooth is longer m/d than the M2 but about as wide b/1 only mcsially. There is much more thick crenulation than on the other two upper Ms, which suggests they were similarly grooved originally. As in the M2, the buccal and lingual cusps are somewhat internally placed and their sides somewhat sloping and bulbous. The metacone is quite small and what may be the postprotocrista arcs mcsially to the region where the paracone and metacone bases abut one another. The slightly grooved preprotocrista is very thick and swings mcsially around to terminate well internal to the m/b "corner" of the tooth. T h e slightly reduced hypoconc is less lingually expansive than the protocone, and its distal arc is continued by the very thick and conulated postcingulum that terminate at the side of the metacone. There is a thinner vertical pillar of enamel lingually between the bases of the protocone and hypocone. There are also vertical shallow grooves on the l i n e a l side of the protocone as well as a small patch of low cingulum. This tooth is comparable to StW 252h, but the protostyles are less fully delineated, and there is more wrinkling, especially around metacone. StW 2S3. L M 1 - M 2 in a small piece of maxilla. The very worn M l shows evidence of a large protocone, a paracone that is larger than the slightly buccally truncated metacone, an m/d compressed hypocone that extends lingually to the base of the metacone and a very short, thick postcingulum that terminates on the distal side of the metacone. Wear has greatly enlarged the trigon basin. The less worn M 2 , which is noticeably larger b/1 and especially m/d, has a very large and internally placed protocone with a protostyle and above it a protostylar pit; a series of thin vertical grooves separate it from the distally expanded and rounded hypocone. A moderate preprotocrista swings far out mesially before turning in to the paracone. A much weaker postprotocrista runs up the internal face of the arcuatcly truncated metacone, which is smaller than the paracone. The hypocone extends far buccally to meet the base of the metacone, and a very short, curved postcingulum bearing a large conulc connects it to the metacone. Some enamel wrinkling is visible (was probably more significant before wear). StW 49H. Consists of various fragments, crushed and/or broken, of upper and lower jaws attributed to the same individual, which appears to be justified on

ENTRIES

the basis of occlusal compatibility, comparabl amounts of wear on P l s - M 3 s (especially the much less worn M3s), coloration and the way in which the M3s arc similar in their expression of cuspulation and crenulation. StW 498a. A partial L maxilla to the midline with very worn and variably cracked 1 1 - M 2 in situ, and a much less worn M 3 associated. All teeth are very worn, some cracked; the improperly erupted RC overlies the 12 and P I buccally. The palate is long, and the tooth rows arc markedly divergent posteriorly (cf. lower jaw and apes). The jaw is of moderate size with a strong pillar continuing from the large canine root alongside the preserved lower portion of the nasal aperture, which is flat anterolatcrally. The margin of the nasal aperture is rounded and its inferolateral corner also arcs medially without a break. The floor of the nasal cavity flows smoothly out and down, onto the downwardly gently curving nasoalvcolar clivus, which is also curved from the midline to the C. The low, longitudinally crestlike anterior nasal spine lies well back on the floor of the nasal cavity and behind it is the apparently small left incisive fossa, which appears to be angled forward sharply. There is very little stepping down from the posterior pole of the nasoalveolar clivus to the incisive fossa. The preserved lower lateral portion of the L margin of the nasal aperture is tilted slightly medially, suggesting that the top of the aperture would not have been excessively narrower than the inferior margin. Lateral to and actually also behind the pillar, and broadly level with the inferolateral corner of the aperture, there is a very deep canine fossa above the root of P I . Along its whole length, the pillars posterior margin is sharply cornered down into the fossa, thus giving a flattened rather than rounded external surface to the pillar. The fossa accentuates the snoutlike character of this lower face which, as judged from the nasal margin, was probably not excessively dished. Farther back there is no trace of the anterior root of the zygomatic arch, suggesting that its origin was high above the alveolar margin. W h e n the M 3 is included, the maxillary sinus appears to have extended that far back along the jaw. T h e palate is quite shallow anteriorly and deepens only slightly posteriorly, with sloping walls. The apparently single small incisive foramen lies opposite P2 and continues forward as a shallow groove. 1 here is a possible abscess around the lingual roots or M l . and maybe also M 2 .

S TKIt KKONTK1N

With regard to teeth, there is noticeable incisor hcteromorphy, the II being much larger overall and more broadly spatulate. Both Is, however, appear to have been more distended mcsially with slight flare distallv. The C is large with a long root; the distal slope is longer than the shorter, more vertical mesial eitee; the crown curves buccally toward the neck, and has a thin lingual pillar with a moderate mesial and longer distal fovea beside it. The Ps are almost subequ.il in size, P I being slightly smaller b/1, and are similar in shape, with round lingual surfaces, mcsially placed protocones, thick short postcingula and shallow mesial and distal grooves on the buccal surface that delineate faint stylelike structures. PI is slightly more truncated distolingually than P2. T h e Ps arc not very narrow m/d, and thus appear somewhat chunky relative to the Ms. However, they are not extremely large relative to the size of M l . M l would have been squarish and shorter m/1 than M 2 . M 3 is subsquare and somewhat smaller than M 2 . It appears that the metacone region becomes more obliquely truncated posteriorly, and the metacone itself smaller, with a concomitant increase in the size of a metastyle-like structure on its distal side that is the terminus of a thick postcingulum. T h e M 3 has a large mctaconule and protocone, as had the M 2 , as well as fairly complete lingual cingulum and some wrinkling on its sides. The subtriangular-shaped hypocone is relatively long m/d, and its peak contacts the metaconule. T h e thick postcingulum is creased in places, producing the "metastyle* on the side of the metacone. T h e postcingulum of M 2 (which is very reminiscent of the M 2 of TM1517a) was apparently similar. StW 498b. A crushed lower face and jaw, primarily from the R side. T h e right nasal margin is sharply rounded, and laterally there is an apparent canine fossa and edge along it as seen in S t W 498a. T h e anterior surface of the region of the pillar is flat rather than rounded. T h e medial part of the inferior orbital plane is flat. A little bit of upper nasal aperture margin is preserved, and shows a smoothly rounded lateral crest. The bone above is flat. T h e pillar continues all the way up the nasal margin. The preserved RI1 and R C - M 3 arc worn and broken. T h e I I , C and Ps, although slightly more worn, arc similar in size and shape to those teeth in StW 498a. T h e M 3 is largely intact, and is comparable to that in 498a, though it is somewhat larger especially b/1, and has more occlusal wrinkling. T h e

307

metacone-metastyle relationship on M 2 is as in StW 498a. StW 49Sf. Scries of small cranial fragments, including part of a R petrosal (498p) with deep subsubarcuate fossa, and a small part of a gracile zygoma perhaps indicating a squarish orbit (cf. T M 1517a). Also, a fragment of R parietal, near the parietomastoid suture, that shows a lateral flanging of the lower part of the parietal. Moderate Upper Molar Cingulum Development [includes Sts 22,35 (possibly) and StW 73] Sts 22. Broken R M 1 and adjacent M 2 crown, both very worn and without roots; these have been suggested by Clarke (1990) to go with S t W 73. M l is essentially uninformative, except for the preserved and very rounded metacone region. The M 2 is very similar to the M 2 of Sts 12. Sts 35. Very worn and crushed upper L P 1 - M 2 in matrix. Premolars appear to have been somewhat ovoid in shape (cf. Sts 12). StW 73. Part palate with L P 1 - L P 2 , lingual halves of RP1 and M 1 - M 2 ; alveoli for anterior teeth. This small palate is long and fairly narrow, with parallel sides, and is gently arced across the front. It slopes strongly posteriorly from behind the anterior teeth; its sides are almost vertical. It has been prepared so as to make it appear that there arc two incisive foramina. There is a strong stepping down from the relatively long and forwardly angled nasoalveolar clivus to the apparently large, forwardly placed incisive fossae. T h e nasal cavity itself is very narrow, especially in the midregion where the maxillary sinus walls swell somewhat medially. T h e nasoalveolar clivus has a slight downward arc toward the alveolar margin, and is faintly concave from side to side ("hammocking"). T h e transition from the nasal cavity to the nasoalveolar clivus is smooth, and the inferior boundary of the narrow nasal aperture is smoothly curved from side to side, with rounded infcrolatcral comers. There arc no facial pillars per sc, but the region from the lateral aspect of the nasoalveolar d i m s around to the side of the maxilla is broadly and smoothly rounded, forming "corners" to the jaw. On the L is preserved a shallow depression between the roots of the Ps. The maxillary sinus docs not extend anteriorly farther than the P2. T h e l i s arc much larger than the 12s, whose roots have been quite compressed. The C alveoli are

V 308

SITE

relatively small. It appears that none of the anterior tooth roots would have been long. PI is only slightly smaller overall than P2, and its buccal side is longer than the lingual one m/d, whereas the reverse applies on V2. PI and P2 arc rather chunky looking teeth, wide b/1 relative to their length, and both appear large relative to the fairly small M l (cf. Sts 12). Both Ps bear mesial and distal buccal pillars, the mesial being the larger on PI and the opposite being the case on P2. On PI the paracolic is somewhat distally shifted, and the more bulbous protocone is rather centrally placed. On P2 the paracolic is central, and the subcqual protocone is mesially shifted. On PI the preprotocrista is larger than the postprotocrista; the reverse applies on P2. On PI the protocone is slightly more internally placed than on P2. P2 shows some minor wrinkling in the horizontal groove between the two cusps. The enamel on M 1 - M 2 was somewhat wrinkled. On M l there arc two deep horizontal grooves on the lingual face of the protocone, while on M 2 there is a fairly complete lingual cingulum. On both teeth the protocone is very large and the hypocone appears moderately long m/d, and on M l it extends buccally to contact the metacone. The postcingulum on M l is very short. Marked Upper Molar Cingulum Development (includes Sts 12,24a, 28,37) Sts 12. Crushed maxilla with L P 1 - M 2 , cracked, and part of R P l (?) and crushed R M 1 - M 2 . All teeth very worn. The Ps are rather bulk}' looking, in part due to their m/d length versus b/1 width, which gives the impression that PI and especially P2 were large relative to the M l . PI is slightly smaller than P2; both are wider b/1 than long m/d. Both are also quite rounded on the lingual side, with the mesially shifted paracones being much larger and taller than the even more mesially situated protocones. M l is quite broken, but it was probably roundedly square and noticeably smaller m/d and b/1 than the M 2 . Even with wear, there is evidence on M l of cingulum around much or all of the very large and probably somewhat internally placed protocone. The large, roundedly square M2 is broken and worn, but preserves a lingual cingulum around the entire base of a very large, internally placed protocone that probably drastically restricted the trigon basin. The paracone and very slightly d/b-truncated metacone are subequal in size and are somewhat peripherally placed. T h e

ENTRIES

I

small and apparently m/d compressed hv }?°conc more or less opposite the metacone, and th cr lies thick, possibly beaded postcingulum that SI e is a ^00thly joins the distal side of the metacone. Sts 24a. Includes a R maxilla with the inf • part of the anterior root of the zygomatic a rior \ Alveolus for dc, very worn d m l - d m 2 , and sliehtl* worn M l . Also a tooth crown developing up in th* jaw The L maxillary fragment is largely reconstructed and includes a very worn and damaged dml-dm2 Also various isolated teeth and tooth fragments Th upper teeth are represented by R and LI crowns L broken. RI1 is tall-crowned, slightly flared laterally with fairly convex buccal and concave lingual surfaces The crown is thickest m/d at the base. Lingually there arc a few low pillars at the base. Also present are the crowns of the R and LI2s, considerably smaller than the l i s and slightly flared mesially, more so laterally. These crowns are relatively narrow, convex buccally and concave lingually with distinct margocristae. The crown of a probable R P l (reminiscent of the rounder premolars of Sts 12) has a deeply wrinkled surface; the relatively large paracone is centrally placed; the smaller protocone is more mesially placed. The two cusps are widely separated. The mesial and distal edges of the paracone are gently sloping and subequal in length; there are two grooves on the buccal surface toward the edges. A thin preprotocrista runs straight up the side of the tooth to flow into the edge of the paracone. It encloses a b/1 wide but not very long basin. A postprotocrista runs a bit distally before turning up the distal side of the tooth and flowing into the paracone. It encloses a rather larger basin. There are also two other uninformative dental fragments. In the maxillary fragment, the dml-dm2s are very worn, and partially broken on the L. As seen on the R, d m l is a small, subsquare tooth with a swollen hypocone region. There is some swelling near the neck of the parastylar region, whence descends a thickening of enamel. The buccal side of the paracone region also bears a pillar-like thickening. The subsquare dm2 is noticeably larger than the dml; the metacone is slightly smaller than, but closely ap pressed to, the paracone. A very short, thick posuu gulum emanates from the large hypocone and gcnti> swells out the distal side of the tooth as it runs to tn>. side of the metacone. The minimally worn M " markedly larger than the dm2; its surface is broaf •

S T E K K F OK T E I S

but deeply crcnulatcd. It is longer m/d lingually than buccally. In general this is a roundedly squarish tooth that is distended distally by the postcingulum as it comes off the m/d compressed hypocone. T h e cusps a r c bulbous and confluent at their bases; their apices arc not salient. The large protocone is somewhat intcrnallv placed but docs not constrict the trigon basin. There is some cingulum low down on, and almost completely around, the protocone. T h e protocristac a r c weakly developed and very divergent; the mesial crest courses mcsially and becomes confluent with the prccingulum. A paraconule lies quite mcsially between the paracolic and the protocone. A stout precingulum emerges high on the protocone close to the midline of the tooth, and faces out on the mesial side of the paracolic. The paracolic and metacone are large. T h e postcingulum encloses a very deep talon basin distal to the metacone, and the hypocone extends buccally to contact the metacone. There is also a small prehypocone crista. Sts 28. In the same box with isolated teeth labeled Sts 37 are two other teeth, one of which is clearly labeled Sts 28; this is an RM 2 , quite worn; it appears to have had cingulum around the protocone. T h e thick postcingulum is beaded, and terminates in a style on the distal side of the metacone. T h e buccal side of the tooth curves in from the paracone through the metacone to the postcingulum. T h e other tooth is a broken, heavily crenulated, minimally worn, probable upper M . Sts 37. Crowns of a very worn L M 1 , a less worn LM" and a relatively unworn L M 3 , probably from the same individual. O n all three M s there is extensive cingulum around the protocone, from the mesial side to the hypocone; on M 3 this cingulum is slightly beaded. M l is somewhat smaller than M 2 m/d and b/1, while M 3 is only shorter than the M 2 m/d. T h e protocone region is large on M 1 - M 2 , but it may originally have been buccally truncated, as on the M 3 . The metacone and paracone are subequal on M l , but the former cusp is small on M 2 - M 3 . T h e hypocone region is large on M 1 - M 2 , but on M 3 it is b/d truncated and beaded. A n m / d long, b/1 thick, slightly buccally oriented structure emerges from the distal side of the protocone and lies between the M 3 hypocone and the metacone; it appears a similar structure was present on M 2 and probably also M l . T h e M 3 enamel is somewhat crenulated, and the tooth is more distended distally than the M l . There was cingulum around its protocone. T h e M 2 shape is most like that

309

of Sts 52a. Also an unworn upper LM3 crown, with a deeply and thickly crenulated surface. The metacone is much smaller than the paracone. There is thick cingulum around the protocone, and the region of the postcingulum to the hypocone is quite wrinkled. Taung Lower Dental Morph (includes Sts 52b and S t W 384 and 498c) Sts 52. Sts 52a is a partial lower face with full dentition of the kind already described in the Taung upper dental morph. Sts 52b is a slightly crushed and distorted mandible lacking L ramus, part of R ramus, and part of L corpus; also R I 1 - 1 2 , plus R P 1 - M 3 and L M 2 - M 3 intact; all other teeth are broken. Sts 52b. Smallish mandible. Corpora are not very tall, but are relatively wide m/1. The front of the jaw is rather narrow and strongly curved, with divergent tooth rows behind. In profile the symphysis slopes gently back and down to the inferior border. At the front there is a shallow depression bilaterally below the roots of 11-12, producing a slightly raised area in the midline. Inferiorly there are two tiny and downwardly pointing digastric fossae. O n the R are two or maybe three mental foramina, below P I . T h e anterior root of the ramus took origin below M l , and curved strongly back and up to obscure M 3 . There is a hint of a tall, shallow submandibular notch. T h e coronoid process may have risen above the level of the condyle. T h e sigmoid notch was shallow, moderately long and runs to the lateral side of the condyle. The condyle itself is narrow but quite bulky, with a flat posterior aspect and a flattish profile from behind. Internally there is a short, moderately sloping postincisal plane that is restricted laterally by two well-developed mandibular toral swellings. A t the level of P I the postincisal plane descends vertically to the inferior margin. Midway down there is a small but deep genial pit, below which there is a vertical ridge of bone in the midline. There is no evidence of a mylohyoid line, but on the R there is a well-defined submandibular fossa below P 2 - M 1 . T h e preserved portion of the ramus lacks muscle scars externally, but internally there is at least one small medial pterygoid tubercle above the level of the tooth row. Also at this level, the internal alveolar crest divided into two: a stout crest courses toward the region of the coronoid process, and a shorter crest angles back toward the mandibular condyle. T h e mandibular foramen lies

below this crest.

...tfum National d'Histoire Hatur L*parterr.erit de Pr6histoir€ I.TUoften^Panhard

' 75013 PARIS

MO

SITE

The worn R11-I2 are still fairly tall-crowned. The 12 is more laterally flared than the I I . The C was probably not taller-crowned than the Is. It preserves a central keel on the lingual side, and a distal margocristid that terminates in a small stylid, P 1 - P 2 arc similar in being distended d/1 and in having a small anterior and larger posterior fovea, and PI also bears a mesial pillar buccally. Both Ps possess a distinct, peripherally placed metaconid that lies mesial to the mesially and more internally placed protoconid. The lingual side of PI is obliquely oriented, so the crown tapers mesially. In contrast, the m/1 portion of P2 is squarcd-up. As seen on the R, the Ms are subequal in size; the M l may originally have been longer d/1. On M 2 - M 3 the lingual cusps are somewhat compressed and peripheral, whereas the buccal cusps are internally placed and bulbous. The long talonid basin is therefore constricted b/1. In M 2 - M 3 the hypoconulid lies just buccal to the midline; on M2 a small cuspulid intervenes between the hypoconulid and the entoconid, whereas in M 3 these two cusps are connected by a cristid. On M2 the base of the hypoconid extends across the midline of the tooth; on M 3 and apparently also on M2 there is a cingulid around the base of the protoconid. On M2 there is a small notch on the buccal side of the protoconid, and another between the hypoconid and hypoconulid. On M 3 the enamel is quite wrinkled; traces of wrinkling are still present on M2, which also preserves a small anterior fovea. Better preserved on the M3s, but still visible on the much more worn RM2, is the extension of the base of the protoconid obliquely and in a d/1 direction behind the metaconid to contact the mesial part of the b/1 compressed entoconid (thus making it seem as if the former cusp is truncating the latter). On both M3s, this extension of the protoconid is wrinkled such that it appears as if there is a centroconid lying internally on the metaconid. It is plausible that with wear evidence of this structure would disappear and the tooth would look like LM2, on which the bases of the metaconid and protoconid appear to abut in the midline of the tooth. StW 3S4. Fragment of R mandibular corpus with P 2 - M 3 , very worn. Corpus is not much wider b/1 than the large teeth. Begins to curve in at the region ot P 2 - M 1 . There probably was no mandibular gutter. On the P2 the somewhat internally placed protoconid and the more peripheral metaconid arc mesially situated, with a fairly deep talonid basin persisting

KNTUIKS

distal to the latter cusp, filling out the d/1 corner 0f the tooth, which is slightly distally expanded. Bu cingulid is visible on M 2 - M 3 protoconids. On n\ M 3 a fairly large, b/1 compressed, m / d elongate cuspulid lies between the buccal hypoconulid a A entoconid, and the base of the protoconid continu d/1 behind the metaconid to contact the front of th somewhat b/l compressed entoconid. M3 and even M 2 provide evidence of a very m/d thick paracristid StW 498. Consists of various fragments, crushed and/or broken, of upper and lower jaws (StW 498a and 498c, respectively) attributed to the same individual. This association appears to be justified on the basis of occlusal compatibility, comparable amounts of wear on P l s - M 3 s (especially the much less worn M3s), coloration and the way in which the M3s are similar in expression of cuspulation and crenulation. StW 49Sc. This is part of a L mandibular corpus and ramus with M 1 - M 3 in situ, and P1-P2 plausibly associated. Most teeth are worn. The corpus is quite shallow s/i, and is not very wide m/1. The jaw seems small relative to the size of the molars. The anterior root of the ramus originates below M2 and continues up right next to M 3 , with no development of a gutter. The ramus is broken, but would have obscured M 3 , and it was very long a/p. The thin and rounded gonial region lacks muscle scars externally and internally, and is inwardly inflected. Internally there is a long, thick, low mylohyoid line with a long, shallow submandibular fossa below. The mandibular foramen is large and points up and back, and lies behind the thickened upward continuation of the internal alveolar crest. The latter is broken oft superiorly, but appears to have been fanning out. Coming from the inferior margin of the mandibular foramen is a well-defined mylohyoid groove. P 1 - P 2 are strongly hetcromorphic. They appear chunk)', but arc not excessively large compared to MlP I has a wide and obliquely set anterior root, and is quite bulbous buccally, with the protoconid quite internally and somewhat mesially placed. There is a distinct, wedge-shaped depression on the buccal surface, mesially and toward the neck. Because the lingual side of the tooth is d/1 obliquely oriented the tooth tapers mesially, being b/1 broader distally and distended m the d/1 corner by a thick cristid that comes oft an nvvi compressed metaconid and encircles a lingually shifted and shallow talonid basin. A stout paracri>tid

ONTEIN

mesially and down from the peaked apex of the rotoconid, and turns lingually and back up to the distinct, upwardly peaked, and peripherally placed metaconid. The paracristid encloses a lingually facing, larec and deep basin. The metaconid is connected to the base of the protoconid by a thick crest, of which, eiven the amount of wear, the metaconid appears to be a projecting thickening. The P2 is somewhat loncer m/d and wider b/1 than the P i and is roundcdly square in occlusal outline. The buccal surface is more vertical than in the PI, and there was a metaconid which lay mesial to, and more peripherally than, the apparently somewhat internally placed and very mesially situated apex of the larger protoconid. A thick cristid runs straight back from the metaconid to turn at the distal corner of the crown and course buccallv, thus enclosing an expansive but apparently originally shallow talonid basin. There seems to have been a tiny anterior fovea. M l is much smaller m/d and especially b/1 than M2, which is only slightly smaller than M 3 . The M cusps (particularly the lingual ones) are quite peripheral, especially as seen in M 3 , and the buccal slope is slightly greater than the lingual one. As seen on M 3 , there are two buccal, wedge-shaped depressions. One is on the mesial aspect of the protoconid, and the other on the mesial aspect of the buccally placed hypoconulid; the latter cusp appears also to have been buccal on M 1 - M 2 , which preserve some evidence of the associated wedge-shaped depression. O n M 2 the large, single hypoconulid is wedge-shaped; on M 3 this cusp is subdivided, with two small cuspulids intervening between the larger portion and the entoconid. O n M3 there is a b/1 wide paraconid shelf, and on M 2 a possible trace of such a crest. M 3 is long and ovoid with a rounded posterior edge, and M 2 is shorter but otherwise similar in shape. On M 2 - M 3 the base of the hypoconid crosses the midline and the internal faces of the lingual cusps bear small cuspulids, thus filling in the long and lingually curving talonid basin. Of special note on M 3 is the protoconid, whose base extends d/1 well across the midline of the tooth to contact the somewhat b/1 compressed entoconid (thus giving the impression that the protoconid is truncating the metaconid). s

StW 498d. Crushed R and part of L corpus, with damaged and worn L C - R I 1 and R P 1 - M 3 . The front of the jaw is partially preserved inferiorly and is curved quite acutely across, with probably fairly divergent tooth rows. There is a long, shallow

311

postincisal plane with a deep genial pit and a thickened inferior torus. This is a good match for 498c, but with an eruptive anomaly of the RC. The anterior teeth were narrow and quite tall-crowned. P 1 - P 2 and M3 are comparable to those in 498c, with the M3 in this specimen having a more developed protostylid. Pseudostyloid Group (includes at least an Sts 5 facial and basicranial morph and an Sts 19 basicranial morph) In terms of "snout" morphology, one might consider including StW 183a and StW 498a in an Sts 5 morph. Especially in StW 183a, the blunt "cornering" of the flattened facial pillar, which produces a squared-up shape to the snout, is particularly reminiscent of Sts 5. However, differences in the shapes of the orbit (preserved inferiorly in StW 183a) and the nasal aperture (which in StW 183a curves in much more strongly laterally and is punctuated inferiorly in the midline by a superiorly elevated anterior nasal spine) may argue against this association. We should point out here that a partial cranium from Makapansgat, M L D 37/38, can be grouped with Sts 5 on the basis of also possessing the very unusually configured basiocciput (see below). Sts 19 is sufficiently unlike Sts 5 in some details of basicranial morphology to warrant its being discussed separately (see immediately below), but it should be pointed out that the two are similar in possessing a pseudostyloid process, and, more specifically to them, some pinching of the basiocciput just anterior to the occipital condyle, as well as in aspects of the articular fossa (e.g., m/1 breadth, far laterally placed postglenoid plate). Pseudostyloid processes are also found in some isolated petrosal bones we describe here. Perhaps comparative studies of other details of petrosal morphology will turn up additional information that can be brought to bear on sorting out these morphs. Sts 5. Partial cranium, somewhat reconstructed and lacking teeth, and with somewhat eroded surfaces, at least in places. Moderately thin-boned braincase, somewhat domed, with a smooth profile curve from the frontal to the occipital. The face is long and slightly dished in profile. From behind this is a fairly narrow skull, broadest across the mastoids. Looking down, it does not broaden greatly posteriorly from the rear of the

312

SITE

EX TRIES

temporal fossa. The profile curve of the braincase continues smoothly to the junction of the occipital and nuchal planes."Breakage and loss of bone make it difficult to characterize that junction, but it is undercut slightly by the relatively flat and apparently poorly muscle-scarred nuchal plane. Seen from above, glabella is simply the midpoint of a smooth, shallow curve across the supraorbital region. However, it is steeply undercut below, although this may be exaggerated by an apparent forward rotation of "the lower on the upper face at midorbit. From the front, the supraorbital margins describe very modest curves above the orbits, and glabella is at the lowest point of this sinuous line. There is a slight swelling of the supraorbital margins just lateral to glabella on both sides. The orbital roofs are probably shallowly concave, and flow smoothly out and up into very thin supraorbital margins that taper somewhat laterally, are indented medially by broad, shallow supraorbital notches and protrude forward virtually not at all. Above the supraorbital margins there is almost no posttoral plane, the frontal curving back gently in profile from right behind the orbital margins. Postorbital constriction is quite pronounced, so that a long stretch of the lateral wall of the orbital cone faces on the temporal fossa.

somewhat stepped-down, and there is a distinct an?l between it and the long, flat, forwardly inclined nasoalveolar clivus that is fairly narrow from side to side. Just inside the inferior nasal margin, and down below, lie twinned incisive fossae. There is little preserved morphology on the bone of the braincase, but the central part of the sagittal suture is visible and is moderately denticulated. As seen on the L, the anterior squamous suture flows quite smoothly into the temporal fossa, but there is a moderate demarcation of a small infratemporal fossa below, along the greater wing of the sphenoid. The squamous seems to have been long and possibly low, and the bone of the zygomatic arch is thin s/i as well as m/1. T h e better-preserved and less-deformed R articular fossa is very wide m/1 (lying under the m/1 wide posterior root of the zygomatic arch) and somewhat long a/p and shallow, extending forward with very little indication of an articular tuberosity. The postglenoid plate is quite wide m/1 and very laterally placed, emerging from close to the lateral margin of the auditory meatus and extending well lateral to it, even slightly laterally beyond the articular fossa itself. T h e medial articular tubercle on the R is less well developed and more separated from the petrosal than that on the L.

The orbits were probably roundedly square, separated by a moderately broad interorbital space which is narrowest at midorbit. T h e nasal bones were probably long and moderately thin m/1, though broadest infcriorly, and extended above a break that has often been misidentified as the nasofrontal suture. They were flat across, with no midline keeling. T h e zygomas are flat and forwardly facing and, correcting for the torsion across the orbits, would have been essentially vertical, with no concavity. T h e anterior roots of the zygomatic arches arise above M 2 , and curve only slightly upward and outward, projecting almost directly sideways. The nasal region itself is flat across above, but protrudes slightly beyond the zygomas. Below, the lateral margins of the nasal aperture are thickened into strong pillar-like structures that carry the nasal region forward. They are also accentuated by a fossa lateral to and behind them in which sits a moderately large and downwardly directed infraorbital foramen, lying relatively close to the inferior orbital margin. The pillars extend just below the inferolateral margins of the nasal aperture, but they do not continue down the clivus and are unrelated to the canine roots. The floor of the nasal cavity appears to be

T h e posterior root of the zygomatic arch arises over the anterior part of the meatus, but does not swing far laterally. T h u s there is only a narrow, if long, superior shelf. T h e thin-walled tubular ectotympanic was apparently not fully ossified laterally. The large, ovoid auditory meatus is tilted forward. As seen on the R, the thin base of the broken vaginal process runs from the small, very medially placed and backwardly facing carotid foramen, almost to the edge of the ectotympanic. T h e vaginal process is well separated from the mastoid. Anterior to the carotid foramen is preserved the base of a very thick and anteromcdially oriented pseudostyloid process projecting from the very strongly anteriorly directed petrosal. Just posterior to the carotid foramen lies the tiny, downwardly directed carotid foramen. T h e mastoid regions are damaged on both sides, but the processes probably did not project significantly downward and were only modestly inflated laterally. There is no supramastoid or supramcatal crest. As seen on the R, the mastoid notch is relatively broad, but shallow; breakage obscures the region of the digastric fossa. Medial to the notch, there is a swelling of the bone that straddles the occipitomastoid suture, which

STERKFONTEIN

traverses its high point and runs forward as far as the vaginal process. The swelling may have projected downward slighdy beyond the level of the presumably blunt tip of the mastoid. More laterally, in line with the mastoid notch, lies what appears to be a large stylomastoid foramen. No styloid pit is visible. The base of the vomer lies fairly far forward, and the pterygoid nlatrs are quite close together and parallel for most of their length, though they converge superiorly. The relativc-v large and ovoid foramen ovale lies at the base of the lateral pterygoid plate. The ovoid foramen magnum is moderately large, and the small occipital condyles lie anteriorly on its rim. They are gendy arced a/p. The basiocciput is broad posteriorly and fairly long; its lateral margins are thickened externally, and it appears to taper anteriorly. It is also flat, with no hint of flexion, but it is "notched" laterally, near the anterior end of the occipital condyle. The palate is long but not very broad, with straight but slighdy divergent tooth rows and a continuously curved anterior part. It is moderately deep at the front, and deepens posteriorly. T h e side walls are relatively steep, and the front is sloping. From the region of the incisive foramen two parallel grooves run forward, and there appears to be a short palatal torus posteriorly. The large palatine foramina lie well forward of the posterior palatal margin. Internally, there is a long and quite stout frontal crest that fades out well in front of the cribriform plate. The plate lies well below the superiorly swollen orbital cones, in a large depression between them, and is divided longitudinally by a distinct crest. T h e anterior face of the jugal region is preserved, and its surface descends smoothly into the cribriform depression. There is no identifiable crista galli. T h e frontal lobes did not extend fully over the orbital cones. T h e region of the dorsum sellae is much broader than the tuberculum sellae, and probably bore anterior clinoid processes that overhung the deep but slighdy narrower hypophyseal fossa, which is bounded posteriorly by the vertical tuberculum sellae. As seen on the R in die middle cranial fossa, there is no superior or inferior orbital fissure. O n both sides the foramen rotundum lies well in front of the foramen ovale. As seen on the R, the groove for the middle meningeal artery arises well behind the foramen ovale, but probably still within the sphenoid. As seen on the L, the superior surface of the petrosal is flat, and there no sign of a superior petrous sinus or subarcuate fossa. T h e area of the sub-subarcuate fossa is damaged. O n both sides a

313

well-developed sigmoid sinus is preserved, though that on the R is more deeply incised than that on the L. The depression for the L occipital lobe is shallower but much more expansive than that for the R lobe. N o superior sagittal sinus is visible. As seen on the L the alveoli for 11-12 are very small, and would have housed small teeth. As seen on the R, the canine alveolus is also small, and would have housed a small tooth. The double-rooted P I and P2 would have been narrow m/d, but would have been almost as wide b/1 as M l . Sts 19. A large part of a basicranium, a damaged L zygomatic region, and a L posterior maxilla with part of M 3 , worn. Very small but adult, with a cone-shaped temporal fossa, large for the size of the skull. Zygomatic arch thin m/1 and not very tall s/i. It curves moderately in and back toward its posterior root, which takes origin over the anterior part of the acoustic meatus. T h e anterior lambdoid flows smoothly into the concave greater wing of the sphenoid, which bears a horizontal crease that delineates a large infratemporal fossa. T h e squamosal was apparendy long. As seen on the L, the articular fossa is large, very wide m/1, deep, and somewhat long a/p, with sloping anterior and posterior walls. It is bounded medially by a welldeveloped medial articular tubercle. There is a large postglenoid plate laterally that extends beyond the truncated, thin-walled, compressed ovoid ectotympanic tube that is incomplete laterally. T h e petrosals are straight and oriented slighdy medially and bear distinct pseudostyloid processes. T h e vaginal process has a low peak around the styloid pit, and on both sides it fades out laterally before reaching the meatus. Also on both sides, the small carotid foramen lies quite medial to the styloid pit, and faces down and slighdy back, whereas the relatively large jugular foramina (larger on the L) face forward. The relatively large, subcircular foramen ovale lies at the base of the probably not very distended lateral pterygoid plate. T h e foramen ovale lies well within the sphenoid, whereas the relatively large foramen spinosum posterolateral to it is bounded by the sphenoid and petrosal. As seen on the L, the mastoid is posteriorly broad and flat, and its surface is obliquely oriented laterally. It probably did not project much below the base of the skull. Damage exposes medium-to-large air cells on both sides. O n the R a shallow, possibly broad and long mastoid notch runs anteriorly down to the

,1M

S i r K IC N ri<( K s

medially placed stylomastoid foramen. The mastoid region also appears to have been distended downward a bit, following the occipitomastoid suture, but lateral to it. The foramen magnum is small, long and ovoid, and the condyles are forwardly placed and relatively large. They are not strongly arced, but bear large anterior condylar foramina. T h e basiocciput tapers somewhat forward, bears twin depressions, and is quite sharply Hexed up and forward. T h e nuchal plane is strongly sloping inward and forward. Internally, interior and posterior meningeal grooves emerge directly from the foramen spinosum. As also seen on the L, the relatively broad superior surface of the petrosal is flat and lacks evidence of a superior petrous sinus. There is possibly a small subarcu.ite "pit" and a long groove in the sub-subarcuate region that appears to come off the deep sigmoid sinus that runs to the jugular foramen. T h e preserved sphenoid sinus is quire expansive, penetrating toward the basiocciput and laterally to the bases of the pterygoids. The LM3 has a twinned and slightly truncated metacone, and a thick postcingulum running from a not very swollen hypocone. This specimen is very distinctive. StW 53d, Fragmentary, reconstructed and quite distorted R temporal, part of posterior R parietal and a bit of R occipital. Cranial bone is moderately thick. From a larger individual than the S t W 5 3 a - c pieces; also lighter in color. Although not preserving evidence of a pseudostyloid process, this specimen is included here because of similarities with Sts 5 and S t W 53g in comparable parts. This bone indicates a somewhat tall s/i and posteriorly globular braincase with straight and fairly vertical side walls and a laterally bulging supramastoid region. Greatest width is across mastoid regions. It seems that the squamosal was quite short a/p, with a broad parietal notch and apparently a somewhat long parietomastoid suture. The notch appears to have been fairly vertical. The articular fossa is deep, somewhat wide m/1 and long a/p, with sloping anterior and posterior walls. The anterior wall is steeper, and is bounded by a modest articular eminence. Posteriorly the rear wall of the articular fossa is bulged out by the transverse ectorympanic tube. Laterally the fossa is displaced outward under the posterior root of the zygomatic process, and medially it is bounded by a thin, inwardly curving flange of the temporal. There is a small postglenoid plate far laterally. A sharp

suprameatal crest flows from the supramastr' \ and into the quite strongly divergent posterior u ^ the zygomatic arch, whose superior shelf widen • riorly. T h e auditory meatus appears to have bee ° large and oval, with a well-developed supram \ crest above it. T h e tubular cctotympanic bea creaselike vaginal process along its length posteriorly this may have reached the edge of the meatus, but it lies well anterior to the mastoid process. The poster' surface of the mastoid is slightly obliquely oriented and is very broad, tall and flat The lateral surface of the mastoid process is distended by a blunt crest that runs the length of this somewhat anteriorly-directed structure. T h e process projects a bit below the skull to come to a fairly sharp point, and is separated from the long, swollen supramastoid crest by a s/i tall but very shallow sulcus. T h e mastoid notch is deep, broad and short, and is partly bounded posteriorly by a faint ridge. T h e notch is bounded medially by a low, a/p short paramastoid crest. Well medially is a slight occipitomastoid rise, and medial to this is a thin Waldcycr's crest. Anteriorly the mastoid notch flows into a depression separated by an oblique elevation of bone from a shallower depression medial and slightly anterior to it. It is difficult to determine whether either depression is a styloid pit, and it is equally difficult to identify the stylomastoid foramen. What appears to be part of the jugular foramen lies level with and medial to these depressions. T h e carotid foramen had been even more medially situated. Part of the nuchal line is preserved, and forms a bit of a corner with the more or less vertical occipital plane and the long, slightly angled nuchal plane. Internally, the moderately broad superior surface of the petrosal is quite flat, and shows no sign of a superior petrous sinus. T h e internal petrosal surface is broken. A portion of large, vertical sigmoid sinus is visible posteriorly. R occipital lobe fossa extends down quite far. Some faint but nonarborizing posterior branches of the middle meningeal artery are visible

high up. StW 53f. Included because of its possible association with S t W 53g. T h e specimen consists of p-u{ of the lateral portion of the occipital, preserving the ^ rim of the foramen magnum and part of the occiput condyle, plus the jugular notch and the anterior condylar foramen. T h e foramen magnum would n.iv been heart-shaped and relatively small, with a sht'i r. anteriorly placed, strongly arced condyle.

STERKPONTEIN

StW 5h- Fragment of pctromastoid. The mastoid process swells laterally, with a gutter between it and the bulging supramastoid crest above (cf. 53d). A low, crcaselike vaginal process lies on the posterior surface of the ectotympanic, and is separated from the mastoid process. This process is very flat and broad on its posterior surface, and probably did not extend much downward. The preserved medial portion of the ectotympanic tube bulges along its midline (cf. StW 53d). This bulge ends in a small and pointed pscudostyloid process. The stylomastoid foramen lies at the anterior end of the moderately deep and wide mastoid notch, and the thin styloid process lies very medial and somewhat anterior to the stylomastoid foramen and at the medial extremity of the low vaginal process. The carotid foramen would have been even more medially placed. The moderately broad superior surface of the petrosal is relatively flat, but with a very obliquely oriented, long and very low ridge above the region of the superior semicircular canal. Below its medial edge is a thin superior petrous sinus, but no trace of a subarcuate fossa, although there is a very broad sub-subarcuate fossa. T h e sigmoid sinus is very broad but shallow, and consistent with what is preserved on S t W 53f. Damage exposes medium-to-large air cells throughout the mastoid region, both above and below the ectotympanic. StW252sa ( = 255 + 259). Fragment of R petrosal (cf.StW252ta). StW 252ta ( = 266a). Part of L petrosal. Superior surface flat, with an oblique low rise above the region of the superior semicircular canal; there is a large, horseshoe-shaped sub-subarcuate fossa, no superior petrous sinus, the meatus is thick-walled, ovoid and vertical, and a centrally placed vaginal process runs to the lateral margin of the tube. A pseudostyloid process lies medial to the medium-sized and downwardly directed carotid foramen, which lies posterior to the vaginal process. This specimen is too large to go with the L parietal S t W 252q. StW 505 Facial M o r p h (includes Sts 71) Sts 71. Hemicranium with most of the R side and a bit of the L palate, preserving R P 1 - M 3 , broken and very worn; broken L P 1 - P 2 , alveoli for RC, L I 1 - I 2 ; partial alveoli for other anterior teeth. This specimen is possibly somewhat compressed a/p, especially at the rear. The braincase is only moderately thin-boned.

315

A narrow skull, quite domed in profile, smoothly curving right into the nuchal plane. Tall viewed from behind, with its widest point across the mastoids. From above, the R supraorbital margin retreats slightly, and straight, from the glabella. The glabella itself protrudes very slightly. There is some postorbital constriction, and a faint temporal line emerges high up and well behind the supraorbital margin. The line runs somewhat medially, then straight back and fades out level with the posterior part of the temporal fossa. The supraorbital margin is very thin s/i, and flows right into the moderate slope of the frontal with no posttoral plane or sulcus. The orbital roof is slightly concave, and flows gendy around on to the orbital rim above. Before distortion occurred, the orbit was probably subcircular, although slighdy taller than wide. T h e interorbital region was moderately broad, and apparendy flat across below the glabella. Below the zygomaticomaxillary suture lies a small depression, medial to which lies the relatively large, downwardly directed infraorbital foramen. The foramen is relatively close to the inferior orbital margin, but between the two the bone is slighdy concave. T h e upper margin of the lateral crest of the nasal aperture is thin; lower down, the lateral margin is somewhat thickened and rounded, and at this point there is a smooth transition between the nasal floor and the clivus. The inferior nasal margin is formed by the stepping down of the nasal floor to the incisive fossae right behind the nasal aperture, but the inferior margin lacks the "double gutter" configuration. In the midline there is also an a/p ridge in the position of the anterior nasal spine. There is no sign of an inferior conchal crest on the preserved R lateral nasal wall, but on the L the anterior part of a conchal crest may be preserved, well back from the aperture. In front, the inferior nasal margin flows out onto the clivus, which is short and forwardly inclined, and which lies between lateral "pillars" that represent downward extensions of the lateral nasal margins and appear to be associated with the C roots, probably having extended right to the alveolar margin. In side view the zygoma projects forward to the zygomaticomaxillary suture, at which point the forward-facing infraorbital plane becomes almost vertical. T h e anterior root of the zygoma takes origin above M l and rises steeply in front view, but does not extend far laterally. Behind, the zygomatic arch runs almost straight back. It appears that the zygomatic arch was thin both s/i and m/1. The squamosal itself

316

SITE E N T R I E S t

appears to have been very tall s/i, and was probably not very long a/p. The anterior squamosal suture angles distinctly into the temporal fossa, delineating a large anterior and a smaller posterior fossa. There is a distinct and medially deep infratemporal fossa. The articular fossa is fairly deep, and flows anteriorly over a low articular eminence. The posterior wall of the fossa is more vertical, and is directly apprcssed to the ectotympanic. It is also cupped by bone both laterally and medially. The posterior root of the zygomatic arch took origin behind the articular fossa, but flared minimally so that there is only a very short and narrow shelf above the articular fossa. The ectotympanic rube is broken laterally, but the meatus would have been fairly large, ovoid and vertically oriented. The small foramen ovale lies lateral to the large lateral pterygoid plate. The mastoid region is damaged, so that it is impossible to say how far down the process extended. However, the supramastoid and to a lesser extent the suprameatal regions are smooth and laterally bulging. Posteriorly, the cranial profile runs smoothly back into the nuchal plane, which is poorly demarcated from the occipital plane. The palate is relatively long and broad, and large for the size of the cranium. It is shallow, and does not deepen posteriorly; its walls are sloping all around. What seems to be the incisive foramen lies level with the P i s . Internally, the space behind the glabella, and to some extent laterally over the orbit, contains a sinus that descends to the frontomaxillary suture and extends laterally at last one-third of the way across the orbit. The frontal lobe does not extend fully over the orbital cone. The large maxillar)' sinus penetrates far into the zygoma. The teeth are broken and heavily worn. The alveoli for LI 1-12 are small and would probably have had small crowns. The C alveolus is relatively large. P I was probably shorter m/d than P2, and both were not much narrower b/1 than M l . M l and M 3 are subequal in size, and smaller than M2. On M 1 - M 3 the protocone was both markedly mesially situated and markedly distended lingually. The hypocones were large and m/d long on all Ms, and most d/1 distended on M 2 . StW 505. Most of L cranium, with part of R supraorbital region and maxilla; somewhat damaged and distorted and reconstructed. The braincase bone is quite thick. This is a relatively long neurocranium with a low frontal rise and a smooth curve across its top, the

sagittal profile gently sloping back to its junction with the strongly inward-curving nuchal region. In profil glabella markedly overhangs the lower face (which was probably more gently dished than distortion ' makes it seem). From behind, the braincase was prob- ' ably quite tall, with almost vertical sides that sloped infcriorly lateral to the slightly expanded mastoid regions. The greatest cranial breadth would have been across the mastoid regions. The better preserved R supraorbital margin arcs gently from side to side. It is not very tall s/i, but is not thin (unlike StW 252o). The anterior surface of the margin curves smoothly back in profile, forming a blunt angle with the very shallow superior roof of the orbit. O n both sides, the medial portion of the supraorbital margin is swollen somewhat superiorly (these two low elevations delineate between them a shallow but wide m/1 depression that forms the postglabellar plane); bilaterally, the margins curve anteriorly down onto the broadly and anteriorly swollen glabella (thus forming a shallow, vertical midline sulcus along the face of the glabella). W h e n viewed from above, the broad glabellar region protrudes markedly in front of the supraorbital margins, which angle back quite strongly and then straighten out somewhat laterally. A small, healed compression fracture lies not far behind the glabella; there is another compression on the L parietal. O n the R (seen from above), the supraorbital margin is indented slightly just medial to the midline by a narrow but relatively deep supraorbital notch. T h e temporal line (preserved on the R) is raised and comes up high onto the frontal plane; it courses strongly medially, delineating a slightly raised (not sunken) frontal trigon. The supraorbital region flows smoothly into the rather steeply backwardly inclined frontal plane. As seen on the R, postorbital constriction is severe; a large portion of the lateral wall ol the orbital cone faces upon the temporal fossa. The orbits were apparently tall and roundedly rectangular, and are separated by an extremely broad interorbital distance that is further broadened inferiorly by the forwardly facing posterior lacrimal crests. T h e nasal bones are extremely tall, and thin; they appear to have broadened slightly at their inferior extremities. The frontonasal suture lay at the sunken base of the tall glabellar region (thus the nasal bones appear to be shifted downward, the nasal aperture consequently being well separated from the interior orbital margin, a configuration also reflected in the tall infraorbital plane). The frontal processes are rorwardly

STERKPONTEIN

I

,

facing and, along with the nasal bones, appear to have formed a flat interorbital plane that is truncated by the medially placed anterior lacrimal crests. The orientation of these crests causes the long lacrimal grooves to face forward. As better seen on the L, the infraorbital plane was oriented anteriorly, while in profile it was probably vertical. The infraorbital foramen is downwardly facing; it lies well below the inferior orbital margin, and lateral to a low pillar that had extended down to alveolar margin of the C. A slight sulcus courses immediately below the infraorbital foramen; the side of the facial pillar apparendy coursed straight back (i.e., there was no well-defined canine fossa), thus delineating a snout or muzzle inferiorly. The anterior root of the zygomatic arch is straight. It takes origin near the alveolar margin of the Ml and in the plane of the infraorbital foramen, and extends up and strongly laterally to turn almost straight back at the ill-defined maxillary tuberosity. The masseter scar faces quite laterally. The nasal aperture is broad inferiorly and relatively tall; it was probably much narrower above. T h e facial pillar does not extend fully up the side of the nasal aperture. As seen on the L, the lateral crest of the nasal aperture is blundy angled from inside to out for much of its length. T h e margin of the lateral crest turns sharply medially (but in a continuous curve) at the inferolateral corner of the aperture. T h e bone in this region is also rounded from inside to the exterior of the nasal aperture. T h e nasoalveolar clivus is relatively straight and not very long; it slopes down and forward, and behind it flowed smoothly down and into the apparently moderately stepped nasal cavity floor. This "step" is (and thus the incisive fossae were) near the front of the nasal cavity. N o anterior nasal spine is apparent. The squamosal is long and was probably low. A t the front it seems to have turned sharply but roundedly inward into the temporal fossa, along a slighdy posteriorly inclined axis. It is impossible to determine if temporal and infratemporal fossae were originally demarcated. A t the posterior edge of the squamosal, the parietal notch is moderately oblique. T h e petromastoid edge is rather short. T h e articular fossa is fairly deep, and long a/p, with very sloping anterior and especially posterior walls. T h e anterior wall of the fossa rises over a low articular eminence. This eminence continues medially into a medial articular tubercle that truncates and partially closes off the fossa medially. W h a t appears to be the foramen spinosum

317

lies anterior to the medial articular tubercle, and apparently lateral to the lateral pterygoid plate. The foramen ovale is not identifiable. The auditory meatus is quite large, almost circular, and a shallow sulcus lies quite medial to the meatus. The cctotympanic tube apparently bore a long, low vaginal process for most if not all of its length. There is very little detail visible on the inferior surface of the tube. The L mastoid region is somewhat damaged; its posterior surface is flat, m/1 expansive, and faces down and slighdy back (thus forming essentially a cornered angle with a small laterally facing portion). There is a moderate mastoid tubercle on this lateral surface, situated just behind and above the level of the bottom of the auditory meatus. Superior to the mastoid tubercle the bone swells again, above a shallow gutter, into a low, broad, horizontal crest that continues forward into a very low suprameatal crest. The palate is crushed; it was shallow anteriorly and not very deep posteriorly, and was probably fairly narrow between the Cs. The incisive foramen lies level with the P i s , and apparendy continued forward along a groove with a low central keel. The posterior pole of the maxilla is very tall s/i. Very damaged L P 1 - M 2 , plus alveoli for R C - L C , are preserved. The 11-12 alveoli are relatively small and subequal in size; the C alveolus is larger (but not extremely so). Internally, the anterior cranial fossa is long. The orbital cones stand out and are separated by a broad, deep fossa that tapers toward the region of the cribriform plate. Apparently, the supraorbital region was pervaded by a large sinus that runs back at least as far as the level of the postorbital constriction. The frontal lobes did not extend fully forward over the orbital cones. The frontal crest is long and well developed. It seems that (as seen on the R) the lesser wing of the sphenoid is backwardly projecting, and overhangs the short superior orbital fissure. The inferior orbital fissure is represented by an oval foramen. The hypophyseal fossa was apparendy horizontal, and enclosed by the tubcrculum sellae. As seen on the L, the middle cranial fossa is quite deep. The groove for the posterior branch of the middle meningeal artery arises along the lateral margin of the broad, flat-surfaced petrosal.

SK 48 Facial Morph (includes S t W 53) St\V53 Cranium in fragments, a-g. StW53a is a damaged frontal region, b is a lower face. After

318

SITE

renumbering: 53a is a frontal; 53b a maxilla with teeth, b/a-i\ c is part of the R zygoma; d is part of R temporal, posterior parietal and lateral part of occipital; e is part of L parietal and possibly the adjacent portion of the o c c i p i t a l i s the lateral part of the L occiput; £ is a damaged L petromastoid; h is part of the R ramus preserving the tip of the coronoid; / is a possibly associated isolated lower left M 3 . StW 53d is much lighter in color than the rest, and not all bits may represent the same individual. StW 53d, f and g are described in the section on the "pseudostyloid morph," and 53c and e and described under Unassignable to morph." S t W 53a possesses the very thin, slightly laterally thickening supraorbital margin that is so distinctive of SK48 and SK 79. StW 53a. This frontal is damaged and reconstructed, preserving the R superior orbital margin and most of the midsection of the bone. It is rather thickboned for a skull this small. T h e superior orbital margin is unusual in bein? very thin and short s/i; medially there is a large supraorbital notch, from which the margin thickens s/i laterally. T h e glabellar region was probably quite broad and anteriorly swollen. Looking down, glabella is emphasized by the posterior curve of the superior margin in the region of the broad supraorbital notch. More laterally, the superior margin projects further anteriorly, becoming level with the glabellar region. Postorbital constriction was probably quite marked. T h e superomedial corner of the orbit is "cut off," being truncated by a superiorly thickened interorbital pillar. Immediately lateral to this the superior margin is indented a/p and thin s/i, though it thickens slightly laterally. Medially it is thinned by a wide notch below. T h e zyeomaticofrontal suture faces quite laterally, rather than down. The superior orbital roof is distinctly concave, and curves back sharply into a posttoral and postglabellar slope, behind which there is an only modestly rising frontal slope. The frontomaxillary suture is oriented anterolaterally. It suggests that the frontal process was turned out somewhat, and did not face forward like that in the maxillary' fragment from the R (thus representing a different individual than S t W 53b?). A small portion of the R nasal bone is preserved in 53a, and in profile it is quite turned-out and projecting. This is not consistent with the flat nasal bones of the fragment representing the lower face (again suggesting a different individual). Postorbital constriction is fairly marked, and on the R is visible a thickened

ENTRIES

bandlike temporal line that arises behind *k supraorbital margin, creating the "corner" of a fron \ trigon. The interorbital region on the frontal W ^ J J have curved from side to side, while that on th maxilla would have been flat across. On the R onH T the temporal lines curve back from their ori»inparallel to the midline; they do not converge. Behind' the frontal is slightly domed in the posterior midline of the frontal trigon. A large sinus that was probably divided in the midline by a septum pervades the region of the posttoral/postglabellar plane and, as seen on the L, descends down in front of the re<non of the frontal lobe, between the bone of the orbital cone and that of the anterior cranial fossa. This suovests that the sinus may not be of ethmoid origin. Bilaterally the sinus extends to the temporal lines, and posteriorly to the rear of the frontal plane. Internally the frontal crest was long and thick, and the frontal lobes were separated anteriorly by a large, deep fossa. As seen on the L, the frontal lobe did not extend fully over the orbital cone. O n the frontal, above the L temporal line, there is a small, healed, apparently traumatic depression.

D N H 7/SK48-Like Upper Dental/Facial Morph (includes Sts 53 and S t W 53b) Although the specimens described in the following paragraphs have upper dentitions that are more than strongly reminiscent of the upper dentitions ot DNH 7 and members of the SK4S upper dental morph (especially in premolar-molar proportions and details of molar morphology), aspects of the lower face of these two Sterkfontein specimens militate against assigning them to either of these facial morphs. For instance, in both Sts 53 and S t W 53b the anterior root of the zygomatic arch originates quite close to the alveolar margin and, as better seen in the latter specimen, strongly and very arcuately turns out laterally (rather than sloping gently up and broadly laterally). In addition, the nasal apertures of Sts 53 and StW 53b are quite broad inferiorly and, as suggested in the former specimen and seen in the latter, the lateral crests (margins) converge inward to form a rather low and broad nasal aperture (rather than a tall and interiorly narrow nasal aperture). Also as seen in StW 5^b, the inferior margin of the orbit is low-set relative to the nasal aperture (rather than above it) and the infraorbital foramen lies close to it (rather than well below it).

STERKFONTEIN

5/5 53. Fragmented and largely reconstructed maxilla with lower part of the nasal region and anterior root of the R zygomatic arch. Also alveoli for RC-LI1, alveolus for L C , roots of LI2 and R P l , anterior root and buccal part of crown of RP2, damaged crown of LP2, and R and L M 1 - M 3 ; all teeth rather worn, M l most heavily. The palate is not large; the teeth are in proportion. The anterior teeth are large relative to the cheek teeth. The lateral margins of the nasal aperture are rounded; the inferior corner apparendy curved smoothly inward. T h e inferior margin is relatively broad and is delineated by very low crests that run laterally from die midline. Behind the inferior margin the bone steps down into the nasal cavity. T h e exposed R incisive fossa lies close to, and not far below, the inferior margin. T h e nasoalveolar clivus is relatively short, and curves out and down from the inferior nasal margin. As seen better on the L, a trace of vertical swelling follows the C alveolus; this swelling may have continued as a pillar above. As seen on the L, a moderately developed C fossa lies between the bulge of the C root and the anterior root of the zygomatic arch. The root of the arch appears to have been facing forward, and takes origin above P2. T h e palate is relatively long and narrow, with a long, gende slope behind the Is to the relatively large incisive foramen, which lies about level with the P i s . T h e front of the dental arcade curves across quite strongly. T h e palate becomes a bit deeper posterior to the incisive foramen. A pair of shallow grooves runs forward from the incisive foramen to the region of the l i s . As seen on the R, the greater palatine foramen lies level with M 3 , and is quite medially situated. T h e I roots were not very long or very stout; the C roots apparendy were. As seen on the L, the P i is two-rooted. Judging from the broken R P l , the crown was short m/d, as apparendy was the crown of P 2 . As seen on the R, P2 is two-rooted. Apparendy P 1 - P 2 were both as wide b/1 as M l . M l is slightly smaller than M 2 b/1 and m/d, while M 3 is slightly smaller than M 2 m/d. Judging from the R, the metacone decreases in size m/d from M l to M 3 , while the hypocone increasingly fills out the d/1 corners of M 1 - M 2 ; at least on R M 2 - M 3 the relatively large protocone is mesiaUy shifted. As better seen on the L M 1 , the hypocone extends a bit more Kngually than the protocone, but apparendy did not swell the tooth discally as on the L M 2 . As seen on the RM2, the hypocone is compressed m/d and extends buccally to contact the internal side of the metacone; a

319

very b/1 short and m/d thick postcingulum courses from the hypocone and parallel to it to the internal side of the metacone. O n the RM3 the very m/d compressed hypocone extends directly up to the very small metacone, from which it extends a bit distally. The L M 3 is oddly configured, with the hypocone being minuscule while a very thick and beaded postcingulum courses arcuately around the internally placed metacone to terminate in a stylelike projection on the buccal side of the latter cusp. The lingual side of this tooth bears a series of marked vertical grooves. St\V 53b. Maxilla and lower face, with most of the nasal aperture. Broken off below nasion, but part of the frontomaxillary suture is preserved on the L, and was quite low down. Nasal floor is missing. In profile the preserved portion of the nasal bones is shallowly concave, suggesting that the glabellar region would have been anteriorly protrusive. In the frontal view the gendy inferiorly widening nasal bones are slighdy sunken compared to the L frontal process. T h e interorbital region was moderately broad. The nasal bones bear a slight median keel that does not extend to their inferior margins. Lateral to the superiorly sharp lateral crest of the nasal margins a low, rounded thickening of bone descends below the inferior margin to become confluent with the bulge of the C root. The preserved plane of the infraorbital region is vertically oriented and anteriorly facing. The lateral crest becomes blunt and rounded inferiorly. As seen on the R, the anteriorly facing and vertical s/i infraorbital plane is slighdy concave lateral to this thickening. A frontal process foramen lies in this shallow depression near the inferior orbital margin on the L. Somewhat posterior and lateral to this is part of the margin of the relatively large infraorbital foramen, lying quite close to the inferior orbital margin. The foramen probably had a groove descending from it, and it apparendy lay in a depression as well. The inferior margin of the orbit is preserved; it angles down and laterally. As reconstructed, the anterior root of the zygomatic arch takes origin close to the alveolar region of M l and curves out strongly laterally. Also as reconstructed, the zygoma itself would not have been wry tall. The moderately large (for the size of the specimen) nasal aperture is w r y broad at its base compared to its height, and is quite narrow superiorly. Its inferolateral corner is blunt and rounded. The lateral nasal wall on the R side bears a distinct conchal crest, low down and situated well back. The relatively flat and long nasoalveolar clivus

320

SITE

descends steeply from what was apparently an obtusely angled junction with the floor of the nasal cavity. There were apparently quite bulky anterior nasal spines, well behind and below which arc the large and backwardly facing incisive fossae. There was thus some stepping-down into the nasal cavity: The maxillary sinus on the R penetrates far into the nasoalvcolar clivus, and on the L posteriorly beyond the M 3 . On the R is a very long, posteriorly incomplete lacrimal groove, probably roofed by bone. The palate is shallow anteriorly, and deepens posteriorly only modestly, with sloping sides. The large, depressed incisive foramen lies level with P2, and continues anteriorly to the base of the incisors as a depression with a bony midline ridge. As reconstructed, the dental arcade is relatively broad, gently curved across the front, and parallcl-sidcd. Teeth. R P 1 - M 3 , heavily worn and slightly damaged; LP1-P2 and M 2 - M 3 , heavily worn, damaged; alveoli of R C - L I 2 as well as L M l . T h e anterior tooth alveoli are large, especially that for the canine. All anterior teeth would have been very long and stoutrooted; also probably large-crowned. There was probably only a little incisor hcteromorphy. PI and P2 are both divergently three-rooted, and the crowns were much wider b/1 than long m/d. Both had some stylar development on either side of the paracone. P2 was slightly longer m/d than P I . The Ms increase in size from M l to M3, the Ps appearing large relative to M l . At least M2 and M3 had a large hypocone, which was less lingually distended on M 3 than on M2. The M 3 hypocone was compressed m/d and extended buccally to contact the internal aspect of the small metacone. A m/d thick but b/1 short postcingulum coursed from the end of the hypocone to the distal side of the diminished metacone. There is also a deep pit distally on the lingual surface of the M3 protocone. StW 151 Upper and Lower Dental Morph (includes StW 14 and 104) StW 14. Crushed partial mandible with some of L and most of R corpus, and a bit of R ramus. Has L P 2 - M 3 , worn, broken and crushed; RP1 and M 1 - M 3 ; and damaged alveoli for other teeth. The PI is wedge-shaped with an anterior fovea that opens lingually between a stout cristid and the metaconid. The postincisal plane is moderately long but very gently sloping; there is a sharp drop-off below into a deep pit, and a probable inferior transverse torus below.

EXTKIES

The corpora are narrow m/1. The anterior root of \h ramus rises sharply distal to M2, obscuring mo M3, and there is no gutter. The I roots were p ro b VJ quite compressed, and the C roots quite small. ^ PI is a bit smaller overall than P2. It k c:,,u* • u • i-v 11 i * Dtnangular in outline with a tall, pointed, centrally pla J protoconid and slightly smaller, lower and mesiall • situated metaconid. The two cusps arc connected b tall, thick cristid. In buccal profile the distal edge' * slightly longer m/d than the mesial edge, and both are quite divergent. There is also a distinct mesial lingual pillar. A stout, short cristid runs from the mesial pillar partway across the front of the tooth lingually, and terminates at a notch between it and the metaconid that opens the small anterior fovea lingually. A much more robust distal cristid runs to the base of the metaconid and swells the base of the tooth d/1; there is no distal fovea or basin. On the P2 the lingual side of the tooth is longer m/d and more rounded than the buccal side. The protoconid is large and slightly mesially shifted, while the subequal metaconid lies slightly mesial to it. There is a small anterior fovea and a moderately larger posterior fovea bounded by a thick and slightly arcing distal cristid. The buccal side of the tooth slopes gently. M l may have been wider b/1 than M2, but was apparently shorter m/d. M 3 is the largest of the three Ms, especially m/d. M2 is somewhat rounded distally; M 3 is a little straighten M2 and especially M 3 are modestly cuspulated, with long, filledin talonid basins and small but distinct anterior foveae, and metaconids that dominate in height as well as in m/d length (longer on M3). A paracristid courses low down just across the bases of the protoconid and metaconid on M2; it is slightly less pronounced on M 3 . O n M 2 and even more so on M3 the hypoconid base is blunt; on M 2 it just crosses the midline of the tooth to abut only the b/1 truncated entoconid, but it contacts the long metaconid and even smaller entoconid on M 3 . On M2 the hypoconulid lies mostly buccally; on M 3 three small cuspulids lie centrally, separating the buccal hypoconulid from the larger lingual entoconid. There is a large cuspulid intervening between the larger metaconid and entoconid. As seen on M 3 the molar cusps are low and puffy, but not well defined as in teeth from Swartkrans. StW 104. Fragment of L mandibular corpus with a very worn d m l and a moderately worn dm2, plu> a C crown deep in the bone. Corpus is quite tall s '

STKKKFONTBIN

. f i v e t o tooth height, and is also broad m/1. A 'dcratcly sized mental foramen lies quite far below I ?° mcs ial portion of dm2. Part of the inferior border ! prcScrved; it slopes upward posteriorly. Internally *h re is no sign of a mylohyoid line, but there appears be a shallow submandibular depression low down. The internal curvamrc is much stronger than the t c r the inner surface begins its curve near dm2. The C crown is partially obscured, but is not large for this sample. It has a pointed apex with a fairly long, ply sloping mesial side, but halfway down the crown curves back toward the neck. There is a pronounced vertical lingual pillar running down from the apex, and between it and the mesial edge is a long, tall moderately deep depression. The pillar swells out toward the neck into a flat heel, d m l is small relative to dm2. dml narrows mesially and is somewhat exodacnodont over the mesial root. The paracristid apparently went obliquely down the front of the protoconid before turning back and down as a thick ledge to the base of the metaconid. Thus the shallow and vertically oriented trigonid basin faces m/1. T h e protoconid is the largest cusp; it is huge at its base, especially b/1, and was probably also the tallest cusp. The metaconid is appressed to the side of the protoconid and a small entoconid lies distally at its base, separated from it by a wide notch. T h e entoconid is small, and so was the hypoconid, which lies opposite and slightly mesial to it. T h e small talonid basin was probably somewhat constricted by these cusps to face d/1 or just lingually. There is some buccal cingulid around the protoconid; the enamel is broken off the hypoconid. T h e dm2 is a relatively long and somewhat ovoid tooth, with an m/d narrow basin confined by a thick paracristid and the bases of the protoconid and metaconid behind. Behind this basin, and between the protoconid and metaconid, is another small basin. T h e buccal cusps are more bulbous and their apices more internally placed than the lingual cusps, which also lie slighdy distal to them. There is a roundedly blunt, semi-wedge-shaped hypoconid of moderate size that extends a bit buccal to the midline to contact both the very m / d long metaconid and the distally shifted, m/1-oriented and wedge-shaped entoconid. T h e hypoconid was apparendy also separated from the hypoconulid by a notch. Between the hypoconulid and the entoconid is a small but deep fovea with a ledge distal to it that faces d/1. There are traces of a thick cingulid on the buccal side of the protoconid. fC

321

St\V 151. A piece of a L maxilla with very worn d m l - d m 2 and the erupting 12. All teeth arc fairly small especially the dms. The dml has a somewhat mcsiaUy and peripherally placed paraconc with notable mesial distension of the parastylar region and a larger mctastylar region that is probably the terminus of a thick postcingulum; there is a slight crease on each side of the cusp, between it and a stylar region. The dml protoconc was quite large and probably somewhat internally placed; the parastylar region projects mesially much farther than the side of this cusp, producing a concave mesial surface. The buccal cusps of the m/d and b/1 larger and subsquare dm2 arc peripherally placed, and the m/d long metaconc is noticeably larger than the paraconc. The very large protoconc is somewhat mesially shifted and is markedly distended lingually, thus contrasting with the b/1 much shorter hypoconc; these two cusps arc also separated by a broad wedge-shaped notch. The fairly high-crowned, erupting 12 bears margocristae and a concave lingual surface; its incisal edge very smoothly curved. T h e similarly shaped isolated R12 and the very tall and narrowly spatulated R and L l l s can plausibly be associated with the L12, as also can the small, pointed LC. This tooth has subequal, long and steep mesial and distal edges, as well as two very thick lingual pillars (distal is quite s/i short, the mesial courses more than halfway up the crown), which diverge from the swollen base lingually, bounding a depression between them. T h e unerupted RP2 possesses a relatively large and subovoid crown, almost as wide b/1 as the M i but much shorter m/d. T h e tall and dominating protoconid lies somewhat mesially, and the lower and more m/d compressed metaconid is situated even more mesially. A moderately thick crest courses from one cusp apex, down the internal side of the crown, and up the other cusp to its apex. A very stout paracristid arcs mesially from one apex and back to the other; it stays almost horizontal and at cusp-apex height, thereby encircling a fairly deep, b/1 wide, m/d long, upwardly facing anterior fovea. A n extremely thick postcingulum is separated from the distal side of the protocone by a small, low, wedge-shaped structure (and thus a notch also is created below this structure). T h e thick postcingulum courses essentially straight to the d/1 corner of the tooth to form a broad u V" with the distally truncated base of the metaconid. T h e buccal surface of this tooth is more bulbous than the straightcr lingual side.

f

V>o«

">.-.* -\

^S**"

i i

322

Si TIC E N T R I E S

}i

The relatively small, worn, isolated R and LM1 (which can also plausibly be associated here) are similar to the dm2s in having the protocone more lingually distended than the hypoconc, but this disparity' is not as profound as in the latter teeth. In both Ms, the large, internally expansive protocone bears a distinct expanse of cingulum on its mesial side, and a fairly deep, vertical notch separates it from the smaller but still relatively large hypocone, which extends more distally than the mctacone; a relatively short and buccally widening postcingiilum emerges from the distal part of the hypoconc and terminates on the distal side of the mctacone. This latter cusp is larger m/d than the paracone, which either has a thick prccingulum along its mesial side or what has not been worn away of a very mesiallv coursing prcprotoerista. A d/1-oricntcd horizontal groove on the distal margin of the protocone may represent what remains of a postprotocrista that coursed to the internal surface of the metacone. The M2s of StW 151 arc minimally worn, yvith heavily cuspulated enamel. Their lingual slopes are long, with the lingual cusps more internally placed than the buccal cusps. A relatively short preprotocrista runs mesiallv around the side of the paracone. A thick, cuspulated postprotocrista runs toward the small and lingually and arcuately truncated metacone; a metaconule-like structure lies at its base. The very thick, short postcingulum arcs from the distal side of the distally swollen, wedgelike hypocone to the side of the metacone, enclosing a small, deep talon basin. There is a protostylar pit and ledge loyv down on the protocone. In contrast to the M i s , the paracone is larger m/d than the metacone, the protocone and hypocone are level yvith each other lingually, the hypocone is much smaller (especially m/d) and the postcingulum appears to be b/1 longer. The M2s do possess the b/1-oriented, horizontal groove on the distal margin of the protocone and some cingulum on the mesial side of the protocone also seen on the M i s , and can plausibly be associated with them. There is a fragment of R corpus containing very worn dm 1 -dm 2 and a slightly worn M l and showing P2 deep in the bone. There is also a L mandibular fragment with which are associated d c - d m 2 , with P2 in its crypt and M l erupted. A small part of the anterior part of the ramus is represented, and its edge arcs up steeply. The Rdml was apparendy wedge-shaped, with the protoconid being much more mcsially placed than the metaconid; the front of the protoconid is even slightly centrally positioned, and wraps a bit around the base of

the metaconid. The protoconid is somewhat ex i odont. Only the large metaconid remains distinct T\^ was a very large, somewhat vertically and m/1 0r- Crc trigonid basin between the protoconid and mcta • i At the base of the metaconid distally is a small conid on to which a modest and vertically and d/1 •" entcd talonid basin faces. There is a notch between K protoconid and hypoconid. dm 2 is an m/d long and b/1 narrow tooth that is considerably larger than the dml i probably had a very mesial trigonid basin with a small basin behind it. The metaconid was much larger th the protoconid, especially m/d, while the reverse wa true of the cntoconid and hypoconid. The moderately sized hypoconulid was more or less centrally placed with a bit of buccal extension; there may have been a shelf or cristid between this cusp and the distally truncated cntoconid. The R and LMls have somewhat bulbous cusps, yvith the buccal ones being somewhat more bulbous on their sides than the lingual ones, which arc more peripherally placed. There is a yvedge-shaped groove (wider mcsially) between the bases of the protoconid and m/1 longer metaconid. On the L there is a mctastylid on the side of the metaconid, and one sandyviched between this cusp and the b/1 compressed cntoconid; only the second configuration is seen on the R. The base of the somewhat large and yvedgc-shaped hypoconid extends across the midline and nestles just between the bases of the metaconid and cntoconid. The smaller but also wedge-shaped hypoconulid is situated just buccal to the midline and the apex of its base angle m/1 to contact the entoconid. There is a fairly b/l wide cristid, yvith a parallel groove just in front of it, between the yvell-separated bases of these two cusps. There are also isolated R C - I 1 and LI1 that appear to be reasonable antimcrcs to the upper anterior teeth we associated yvith this morph. The RC is similar to that of S t W 104. The I l - I 2 s arc fairly tall crowned and relatively rather narrow b/1. The lis are less flaring and laterally rounded than the I2s. There are also very yvorn, very small lower deciduous teeth. The dc retains a hccl-like distal margocristid and a smaller mesial one. The apex was probably quite mcsially placed. M L D 2 Lower Dental Morph (possibly includes S t W 327,404 and perhaps also S t W 451) StW 327. L partial corpus with a bit of ramus and P 2 - M 2 . M l is the most worn. Damaged PI alveolus and root.

[

S T IS R K F O N T131N

Subadult with narrow and shallow jaw b/1. Ramus c qUite steeply, probably at the level of M l . Interillv there is a very strong vertical pillar confluent ith the internal alveolar crest, and there is already a hint of a gutter. The large, compressed mandibular foramen lies behind the internal crest and well above the level of the cheek teeth, and points back. There is no trace of a mylohyoid line, but there is a hint of a submandibular fossa. The preserved part of the gonial rerion is quite thin and appears to have had a rounded angle. PI was probably shorter m/d than P2, though possibly wider b/1. P2 is quite large relative to M l , which is small b/1 and especially m/d relative to M 2 . P2 is longer m/d than wide b/1, and is slightly narrower mesially than distally. The peripherally placed metaconid lies mesial to somewhat internally placed and rather mesially situated protoconid and is also slightly smaller than the latter cusp. T h e two cusps are connected by a short, stout paracristid that encloses a deep anterior basin. Vertical grooves on the somewhat bulbous buccal side suggest a mesial pillar and distinguish a thick distal cristid from the protoconid. This cristid runs straight along the distal side of the tooth and contacts the metaconid, enclosing a fairly large but shallow talonid basin in which there is some wrinkling. M 1 - M 2 are long m/d and relatively narrow teeth. M l is quite worn, but as in M 2 the lingual cusps, especially the metaconid, are taller and more peripheral than the slightly more internally placed buccal cusps. The broad M l hypoconulid was centrally placed and runs a bit buccally, and its lingual and distal extremities are delineated by moderately thin but distinct notches that appear to cut this cusp off from the cusps on either side of it (cf. M L D 2). There is a pit between the protoconid and the wedgeshaped hypoconid, whose base extended slightly beyond the midline to contact both the metaconid and the entoconid, and there was probably also a small antenor fovea and a paracristid mesially. M l is broad distally, while M2 tapers. On M 2 the buccal side as well as the occlusal surface is wrinkled, and the hypoconid is configured as on M l . There is a thick paracristid and a short, low, d/1-facing, notably pitted cristid between the small, fairly buccally placed hypoconulid and the small entoconid (cf. M L D 2). StW 404. R mandibular corpus with associated P I and P 2 - M 3 , plus R and LC roots and part of LM3. P 1 - M 2 are quite worn; M 3 is not.

323

The corpus is small, shallow, and relatively broad for its depth. There is a shallow genial pit with a small torus beneath. T h e front of the jaw sloped up inferiorly. The toothrows are narrowly curved at front and minimally divergent behind. There is a single mental foramen below P2. The corpus broadens b/1 posteriorly and there is no mylohyoid line or submandibular fossa. There is very faint scalloping in the region of the digastric fossae, which point somewhat back. The inferior border arcs upward in the symphyseal region. The anterior teeth would have been very b/1 narrow. The wedge-shaped P I is smaller than P2, especially m/d, with three compressed roots. It is obliquely truncated m/1 (forming a mesially squared-up triangular oudine), with a strong mesial and somewhat smaller distal pillar on the somewhat swollen buccal surface. There is a deep, small anterior fovea that opens lingually via a notch, and a larger but shallower posterior fovea. The protoconid is peaked and somewhat mesially placed, with a long divergent distal edge and short mesial edge. There is evidence of a lower, peripherally placed, and slighdy more mesially placed metaconid. The protoconid bears a short but stout mesial cristid that angles in sharply at the buccal pillar, and terminates at a notch or crease that separates it from a crest that comes down lingually off the protocone. A longer, stouter distal cristid runs to the distended d/1 part of the tooth. P2 is longer m/d, and the subequal protoconid and metaconid lie opposite and very mesially. There is a small anterior fovea and a larger and somewhat deeper posterior fovea. T h e d/1 corner is somewhat squared up, apparendy by what had been a thick cristid that coursed from the distal side of the somewhat buccally bulbous protoconid; this cusp bears a low but distinct mesial pillar and a small distal pit. All Ms are long m/d and rounded rectangular; they increase in size, especially m/d, in the sequence M 1 - M 3 . Although M 1 - M 2 are quite worn, they still preserve evidence of the m/d thick paracristid and well-developed protoconid buccal cingulid seen on M 3 . Also detectable on M l is the wedge-shaped hypoconid that just crosses the midline of the crown to contact both the metaconid and entoconid (the base of this cusp is a bit blunter on M2) and the b/1 wide and m/d long wedge-shaped hypoconulid that broadly straddles the midline of the tooth (similar in M 2 , which also preserves on the buccal side a notch between the hypoconulid and hypoconid). On M 3 , the hypoconid base is quite blunt and only contacts the fairly m/d long entoconid, and

1

324

SITE

the large, centrally placed hypoconulid is subdivided by a midline crease that represents the crenulation still visible in the very m/d long, somewhat b/1 wide, and rather shallow talonid basin. There are also deep vertical fissures between the protoconid and hypoconid, and the metaconid and entoconid. A fragment of LM3 is a good match for the R. StW 451. Is a RI1 or 12, with compressed root broken at tip and some wear. This is a narrow, minimally flaring and lingually swollen tooth, and was probably tall-crowned. Somewhat concave in lingual profile. Suggested to belong with S t W 404. Nonhominid/Powg-o-likc Morph: Upper and Lower Dentitions StW 277. Large, slighdy worn L M 3 crown, with very sloping buccal and lingual sides and the roots missing. All cusps are incorporated into a cresting ring around a large, not very deep, thickly crenulated basin with no distinction between trigon and talon basins. The m/d long protocone region is shifted mesially and appears to bear slight traces of lingual cingulum. T h e metacone region is low and obliquely oriented; it "flows" into the large hypocone (thus, the buccal side of the tooth is markedly truncated). T h e hypocone greatly swells the tooth distally, but does not quite extend as far lingually as the protocone. T h e perimeter of the tooth bears vertical pillars and grooves, particularly between the protocone and hypocone regions. The compression of cusps into a cresting system that rings a thickly crenulated basin, as well as the coloration and degree of wear, suggests that this tooth is the upper counterpart of S t W 278, a lower molar. StW 278. This is an isolated, slighdy worn R M 3 (or M 2 ) crown; roots are broken off. The tapering m/d long crown is only slightly b/1 narrower distally than mesially. The buccal side is quite sloping; the Ungual side is more vertical. T h e cusps are compressed (the most distinct being the peaked metaconid) and bear cristids on their sides. Cristids running mesially from the protoconid and the metaconid swing internally, to meet at the midline, and enclose an m/d long, b/1 wide, deep, and thickly crenulated trigonid basin. There is a large metastylid and a well-developed buccal cingulid around the base of the protoconid. The buccal and lingual "cusps" lie opposite one another, the beaded hypoconulid (cf. Drimolcn)

ENTRIES

occupies most of the back of the tooth wh* k • and tapers somewhat distally. ** ^°ng Unassignable to Morph Sts 7. Crushed and highly weathered mand-fci missing most of L ramus and inferior part of R Some remnants of R ramus are there but inH * u*" able. L M 3 - R M 2 are in various states of extrem ? **" and damage. This is a fairly tall but not very lam - ^ Symphyseal region is fiar, it angles back and d o ^ profile. The postincisal plane was probably W !J gendy sloping. The Is were apparendy narrow. As <^n on the L, the C was stoutish. The Ps seem to have be large, especially in b/1 width, and the molars increased in size from M l to M 3 , especially in m/d length. The M 3 is a b/1 broad tooth, broadly rounded distally. The M s were probably not very small. Sts 36. Lower jaw, somewhat distorted and reconstructed, with LI1 and C - M 3 , and on the R broken roots and M 2 - M 3 . All teeth heavily worn. Very distinctive, with large M s . Large but not massive mandible. Corpora are only moderately deep, and are not extremely broad m/1. T h e symphyseal region was probably quite tightly curved seen from above, and in profile the symphysis is straight and slighdy tilted back. Apparendy the postincisal plane was quite short and sloping; it is broken below. O n the R is preserved a very small and inferiorly facing digastric fossa. Other internal detail of corpora is obscured. T h e rami rise steeply from the junction of M 2 - M 3 , and partially obscure M3.The gutter between the posterior molars and the rami is narrow. T h e internal alveolar crest rises posteriorly as a stout torus to bifurcate above the level of the tooth row into two low, thick crests, one running up the middle of the coronoid region, the other toward the condyle. T h e moderately large, upwardly pointing mandibular foramina lie behind and below the juncture of these crests. Most of the coronoid processes are missing, but the sigmoid notch was moderately deep, not very long, and ran just medial to the lateral extremity of the condyle. T h e condyles are bulk}' but narrow m/1, and are a little bit rounded on their posterior surfaces. T h e rami are not very tall, and the gonia region is smooth except for some minor scarring ^ the inferior margin both internally and externally, angle itself is almost right-angled. T h e teeth are very worn and shattered. * n e . was quite a large tooth, and was originally
-

S TK R K FO NTEIX

tl-crowned. The Ps arc actually quite large, but not • proportion to the molars. The Pi is elongate along 'o oblique axis, whereas the smaller P2 is more ,*rr The broken LM1 was very tiny compared to 7 verv large and roundcdly square A12 and M 3 , hich arc not only long m/d but also very wide b/I. Tfic distal sides of the M3s arc broadly and shallowly arcuate and there is evidence, especially on the RM3, f a vcrv large cntoconid and a much smaller metaconid with a large mctast}'lid sandwiched between them. StW 53c. Glued fragment of R zygoma, plus adjacent maxilla. Does not match the small piece of zygoma preserved on the maxilla S t W 53b. It shows a more vertical descent of the inferior margin toward the tooth row. Is this a different individual? T h e maxillary sinus extended at least to the region of the zygomaticomaxillary suture. There arc laterally facing masseteric scars on the maxillary margin of the arch; the anterior margin probably rose quite steeply. In front of the scars is a small but well-defined and inferolatcrally facing maxillary tuberosity. The temporal fossa was probably conical, narrowing infcriorly. StW 53e. Multiple pieces of braincasc bone glued together, representing part of the occipital and parts of the parictals. The large anterior piece may not belong with the rest, since there is a strong medially curving temporal line on the middle piece that may not continue on to the front one. T h e anterior piece is flat and probably comes from the side wall. T h e middle piece has a strong temporal line externally, and internally has four meningeal grooves. T h e curvature of this piece, plus the position of the grooves, suggests that it is from the posterior part of the L parietal. The third piece is from the occipital bone. It preserves part of the weakly interdigitated L larnbdoid suture, and part of the nuchal plane with a strongly pointed, wedge-shaped and downwardly oriented external occipital protuberance. Into this flow strong but, as seen on the L, not very long nuchal lines. There is a shallow impression for the L occipital lobe, and part of a transverse sinus, suggesting that the occipital lobe was small. This region is also undercut by the steep nuchal plane. If these pieces do go together, this occipital piece should be placed lower down than on the reconstruction. Also, the external occipital protuberance is not in line with a sagittal suture.

325

StW 98. Mostly complete R petrosal, missing squamosal part, most of tube and tip of mastoid. A medium-sized bone, it was probably not very wide across the superior surface, which is perfectly flat with the faintest trace of a superior petrosal sinus. The subarcuatc fossa is fully closed over, but there is a well-incised sub-subarcuatc fossa. A single wellincised sigmoid sinus runs along the petrosal and may have clipped the corner of the parietal in the region of the shallow but right-angled parietal notch, which appears to have been inwardly sloping. Externally, the plane of bone above the well-developed supramastoid crest angles inward. This crest forms the superior margin of a thick muscle—scar band whose inferior margin occurs laterally down along the posterior and then lateral part of the mastoid process. The crest appears to run anteriorly into a pronounced supramcatal crest. T h e posterior surface of the mastoid process is very broad and bears a very large but poorly defined digastric fossa, at the bottom of which emerges part of a moderately deep, narrow and not very long a/p mastoid notch. T h e tip of the mastoid process was not very robust, but it cannot be seen how far downward it extended because of breakage that reveals some small air cells. Medial to the notch the bone rises toward the region of the occipitomastoid suture. Directly in line with the notch, but in front of the processes, lies a large stylomastoid foramen, anteromedial to which is a small, probably styloid, pit. Medial to that is the small and downwardly pointing carotid foramen. T h e tubular cctotympanic is broken; its walls are thick, and it probably did not extend fully laterally. StW 151. This fragment of the superior part of a R ramus is small, and the medial part of the condyle is especially badly broken. T h e bluntly pointed coronoid process is subcqual in height to the laterally uncxpanded condyle. T h e sigmoid notch crest is only moderately deep, with its greatest depth at the midpoint. The sigmoid notch crest runs to the lateral side of the condyle. T h e articular surface of the condyle is straight, the posterior surface below is slightly rounded, and there is little delineation of the neck. W h a t remains of the upper gonial region is inwardly deflected and somewhat rugose internally. A stout crest descends from the coronoid, thickening toward where it would have met the internal alveolar crest. Behind the thickest preserved part of the crest is the mandibular foramen, which opens upward and

SITE

326

slightly back. There is no lingula; rather, a bony defect interiorly. StW 252m. Fragment of the R frontal process of a maxilla. The maxillary sinus goes high up into the process, which has a very flat and minimally curved anterior surface. There is a sharp edge to the preserved superior part of the nasal aperture. There is no trace of a conchal crest on the preserved flat wall of the nasal cavity. Orienting on the thick frontomaxillary suture and the lacrimal groove, the lower face would have been fairly vertical and flat across the nasals. The lacrimal canal lies above the superior extent of the maxillary sinus, and is very long. StW 252n. This is a L frontal process extending from the frontomaxillary suture, but not as far infcriorly as S t W 252m. The anterior surface is flat, and the extent of the maxillary sinus makes it a good counterpart to S t W 252m. Putting the two pieces together suggests that the face was flat across the top of the nasal region. However, the flatness of S t W 252n is compatible only with difficulty with the roundedness of the nasal margin in S t W 252a. T h e lacrimal canal is long. StW 252o. Interorbital fragment with part of L orbit. Bone thin. The glabella region is angular in profile, with overhanging nasal roots, and is indented centrally as seen from above. Nasion rises very high. The nasal bones would have been broad superiorly, and the frontonasal suture was strongly arced from side to side. The frontal rises flatly behind the glabella, and the supraorbital margin is very thin s/i, with a strong angle out of the slightly concave orbital roof, and is indented medially by a distinct notch. The interorbital region is broad superiorly, but tapers inferiorly. Two or three air cells are visible centrally, but do not penetrate into the glabellar region. There is apparently no frontal sinus at all. T h e temporal line swings sharply back at midorbit, and emerges not far behind the orbital margin. There is a strong and long frontal crest that runs between the fronts of the orbital cones, which would have been raised significantly above the cribriform plate. The frontal lobes extended far forward over the orbital cones, and the posterior curve of the frontal crest is beginning to diverge from the more vertical exterior curve of the frontal. StW 252p. Relatively fragment.

thick-boned

braincasc

LNTUIES

StW252pb( = 257). Uninformative cranial fa StW 252qb ( = 258). Uninformative fragmc cranial bone.

°*

StW 252q ( = 252s + 258). Part of a L p a r i c reconstructed from multiple pieces. Thin-boned k adult, from a very small individual that had a f' 7 flat, broad and low braincasc. The specimen narro^ posteriorly, and bears small depressions inside. Parr r the sagittal suture is present, deeply denticulate; also part of the coronal suture, finely denticulated, part of the squamosal, low and virtually horizontal damaged but low lambdoid suture and part of the parietomastoid suture, strongly curved laterally. There is heavy sutural overlap. T h e anterior branch of the meningeal artery emerges near pterion and runs posteriorly instead of more parallel with the coronal suture. If there is a temporal line, it is only visible anteriorly, running close to and parallel with the sagittal suture. This parietal piece is very tiny and low, and was from a low, flat and short neurocranium

(hominid?). StW 252r ( = 253). Tiny fragment of R zygoma (1999), plus R parietal fragment (2001), possibly with part of sagittal suture. Not informative. StW 252s. Two Uninformative.

tiny

braincasc

fragments.

StW252sc(

= 254). Uninformative

StW252se(

+ 26S). Tiny mastoid fragment.

StW 252tb ( = 266b). Not present. StW 252tc ( = 256). Probably part of a temporal. Uninformative. StW 252td ( = 263). Part of R mastoid, highly pneumaticized. Sigmoid sinus very large and well defined; transverse sinus would not have crossed on to parietal. StW252u ( = 260). Various tiny cranial fragments. StW 252v ( = 262). Part plane is very low and wide, nuchal plane is very gentle. size. Docs not go with S t W is well defined.

of occipital. Occipital and the angle with the Very thick bone for its 252q. L transverse sinus

StW 498c. Fragment of ramus.

STEUKKONTEIN

327

St\V498g. Fragment of cranial vault, with possibly unmatched pieces front and back. Temporal lines are wavy, but there is no crest.

Clarke, R.J. 1999. Discovery of complete arm and hand of the 3.3 million-year-old Australopithecus from Sterkfontein. S.Afr.J. Sci. 95: 477-480.

St\V498r (formerly 499). Very large petrosal with a large arcuate eminence far from the margin, a small subarcuate pit, and a sulcus below. T h e tubular ectotvmpanic is thin-walled and bears a vaginal process that is posteriorly placed and runs far laterally and may have contacted the mastoid. There is also a faint trace of a superior petrous sinus. Differs from StW53gandStW252ta.

Conroy, G. C. et al. 1998. Endocranial capacity in an early hominid cranium from Sterkfontein, South Africa, Science 280:1730-1731.

REFERENCES Broom, R. 1936a. A new fossil anthropoid skull from South Africa. Nature 138:486-488. Broom, R. 1936b. The dentition of Australopithecus. Nature 138:719. Broom, R. 1937. The Sterkfontein ape. Nature 139:326. Broom, R. 1947a. Discovery of a new skull of the South African Ape-man, Plesianthropus. Nature 159: 672.

Conroy, G. C. et al. 2000. Endocranial capacity in Sts 71 {Australopithecus africanus) by three-dimensional computed tomography. Anat. Rec. 258:391-396. Cooke, H. B. S. 1994. Phacochoerus modestus from Sterkfontein Member5. S.Afr.J. Sci. 90: 99-100. Gregory, W. K. and M. Hellman. 1939. The dentition of the extinct South African man-ape Australopithecus {Plesianthropus) transvaalensis Broom. A comparative and phylogenetic study. Ann. TransvaalMus. 19:339-373. Holloway , R. L. 2000. Brain. In: E. Delson (ed.), Encyclopedia of Human Evolution and Prehistory. New York: Garland Press, pp. 141-149. Hughes, A. R. and P. V. Tobias. 1977. A fossil skull probably of the genus Homo from Sterkfontein, Transvaal. Nature 265:310-312.

Jones, D. I., A. Brock and P. L. McFadden. 1986. Palacomagnetic results from the Kromdraai and Sterkfontein hominid sites. S.Afr.J. Sci. 82:160-163. Broom, R. 1947b. Further remains of the Sterkfontein Ape-man, Plesianthropus. Nature 160:430-431. Kuman, K. 1994. The archaeology of Sterkfontein—past and present./. Hum. Evol. 27:471-495. Broom, R. and G. W. H. Schepers. 1946. The South African fossil Ape-Men, the Australopithecinae. TransKuman, K. 1996. The Oldowan industry from Sterkvaal Mm. Mem. 2:7-153. fontein: raw materials and core forms. In: G. Pwiti and R. Soper (eds.), Aspects of African Archaeology\ Papersfromthe Clark, W. E. Le Gros. 1967. Man-Apes or Ape-Men? New 10th Congress of the Panafrican Association for Prehistory York: Holt, Rinehart and Winston. and Related Studies. Harare:, Zimbabwe. University of Clarke, R. J. 1988. A new Australopithecus cranium from Zimbabwe Press, pp. 139-146. Sterkfontein and its bearing on the ancestry of ParantbroKuman, K. and R.J. Clarke. 2000. Stratigraphy, artefact inpus. In: F. E. Grine (ed.), Evolutionary History of the dustries and hominid associations for Sterkfontein, Mem"Robust" Australopithecines. New York: Aldine de Gruyter, ber S.J Hum. Evol. 38: 827-847. pp. 285-292. Mayr, E. 1950. Taxonomic categories in fossil hominids. Clarke, R. J. 1990. Observations on some restored hominid Cold Spring Harbor Symp. Quant. Biol. 15:109-118. specimens in the Transvaal Museum, Pretoria. In: From Apes to Angels: Essays in Anthropology in Honor of Phillip V. McKee, J. K.J. F.Thackeray and L. R. Berger. 1995. Faunal assemblage seriation of South African Pliocene and Tobias. New York: Alan R. Liss, pp. 135-151. Pleistocene fossil deposits. Am. J. Phys. Anthropol. 96: Clarke, R. J. 1994. On some new interpretations of Sterk235-250. fontein stratigraphy. S.Afr.J. Sci. 90:211-214. Partridge, T. C. 1978. Re-appraisal of lithostratigraphy of Clarke, R. J. 1995. Mr, Mrs and Miss: Conceptions in studSterkfontein hominid site. Nature 275:282-287. ies of human ancestry. In: J. Gibert (cd.), Hominids and Their Environment during the Lower and Middle Pleistocene Partridge, T. C. 1982. The chronological positions of the of Eurasia: Proceedings of the International Conference of hominids of southern Africa. Congres International de PationtologteHumaine, ler Congres>Tomc 2. Nice: CNRS, Human Palaeontology. Orce, Spain: Museo de Prchistoria, pp. 617-675. pp. 327-329. Partridge, T. C. et al. 1999. The new hominid skeleton from Clarke, R. J. 1998. First ever discovery of a wcll-prcscrvcd Sterkfontein, South Africa: age and preliminary assessskull and associated skeleton of Australopithecus. S. Afr. J. ment./ Quatern. Sci. 14:293-298. Sci. 94:460-463.

328

S I V K \\ N f U I K vS

Partridge. T C* ct al. 200X Lower Pliocene hommu! re* radius trom Stcrkfontein. «SWVtf*r 300: (>07-(>l2. Robinson, J. T 1954. Hie genera and species of the Aus* tralopithcciiuc.-•/«./ Ptyi Jnthvpel \2: 181-200. Robinson, J. T. 1972. £Wv ffcmimJ /Wnnriirt./ L<\v#icfiort. Chicago; Lhiivtrsitv of Chicago IVcss. Robinson. J. T and R.J. Mason. 1957. Occurrence of stone artefacts with ,iu>frt;/cNtfwus at Steikfontein (Parts I and 2). Aw/*** ISO: 521-524. Schuarc7.lL P., R. Gnin and P. V. Tobias. 1994. ESR dating o\ the australopithccinc site of Steikfontein, South Africa./ //*w. /;«W. 2o: 175-181. \rrba. E. S. 1982. Biostratigraphy and chronology, based particularly on Bovidae, ot southern honiinid-associated assemblages: Makapansg.it, Stcrkfontein, Taung, Kromdraai, Swartkrans; also IClandsfontcin (Saldanha), Broken

STI-:KKI*ONTKIN

Hilt (now Kahwe). and Cave of Hearths C W * / /V.v,,<%,V Humane, la C W ^ T llw7%!*' c2 N CNUS. PP. 707-752. ' »<* ftct tiwUt

c

Ytha. K. S. 1985. Karly hotninids in southern After dated observations on chronological and eeoWie ill! T ground. In: P. V. Tobias (ed.). //*»,,«£/ / \ ^ / M . , ?I /Vww/ .!«./ /*,/«,* New York: Alan R 1 ; ' ' l s 195-200. IT-

Repository Transvaal Museum (Northern Flagship Institution) | \ ) Box 43, Pretoria 0001, Gautcng, South Africa (TM .uul Sis catalog number); Department of Anatoiuv .uul Ibnvui Biology, University o( the Witwatersrand Medical School, York Road, Parktown, Johanncsbutg 2193, South Africa (St\V catalog numbers).

Figure 1. Sts 1, palate (scale — 1 cm),

STERKFONTEIN

PONTEIN STERKFONI

Figure 2. Sts 5, cranium (scales = 1 cm; close-up not to scale).

329

330

SITE

STERKFONTEIN

k

ENTRIES

Figure 2.

(Continued).

STBRKFONTEIN

STERKFONTEIN

Figure 3. Sts 7, partial mandible (scales = 1 cm).

331

&ITB

332

EWTRIE*

^H

1

l i J-^

1

H1

' ^r

'£

•|j| 1

|Kjj|g jtf

^H^^^| -

*•'¥h%&

Figure 4. Sts 8, upper molars (scale =

1 cm).

STERKFONTEIN

' '•

"

J

'

"••

I

''-.".-w\

.''T^?! -

STERKFONTEIN

1 •

- -1

Figure 5. L: Sts 9, R: Sts 55b, lower molars (scale = 1 cm). STERKFONTEIN

Figure 6. Sts 10, close-up pf upper molar (scale = 1 cm).

STERRFOXTEIX

STERKFONTEIN

J

•

Figure 7. Sts 19, baskranium (scale = 1 cm).

1

^^

T ^^^

L*J1 I ; •L

-

• t^Jfc^f

STERKFONTEIN

-iiafl

Figure 8. Upper molars. L: Sts 22, R: Sts 32 (scale - 1 cm).

333

SITE

334

STERKFONTEIN

ENTRIES

Figure 9. Sts 24, partial mandible (scale =! 1 cm).

335

STERKFONTEIN

w^W&$ik

':•.• : .-' :' '•-•' 1

STERKFONTEIN

*'&** •*&*&.

'

1 -": •"- *f}——'" j ..;;-~,iV H

Figure 10. Sts 24a, isolated teeth and partial R and L maxillae (scale = 1 cm).

SITE ENTRIES

336

STERKFONTEIN

Figure 11. Sts 28, upper molars (scale = 1 cm).

STERKFONTEIN

Figure 12. Sts 35, upper teeth (scale = 1 cm).

337

STERKFOXTEIN

I

^^^^^^/^^^5H

^ ; « ^BP» j ^ l L ^ J

K v v,-.. a

W^*', / ifl H

^T X>i ftjl

VH

Kj

K

**# 1

HS>\ *J

P 'l£y»fl • >iv^^i

(

^^L

HvTyf L/*^k£^^l

i$rl ^fc«

STEBKFONTEIN

Li

'•*

fl

' «H ^H

^H

ftL^J

I^^H

•

4

Figure 13, Sts 36, incomplete mandible (scales = 1 cm).

HP

\Jm

338

S l T C ENTRIES

STERKFONTEIN

STERKFONTEIN

Figure 14. Sts 37, upper molars (not to scale).

Figure 15. Sts 52a, partial lower face, and Sts 52b, partial mandible (scales g 1 cm).

STERKFONTEIN

STERKFONTEIN

Figure 15. (Continued).

339

340

SITE

STERKFONTEIN

ENTRIES

Figure 15. (Continued).

STERKFONTEIN

STERKFONTEIN

Figure 16. Sts 53, palate (scales = 1 cm).

341

S«YK

U2

EvMtmeas

* ;*VH

t

f £ *t

STERKFONTEIN

.#

Figure 17. Sts 57, upper molar (scale = 1 cm).

STKRKFONTEIN

STERKFONTEIN

Figure 18. Sts 71, partial cranium (scales = 1 cm; close-up of nasal cavity not to scale).

343

344

SITE

STERKFONTEIN

ENTRIES

Figure 18.

(Continued).

STERKFONTEIN

STERKFONTEIN

Figure 19. StW 13, partial cranium (scales - 1 cm).

345

346

SITE ENTRIES

STERKFONTEIN

Figure 19. {Continued).

7

STERKFONTEIN

STERKFONTEIN

Figure 19. {Continued).

347

348

SIM-: E N T R I E S

STERKFONTEIN

Figure 20, StW 53g> petrosal (scales = 1 cm).

STERKFONTEtN

STERKFONTEIN

Figure 21. StW 73, partial maxilla (scales - 1 cm).

349

350

SITE ENTRIES

STERKFONTEIN

Figure 22. Unerupted permanent teeth, from L to R: StW 75,76,77,78 (scale = 1 cm).

STERKFONTEIN

Figure 23. StW 104, juvenile L partial mandibular corpus (scales = 1 cm).

STERKFOXTEIX

STERKFONTEIN

351

Figure 24. StW 151, isolated teeth and mandibular and maxillary fragments (scales == 1 cm).

352

SITE

STERJCFONTEIN

ENTRIES

Figure 24. {Continued).

353

STERKFONTEIN

i

1 1 1 ' 1• ' i - 1 ' '.' '

H F ^ v ^ ^^^HB «:_ •«•> S

^R'vSffli 1

1 •"(>:;'; ^ -' ^?

|

t •'

- - ' - 1

f ,;'"i'i''.

I '9 1 1

Bj

' BB^''£^5?^^PI

Wftfr

° '• ' •

WE&

; •

' 1 U fe$^11 •(£-''#•' ^ii^fe 9l7 r ^ S ^ ^ ^ l ^^^Hs I : jjfaZ- ^i^ ^ ^ • ti§p$s>'• K Jiw^ [•&§H&&¥ •H**v y- . "-rr.:fEgK3&£jfl 1 '-"-"-'."Jj-|H

• K T A 3 B W ^ - *-^ iFiF*J

; s i W y . L ^w*5i».. "'

-« Jfti

l|H

;

far- "• JQjSa

.JvSi '

Vflfl

^ ^ y ^ ^ ^ U I I H

V

;

% | M E S | I flmUH

•

l^ll'iiaWil

LTJBIHL''

WBrfljjfi <\y A " " f r IT ' lEv'T^B

1 ilillf'Vifc 1 i l l

M n ?

9

K ^ j b d

BH9(• ^ 1

K3&jf$i»• l W ^ r a fM• ^^I W H^ r l ^ >;«

•BM|M

• •

Tmyk 1

RR^tM H i *

' - •

•

7 l « I B

MEi&LiSi STERKFONTEIN

Figure 25. StW 183a, various facial and maxillary elements (scales = 1 cm).

;^4um National d'HIstoIre Naturell u*fiartement de Pr6htetoire 4

m a ? i w - r \ « D-~n K A I T I

354

SITE

STERKFONTEIN

ENTRIES

Figure 25. (Continued).

STERKFONTEIN

STERKFONTEIN

STERKFONTEIN

Figure 25. {Continued).

Figure 26. StW 185, region of foramen magnum (scales = 1 cm).

355

356

SITE

STERKFONTEIN

k

ENTRIES

Figure 27. StW 252a, L anterior palatal region (scales = 1 cm).

STERKFONTEIN

STERKFONTEIN

Figure 27. {Continued).

357

358

b

SITE ENTRIES

STERKFONTEIN

Figure 28. StW 252c, R maxillary fragment (scales I 1 cm).

STERKFONTEIN

STERKFONTEIN

Figure 29. StW 252g and h, upper molars (scale = 1 cm).

STERKFONTEIN

Figure 30. Stw 252i-l, upper L P 2 - M 3 (scale = 1 cm).

359

360

STEHKPON™

SITE ENTRIES

Figured Land Center: StW252o,frontalS

;

R: StW 252sa,R petrosal (scales = 1 en).

STERKFONTEIN

STERKFONTEIN

Figure 32. StW 252q, parietal and occipital fragments (scales = 1 cm).

361

SITE ENTRIES

362

STERKFONTEIN

Figure 33. L: StW 277, upper molar, R: StW 278, lower mokr (scale = 1

STERKFONTEJN

Figure 34. StW 283, upper L molars (scale m 1 cm).

STERXFOKTEIK

STERKFONTEIN

Figure 35. StW 327, partial L mandibular corpus (scales -

363

k

364

SITE

STERKFONTEIN

ENTRIES

Figure 36. StW 384, partial R mandibular corpus (scales = 1 cm).

STERKFONTEIN

STERKFONTEIN

Figure 37. StW 404, partial mandible (scale il 1 cm).

365

SITE

366

STERKFONTEIN

ENTRIES

Figure 38. StW 498a and b, L and R maxillary fragments (scales = 1 cm).

STERKFOXTEIX

STERKFONTEIN

Figure 38. (Continued).

367

368

S I T E EKTRBES

STERKFONTEIN

Figure 3& {Contmued)^

STEIIKFONTEIN

369

BRrcf>

-TIB

H ' tiff''

1

1

I

1

fc\a•*"

Fr<|&l^yifc#

ft

»Cfg«>«

I'»-J' a

Ma %,«B

vV^ V 1 ^ay 1

I w

^^B

^ ^j^^r

1

I^H

^N^H& • wFsw ^ S |

^KTrAjV, 9

STERKFor>frEiN Figure 39. StW 498ct L and R mandibular elements, and StW 498f, parietal fragments (scales - 1 cm).

370

SITE ENTRIES

STERKFONTEIN

Figure 39- {Continued).

r

$ 3" IE isiKFtosrrCIS

N

STERKFONTEIN

Figure 40. StW 499, L petrosal (scales - 1 cm). figure

3*1

372

SITE ENTRIES

STERKFONTEJN

Figure 41. StW 505, partial cranium (scales = 1 cm; close-up not to scale).

STERKFONTBIN

STERKFONTEIN

Figure 41. {Continued).

373

SWARTKRANS

LOCATION Solution-cavity breccia-fill site some 10 km NW of Krugcrsdorp, Gautcng Province, South Africa (Map 4). Approx. 2 km from Stcrkfontein. DISCOVERY R. Broom, J. T. Robinson and co-workers, November 1948-51; J. T. Robinson, 1951-52 (with continuing involvement to 1960); C. K. Brain, 1966-86 (with continuing involvement to 1990 and beyond).

MATERIAL Since 1948 over 300 hominid fossils (including many isolated teeth) have been recovered from Swartkrans. Most of them have been attributed to Parantbropm, but several dozen have been allocated to the genus Homo. Among the best-known Parantbropm fossils from Swartkrans are the crania SK 46 and 48, and the mandibles SK 6 (the adolescent holotypc of Parantbropm crassidens), 23 and 34. Notable specimens attributed to Homo include the SK 847 partial cranium (includes SK 80 and 846b) and the SK 15 mandible, holotypc of Tclantbropus capensis.

DATING AND STRATIGRAPHIC CONTEXT As with all sites of similar formation, the filled solution cavity at Swartkrans presents a complicated history of infill and collapse. The site was initially discovered by lime miners, and mining activities, mainly

involving blasting, disrupted the early years of fossil exploration (though they also produced important hominid fossils, including the SK 48 cranium and SK 23 mandible). However, thanks largely to the efforts of Bob Brain, the complex geological history of Swartkrans is now well understood and has been summarized most recently by Brain (1993). In 1958 Brain showed that there were two unconformably related masses of breccia at Swartkrans: the Pink Breccia, occupying the space known as the Outer Cave; and the Stratified Brown Breccia, which partly filled the Inner Cave. However, as excavation progressed it became clear that matters were more complex, and that the Outer Cave, at least, contained breccias accumulated at different periods. Further, it was found that the Pink Breccia, which at that time had produced all the hominids, formed an isolated "Hanging Remnant," stuck to the north wall of the cave and undercut by an erosional surface. In 1976 Butzer formally divided the Swartkrans Formation into Members 1 (the Pink Breccia and related deposits) and 2 (the Stratified Brown Breccia of the Inner Cave plus other breccias in the Outer Cave). Eventually this scheme was further refined with the recognition of five members in total, and of a counterpart deposit to the Hanging Remnant that was termed the "Lower Bank" and was included as a subunit of Member 1. Ultimately it was realized (Brain, 1993) that, faunally, Members 1, 2 and 3 do not differ greatly, and are thus not far apart in age. Parantbropm remains have by now been found in all

374

SWAUTKUANS

0( these units, but mainly in the Hanging L | l i n ; i n t of Member 1; by Member 3 times they are • r i r c . The age of Swartkrans Members 1-3 has fir resisted geochronometric determination, but \ c j r combined span is estimated faunally to lie between about l.S and 1.5 Ma (or even younger), with the three members lying in chronological sequence (Vrba, 1982; Brain, 1993; McKec, Thackeray and Bcrccr, 1995; Grinc, 2000). Putative Homo fossils come from Members 1 and 2, with the Telanthropus mandible (SK 15) a »d t n c Plirt*;u< cranium SK 847 both from Member 2. Member 4 is rich in Middle Stone Age artifacts, but has yet to produce fossils. Member 5 is a subreccnt deposit dominated by springbok bones.

ARCHAEOLOGICAL CONTEXT The Member 1 Hanging Remnant has produced few lithics, but in contrast Mode 1 stone tools are quite abundant in the Member 1 Lower Bank, which has also yielded fractured bones that were evidently used as tools and whose tapering tips have been polished smooth. Such bone tools, believed to have been used as digging implements, are found throughout M e m bers 1-3 (see Brain and Shipman, 1993). Stone artifact assemblages from Members 1 - 3 are all of Oldowan aspect and are similar throughout, although there are hints of biface technology in Members 2 and 3 (Clark, 1993). Brain and Sillen (1988) reported evidence that some Member 3 bones had been heated to temperatures typical of campfires, and thus suggested that fire had been used by Member 3 hominids. There is no definitive way to associate either the stone or the bone tools with any particular kind of hominid, though Susman (e.g., 1989) has argued on both anatomical and probabilistic grounds that Paranthropus was a toolmakcr.

PREVIOUS DESCRIPTIONS AND ANALYSES Hard on the heels of beginning work at Swartkrans broom (1949) reported finding there a partial h o minid mandible (SK 6) that he provisionally allocated to the new species Paranthropus crassidens. New fossils of similar aspect, duly referred to the new species (Broom and Robinson, 1949a), followed in quick succession and were accompanied by fossils belonging to a different and less megadont hominid. One ot these, the SK 15 mandible, was made the holotypc o r the new genus and species Telanthropus capensis (Broom

375

and Robinson, 1949b). In these authors' initial view the new species recalled "Heidelberg man," though in the following year they were less specific in their comparisons (Broom and Robinson, 1950a). In the latter year Broom and Robinson (1950b) were also able to report an impressive array of P. crassidensfinds,including the large SK 12 mandible. In April 1951 Broom died, leaving John Robinson to undertake fuller interpretation of the materials they had jointly excavated at Swartkrans and Stcrkfontcin. In 1953 Robinson published a long paper on Telanthropus in which he described several new Swartkrans fossils representing this form, and corrected the earlier impression that the Telanthropus remains were from a later period than those yielding Paranthropus at Swartkrans. He affirmed the distinctiveness of the two forms, and that his Telanthropus was more similar to Plesianthropus (from Sterkfontein) than to Paranthropus. Nonetheless, in his view Telanthropus was "a distinct advance over the known australopithecincs in the direction of the cuhominids" (Robinson, 1953: 486). Shortly after this, Robinson (1954) reviewed all of the South African australopiths then known, sinking Broom's genus Plesianthropus (and also synonymizing "Meganthropus* with Paranthropus). Within the subfamily Australopithecinae of the family Hominidae, he recognized two genera. Australopithecus contained a single species, A. africanus, with two subspecies, A. a. africanus (Taung) and A. a. transvaale?isis (Sterkfontein and Makapansgat, plus unspecified East African material). Paranthropus contained one South African species, P. robustus, divided into two subspecies, P. r. robustus (Kromdraai) and P. r. crassidens (Swartkrans). In addition, he invoked the species Paranthropus palaeojavanicus to accommodate the "Megantbropus" material from Java. T h e hominine T. capensis he placed in a phylogenetic trichotomy with P. robustus and A. africanus, noting that Plesianthropus possessed various specializations that excluded it from Telanthropus ancestry. Robinson contrasted this scheme with the ultralinear one proposed by the "determined lumper" Mavr (1950), but alas it was something closer to Mavrs scheme that was to win out as the Evolutionary Synthesis swept all before ii during the 1950s. For by the end of the decade ever Robinson himself (Robinson, 1961)—who by that time had completed an extensive summary of the by thcr extensive evidence from all the South African australopith sites (Robinson, 1956)—was to sink Telantbropti

376

SITE

into Homo, though he remained in the small minority that maintained the generic distinction between Parantbropus and Australopithecus. By this point it had also become conventional to deny specific distinction between Kromdraai and Swartkrans Parantbropus (see historical survey by Le Gros Clark, 1967). In the two decades of continuous excavation under the supervision of Bob Brain, the Swartkrans site produced a continuing stream of hominid fossils. These have been described by such authors as Brain et al. (1970); Day and Schcuer (1973); Brain, Vrba and Robinson (1974); White (1976); Clarke (1977,1990); Susman (1989); Grine (1988, 1989, 1993); and Susman, dc Ruiter and Brain (2001). To summarize, it is now generally agreed that two hominid genera are present at Swartkrans. Opinions are still divided over whether the "robust" form should be allocated to the genus Australopithecus or to the genus Parantbropus, although sentiment at this site, as elsewhere, is moving significantly toward the latter (e.g., Clarke, 1996). During the 1960s and 1970s it was conventional to place the Kromdraai and Swartkrans "robust" populations in the same species, Parantbropus robustus. However, Howell (1978) resuscitated the issue of whether a species distinction should in fact be made, and there is currently a groundswell of support for the notion that a species Parantbropus crassidens should be recognized at Swartkrans in addition to Parantbropus robustus at Kromdraai (see, e.g., Grine, 1981). In the case of the other genus, the one containing the SK 15 "Telanthropus" mandible and its like, it is generally agreed today to be Homo, though species attribution is uncertain. Grine (2000: 682) has bravely suggested that the Swartkrans Homo is "probably cf. Homo habilis in Member 1 and cf. Homo erectus in Member 2," but this question has yet to be resolved to general satisfaction, and is in any event beyond the scope of the descriptive portion of this volume. Holloway (2000) reports an endocranial volume of 530 ml for the "robust" natural endocast SK 1585. None of the crania is well enough preserved for direct determination.

MORPHOLOGY

Since there is only one possible association at this site among specimens with both upper and lower teeth (SK 12 contains both a lower face and a mandible, but the former lacks teeth), separate upper and lower dental morphs are identified below, as well as separate

ENTRIES

facial morphs. The exception is SK 55, since it Scc reasonable to conclude that the two specimens b "* ing this number belong to the same individual. SK 48 Upper Dental Morph (includes SK 11 12 13 46,47,49,52,65,67,79,83 and SKWll) ' ' ' In general, the upper dentitions described in the following paragraphs arc similar enough, allowing f0r variation, to be discussed together. Specimens with missing, very worn and/or cracked teeth are included in this morph if the teeth conform to basic tooth proportions and shape as well as relative tooth size, and there is also some relevant detail preserved. The assignment of such specimens to this group was also in some cases potentially corroborated by their similarity to specimens with more visible dental morphology, and their inclusion seems to warrant the recognition of two cranial/palatal morphs within the same broad dental grouping. One such morph is characterized by s/i thin supraorbital margins with somewhat delineated superior edges, relatively flat and somewhat/very deep faces, thin and blunt lateral nasal crests along the entire side of the nasal aperture, infraorbital foramina that lie well inferior to the inferior orbital margin and do not have gutters descending from them, and palates that are straight or only slightly curved across their fronts. Included in this morph are SK 11, SK 12, SK13,SK48,andSK49. The second morph is characterized by smoothly rounded supraorbital tori (as seen in profile); inferiorly somewhat broad nasal apertures with the gently concave nasoalveolar clivus slung (hammocked) below between flat, a/p broad facial "pillars" that extend up from the 1 2 - C alveolar crests but do not go superiorly beyond the infraorbital foramen; palates that are tightly curved across the front, and a/p long and somewhat divergent tooth rows. Included here are SK 46, SK 47, SK 52, SK 65, possibly SK 83, and SKWll. SK 11. Partially reconstructed upper jaw with highly worn, broken and/or cracked cheek teeth. Nasal aperture is broad interiorly, with blunt lateral margins and rounded inferior corners. The lateral sides of the nasal aperture are bounded by pillar-like structures that fade out below toward the C alveolar region. On the R the pillar is delineated laterally by a sulcus. The floor of the nasal cavity flows smoothly onto a relatively long and downwardly curving

SWARTKRANS


377

originates above M l and runs sharply up and out. The incisive fossae also lie quite far within the nasal cavity, and face backward, so the canal between them and the incisive foramen must be very obliquely oriented. The palate is broad across the front, but it was not originally very long and is quite narrow internally. There is a fairly large single incisive foramen, lying just behind the incisors. There is a low midline keel. Internally on both sides the maxillary sinus extends throughout the preserved maxillary and zygomatic region, and is incompletely subdivided by low bony septa. Also preserved on both sides is the bony tube for the infraorbital nerve. This is fairly vertical, suggesting that the infraorbital groove in the floor of the orbit would have run almost as far forward as the infraorbital margin. O n both sides, and separated from the maxillary sinus, is a long lacrimal groove that would have been covered by bone to some extent. As seen on the L, a low, short conchal crest is preserved just in front of the lacrimal groove and low down, close to the floor of the nasal cavity. The inferior nasal concha would thus have been situated far back in the nasal cavity. The alveoli for the anterior teeth are large, and lie straight across the front of the maxilla. Those for the l i s are not much larger than those for the laterals; the C alveoli are huge and long, and oriented only slighdy obliquely. The crowns of all anterior teeth would have been large. P I would have been slightly shorter m/d than P2, but both were apparendy as wide b/1 as M l . As seen on both sides, the P i s and P2s have three roots. M 2 is shorter m/d than M l . SK 13/14. Maxilla with cheek teeth (SK 13) with additional L M 2 (SK 14), and M3s erupting if reconstruction is correct. A crushed nasal aperture is preserved; it would not originally have been very wide, and the floor of the cavity flows smoothly out onto the clivus. The clivus, which is very gently curved across, is slightly sunken below the level of the low pillars that define it on either side, rising from the alveolar region at the canine and Aiding out by the level of the inferior border of the nasal aperture. It appears to have a double gutter forming the inferior margin of the nasal aperture. Downwardly facing infraorbital foramina are situated well below the inferior orbital border and well lateral to the tops of the pillars. Shallow grooves descend from the foramina. As seen on both sides, the infraorbital plane above the foramina is flat. On the R

378

SITE

the frontal process apparently projected forward slightly. Both infraorbital planes face forward, but are not quite vertical. The anterior root of the zygomatic arch takes origin above P2, and very close to the groove descending from the infraorbital foramen. T h e palate is moderately long and broad and somewhat divergent posteriorly. It is very shallow anteriorly, and deepens somewhat posteriorly. T h e moderate incisive foramen is level with the P i s and close to the l i s . The upper I alveoli are small, the l i s slightly larger than the I2s.The C alveoli are somewhat larger but would not have housed large roots. Even though P I is smaller m/d and b/1 than the P2, both appear quite large relative to the space of the anterior teeth and the size of M l . P 1 - P 2 were probably occlusally wrinkled. They are similar in being generally bulbous, especially on the lingual surfaces, with large and internally placed protocones that lie slightly mesial to the smaller and more centrally and peripherally placed paracone. Stout preprotocristae terminate on the mesial side of the paracone in a distinct parastyle-like swelling. The slender postprotocristae are shorter b/1 and terminate on the side of the paracone. T h e horizontal groove between the protocone and the paracone is deeply incised. P I has two buccal roots; the molar roots go straight down and do not flare. The M i s are somewhat worn. T h e R and probably L M 1 had a distinct and relatively large protostvle and a buccal pit between the paracone and slightly smaller and buccally slightly and roundedly truncated metacone. A large protostylar swelling is seen on the RM2, but not on the L. Both M i s have very tall but not very m/d expanded hypocones that are delineated from a hugely thick postprotocrista. O n M 2 this crest and the metacone region are confluent, and this likely was also the case on M l . Also on M 2 , as better seen on the R, the preprotocrista is very thick as it leaves the protocone and tapers as it runs alongside the very large paracone to terminate before fully reaching the buccal side; thus the protocristae essentially completely envelop the paracone on its sides and also truncate its base internally This also appears to have been the configuration on M l . On the less worn and bener preserved RM2, there are deep grooves between the m/d long and somewhat b/1 wide hypocone and the postprotocrista; a deep groove is incised around the base of the paracone, separating it from the protocristae, and there is also evidence of deep enamel wrinkling. There is more than a hint of preserved morphology on the R M l , indicating that this tooth

ENTRIES

was similar to the M 2 in these details. The postcingula on the M2s are shorter b/1 than those on the M i s , whose hypocones are less long m/d but relatively wider b/1 and thus appear more m/d compressed. The M 2 s are tall-crowned, with sparsely but deeply creased surfaces. M3s are similar in overall shape to M2s, with expanded hypocones and more diminished metacones. Both are highly cuspulated, which obliterates normal morphology. T h e M s increase in size from M l to M 3 . SK 46. Somewhat crushed partial cranium with most of L side and more or less entire palate, lackin? anterior teeth, plus a handful of isolated fragments. Crushing has deflected the face and braincase away from one another, and has cracked and pushed the ethmoid and vomer into the midline. T h e teeth are highly worn. R P l and R and L P 2 - M 3 are preserved. Alveoli for remaining teeth are also present. T h e bone of the skull vault is not very thick, and the vault is lightly built compared to the face, despite the sagittal crest at its top. T h e braincase is quite long, and the face was originally quite deep. The frontal receded fairly sharply into a rather flat sagittal profile. T h e glabellar region is missing, as is the medial orbital wall of the remaining L orbit. T h e preserved supraorbital region is generally thin s/i but appears to thicken medially. There is a long, gently sloping posttoral plane that becomes sunken more medially into a "frontal trigone." T h e roof of the orbit is mildlv concave and curves quite sharply into the orbital margin above, but the "torus" itself is smoothly rounded in profile. T h e broken brow ridge reveals a capacious sinus that penetrates laterally at least as far as the thickened region of the brow, and extends posteriorly quite far into the posttoral plane. A low but thick temporal line emerges from high up behind the orbit, then fades out as it runs toward the sagittal crest. The crest is broken, so its original height is hard to determine, but it rises quite far anteriorly, right behind the trigone, and is of relatively uniform thickness throughout its preserved length. It probably divided posterior to the preserved portion. The orbit was probably taller originally than it is now, and its lateral margin more rounded. The rather bulbous zygoma probably faced forward, but was probably oriented more vertically than now. The middle part of the zygomatic arch is damaged and distorted, but this structure appears to have been tall s/i and relatively thick from side to side. T h e masseter

379

SWARTKRANS

he on the inferior surface. The thickness or the srar -arries forward into the maxilla. The anterior irch *~rhr inferior margin of the zvpomatic arch takes - i aS^e PI and, when viewed trom the front, ani~\ ^uicc steerlv upward. The ethmoids and other b 'i loisal structures have been crushed into the space 1 - j , c niixillan* sinus, so it is not possible to tell how larse this vacuity was. The nasoalveolar ciivus is not very long. It slopes n r j v forward below the ill-derined inferior nasal marrin. At the level of the alveolar margin the ciivus U ouire straight across, the surface above being a bit «calk>ned bv the anterior tooth roots. As preserved on the L. continuing from the region above the C, the bulkv bone tapers a bit upwards to form a thickly rounded lateral nasal margin. The C root occupies onlv a small proportion of this bony swelling below. On the L, the lateral portion of the nasal cavity arcs
doubled supnimastoid scar above. T h e sharp, more ridselike supramearal crest rakes origin above the scar rather than being confluent with it. The palate is relatively long and broad, and is straight across the front. T h e cheek tooth rows are straight and slighdv divergent posteriorly. T h e sides are steep, and the palate deepens markedly posteriorly from a verv shallow postincisol region. T h e relatively large incisive foramen lies level with the P i s , and widens forward. There is a slight midline ridge along the palate. Internally the petrosal was broad but not very tall. Its superior surface bears a ridgelike eminence above the superior semicircular canal. There is no subarcuate fossa, but a shallow sub-subarcuate fossa is present. A small sigmoid sinus curves down behind the petrosal, with only a hint of a superior petrous sinus. The Cs are obliquelv set in the jaw, and form the corners of the dental arcade. T h e roots of the l i s appear to have been bulkier and longer than those of the I2s. T h e C roots are larger than those of the Is, but these would not have been very large teeth. P i is slightly smaller overall than P2, which is wider b/1 than the M l . Both Ps are quite broad b/1 and rather narrow m/d, with verv rounded lingual surfaces. As seen on the L, P2 has two buccal roots. Even with extensive interstitial wear, it seems clear that the molars had increased in m/d length from M l to A15, with the distal part of M 5 swelled out by a thick postcingulum emanating from a relatively large hypocone that is buccal to the lingual side of the protocone. All three M s have large hypocone regions, which on M 1 - M 2 are situated directly lingual to the metaconc, and it also appears that the protocone becomes significantly larger from M l to M 5 , whereas the metaconc, which is somewhat smaller than the paraconc, does not change much. Both M5s preserve a stout but short and somewhat beaded postcingulum. SK47. Smallish subadult cranium, crushed flat s/i, with base preserved, plus partial palate with R M 1 - M 2 , P2 and M 5 erupting, LM2 and part of LM1. The nasoalveolar ciivus is partially preserved, and seems to have been quite short and to have flowed smoothly out of the nasal cavity, with no distinctive inferior margin. The R inferior corner of the aperture seems to have been smoothlv rounded. There is a small swelling in the region of the anterior nasal spines, and the incisive fossae lie right behind this.

**:.'

3S0

SITE

O n the L the medial part of the articular fossa is presenr, it is deep, with a very sloping posterior surface and a slightly less sloping anterior surface. The fossa is bounded medially by a moderate medial articular tubercle that contains the small foramen spinosum on its medial aspect. A low vaginal process runs along the posterior side of the ectotympanic, which is apprcssed to the mastoid region. The carotid foramina are small and downwardly pointed, and as preserved on the R, the jugular foramen is small and pointed forward. The L jugular foramen is larger. The foramen ovale lies well within the sphenoid, anteromedial to the foramen spinosum. T h e lateral pterygoid plate, preserved on the L, is quite large. The R mastoid process is preserved, the L partially. Both are filled with moderate-sized air cells. The supramastoid region of both is swollen laterally; each preserves a low, pointed tip and a broad, flat posterior surface. Just medial to the tip is a thin, moderately deep mastoid notch, medial to which the bone swells broadly, encompassing the occipitomastoid suture. O n the R, medial to the occipitomastoid suture, is a short Waldever's crest. There is a small but distinct occipital crest that thickens and becomes pointed posteriorly. The foramen magnum is small and ovoid, with arced occipital condyles lying somewhat anteriorly. The basiocciput narrows anteriorly, bears a low central keel and is flexed distinctly upward (indicating significant basicranial flexion). The nuchal region is flat and would have curved in strongly beneath the occipital plane. Internally, the lateral half of the petrosal is present, and its superior surface is minimally swollen. The palate is long and moderately broad, and appears to have been smoothly curved around the front. It is very shallow, and deepens only minimally posteriorly. The incisive foramen is large, and lies just behind the l i s . It appears to be at an oblique angle. The 11 alveoli are small, and not much larger than that for the RI2. The C alveolus is larger, but would not have housed a large tooth. The alveolus behind for the RP1 (possibly dml) is broad b/1 and very short m/d. The erupting RP2 is squarish, with the anteriorly placed, subequally sized protocone and paracone lying opposite one another; their deeply wrinkled internal surfaces are strongly divergent and their apices are peripheral, connected mesially by a thick crest. Distally a thick postcingulum runs from the small metacone to the side of the protocone. Mesially, a b/1 shorter crest (preprotocrista) arcs gently from the protocone to the side of the paracone. This tooth is wider b/1 than the comparatively small-looking M l .

EXT KIES

M l is worn, subsquare and smaller than M2 Both molars arc similar in having a thick postn tocrista that incorporates the metacone, a mcsiallv running and short preprotocrista that arcs mcsiallv around the paracone to the buccal side (the protocristac thus encircle the paracone), and a distinct postcingulum that encloses a fairly deep and moderately m/d long talon basin as it runs almost completely down the distal side of the very large, somewhat m/d compressed, and b/l wide hypoconc. The hypocone lies level lingually with the large, somewhat internally placed protocone. The postcingulum and protocristac bear conulcs, and the M2 protocone has a small protostylar pit mesially. A deep groove or fissure delineates the base of the paracone and another separates the distal side of the postprotocrista from the hypcone. M 2 is moderately deeply wrinkled, and Ml probably was also. SK 48. Fairly complete but somewhat crushed cranium, missing much braincasc bone, especially posteriorly. T h e R C - M 2 and L M 1 - M 3 arc present, plus the root for LP2 and alveoli for RI1-12. Teeth are moderately worn, and some are cracked. The face is large, but the neurocranium is neither massive nor thick-boned, despite having evidence of a sagittal crest. T h e face is relatively flat and steep, but the frontal rise behind is low. W h e n viewed from above, the moderately broad and modestly swollen glabellar region protrudes in front of the slightly retreating and s/i thin supraorbital margins ("tori" is not an appropriate descriptor). There is extreme postorbital constriction, so that the outer walls of the orbital cones form a large part of the medial sides of the temporal fossae. Continuity between the supraorbital margins, the posterior part of the frontal and the parictals is thus strongly restricted laterally. The posttoral surface is short a/p, and its posterior margin is defined by a distinct ridge created by the temporal line. The postglabcllar region is sunken, and the temporal lines, which form a scarlike border to the lateral external orbital margins, rapidly converge to form a markc frontal trigone. The orbital roofs arc slightly concave and form a modestly crisp margin with the backwardly sloping anterior supraorbital margin. These margins are uniformly thick from side to side, and are not interrupted by a supraorbital notch or foramen. The orbits were probably roundedly square, as judged from the L side, and there is a very broad intcrorbital

SWARTKUANS

region. On the L, the orbital walls are relatively well preserved, and there is no trace of an superior orbital fissure. The very medial position of the inferior orbital Assure indicates that the infraorbital canal must have lain extremely medially. The infraorbital region is broad and anteriorly facing, and the zygoma is swollen, particularly along the zygomaxillary suture, which makes the maxilla medial to the suture appear slightly concave. The frontal processes, as seen on the L, were not very tall or large, and appear to have been oriented forward, so that the plane across the nasal region was probably relatively flat. The frontonasal suture is not clearly visible, but there appears to have been some keeling along the nasonasal suture. The nasal bones were probably quite narrow, at least superiorly. T h e nasal aperture was probably quite broad inferiorly, but not very tall s/i. The nasoalveolar clivus is not very long, and flows smoothly into the floor of the nasal cavity above. It slopes down quite steeply, and is relatively flat across. It is possible that the floor of the nasal cavity was slightly stepped down inside the inferior margin. On the R, the lateral nasal margin is preserved, and is bluntly rounded. T h e modest infraorbital foramen lies far down on the face and is oriented inferiorly, with a short gutter below it. At the lateral edge of the clivus, above the canine, there is a distinct corner but no swelling of the bone (as in SK 46). The anterior root of the zygomatic arch originates above P2 and, when viewed from the front, its straight edge angles out strongly to the thickened and inferiorly muscle-scarred region of the undefined maxillary tuberosity. As preserved on the L, the zygomatic arch is very tall s/i, but is not very thick laterally. From the side it is somewhat S-shaped, rising to its midpoint and descending again to its posterior root. T h e squamous portion was probably not very long or tall. Most of the bone of the cranial roof and base is missing or undecipherable. T h e temporal fossa, best preserved on the left, is large but not huge, and is more expansive inferiorly than superiorly, being constricted above by the orbital cone. It appears that the anterior squamosal flowed smoothly on to the sphenoid, which is not angled to produce an inferior temporal fossa. The articular fossae are somewhat preserved on both sides; they are large, being deep, long a/p and quite wide. T h e anterior and posterior walls of the fossae are broadly divergent, and there is no definable articular eminence anteriorly. As better

381

seen on the L, the posterior root of the zygomatic arch takes origin above the articular fossa and extends strongly laterally. The shelf above is short a/p. On the L, it appears that the ectotympanic tube was well ossified laterally, and the moderately large, ovoid acoustic meatus is tilted slightly forward. On the R there appears to be evidence of a very low vaginal process that would have been well separated from the mastoid process, and well behind which lies a very medially placed stylomastoid foramen. The sphenoidal foramina are hard to interpret. The s/i tall medial and lateral pterygoid plates are parallel, and the lateral was much longer than the medial but was apparendy roundly confluent with it near the maxillary pole. The occipital condyles are partially preserved. As best seen on the R, they are small but strongly arced a/p, and somewhat anteriorly placed on what probably was a rather small, ovoid foramen magnum. The apparendy narrow basiocciput is swollen slightly externally and appears to have risen steeply, producing extreme basicranial flexion. The palate is distorted, but appears to have been quite long and moderately broad. The anterior teeth ran straight across between the Cs, and the cheektooth rows are straight and were probably subparallel. The palate deepened markedly from front to back, with rather straight walls posteriorly. The alveolus for II is much larger than that for 12, and subequal with the small-crowned and slighdy obliquely oriented canine. The small and m/d narrow C has a well-developed margocrista, at least mesially, and is much smaller than the PI; in profile the perimeter of the crown presents a tight curve. P i and P2 are subequal in b/1 width, P2 being slightly longer m/d. Both Ps bear bulbous, subequal and slightly mesially shifted paracones and metacones that are separated by a deep longitudinal groove. Each tooth presents evidence of a moderate postcingulum distal to the groove. The Ms slightly increase in size from M l to M2 and more markedly to M 3 . From M l to M 3 the protocone becomes larger and more distended lingually, and the postcingulum also appears to become larger b/1. On M 3 the postprotocrista encloses a distinct and deep talon basin. The hypocone becomes increasingly truncated and thus smaller lingually, and the paracone also is increasingly truncated and thus smaller lingually from M l to M 3 . The hypocone is m/d compressed and somewhat b/1 wide on all molars. On M3 the hypocone is separated by a deep groove or fissure from a very thick postprotocrista that incorporates the small

382

SITE

mctaconc region; this was probably also the case with M 1 - M 2 . On all three the prcprotocrista runs mcsially around the base of the paracone, and the trigon basin is very constricted along the inner face of this cusp. On the RM2 and the LM3 there is sufficient detail detectable to make it very likely that the protocrista on all Ms surrounded the mctaconc. The lingual side is more bulbous than the buccal side in all molars. SK 49. A flattened partial cranium with little useful morphology, but preserving R and L broken Pis, and P2s through M3s, all worn and cracked to varying degrees. The posterior pole of the maxilla was very tall. There is evidence for a low sagittal crest and a relatively pronounced superior nuchal line with a moderately developed, downwardly pointed and narrowly V-shaped external occipital protuberance. Also, the superior nuchal line is cresdike lateral to the protuberance and as far as the posterior mastoid region. Breakage shows the mastoid was highly pneumatized, with small to moderate air cells. A thick crest lies horizontally above the mastoid region, and posteriorly protrudes away from the cranium, creating a notchlike area beneath it. Suture-like morphology lateral to this suggests that the parietal obliquely overrode the occipital bone. What remains of the lambdoid suture indicates that the occipital plane was extremely short s/i. The palate was apparently very shallow anteriorly, deepening somewhat posteriorly. The broken RP1 preserves a deep m/d-oriented groove at the bases of the mostly missing paracone and partially damaged and apparendy large and mcsially shifted protocone; there is also evidence of a very thick postcingulum. P2 is large and at least as wide b/1 as the M l , although it is somewhat shorter m/d. The RP2 is more similar to that of SK 65 (see below) than the LP2 is, but both P2s are longer m/d than the P2 of SK 65. In the RP2 a deep fissure lies quite buccally between the bases of die very internally truncated and centrally placed paracone and the very large, m/d long and mcsially shifted metacone; this fissure lies closer to the midline of the crown on the L. In both, the buccal side of the crown is more tightly curved than the lingual side and thick protocristae course to the sides of the paracone; on the R, they terminate in distinct buccal swellings. The Ms increase in b/1 width markedly from M l to M2, and less so from M2 to M 3 . M l is shorter m/d than M 2 and M3. The metacone region becomes more truncated and thus smaller from M l to M 3 . The m/d

ENTRIES

somewhat compressed hypocone is well developed in all three Ms, swelling them somewhat distally, but it also becomes b/1 narrower from M l to M3 with a concomitant increase both in b/1 length of the thick postcingulum and in the size of the talon basin. The postcingulum is beaded and the enamel moderately cuspulatcd on M 3 , less so on M2. These features were probably originally quite pronounced on all Ms. As better preserved on the L M 3 , thick protocristae enclose a very internally truncated paracone. A fissure lies between the base of this cusp and the postprotocrista and another between this crest and the hypocone. SK 52. Subadult partial face with part of R temporal and palate, R and LI2, alveoli for other anterior teeth, R and L P 1 - P 2 , R M 1 , mesial part of L M 1 , alveoli for R M 2 and still erupting RM3. The Ps are fairly unworn, but the Is and M i s are quite heavily worn. The R orbital region, which is complete only to the orbital midline, appears to have been tall, and the flattish-in-profile supraorbital margin is forwardly facing and tapers markedly laterally. The deeply interdigitated zygomaticofrontal suture is vertically rather than horizontally oriented. The rather concave orbital roof angles quite sharply on to the supraorbital surface, which is defined above by the medially running temporal line. Posteriorly there is some postorbital constriction, but not an extreme amount. Breakage shows that if there had been a sinus in the frontal region, it did not extend far laterally. Breakage also indicates that the frontal lobe extended quite far but not fully over the orbital cone. T h e floor of the orbit is well preserved and shows a deep infraorbital groove that was not ossified over and continues quite far forward in the orbit. The orbital cone itself would not have been very deep. T h e relatively large infraorbital foramen lies only moderately below the infraorbital margin; below it, a shallow gutter runs down toward P I , giving the impression of a modest snout in front of it. T h e not very massive zygoma is anteriorly facing, and seen from in front the anterior root of the zygomatic arch, which originates over P2, curves quite sharply out and up before flexing strongly backward. The maxillary tuberosity is laterally facing, as is the muscle scar it bears. The nasal aperture is preserved at the bottom and is fairly narrow across, with smoothly rounded corners to the inferior margin but fairly sharp margins higher

SWART

up. The floor of the nasal cavity is quite flat and flows smoothly out on to the flat-across and only modcritelv long nasoalveolar clivus, which slopes forward only modestly. The incisive fossae lie not far behind the'margin of the nasal aperture, and as judged by the R are fairly large and funnel-shaped. The maxillary sinus intrudes a bit into the region of the floor of the nasal cavity, at the level of M2. The R temporal is represented by part of the squamosal and mastoid regions, and most of the zygomatic process. The posterior root of the zygoma takes origin at the posterior part of the fairly deep articular fossa. It expands laterally as it runs forward, to reach its greatest width in front of the fossa, where there is also a small eminence laterally. What is preserved of the zygomatic arch suggests a modest flare. The moderately thick-walled ectotympanic is appressed directly to the mastoid, and the auditory meatus was probably not very large. The mastoid is not very swollen laterally, and is pervaded by small to moderate air cells. The palate is moderately long and wide, and is gently curved around the front from the lateral incisors to the premolars. The palate is very shallow anteriorly and deepens somewhat posteriorly, but it is not deep and does not have notably vertical sides. The large single incisive foramen begins just at the level between PI and P2, and continues forward as a moderately deep gutter. The midline palatal suture is thickened and raised. The II alveoli would have housed roots much larger than those of the I2s. The complete RI2 crown is minuscule, and rounded distally. The modest C alveoli are oriented obliquely, and probably housed teeth of only moderate size. Pis are smaller than P2s, but both Ps have large, bulbous and medially shifted protocones that are separated by a deep horizontal groove from smaller, centrally placed paracones that are bounded on each side by thick protocristae (the posterior crests are beaded; cf. RP2 of SK 49). On the P2s, especially, the "metastylar" region is developed. Ml has a large, m/d compressed, b/1 long hypocone and a rather small metacone. The lingual side is rounded from top to bottom as well as from side to side. There is a small wedge-shaped depression in the buccal side between the paracone and the metacone. It is obvious that there was a thick postprotocrista that was confluent with the metacone region; a still fairly deep groove separates this structure from the hypocone, from which a very b/1 short postcingulum runs to the side of the metacone region. A smaller groove lies between the postprotocrista and the base

KiiANs

383

of the paracone. The trigon and talon basins would have been minimal. M2 had three broad and distinctly separated roots. The M3 crown is deeply but sparsely wrinkled. It is longer m/d than wide b/1 and is distended d/1 by a large hypocone, from which a thick but short postcingulum runs to the small metacone. The very thick and gently beaded preprotocrista runs around the paracone to the parastylar region. The lingual side is bulbous and the buccal side is straight. SK 65. Part of a L premaxillary/maxillary region, including part of the floor of the nasal cavity and a portion of the medial wall. Preserves I I - P 2 , all very worn. The floor of the nasal cavity flows smoothly onto the very strongly downwardly curved and quite short nasoalveolar clivus. The posterior pole of the nasoalveolar clivus had extended far back into the nasal cavity (as judged by the long plane of the clivus that is preserved in the nasal cavity). The inferior margin of the aperture is continuously curved, as apparendy was the region behind it. At least inferiorly, the lateral margin of the aperture is rounded. Part of the L incisive canal is preserved, and its most posterior extent does not lie far within the nasal cavity. Part of the maxillary sinus is preserved, extending quite far forward. In front, the palate would have been essentially straight across; it is shallow behind the Is, and it appears to become deeper quite quickly. The Is are both somewhat spatulate. The 12 is noticeably smaller than the II, and its lingual surface is concave and bordered by margocristae. The exposed II root is long. The C, though absolutely small, is quite large compared to the Is, and was probably tall though narrow-crowned. Its buccal surface is somewhat rounded, and its flatfish lingual surface angles slightly to a small basal heel. P 1 - P 2 are proportionately much larger than the anterior teeth, and, judging from its distal interstitial facet, P2 was large relative at least to the b/1 width of the M l . PI is somewhat shorter m/d than P2, but is only slightly narrower b/1. Both have large, swollen protoconcs that were situated probably just mesial to the paracones. Both have evidence of a small posterior fovea, and P2 has a small, stylar-likc swelling on the distal side of the paracone that is the terminus of a fairly thick postprotocrista. A deep horizontal groove lies between the bases of the internally placed protoconc and internally truncated and peripherally placed paracone. The two broken buccal roots of P1-P2 are quite divergent.

384

SITE

SK 65a is an isolated upper RC. Its stout root is broken and the crown is quite worn. It resembles its L equivalent in SK 65. SK 79. Very squashed partial cranium, with crushed and shattered, worn cheek teeth and alveoli for anterior teeth. T h e glabellar region is preserved; it protrudes slightly. There are very short and shallow posttoral and postglabellar sulci, and the frontal rise behind glabella is low. Interorbital space is broad and flat, and the superior orbital margins are thin s/i, arcing gently and broadly up from their more inferior confluence in the glabella region. T h e moderately short and broad nasoalveolar clivus flows smoothly out of the floor of the nasal cavity and is flat across above the somewhat lumpy tooth roots. There is no well-defined inferior margin of the nasal aperture, whose corners are smoothly rounded. Anteriorly in the midline are a pair of small, vertically pointed anterior nasal spines, immediately behind which lie the incisive fossae. T h e anterior root of the zygomatic process is partially preserved on the L; it is thick a/p, flares out arcuately and quite strongly laterally, arising relatively close to the region of M 1 - M 2 , and apparently faced forward. T h e region of the zygomaticomaxillary suture is quite thickened, delineating a concavity below it (and thus also below the infraorbital region laterally). T h e malar tubercle is thickened, and the muscle scar lies inferiorly. Behind it the zygomatic arch runs straight back. As seen on the L, the lateral pterygoid plate is longer a/p than the medial, though the two are confluent inferiorly. T h e palate is relatively long and broad, and quite shallow anteriorly, though it deepens considerably posteriorly, with almost vertical side walls. T h e single large incisive foramen lies level with the P i s . T h e alveolar margin is essentially straight between the C s . T h e I I alveoli are round, and larger and longer m/d than the 12 alveoli. T h e R C alveolus is larger than the l i s , and is obliquely oriented. P i s were apparently smaller than the P2s; the latter were short m/d compared to their b/1 width, which was at least equal to the width of the M l . The Ms apparently increased in size M 1 - M 3 , most markedly from M l to M 2 , less so from M 2 to M 3 . From M l to M 3 , the protocone region becomes larger as the metacone regions become smaller. T h e hypocone is large in all, and on M 1 - M 2 it lies buccal to the metacone region. The M3s preserve a very thick postcingulum that encloses a fairly deep talon basin as it runs buccally to

ENTRIES

the side of the metacone from the side of a verv IA compressed, b/1-cmphasized hypocone. SK S3. Cranium with badly crushed braincase and the face a little less so. All teeth are present, but moare quite damaged and heavily worn. T h e fairly thin-boned neurocranium bears traces of a sagittal crest. As seen on the L, the superior orbital margin is thin s/i, at least laterally. There are no certain traces of supraorbital pneumatization. As preserved on the R, the infraorbital foramen is small, and lies moderately below the inferior orbital mar
SWARTKKAXH

The C was smaller in circumference than the P I . Both Pis are wider b/1 than long m/d. P I is smaller than P2, which appears large relative to M l . The Ms increase in size M 1 - M 3 , with the protocones becoming larger in this sequence as well. As seen on the LM2-M3, the mctacone is smaller than the paraconc, while the hypoconcs are large. O n the LM2, the hypocone is apparently compressed m/d but distended b/1, and a short postcingulum courses from it to the side of the mctacone. O n M 3 , the hypocone is swollen distally by the longer m/d and the postcingulum is much thicker; the hypocone also docs not extend as far lingually as the protoconc. There is also evidence that at least the postprotocrista was very thick and probably had been confluent with the metacone region. SKW II. Partial lower face and palate, somewhat reconstructed, preserving the region to the R of the nasal aperture, the inferior part of the frontal process of the maxilla, the base of the anterior root of the zvgomatic arch, alveoli for R C - L C , broken roots of L P 1 - M 1 , broken crown of M 2 , L M 3 and R P 1 - M 3 . The M3s are the least worn and cracked teeth. In profile this is a very short, straight and steep lower face with only the slightest hint of anterior extension of the nasoalveolar region toward the alveolar margin. From the front the preserved lower portion of the lateral crest (margin) of the nasal aperture is blunt, and it fades out anteriorly on the face below the point where the somewhat crisp "spinal" crest arcs down and then up to meet its antimere in the midline in front of the base of the broken vomer (the inferior portion of the nasal aperture looks like a rounded "W"). Lateral to the R of the nasal aperture the bone is flat and faces forward. As preserved on the R, the mildly concave floor of the nasal cavity lies below the "spinal" crest (steps down) and extends straight back. Anterior to the inferior margin of the nasal aperture the broad and essentially featureless nasoalveolar clivus is gently and concavely slung from a very m/1 broad and flattish R facial "pillar" to what appears to be the medial part of a L "pillar." The R pillar runs up from the alveolar margin of I 2 - C and medially becomes confluent with the downward course of the blunt lateral crest, while its lateral side is defined by a blunt vertical corner that extends superiorly only as far as the preserved medial portion of what was a fairly large, probably downwardly facing infraorbital foramen. This foramen probably lay about midway up the length of the nasal aperture. The flat, vertical and anteriorly facing anterior root of the zygomatic arch is set back

385

from this "corner." This anterior root was long a/p, as it emerged well up from the region of the P 2 - M 1 , and it rose steeply, with moderate lateral flare. The palate is shallowly sloped anteriorly, but deepens rapidly posteriorly; the side walls are vertical and the single, large, anteriorly widening incisive foramen lies level with the P I - P 2 septum. It is very long a/p, and its front is somewhat tight curved. The very a/p long cheek tooth rows arc moderately divergent. The anterior teeth were relatively small and relegated to the very front of the dental arcade, which appears quite tightly packed compared to the expansive cheek tooth rows and their large-crowned teeth. As better preserved on the R, the roundedly triangular I I alveolus is longer m/d and wider b/1 than the 12 alveolus and even wider b/1 but shorter m/d than the C alveolus. The P2 is much wider b/1 than the P I and the M l , and also much longer m/d than the P I . The P I is more tightly curved lingually than the P2 and both are broadly rounded buccally. It appears that in both the centrally situated paracone was peripherally placed and its base truncated internally, with a horizontal groove (probably originally deep) between it and the much larger and apparently slightly mesially situated protocone. P2 most likely had thick mesial and distal cristae that terminated in swellings on either side of the paracone. The M l is much smaller overall than the subequal M 2 - M 3 ; the latter is more distended distally. Better seen on the R, the M 3 has thick protocristae, emanating from a very large protocone, that encompass a tall but internally truncated paracone that is separated from the preprotocrista by a fissure. The postprotocrista incorporates the metacone. A thick but b/1 short postcingulum courses to the side of the metacone region from the large, m/d moderately compressed and b/1 extended hypocone, which is separated from the postprotocrista by a fissure. The hypocone is not as lingually distended as the protocone, which bears a distinct pit (originally cingulum) buccally on its mesial surface. The surface is quite deeply crenulated. Grooves on M 1 - M 2 suggest similar morphological detail. Overall the mctacone region becomes truncated and the hypocone and postcingulum enlarged in the sequence M 1 - M 3 .

Taung Lower Dental Morph (includes SK 61, 62, 64, 3978) SK 61. A partial juvenile mandible with Rdm2 through Ldm2, with RM1 erupting. Corpus behind

386

SITE

these teeth is missing. L d i l - d i 2 are quite damaged; R d i l - d i 2 are crushed back, and Rdi2 is cracked. All deciduous teeth are very worn, the dm2s the least. T h e bone of the corpus is thick but not deep, especially in the region of the M l since it shallows dramatically from front to back. Seen from the side, the front of the symphysis curves very gently back, reflecting the curvature of the central incisor root. The profile then slopes back and down to curve broadly around into the inferior margin. Seen from the front, the bone of the symphysis is distended around roots of both dils, with a depression between them and larger shallow fossae on either side. Below and to either side of the dis, the bone is smooth. Below the des, just above the inferior margin, the bone is slightly swollen, though not into noticeable tubercles. Viewed from above, the symphysis is generally broad and gently arced across. This contour is interrupted by the bulges of the I I roots. O n the R there are four small mental foramina, three in a vertical column below the distal portion of d m l , the inferiormost slightly posterior. Level with the middle of these three is the fourth foramen, lying under the mesial portion of dm2. T h e bone is swollen outward around the foramina and the region anterior to them (probably reflecting the crown of a developing tooth). A similar swelling is found under d m l on the L, where there are only two small mental foramina, one above the other, under the distal part of d m l . Internally there is a short, moderately sloping postincisal plane. At the posterior level of the dm Is this turns downward almost vertically to a relatively broad, shallow pit lying above a slight thickening. Seen from above, the internal curvature is quite tight at the front, though the tooth rows are somewhat divergent posteriorly. Seen from the rear, the broken cross section of the L corpus is broadly ovoid. As far as it is preserved, there is no sign of a mylohyoid line or a submandibular depression. Barely perceptible digastric fossae lie well forward on the thick lower margin. As preserved on the R, dil is very narrow m/d, with a small lateral flare. The di2 is markedly larger than the dil and is still relatively narrow though slightly flared on both sides. Both dis were evidently very tall crowned. The Rdc is more worn than the L, but both were relatively small teeth, especially compared to the Ldi2. They are distended somewhat distally but more markedly mesially such that the crown flares away from the neck. The apex of each was situated mesial to the midline, and distal to it lies a small

ENTRIES

heel1. Lingually the region of the heel is delineated b latively deep vertical groove. Buccallv ,y a relatively Buccally t1w« there :. is ad"' pression in the region of the heel, much more P i £ nounced on the L than on the R. These would have been tall-crowned teeth. T h e d m l s are relatively long, somewhat narrow b/1 and long m/d. They are noticeably smaller than the dm2s behind. T h e L is more worn than the R I outline they taper slightly mesially; they are gently curved around the distal side, and mesially they are distended in the buccal corner of the tooth by a b/1 narrow but thick paracristid. O n both, behind the m/d short paracristid, which is more evident along the protoconid, is a relatively deep but truncated trigonid basin that is bound distally by a thick short cristid that runs between the distal aspect of the protoconid and the mesial part of the metaconid (thus there are two cristids enclosing the trigonid basin mesially and distally). A s better seen on the R, the protoconid and metaconid were subequal in size and anteriorly positioned. A moderately deep notch on the buccal side separates the protoconid from the apparendy larger hypoconid, which itself is marked buccally by two short, moderately deep notches; there is some cingulid at the base of each notch. T h e distal notch appears also to delineate the margin of the small, somewhat buccally placed hypoconulid; either an extension of the hypoconulid runs to the entoconid or there was a small conulid between these two cusps. The quite large and prominent entoconid (in spite of the amount of wear) lies opposite the somewhat larger hypoconid, whose base extends well across the midline to broadly contact the base of the former. T h e dm2s are relatively long, bulbous teeth, slightly more curved on the buccal than the lingual side giving a "twisted" shape to the tooth. The di>tal part of the tooth seems twisted d/1 due to the m/1 orientation of the buccally placed hypoconulid and V&e presence of a d/1 groove and conulid between it and the entoconid. As better seen on the L, a * :k paracristid runs mesially between the subequaiu J mesially shifted protoconid and metaconid. A ^ crest runs between the apices of these two cuspN ating a basin with the paracristid. On both «d deep but small notch lies between the protoconu: the slightly larger hypoconid, whose some- .-t wedge-shaped base extends slightly across the f line, of the tooth and contacts the m/d elongate r conid and squared-off base of the entoconid. " kling of the enamel in the relatively ni/d long

SwAUTKUANS

moderately b/1 broad taionid basin gives the impression that there is a ccntroconid internal to the hvpoconid, although it is not really separate from the latter. The entoconid is subequal in size to the hvpoconid and lies distal to it, thus moderately far behind the metaconid. There is a deep, small notch between the hypoconid and the hypoconulid, which is slightly buccally shifted across the midline, while its m/1 oriented base makes a fairly broad contact with the entoconid; there is some cingulid at the base of each notch. A moderately deep but narrow groove runs between the facing surfaces of the hypoconulid and entoconid. A small cuspulid lies distal to this groove, on the edge of the entoconid. The apices of the buccal cusps are slightly internally placed, while those of the buccal cusps are very peripheral. Thus there is more buccal than lingual slope to the sides. The unworn M l is markedly larger both b/1 and m/d than the dm2, and looks "puffier." T h e cusps are swollen at their bases are but also very tall. T h e occlusal surface is deeply grooved, producing, as on dm2, a pseudocentroconid at the base of the hypoconid. Low down mesially on the bases of the mesially shifted protoconid and metaconid is a thick but b/1 narrow paracristid, whose shelflike surface is somewhat wrinkled. Pillars on the internal surfaces of the protoconid and metaconid converge in the midline behind this cristid (raising the question of whether the double crest impression in more worn teeth might simply be an artifact of wear from a condition such as this). A deep notch on the buccal side, with a bit of cingulid below it, separates the protoconid and hypoconid. T h e hypoconid is somewhat smaller than the protoconid and its wedge-shaped base extends slightly beyond the midline of the crown, contacting the m/d long metaconid and entoconid more or less equally. A notch separates this cusp from the slightly smaller, buccally placed, wedge-shaped hypoconulid whose m/1-oriented base contacts the entoconid rather broadly. T h e entoconid appears to be the largest cusp; it lies somewhat distal to the hypoconid. Grooves run down the facing surfaces of the entoconid and hypoconulid, to converge at their junction. A distinct, moderately large cuspulid lies near this juncture, primarily on the entoconid and on the distal side of the groove. T h e buccal cusps are quite internally placed, and the lingual cusps are quite peripheral. There is a hint of a mctastylid on the distal edge of the metaconid. In general shape, this is a subcircular tooth that actually appears more rounded in

387

its mesial half and is a little more constricted distally, with a distolingual distension. SK 62. Partial mandible lacking L ramus and R corpus behind the dm2. Teeth present are L d m l - d m 2 with M l partially seen in its crypt and R d c - d m 2 and LI1 erupting; the dmls are quite heavily, and the dm2s noticeably, worn. Also present arc the roots of LdI2 and Ldc; a small di2-looking crown is glued on the di2 root, which is too large

for it. Th is mandible is similar morphologically to the others in this group in preserved regions. The corpora arc relatively quite tall at the symphysis and thin out somewhat posteriorly. T h e profile of the symphyseal region curves a bit forward from below the alveolar region and then down and back to the inferior margin. T h e inferiorly rounded (in profile) inferior boundary of the long, moderately sloping postincisal plane is part of a thickening that is continuous along the internal aspects of the corpora. Below this, toward the midline, the bone is broadly but not too deeply depressed, and further below the inferior margin is slightly swollen internally. T h e erupting II crown is not very tall, but its sides diverge markedly from an m/d narrow neck to the incisal edge. T h e lingual surface bears relatively thick but low margocristids that diverge from a minimally swollen base and rise above the more excavated surface between them. T h e small b/1 and somewhat compressed Rdc is worn smooth. Its lingual surface is essentially flat and the buccal surface somewhat convex. A short and curved mesial edge, and a longer and also curved distal edge, descend from the blunt tip. As better seen on the L, the d m l is a somewhat wedgeshaped tooth, being broad b/1 distally and distended m/b by the paracristid. T h e m/d long metaconid and smaller protoconid apices lie opposite each other and a deep notch separates the latter cusp from the larger hypoconid, whose apex lies across from the much smaller and distally situated entoconid. There may be a small (worn) conulid between these two cusps. T h e much b/1 wider and markedly m/d longer dm2 is broadly but shallowly rounded distally and tapers gently to its more tightly rounded mesially side. A thick paracristid in front of the protoconid and m/d longer metaconid bounds a small but deep basin that is bounded distally by a thick crest (worn confluent bases of the two cusps) which, in turn, bounds another small, deep basin that is defined distally by another

388

SITE

thick crest. Peculiar wear has obliterated cusp distinctiveness, but grooves indicate that cusp shapes and contacts were like those of SK 61 and SK 64. These and other grooves indicate that the crown had been deeply crcnulatcd or cuspulatcd (perhaps not as greatly as SK 61). The visible part of M l indicates that it is deeply grooved, producing what appear as very thick crests that emanate from the apices of the mctaconid and the protoconid and then converge distally at the midline of the crown (cf. Taung). The wedge-shaped hypoconid base extends a bit across the midline of the crown, cutting in front of (thus truncating) the entoconid to contact the m/d elongate metaconid. The prominent, buccally placed hypoconulid is quite large and contacts the entoconid somewhat broadly. SK 64. Fragment of juvenile R mandible with dml in place and dm2 almost fully erupted. Also partial distal alveolus of dc. At the rear, part of the gonial angle is preserved. Relatively small, gracile individual, especially compared to SK 61. At the level of dml, the corpus is neither deep nor very wide. It appears that the corpus was taller anteriorly, and in what is preserved, the corpus does become shorter s/i to the rear. At its anterior broken point the margin of the corpus seems to be turning inward, suggesting a tight curve at the front of the jaw. A moderately sized mental foramen lies below dml. Toward the distal end of dm2 the inferior margin is concave, but it is distended downward posteriorly by the gonial region. The anterior margin of the ramus is sloped back somewhat at its root, but appears to be turning more vertically at the point where it is broken. The gonial region is moderately curved at its inferior border, and rises quite sharply behind. Externally, the surface of the gonial region is smooth. Internally its posterior edge bears two swellings, the superior one being the more pronounced. The mandibular foramen lies just above the level of the dm2, and points up and back. It lacks a lingula, and the margins of its aperture are strongly divergent. A distinct but somewhat shallow mylohyoid groove runs down and forward from the aperture. There is no sign of a mylohyoid line or a mandibular fossa. The partially preserved dc alveolus is quite buccally placed and indicates a root of moderate size and length, dml is markedly smaller and more mesially truncated than dm2. dml is somewhat rounded distally and tapers slightly mesially. Buccally, it is

ENTRIES

distended mesially by the swollen terminus of a thi V paracristid that runs from the base of the mctacon'H to the level of the apex of the protoconid. Distal to 't is a relatively large, deep trigonid basin that is enclosed distally by the apprcssed bases of the protoconid and metaconid (further wear would make it aDpear that there was a cristid between the protoconid and metaconid, cf. SK 61). The quite m/d elongate mctaconid is somewhat larger than the b/\ compressed protoconid, but their apices lie opposite one another. A thin vertical groove separates the protoconid buccally from the somewhat larger hypoconid. The entoconid is somewhat smaller than the hypoconid, and lies somewhat distal to it, and thus is quite separated from the metaconid. Most of the relatively small wedge-shaped hypoconulid lies buccal to the midline, and makes a modest contact with the entoconid. A thin vertical buccal groove separates this cusp from the hypoconid. There is a small but distinct shelf (worn conulid) between the bases of the entoconid and the hypoconulid. The dm2 is relatively long, narrow and somewhat ovoid, and is somewhat "twisted" d/1. The surface of the tooth is deeply but sparsely grooved, making it appear that there is a centroconid internal to the metaconid as well as another pseudocentroconid internal to the hypoconid. These extensions of the cusp bases fill in the talonid basin. The very m/d elongate, distally metastylid-bearing metaconid and much smaller protoconid apices lie opposite each other and quite far forward on the tooth. A thick paracristid, bearing an m/d-oriented groove in its midline, runs between the bases of these two cusps. This crest encloses a relatively large but deep trigonid basin that is bounded distally by pillars that descend along the internal surfaces of the protoconid and metaconid (again, it worn, these pillars might appear as a crest). There is a deep and modestly b/1 wide pit between the metaconid-protoconid juncture, which gives the tooth an appearance of "twinned" mesial basins. A tall, thin buccal groove separates the protoconid from the larger hypoconid, whose wedge-shaped base barely extent across the midline of the crown to contact the metr conid and slightly internally truncated cntocop: bases equally. A thin, vertical buccal groove scpanu* * the hypoconid from the moderately large, m/l-t ented hypoconulid that lies mostly buccally, «* • whose base makes a broad contact with the cntocor. The entoconid is noticeably smaller than hypoconid and lies distal to it, thus far from

SWARTKHANS

metaconid. A distinct, d/1-oriented and wedge-shaped <;helflike structure separates the bases of the hypoconulid and entoconid peripherally. SK3978. Juvenile mandible lacking corpus behind Rdm2, and an increasing amount of the L corpus from the inferior margin toward the alveolar from behind the symphyseal region and posteriorly. Also missing most of the lateral surface of the remaining part of the L corpus and of the ramus, of which only the middle portion remains. Also preserved are R and Ldml-dm2, the alveoli for the anterior deciduous teeth and the crypts for M l (the L is obscured by matrix). In profile, the rather straight-faced s/i tall symphysis is oriented down and back and presumably would have curved around the inferior margin. On both sides, under the dml, is a large mental foramen surrounded above and in front by a number of small to very small foramina. What remains of the L ramus curves up very severely behind the dm2 and also swings laterally away from the corpus. Internally, the moderately long and sloping postincisal plane overhangs the depressed genial region below it, and its inferior margin is confluent with a general internal swelling of the walls. The dil alveoli are smaller, especially m/d, than those for the di2s, while those for the dcs are in all dimensions huge by comparison. The dm Is are much narrower b/1 and shorter m/d than the appreciably larger dm2s. The dm Is are essentially the same b/1 width for much of the length of the tooth, but, just buccal to the midline, are distended mesially by a somewhat thin paracristid that courses forward from the protoconid before turning strongly down and back to the base of the m/d elongate metaconid. As better seen on the L, the paracristid encloses a trigonid basin of moderate size that is bound distally by another thin crest between the mesial portions of the protoconid and metaconid. There is a deep notch on both sides between the protoconid and the larger hypoconid, at the base of which is a bit of cingulid. The wedgeshaped hypoconid extends across the midline of the tooth and cuts in front of the (thus truncated) entoconid to make a broad contact with the metaconid. As seen on the R, there is a small conulid between the smallish and slightly buccally shifted hypoconulid and the entoconid, with which it makes modest contact. On both sides, the somewhat b/1 emphasized dm2s have a noticeably b/d "twist" to them, due in

389

part to the b/d-oriented crest between the buccal hypoconulid and the entoconid, and the ledgelike structure behind it. Mesially there are two basins. One (fairly deep and wide b/1 and somewhat long m/d) is enclosed in front by the moderately thick paracristid coursing mesially between the apices of the m/d elongate metaconid and protoconid and behind by another crest between these cusps. The second lies behind this latter crest and a low third crest running between these cusps. The thickly wedge-shaped hypoconid broadly contacts the entoconid (truncating it), but it makes a smaller contact with the metaconid. The very buccal hypoconulid is m/b-oriented, and its base makes a broad contact with the entoconid. SK 55 Dental Morph [includes SK27 (upper) and SKX 4446 (volume 2, lower)] SK55a is a crushed palate containing R and L11-12, R and LC (?deciduous), R and LP1, Ldm2 very worn, part of R dm2, L M l and part of LM2. All teeth are worn to some extent. SK 55b is a crushed partial mandible, with R corpus almost to M3, L corpus to M2. Very weathered, containing partial roots of LI2 and C, with LP1, damaged Ldm2, very damaged Rdm2, R and L M l , somewhat worn, RM2, mesial half of LM2 and crown of RM3, possibly unerupted and plastered into the specimen. Also, the RP2 is just showing through the bone. Given the similar state of mineralization and similar mix of deciduous and permanent teeth in both of these specimens, it seems reasonable to suggest that SK 55a (which represents an upper dental morph) and SK 55b (which represents a lower dental morph) together represent a complete dental morph. 1. SK 55 Upper Dental Morph (includes SK 27) SK 27. Highly s/i compressed cranium with LI2, Ldm2, LP2 unerupted and R and L Mis, plus three isolated teeth: LC with broken root, LP1 or P2 with broken root and Rdm2 crown lacking roots. May not be associated. The nasal bones themselves are quite narrow superiorly, but fan out strongly infcriorly. The nasonasal suture lacks a crest. Skull lacks a sagittal crest; the coronal suture is preserved and shallowly interdigitated, but is not segmented. The sagittal suture is also unsegmented, but has slightly deeper intcrdigitations. The lambdoid suture is unsegmented and finely interdigitatcd. On the L a thick temporal scar lies on the

390

SITE

parietal some distance from the sagittal suture. T h e squamosal was probably long and not very tall. T h e parietal notch is very shallow, and the relatively long and horizontal parietomastoid suture is finely interdigitated. As seen on the L, the articular fossa was probably deep and not very wide m/1, though it could have been long a/p. Part of the tubular cctotympanic is preserved on the R, and was probably small and ovoid. T h e round L foramen ovale lies lateral to the base of the lateral pteryoid plate, and the foramen spinosum lies well anterior to the modest medial articular tubercle but is probably still just in the sphenoid. The upper part of the mastoid region, and thus also the upper part of the occipitomastoid suture, extends posteriorly beyond astcrion. From astcrion the lambdoid suture slopes gently up for some distance, then is damaged. The mastoid processes are small and probably did not project much interiorly. They are oriented somewhat down and forward. O n the L there is a shallow but m/1 wide mastoid notch that is bounded by a long, wide occipitomastoid crest. T h e foramen magnum was probably ovoid and relatively small. T h e occipital plane was probably not very tall, though it was evidently quite broad. On the L there is a shallow but m/1 wide mastoid notch that is bounded by a long, wide occipitomastoid crest. The LI1 is fairly large and tall crowned, although it is somewhat slender m/d. It flares somewhat laterally and is slightly concave lingually as well as being a bit distended mesially near the incisal edge. T h e tallcrowned partial RC is barely visible. T h e very worn Ldm2 is subsquare, with a b/1-distended but somewhat m/d compressed hypocone and a short and moderately m/d thick postcingulum emerging from it that tapers as it courses along the side of the metacone, eventually melding with it before reaching the buccal side. A more or less b/1-oriented groove delineates the hypocone from the rest of the crown and continues on to distinguish the postcingulum. T h e paracone and metacone are moderately large and the protoconc was much larger. As better seen on the L, the M l is somewhat longer m/d than wide b/1. T h e large, internally placed protocone bears a distinct protostvlar pit mesially, and a larger pit separates it distally from the large but m/d compressed hypocone. A thick precingulum runs from the protostylar pit to the base of the paracone, which is subequafin size to the metacone. These cusps are peripherally placed. The tngon basin is very restricted, to the center of the crown. The hypocone is m/d compressed and extends

ENTRIES

b/1 just buccal to the inner side of the base of tK metacone, and a very thick and long postcintrul runs from its lingual side to the distal side of the h metacone, enclosing a b/1 wide but m/d short talo basin. T h e lingual side of the tooth is slightly more bulbous than the buccal side. SK 55a. This palate is all crushed; there arc no indications about the nasal cavity. l i s arc cracked and very worn, very spatulatc and laterally flared. There is some lingual concavity, and possibly low margocristac near the base lingually. As seen best in the L12, the shape is different from I I : smaller and thinner m/d with probably a more curved and truncated distal edec though this tooth is slightly excavated lingually. The Cs, as they sit at present, are small and not very tall crowned. Looking down, they are slightly ovoid in outline, quite rounded around the base lingually and bulbous buccally. T h e crown was probably pointed, with subequal mesial and distal edges. The lingual surface is gently curved, with low margocristae. PI appears very large compared to both the anterior and the molariform teeth. It is about as wide b/1 as the d m l , though it is shorter m/d. It has a well-developed, bulbous and quite mesially positioned paracone and protocone. These cusps are opposite and far apart from one another, though they do not lie on the periphery of the tooth. A stout beaded postprotocrista runs distally and then directly lingually to the paracone, and encloses a narrow but deep fovea. A slightly beaded prcprotocrista runs directly to the side of the paracone. As seen on the less worn R P 1 , the inner surfaces or the cusps are quite creased. T h e lingual and especially buccal sides of the tooth are quite swollen and rounded. T h e worn dm2 has little morphology preserved. It is quadrate, with rounded corners, and had a large hypocone. T h e metacone was situated clo^c to the paracone, and there was probably a stout postcingulum between it and the hypocone. The M ~ : s somewhat worn, and is relatively long and narrow m< v. It has a very large and bulbous protocone *-• hypocone, with internally placed apices. The paraco. and slightly smaller metacone arc more periphery • placed. T h e small trigon basin is very truncated a: buccally positioned. A very stout postcingulum si from the side of the metacone down to the m compressed but b/1 expansive hvpocone, and enclose: narrow, deep and somewhat b/1 wide basin which, its lingual extent, extends between the hypocone ^ the postcingulum. The lingual side of the tooth is q^l>

S\VAR

bulbous. The buccal side is straighter, apparently with notch between the paracone and metacone. The preserved mesial part of the LM2 is flat in the region between the paracone and protocone, with a small elevation centrally. 2. SK 55b Lower Dental Morph (includes SKX4446) SK55b. This mandible (as judged from the L) has a relatively tall corpus, especially compared to tooth height; and although somewhat b/1 thick it is not excessively so compared to its s/i height. It appears that the postincisal plane was very long and only gently sloping; at about the region of M l the internal surface appears to have been more vertical down to the inferior margin. The preserved bone just below the region of LI1 and C is smooth and almost flat, suggesting that the symphysis was probably broad. The lower L P l has small, somewhat peripherally placed protoconid and metaconid lying opposite one another; they are connected by a thin crest. A thin paracristid runs some distance mesially from the protoconid, then runs back to the metaconid, enclosing a relatively large and deep basin. There is a small entoconid far back at the base of the metaconid, from which it is separated by a small notch. A moderately thick and apparently crenulated cristid runs lingually from the entoconid, up around to the protoconid, enclosing a deep and moderately large basin. The very worn Ldm2 does not preserve much morphology, but there was apparently a flat area or fovea between the entoconid and the hypoconulid. M 1 - M 3 are somewhat elongate teeth, although not very narrow b/1, with rounded distal ends. T h e somewhat worn M i s are rounded, and apparently had bulbous cusps. There is a prominent but low ledge mesially between the protoconid and the metaconid, which bears a small metastylid. T h e base of the blundy wedgelike hypoconid extends slightly across the midline, making broader contact with the small, internally truncated, slightly distally placed entoconid and the m/d elongate metaconid. There is a relatively large, d/1 oriented fovea/basin between the entoconid and the moderate and buccally placed hypoconulid. The buccal cusps are somewhat more internally placed than the lingual cusps. There is a fairly deep, wedgeshaped notch between the protoconid and hypoconid, and a moderate notch between the hypoconid and buccally situated hypoconulid, whose short, tapering base contacts the distal side of the entoconid. T h e

KUAN'S

391

enamel of the slightly worn M 2 and the unworn M 3 is quite crenulated (as it also probably was on M l ) , especially in the long, fairly open talonid basin. Like the M l , the buccal cusps are more bulbous and their apices more internally placed than the lingual cusps. O n M 2 , a thin paracristid courses a short distance mesially from the protoconid, where it turns relatively sharply lingually. It then runs back to the metaconid, enclosing a moderate basin. There is a small metastylid. A small distal basin lies between the small, buccally placed hypoconulid and the slightly distally placed entoconid. The configurations and contacts of the talonid cusps are the same as in M l . There is a deep but narrow notch with a tiny cingulid at its base between the protoconid and hypoconid, and an m/d shorter but deep notch between the hypoconid and hypoconulid. The M 3 cusps are small, low, somewhat compressed, and essentially form a cresdike rim around the large and moderately deep talonid basin. There is a relatively large, flat paracristid mesially between the protoconid and metaconid. Crenulation dominates the occlusal surface. Buccally there is an s/i tall crease between the protoconid and hypoconid and a tall ledge between the buccally placed hypoconulid and the distally placed entoconid.

SK 6 Lower Dental Morph (includes SK 10,12,23, 25,74a, 100 as well as SK 15,843, and 846a (volume 2)) Since the M 1 - M 2 of the SK 6 lower dental morph are generally similar to those of the TM1517b and D N H 7 / 8 morphs, with the primary features of this morph being found in P2 and M 3 , the M 1 - M 2 will be described in detail only for SK 6. SK 6. T h e holotype of Paranthropus crassidens. It consists of a L corpus and partial ramus with P 1 - M 3 , plus two isolated teeth and two teeth in a bone fragment, making up R P 2 - M 3 . LM3 is still erupting. T h e very b/1 exaggerated RP2 is clearly pathological in shape and morphology. On the other hand, L P 1 - P 2 appear unusually small for any South African early hominid; the morphology of PI seems a bit odd, but that of P2 mirrors the P2s of appropriate specimens in this and other morphs. The corpus is quite tall s/i anteriorly, but shallows posteriorly. It is moderately thick m/1 and tapers moderately infcriorly. There is no mylohyoid line and at best a shallow submandibular depression. Part of the posterior symphysis is preserved, suggesting that the

•fT^^ffci

392

SITE

postincisal plane was long and gently sloping, with a short vertical descent to small twinned genial pits that lie above a tall but not very- posteriorly projecting inferior transverse torus. T h e ramus probably took origin behind M 2 . T h e L P l and more so M l are somewhat worn; P2 and M 2 - M 3 minimally. P i is skewed in the jaw. It is longer m/d buccally than lingually. O n the mesial side of the protoconid is a modest fovea, behind which a crest runs from the base of the protoconid lingually around the rear of the tooth and up the distal side, enclosing a deep basin. There is no metaconid. O n the buccal surface the enamel is distended near the neck. T h e P2 is much longer m/d buccally than lingually, and not as wide b/1 as the M l . A stout crest runs out and around from the mesial side of the protoconid to its distal side, and is separated from the cusp by a crease. This thick crest is indented in the midline of the buccal side. M l and M 2 are subequal in length m/d, and M 3 is slightly longer. The Ms increase slightly in b/1 width from M l to M 3 . T h e worn M l was probably originally similar to the less worn M 2 and M 3 , with very bulbous buccal cusps and sloping sides that constrict the occlusal surface and the long talonid basin. There is some internal wrinkling, especially on M 3 . O n all Ms, there is evidence of an m/d thick paracristid that is limited to the region between the bases of the metaconid and protoconid. O n M l , the metaconid is m/d elongate and the protoconid is relatively m/d shorter, on M 2 - M 3 these cusps are of equal size and length. The M l hypoconid is wedge-shaped and extends somewhat beyond the midline of the crown to make equal and moderate contact with both the metaconid and somewhat internally truncated entoconid. O n M 2 - M 3 , the m/d longer hypoconid is squared off and has a broad contact (across the midline of the crown) with the truncated entoconid. O n M 1 - M 3 the relatively large and b/1 wide hvpoconulid extends more buccally than lingually. M2 bears a distinct metastylid, as may also M l . The M 3 enamel is somewhat crenulated, which suggests that the other Ms would also have been. The grooves between the cusps on the RM1 and on all M 2 - M 3 s are better preserved and are quite deep and fissure-like, and they course in a sinuous fashion just lingual to the midline of the crown, from paracristid to hvpoconulid. SK 10 (attached to SK 164S). Very crushed partial mandible lacking both rami and most of the anterior

ENTRIES

portion. Has damaged L M 1 - M 3 and R M l , as ivdl as worn R M 2 . O n the L the anterior root of th ramus originates just behind M l and curves strongly; it would have obscured M 3 . T h e mandibular guner was probably moderately developed. The teeth were quite large; too damaged to describe, but the LP2 was clearly very large relative to the M l . SK 12. Consists of an essentially edentulous lower face plus some teeth and a mandible with partial alveoli for L through RC and broken and heavily worn crowns of cheek teeth. The lower face is discussed with the SK 48 facial morph. T h e mandibular corpora are quite robust m/1, but are not notably tall s/i. T h e corpus becomes shallower s/i posteriorly. There is some crushing at the front of the jaw, so originally the tooth rows may have been more parallel than they appear now. O n the L the postincisal plane looks tairly well preserved; it is high, moderately long and only gently sloping, and it terminates along a superior transverse torus that is bulkier than the bone below. In the latter area the genial morphologv is unreadable, but there is no pronounced inferior transverse torus. There is no sign of a mylohyoid line, but on both sides there is an anteriorly restricted and shallow submandibular fossa. A large mental foramen is preserved on the L, below P2. The bone below the mental foramen from the region between P i and M 1 - M 2 is flattened and obliquely oriented down and back. T h e anterior root of the ramus begins far forward, below M 1 - M 2 , and thickens the corpus laterally, creating an expansive gutter between the posterior molars and the ramus. The anterior margin of the ramus apparently sloped noticeably backward at its base, only partially obscuring the M3. From what is preserved on the L, the thick alveolar crest bifurcates well above the level of the tooth row into a broad but low posterior crest running toward the condyle, and a thinner but better defined anterior crest running toward the region of the missing coronoid process. Also on the L, an upwardly and backwardly pointing and moderately large mandibular foramen lies below the juncture of the crests. Roots of the lower anterior teeth were slender ano short; crowns were presumably small. P i s and probata P2s are three rooted, and, judging from both sides, tlu P2s were large relative to the M l . T h e Ms are toworn for comment, but in general their shape seencompatible with SK 6 and others of the morph. l h ' M3s are more severely tapering distally even than i

SWARTKHANS

SK 23. SK 23. More or less complete mandible, laterally compressed, with all teeth, quite worn. Large but not massive corpora and rami. Corpus deepest s/i at symphysis, shallowing slightly posteriorly, and thinning to inferior margin. Symphysis is crushed; on the less distorted R side there is a smooth curve from side to side, and a relatively straight profile. Even without crushing, this region would not have been very broad. There is a moderately long, quite sloping postincisal plane that lies high up, with a vertical plane below it descending to a thick transverse torus at the bottom. The genial area is uninterpretablc. Mylohyoid lines are not discernible, and on the R side there is a shallow and on the L a very shallow mandibular fossa below M 1 - M 2 . The region of the digastric fossae is uninterpretablc. Mental foramina arc large on R, smaller on L; both lie below P2. The anterior roots of the very tall rami take origin below M2, where they swell the corpora somewhat laterally. The anterior margins of the rami rise almost vertically, obscuring the M 3 from the side. O n both sides there is a well-developed gutter between the M 3 and the ramus. Behind the M3s the internal alveolar crest rises sharply and thickly to bifurcate well above the level of the tooth row into an anterior crest that runs toward the anterior margin of the ramus below the coronoid process, and a posterior crest that arcs back toward the condyle. T h e coronoid process is tall and rounded, and quite long a/p. It rises noticeably above the level of the condyle, from which it is separated by a narrow and deep sigmoid notch whose crest runs to the lateral margin of the condyle. T h e condyles are moderately broad m/1, but are not very thick a/p, with a relatively straight profile from the rear, and a rather flattish posterior surface. Aside from the crests, the ramus itself is quite thin-boned, with sharp edges all around. T h e gonial regions arc somewhat internally inflected, and do not bear noticeable muscle scarring either externally or internally, apart from a slight thickening low down in the pterygoid region internally. T h e mandibular foramina lie behind and essentially level with the bifurcation of the internal crests. They seem to be relatively small, and face up and slightly back. The teeth are all worn flat, and the dentition was probably originally higher crowned than it currently a Ppears. All six anterior teeth are quite small, the Cs n ot being much longer m/d than the I2s. All Is are

393

shallowly concave lingually and arc fan-shaped. The distal margins of the Cs were much longer than the mesial, and as in the Ps the buccal enamel was somewhat swollen. As best seen on the R, the C bears a strong vertical pillar lingually that terminates in a small swelling. PI is noticeably smaller than P2; it is distended d/1. There may have been a mcsially placed mctaconid, or perhaps just a thickened cristid that runs d/1 and then turns sharply up along the distal side of the tooth. The buccal side is longer m/d than the lingual, and is smoothly and broadly curved m/d, whereas the lingual side is more tightly rounded and shorter m/d. In occlusal outline the P2s are the reverse of the P i s ; they arc longer m/d lingually than buccally, and arc more tightly curved buccally than lingually. The LP2 has an extra cusp lingually, and a crest runs between the protoconid and this accessory cusp. The RP2 is distended distolingually, and may have borne a mctaconid opposite the mcsially placed protoconid or (more probably, as in SK 6) just a crest swinging around the back of the tooth. M 1 - M 2 appear to be subequal in m/d length and b/1 width, and the M3s are slightly longer m/d and narrower b/1. The now-worn anterior molars probably resembled the M 3 s in having bulbous lingual and very bulbous buccal cusps that create a long, narrow talonid basin running almost the length of the tooth, a pit in the region of the mctastylid and some wrinkling internally. The lingual and especially buccal sides of the M 3 slope inward, so that the occlusal surface and the central basin arc quite narrow (thus giving, as the cusps wear away, the impression of a broad, flat occlusal surface). The relatively small M 3 hypoconulid is somewhat centrally placed, with a bit more buccal than lingual extension. O n M 1 - M 2 it appears that the hypoconulid is somewhat buccally placed and its base is oriented m/1, making a small contact with the internally truncated entoconid; also a small conulid appears to lie between these two cusps. SK 25. Crushed juvenile jaw lacking rami and with R and LP2s erupting, unworn R and L M 1 - M 2 , and M3s not fully erupted. Corpora are Very shallow and arc rather thin m/1 in proportion to teeth. There is no discernible mylohyoid line or submandibular depression. The preserved part of R ramus is very thin. All teeth arc bulbous on their sides, and somewhat but deeply wrinkled. The P2s have a distinct mctaconid that lies opposite the mcsially placed and

394

SITE

subcqual protoconid; the two are connected at their bases by a cristid that faces on a fairly large anterior fovea that is bounded by a thick paracristid. The talonid basin is quite large. There is a small but distinct entoconid; from this a thick cristid courses buccally to the distal side of the base of the protoconid, from which it is separated by a slight crease. This tooth appears large relative to the M l . M 2 is noticeably larger b/1 and especially m/d than M l , but in both the buccal side is swollen, and the cusps are internally placed, thereby constricting the long talonid basin. M 1 - M 2 have a distinct pit and cingulid low down in the mctastylid region, a distinct anterior fovea behind the m/d thick paracristid between the mesial two cusps, and a cuspulid intervening between the entoconid and the buccally shifted hypoconulid; also their metaconids are elongate m/d and thus larger than the protoconids. The base of the hypoconid extends across the midline; it is wedge-shaped on M l (with moderate but equal metaconid and entoconid contacts) and squared off and m/d long on M2 (with a broad entoconid contact). Buccally there is a small pit at the base of the juncture between the hypoconid and hypoconulid. On both Ms the hypoconulid is buccally placed and its base angled in and forward; on M l it makes a somewhat broad contact with the entoconid, but on M2 this contact is very slight. A large, centrally placed conulid intervenes between these two cusps. SK 74. Partial mandible (a), with broken teeth and tooth roots, plus two isolated teeth (b: RIj, and c. RP2). Although the association may be tenuous, there is no reason not to discuss these teeth together here. /. SK 74a. A corpus with its inferior part missing and its L side partially sheared off. This is a small but stout jaw that was originally probably quite tall. The dental arcade is narrow and U-shaped. In profile the symphyseal region appears to be indented below the incisor roots, with a bulge inferiorly; whether it has been distorted may be debated. Internally, there is a vertical drop-off below the Is, then a fairly steep and somewhat concave slope that terminates above a very shallow genial "pit" that lacks tubercles. The corpora are thick from side to side, especially posteriorly. The I roots arc compressed m/d and quite elongate s/i, and arc about as elongate as the stouter but m/d compressed C roots. The Cs lie fairly far to the sides. The RPl is smaller in all dimensions than P2, and its occlusal outline is distended d/1 by what probably was a thickened cristid coursing around the talonid basin. The Pi is narrower

E N T R IES

m/d and more tightly curved lingually than buccally, whereas the P2 is slightly narrower and a bit more tightly curved around its centrally placed protoconid. Pi had a small anterior fovea. The RP2 probably had a large metaconid that squared up the m/1 portion of the tooth, as well as a modest entoconid behind, distending the d/1 corner of the tooth. A very thick postcingulid terminated in a swelling on the distal side of the protoconid; there was a less thick mesial cristid that terminated on this side of the protoconid. P2 appears somewhat large relative to the M l . The M l crown is very damaged, its roots bifurcating near the neck. The crown was probably large, perhaps subcqual to that of M2. The crown of the tooth in the position of the M2 crown is very worn; in occlusal outline it is roundedly broad and it tapers distally, thereby looking like an M3 (as in SK 12). There is no evidence that there ever was a tooth behind this one. 2. SK 74b. Slightly worn RI1? with a very compressed root that probably was quite long before being broken. T h e crown is quite slender m/d, and its lingual surface is quite concave in profile. 3. SK 74c. RP 2 , crown worn and damaged. Two of the three divergent roots are broken. In occlusal outline the lingual side of the tooth is slightly longer m/d and more rounded than the buccal side. There apparently was a stout crest running along the distal side of the tooth. SK 100. A RPj, essentially a mirror image of the LP1 in SK 6. TM1517b Lower Dental Morph (includes SK 34, SI, 857, 876,1587 a and b, and 158S and SKW5) In contrast to the SK 6 morph, the M 3 of this morph is blunter distally, with a more open (less centrally furrowed) talonid basin and a buccal hypoconulid, with a cuspulid between it and the entoconid. On less worn molars there is often some cingulid development at least distally (if not more extensively) low down on the buccal side of the protoconid. The PI is small relative to the P2, which is not as large relative to the M l . The P2 is also more rounded buccally, and its postcingulid and posterior fovea arc more noticeably emphasized than their mesial counterparts. Although lacking anterior teeth, SKVV 5 preserves well details o( cheek-tooth morphology and is used here as the cxamplarof the morph. SKW5. Mandible lacking R and most of L ramus, and with R P 1 - M 3 and L P 2 - M 3 (Ml missinc

SWARTKRANS

mesial portion); the M3s are either impacted or still erupting. PI is quite worn, P 2 - M 1 are somewhat worn and M2 is modestly worn. Robust but not excessively massive mandible. There is a smooth backward curve to the symphysis externally; internally there is a short postincisal plane that slopes back, then descends to a large and deep genial pit with a slight transverse torus below it. The symphysis shows a tight curve in outline seen from above and below. Internally there is no sign of mylohyoid lines, but there is a marked submandibular depression running forward from below M2. Digastric fossae are negligible. The anterior root of the ramus starts to bulge out below M l , and greatly thickens the corpus posteriorly. A strong upward curve obscures most of the M 3 , with a moderate gutter between the molars and the ramus. Rami would have been tall and heavily builr, the preserved L gonial region is very thick and bears a swelling of the bone internally in the region of the superior medial pterygoid tubercle. The gonial angle is rounded, but the posterior border of the ramus rises quite vertically. The internal alveolar crest thickens adjacent to M 3 and runs back and up as a stout structure that broadens into a fan-shaped thickening above the level of the tooth row. The upwardly and slightly posteriorly pointing mandibular foramen is smallish and slightly compressed. The anterior teeth alveoli are obscured, but occupied a small tightly curving space at the front of the jaw, with almost straight and slightly divergent tooth rows behind. PI is relatively small, but P2 is much larger, especially m/d. P2 is subsquare but slightly wider b/1 than long m/d, while P I is truncated obliquely lingually. Otherwise, P I appears to be a morphological miniature of P2. O n both Ps, the protoconid is quite mesially placed, and the mctaconid even more so. On P2 there appears to be a moderate entoconid in the d/1 corner, from which a very thick cristid runs to the distal side of the protoconid, from which it is separated by a crease. The distal part of the P i may have been similar to the P2. There is a thin buccal crease on the distal side of the P I protoconid, and on the P2 evidence of a b/1 narrow but m/d thick cristid coursing along the mesial sides of the protoconid and metaconid, enclosing a very small fovea. The Ms increase in size, especially m/d, from M l to M3. All three Ms have a well-defined anterior fovea, hypoconids that cross the midline and a small cuspulid between the entoconid and the mostly buccally placed hypoconulid, which is b/1 broad and twinned

395

on M3, and which on M 2 - M 3 has a small contact with the entoconid. The M l hypoconid is wedgeshaped with equal metaconid and entoconid contacts, while it is longer m/d and more squared off on M 2 - M 3 , with greater entoconid contact. The metaconid is m/d elongate and the entoconid internally truncated on all Ms. M i s have a foramen caecum-like pit between the metaconid and hypoconid, which is expressed as a deeper groove with attendant cingulid on M2 and M 3 . M 3 enamel is slightly wrinked, and there is a wedge-shaped metastylid between the metaconid and the entoconid. As seen on M 2 - M 3 , the cusps arc quite bulbous, especially the buccal ones, which have bulging sides. Unassignable to Morph SAT IS. SK ISiiy identified as LP t . Very worn. Buccally the crown is swollen over the root, and in profile it would have sloped strongly inward. The d/1 corner is distended, giving the occlusal outline a subtriangular shape. On the roots there is a deep vertical lingual groove; mesial to the groove the root is less wide b/1 than it is distally. SK 1S& consists of two fragments, not necessarily from the same tooth. Both fragments are very worn; the larger could have been from an upper P. SAT 27. Isolated teeth. The upper LC is unworn, and huge. It is tall-crowned and bulky at its base, with a long mesial and slightly longer distal Q^C. This latter cdee terminates in a small stvlelikc swelling, from which a modest crest descends on the lingual side. On the mesial side there is a shorter lingual crest, and internal to both crests there is a shallow pit. The unworn LP 1 or P 2 has been partially reconstructed. This P is massive. The paracolic and protocone arc internally placed and separated by a V-shaped groove. Their internal surfaces arc deeply wrinkled. The thick preprotocrista swings mesially before coming back to the paracolic; the postprotocrista is straighten The paracolic bears small styles on either side. SK 45. Fragment of a small R ramus containing M 1 - M 2 and alveolus of M3. At the level of M l the corpus is moderately tall, but it is not very wide from side to side. A moderate to large mental foramen lies underneath the anterior root of M l . Beneath the posterior root of M l the height of the corpus diminishes dramatically, creating a "corner" below M l

396

SITE

and a straight upwardly oriented inferior margin posteriorly. T h e anterior root of the ramus is partially preserved, and lies under the M 3 alveolus. There was no gutter between the M 3 alveolus and the ramus. There is a hint of a mylohyoid groove posteriorly, under the region of the M 3 alveolus. Below this is a well-defined fossa, twinned with another depression anterior to it. M l —M2 are extremely worn, but would not have been very large, and are quite short m/d. O n both teeth the root divides quite close to the neck. The M 3 was probably smaller than M 2 . M2 was probably wider b/1 across the protoconid-mctaconid region than across the cntoconid-hypoconid region. Very different from SK 15. SK 54. Thin-boned partial juvenile calotte, warped and distorted, and pierced by leopard canines. Quite large for a juvenile. Not a juvenile SK 48. T h e three major sutures are preserved. T h e lambdoid is finely interdigitated and not segmented; coronal is not interdigitated or segmented. T h e sagittal is segmented, with a short interdigitated section near lambda, a longer wavy segment more anteriorly, and an even longer interdigitated section running to bregma. The lambdoid suture is low and almost horizontal, and curves across lambda. T h e low occipital plane bears a moderately large, deep and rugose but unpitted suprainiac depression in the midline. The junction between nuchal and occipital planes is rounded; there is slight bunning starting just anterior to the lambdoid suture. Anteriorly a bit of superior orbital margin is preserved on the R. There is a small supraorbital foramen above the midline of the orbit. There is a sharp edge to the superior orbital margin, at least laterally, and the frontal rises directly and steeply from it, with some apparent doming behind. The frontal was quite narrow from side to side, and the L temporal line ran low along the frontal. On the R the squamosal suture is partly preserved, and it appears that the squamous was low, with a shallow and oblique parietal notch. The parietals are short m/1, so the skull would have been very tall, with a flatfish top. Internally, there is a very long frontal crest, and the frontal lobes extended all the way over the orbital cone. The specimen also includes an isolated fragment that is hard to identify, but may be from around the foramen magnum. SK SO. Tooth fragments, heavily worn. Also a condylar portion listed and described with SK 847.

ENTRIES

SK S46a. Lower R M l or M2. Quite large, but not huge. Very worn. Very long, b/1 wide roots, each bifid at the tip. Crown quite long, slightly squarcd-ofV distally with the lingual cusps more peripheral than the buccal cusps. There is a thin trigonid groove anteriorly, and the protoconid lies across from the larger mctaconid The large wedge-shaped hypoconid extends linmallv beyond the midline to make equal contact with the m/d elongate mctaconid and truncated cntoconid. The hypoconulid is large and rather centrally placed, being truncated lineually by a marked fovea. Nonhominid SK 27. Unworn Rdm 2 . It is long m/d, with a very strongly posteriorly arcing and thick postcingulum that surrounds a deep talon basin. The somewhat internally and distally placed protocone is small, like the mctacone to which it is connected by a thin crest. T h e paracone is massive. T h e thick and slightly beaded preprotocrista runs strongly mesially before swinging to the apex of the paracone. Internally, the paracone also bears a crcstlikc structure. A thinner postprotocrista courses directly up the internal face of the small metacone, becoming even thinner as it docs so. Also emanating in a buccal direction from the protocone is a distinct protocone fold that terminates in the middle of the talon basin as the base of the metacone. This specimen is morphologically unique in the Swartkrans collection. SK 846. Also a fragment of cranial roof, possibly L parietal with traces of sagittal and lambdoid suture, as well as a low but thick temporal line. Somewhat thickened in the area near the sutures, and thins anteriorly. Temporal lines parallel the sagittal suture. Lacks internal detail except for a deep posterior meningeal groove. Brain case would have been rather small and low. Not necessarily hominid.

REFERENCES Brain, C. K. 1993. Structure and stratigraphy of the Swartkrans Cave in the light of the new excavations. Transvaal Mus. Monogr. 8: 23-34. Brain, C. K. 1958. The Transvaal apc-man-bcaring cave deposits. Transvaal Museum Memoir 11. Pretoria: Transvaal Museum. Brain, C. K. and P. Shipman. 1993. The Swartkrans bone tools. Transvaal Mus. Mo nog. 8: 195-216.

SWART

KRANS

397

Brain, C. K. and A. Sillen. 19S8. Evidence from the Swirtkrans cave for the earliest use of fire. Nature 336: 464-466. Brain, C. K-, E. S. Vrba and J. T. Robinson. 1974. A new hominid innominate bone from Swartkrans. Ann. TransvaalMus. 29:55-66. Brain, C. K- et al. 1970. New finds at the Swartkrans australopithecine site (2 pans). Nature 225: 1112-1119 and 1217-1225. Broom, R- 1949. Another new type of fossil ape-man. Nature 163:57.

Grine, F. E. 2000. Swartkrans. In: E. Delson ct al. (eds.), Encyclopedia of Human Evolution and Prehistory, 2nd cd. New York: Garland Press, pp. 6S1 - 682.

Broom, R. and J. T. Robinson. 1949a. Thumb of the Swartkrans Ape-man. Nature 164: 841-842.

McKee, J. K., J. F.Thackeray and L. R. Berger. 1995. Faunal assemblage seriation of South African Pliocene and Pleistocene fossil deposits. Am. J. Pbys. Anthropol. 96: 235-250.

Broom, R. and J. T. Robinson. 1949b. A new type of fossil man. Nature 164:322-323. Broom, R. and J. T. Robinson. 1950. Man contemporaneous with Swartkrans ape-man. Am. J. Pbys. Anthropol. 8: 151-303. Butzcr, K. W. 1976. Lithostratigraphy of the Swartkrans Formation. S.Afr.J. Sci. 72:136-141. Clark, J. D. 1993. Stone artefact assemblages from Members 1-3, Swartkrans Cave. Transvaal Mus. Monog. 8:167-194. Clark, W. E. Le Gros. 1967. Man-Apes or Ape-Men? New York: Holt, Rinehart and Winston. Clarke, R. J. 1996. The genus Paranthropus: What's in a name? Calif. Acad. Sci. Mem. 21: 93-104. Day, M. H. and J. L. Scheurer. 1973. SKW 14147: a new hominid metacarpal from Swartkrans. / . Hum. Evol. 2: 429-438. Grine, F. E. 1981. Trophic differences between "gracile" and "robust" australopithccines: a scanning electron microscope analysis of occlusal events. S.Afr.J. Sci. 11:203-230. Grine, F. E. 1988. New craniodcntal fossils ofParanthropus from the Swartkrans Formation and their significance in "robust" australopithecinc evolution. In: F. E. Grine (ed.), Evolutionary History of the "Robust" Australopitbecines. New York: Aldine de Gruyter, pp. 223-246. Grine, F. E. 1989. New hominid fossils from the Swartkrans Formation (1979-1986 excavations): craniodcntal specimens.^///./. Pbys. Anthropol. 79:409-449. Grine, F. E. 1993. Description and preliminary analysis of new hominid craniodcntal fossils from the Swartkrans Formation. Transvaal Mus. Monogr. 8: 75-116.

Hollowav, R. L. 2000. Brain. In: E. Delson et al. (eds.). Encyclopedia ofHuman Evolution and Prehistory, 2nd ed. New York: Garland Press, pp. 141 -149. Howell, F. C. 1978. Hominidae. In: V. Maglio and H. B. S. Cooke (eds.), Evolution ofAfrican Mammals. Cambridge, MA: Harvard University Press, pp. 154-248. Mavr, E. 1950. Taxonomic categories in fossil hominids. Cold Spring Harbor Symp. Quant. Biol. 15:109-118.

Robinson, J. T. 1953.Telanthropus and its phylogenetic significance. Am. J. Pbys. Anthropol. 11: 445-501. Robinson, J. T. 1954. The genera and species of the Australopithecinae.^w./ Pbys. Anthropol. 12:181-200. Robinson, J. T. 1956. The dentition of the australopithecinae. Transvaal Mus. Mem. 9:1-179. Robinson, J. T. 1961. The australopithecines and their bearing on the origin of man and of stone tool-making. S.Afr. J. Sci. 5 7 : 3 - 1 3 . S us man, R. L. 19S9. New hominid fossils from the Swartkrans Formation (1979-1986 excavations): postcranial specimens. Am. J. Pbys. Anthropol. 79:451-474. Susman, R. L., D. de Ruiter and C. K. Brain. 2001. Recently identified postcranial remains of Paranthropus and Early Homo from Swartkrans Cave, South Africa./. Hum. Evol. 41:607'-629. Vrba, E. S. 1982. Biostratigraphy and chronology, based particularly on Bovidae, of southern African hominid-associated assemblages. Proc. Cong. Pal. Hum., ler Congres. Nice, CNRS, pp. 707-752. White, T. D. 1976. On a newly associated composite mandible from Swartkrans (Mammalia: Hominidae). Ann. Transvaal Mus. 30: 97-100.

Repository Transvaal Museum (Northern Flagship Institution), PO Box 43, Pretoria 0001, Gautcng, South Africa.

398

SITE ENTRIES

I SWARTKRANS Figure 1. SK 6, R and L partial mandibula

ar corpora (scales = 1 cm).

SWARTKRANS

SWARTKRANS

Figure 2 . SK 11, partial lower face (scales — 1 cm).

399

400

SITE

ENTRIES

SWARTKRANS Figure 3. SK 12, partial lower face and mandible (scales \ 1 cm)

SWARTKRANS

SWARTKRANS Figure 3.

(Continued).

401

402

SITE

SWARTKRANS

ENTRIES

Figure 3.

(Continued).

SWAKTKKANH

SWARTKRANS

Figure 4. SK 13 and 14, partial lower face (scales = 1 cm).

403

SITE

404

ENTRIES

.T^B

^ ^ ^ ^ ^ •

*

Wr^vWt

^^^P§3

^^^p^l

|3?M

^H

fm t MEL *6 a

WmWmM

^H

.•Tj-Vi:

WBMVW

WMtltd H p - JE' " ^fcflr 2 %

SWARTKRANS

, ^

Figure 5. SK 17, partial face (scales = 1 cm).

j j

>i

fff&l ,*m

S W A R T KRJVXS

SWARTKRANS

405

Figure 6. SK 23, incomplete mandible (scales - 1 cm).

Mxtm National d'llistoire Nature u^partement de Pr6histoire 1, ruo Rant Panhard

75013 PARIS

i

40<>

SlTB E N T R I K H

SWARTKRANS

Figure 6.

(Continued).

SwARTKRANS

SWARTKRANS

Figure 7. SK 25, partial mandible (scales - 1 cm).

407

4QH

SITE

SwAR

TKRANS

EXTRIES

Figure 8. SK 27, partial cranium (scale = 1 cm; close-ups ps not to scale).

SWARTKRANS

F i g u « 9 . SK34,incomplete mandible (scales = lcm).

410

SITE

SWARTKRANS

ENTRIES

Figure 10. SK 46, partial cranium (scales p 1 cm; close-up not to scale).

SWARTKRANS

SWARTKRANS

Figure 10. {Continued),

411

412

SITE

ENTRIES

SwARTKRANS Figure 11. SK 47, partial cranium (scales = 1 cm; close-ups not to scale

SWARTKRANS

SWARTKRANS

Figure 1 1 .

{Continued).

413

SITE

414

SWARTKRANS

ENTRIES

Figure 12. SK 48, incomplete cranium (scales = 1 cm; close-up not to scale).

S\VARTKRANS

SWARTKRANS

Figure 12. {Continued).

415

416

SITE ENTRIES

SWARTKRANS

Figure 13. SK 49, incomplete palate (scales = 1 cm).

SWARTKRANS

SWARTKRANS

Figure 14. SK 52, partial face and R braincase (scales = 1 cm).

417

418

SITE

SWARTKRANS

ENTRIES

Figure 14, {Continued),

419

S W A R T KRAKTS

SWARTKRANS

Figure 14.

(Confirmed).

420

S U I T E Es:*in3BDE.»

SWARTKRANS

Figure 15. SK 54, partial braincase with puncture marks (scales - 1 cm).

SWARTKRANS

s Figure 16. SK 55a, partial palate, and SK 55b, partial mandible (icale - 1 cm). Figure

SWARTKRANS

421

422

SITE

ENTRIES

•' .

N|^H wr'&f$*L& SS&M:
SWARTKRANS Figure 17. SK 61, partial juvenile mandible (scales — 1 cm).

SWARTKRANS

SWARTKRANS Figure 18. SK64,juve„ile partial Rmandibular corpus (scales - 1 cm).

423

424

SITE

SWARTKRANS

ENTRIES

Figure 19. SK 65, L anterior face (scales - 1 cm).

SWARTKRANS

SWARTKRANS

Figure 20. SK 74a, partial mandible (scales - lcm).

425

426

S I T E ENTRIES

SWARTKRANS

Figure 21. SK 74b and c, upper premolar and lower incisor (scale =! 1 cm).

SWARTKRANS

SWARTKRANS

Figure 22. SK 79, partial cranium (scales =

427

428

SITE

SWARTKRANS

ENTRIES

Figure 23. SK 81, partial mandible (scale — 1 cm).

SwARTKKAttS

SWARTKRANS

Figure 24. SK 83, partial cranium (scales = 1 cm).

429

k

430

S l T E ENTIUES

SWARTKRANS

Figure 25. SK 858,861 and 883, partial mandible (scales » 1 cm).

INTRODUCTION

SWARTKRANS Figure 26. SK 876, partial mandible (scales = 1 cm).

431

432

SITE ENTRIES

•

i

BY I

SWARTKRANS

-4^*M

1 |Jf

1

Figure 27. SK 1587a, partial L mandibular corpus; 1587b, lower R molar (scale = 1 cm).

SWARTKRANS

Figure 28. SK 1588, partial R mandibular corpus (scale « 1 cm).

SwARTRRANS

SWARTKRANS

433

Figure 29. SK 3978, partial juvenile mandible and unerupted masot crown* (*cafe» • 1 «»»)*

434

SITE ENTRIES

SWARTKRANS

Figure 30. SKW 5, partial mandible (scales = 1 cm; close-up not to scale).

SWARTKRANS

435

... •

IQJlEllin I

Hi

I •

k-1

5^kE 1

HSI

l

! '1

| •

•

•1

SWARTKRANS

Figure 30.

(Continued).

r SITE

436

SWARTKRANS

ENTRIES

Figure 31. SKW 11, partial lower face (scales - 1 cm).

TABARIN

(Tugen Hills)

LOCATION Fossiliferous outcrops in the Baringo Basin of westcentral Kenya, approx. 20 km W N W of the northern tip of Lake Baringo and just to the east of the northern sector of the Tugen Hills, some 2 km north of Rondonin (Map 2).

DISCOVERY Kiptakm Cheboi of the Baringo Palaeontological Research Project, 1984.

MATERIAL R mandibular corpus fragment (KNM-TH 13150), with M 1 - M 2 and partial root of P2.

DATING AND STRATIGRAPHIC CONTEXT Surface find derived from conglomeratic sediments of the Chemeron Formation (Hill, 1985). A maximum age of about 5 Ma is provided by K/Ar dating of a tuff conformably underlying the main fossiliferous horizon from which the mandible is derived (Hill, 1985); since this horizon is immediately superjacent to the tuff, Hill (1985: 222) remarked that "it is reasonable to suppose that the hominid is not appreciably younger than these isotopic dates." This supposition has subsequently been confirmed by Ar/Ar dates, bracketing the hominid-yielding deposits between 4.48 and 4.41 Ma (Deino et al.,2002).

PREVIOUS DESCRIPTIONS AND ANALYSES The mandibular fragment KNM-TH 13150 was described initially by Hill (1985), who remarked that the balance of resemblance lay with Australopithecus afarensis. In subsequent works (e.g., Hill, 2000) the same author also noted similarities to the laterdescribed A. anamensis and Ardipitbecus ramidus. A lost commentators have been content to let this fossil rest as a presumed member of A. afarensis, but Ferguson (1989) has made it the holotype of Homo antiquus praegens, oddly claimed (p. 386) to be "an earlier evolutionary stage** of the former. Most recently, Deino et al. (2000) have returned to the possibility of affinities to Ardipitbecus ramidus, based on the common possession of narrow molars and thin molar enamel.

MORPHOLOGY

KNM-TH 13150. Mandibular fragment containing (probably) M2 (partially missing its enamel) and M3 (missing all enamel). Traces of ramus are beginning to rise behind the posterior tooth. Corpus is thin from side to side, and swells considerably at the root of the ramus laterally, where there is a flat horizontal shelf. In front of the anterior tooth are traces of two lingually positioned roots; in front of these roots are the remains of the alveolus for a very lingual root. The anterior tooth was very small, short m/d, and broad b/1. B/l width across the protoconidmetaconid region was greater than across the

437

4.\S

S I T I-: 10 N T H 1K H

cntoconid-hvpoeonid region. The metaconid was huge; it still projects considerably even though the tooth is very worn. A deep wear facet at the back of the tooth indicates the presence of a centrally placed hvpoconulid. The buccal surface is very bulbous (indicating a marked buccal slope, and internally placed buccal cusps). The second tooth had a very strong buccal slope. Its metaconid is by far the most salient cusp and the trigonid is dominant to the talonid. It is not possible to determine the presence of a contact facet on the distal side of the second tooth. But if the preserved teeth arc M 2 - M 3 , then the M2 is abnormally tiny and there would have been a huge retromolar space behind M3. Also, the preserved alveoli suggest that a huge tooth lay in front of M2. If, instead, the teeth arc M 1 - M 2 , the dental proportions arc consistent with a suid identification (as is the corpus).

TAHARIN

RlCFKRFNCKS Deino, A. ct al. 2002. ^Ar/3'' Ar geochronology and palcomagnetic stratigraphy of the Lukcino and lower Chemcron Formations at Tabarin and Kapchcbcrck, Tugcn I lills, Kenya./ ///////. Evol. 42: 117-140. Ferguson, \V. 1989. Taxonomic status of the hominid mandible KNM-KK TI 13150 [sic] from the Middle Pliocene of Tabarin, in Kenya. Primates 30: 383-387. Mill, A. 1985. Farly hominid from Baringo, Kenya. Nature 315:222-224. I Jill, A. 2000. Baringo Basin/Tugen I lills. In: E. Dclson ct al. (eds.), Encyclopedia of Human Evolution and Prehistory,

2nd cd. New York: Garland Press, pp. 128-130. Repository National Museums of Kenya, PO Box 40658, Nairobi, Kenya.

Figure 1. KNM-TH 13150, mandibular fragment. (Courtesy of Andrew Hill.)

TAUNG

(Taungs)

the result of the predatory activities of eagles nesting in trees overhanging the place of deposition. This notion is further supported by the frequency of eggshell fragments in the deposits and by the nature of damage to the fossils, including the child's skull itself (Berger and Clarke, 1995). One unsuccessful geomorphological dating attempt produced an age of under a million years (which gave rise to suggestions that the Taung child might be the remains of a "robust" australopith); and a preliminary thermoluminescence date on calcite from the tufa was similarly young. However, the latter probably does not date the enclosing tufa itself. Up to now, then, determination of the age of the hominid deposit has been possible only by faunal correlation, and there has been much discussion on this point. Earlier faunal age estimates tended to combine fossils from elsewhere in the site with those from the hominid deposit, and thus were of highly limited precision. Recent faunal seriation focusing on the seven mammal species directly associated with the hominid suggests an age intermediate between the Makapansgat 3 and 4 deposits and those from Sterkfontein Member 4 (McKee, Thackeray and Berger, 1995). An age of around 2.8-2.7 Ma thus looks plausible.

LOCATION Fissure fill in flowstones at the Buxton/Northern Lime Company limeworks, approx. 10 km SW of Taung, Northern Cape, South Africa (Map 4). DISCOVERY M. de Bruyn, 1924 MATERIAL Face, partial endocast, and partial mandible of a juvenile (Taung 1), estimated by Bromage (1985) to have been 3-4 years old at death.

DATING AND STRATIGRAPHIC CONTEXT The hominid was recovered from a pinkish calcified sandy and silty deposit within a tufa, probably at some 15-m depth, though the exact findspot is not recorded (nor could it have been, given that the deposit was being mined using explosives on a large scale). Partridge (1985) has given a general account of the site which, starting in 1919, also produced a large number of nonhuman mammalian (mosdy baboon) fossils. These latter appear to mostly to have come from red sands that occurred lower in the sequence than the Taung child. The fauna in the hominid deposit seems to have been almost exclusively of small-bodied individuals. Among other factors this led Dart (1926) to speculate that the fossil accumulation was due to the action of hominids, but Berger and Clarke (1995) have presented cogent arguments for interpreting this fact as

PREVIOUS DESCRIPTIONS AND ANALYSES In 1925 Raymond Dart made the Taung child the holotypc of the new species Australopithecus africanus, a "man-like ape" that he proposed to place

439

440

SITE

in "the new family of Homo-simiaJaf [sic] (p. 199). Predictably tor the period, reactions were mixed. In their accompanying commentaries, for example, Arthur Keith (1925) emphasized the "anthropoid" characteristics of the Taung child's skull and brain, and (though considering it possible that Australopithecus [sic] might turn out to "be intermediate between living anthropoids and man" (p. 234), preferred to place it "in the same group or subfamily as the chimpanzee or gorilla" (p. 234); Elliot Smith (1925) demanded more evidence as to age and dental morphology; and Smith Woodward (1925) noted "defects in the material for discussion" (p. 235). In the end, it was not until after World War II that Australopithecus became generally accepted as an carlv hominid (sec discussion of this matter by Lc Gros Clark, 1967). Australopithecus africanus is now universally recognized as the classic exemplar of the "gracilc" australopiths. Whether or not the taxon that embraces the rapidly increasing diversity of early hominid bipeds should be recognized as the subfamily Australopithccinac, or at some inferior taxonomic level, is still a subject of debate; but the position of the Taung child is secure as the holotypc of the species Australopithecus africanus, irrespective of what other materials may or may not be included in this species' hypodigm. From the preserved partial endocast, Holloway (2000) has estimated an adult brain volume of 440 ml.

M o R P I lOLOGY Taung Upper and Lower Dental and Facial Morphs Taunt; /. Juvenile face and partial mandible, with stubs of upper and lower deciduous incisors, crowns of upper and lower dc, d m l - d m 2 and M l of both sides. Plus endocast with some adherent bone. Face, In profile, the glabellar region is prominent, rounded and flows smoothly up into the backwardly curving frontal. Also in profile, the inferior orbital plane is rather vertical. Viewed from above, postorbital constriction is minimal and the inferior orbital region curves smoothly around and into the zygomatic arches. A shallow depression lies inferior to the zygomaticomaxillary suture. The orbits are tall, rather ovoid, with thin, slightly projecting lateral margins. The roof of each orbit is quite flat, and angles sharply onto the superior margin laterally, more smoothly medially. The orbital floors were ossified across, at

ENTRIES

least anteriorly. Other orbital detail is obscured. The intcrorbital space is flat across, not very wide, and slightly concave in profile. Nasion lies low, just above midorbit. The nasal bones were apparently much broader interiorly than superiorly. They were probably broken interiorly, so nasal aperture height may have been even lower than it currently appears to be. The nasonasal suture is not discernible beyond twothirds up its length; other apparent sutures around the nasal bones may be partly artifactual, though nasion itself seems reliable. The infraorbital foramen is small, downwardly pointing, with a small sulcus below; it lies moderately close to the inferior orbital margin. O n both sides, a taint pillar rises from the Cs to fade out around the level of the infraorbital foramen. These pillars do not extend into the frontal processes; they lie close to, but do not form the sides of, the nasal aperture. The lateral margins of the nasal aperture arc very rounded. The inferior boundary of the nasal aperture is indented at the midline, lateral to which the inferior nasal margin flows smoothly but tightly up and out onto the lateral margins. For the size of this individual the nasoalvcolar clivus is moderately long; it is somewhat arced across, and curves smoothly out and down. T h e clivus flow's smoothly into the nasal cavity above, where there is a steep but smoothly curving stepping-down into the floor ot the nasal cavity. Small incisive fossae lie well within the nasal cavity. T h e anterior root of the zygomatic arch originates fairly high up, above dm2. The inferior margin of the anterior root rises steeply, both back and away from the infraorbital sulcus. As preserved on the R, the thin zygomatic arch goes almost straight back to bound the m/1 narrow temporal fossa. T h e carotid canal was well ossified anteriorly. Jugular and carotid foramina appear to have been present, but are distorted; apparently they opened into a single vestibule. Most of the occipital condyle and anterior condylar foramen lay on the lateral part of the occipital. The palate is quite shallow anteriorly, deepening somewhat posteriorly; it is tightly curved at the front. Seen from the side, the palate curves up from back to front. T h e incisive foramen is small and narrow, and lies opposite the C - d m l junction. Internally, the orbital cones are raised on cither side of a very deep depression for the cribriform plate. The frontal lobes extend well over the orbital cones. The sphenoid sinuses were quite well developed for an individual this young.

TAUNG

Mandible. The top of the mandibular ramus is adherent to the cranium on the R; it is broad a/p, already quite tall, and fairly vertical. The coronoid process is broad and rounded, and slightly surpasses the condyle. The condyle is broad m/1 and somewhat hooked medially, with a flat, thick posterior surface. The sigmoid notch is somewhat long, quite deep and deepest at its midpoint. The sigmoid notch crest runs to the lateral side of the condyle. The separated lower part of the mandible is missing the inferior margin, but the corpora arc quite substantial. The tooth rows arc tightly curved at front, and are more or less parallel behind. In profile, the front of the jaw is fairly vertical, with only a gentle curve down and back in profile. The postincisal plane is quite long and sloping, with a large, deep genial pit below. Below the genial pit was apparently some kind of torus (the bone protrudes just above the break). As seen on the L, the mental foramen is single; it lies under d m l . T h e ramus originates at M l , and curves up quite strongly. Upper teeth. T h e dils are worn to the pulp cavities. T h e dI2s are less worn, and appear to have had laterally curved crowns that were probably much smaller than those of the d i l s . O n both sides the dc is separated from the dI2 by a modest diastema. In buccal view, the subequal mesial and distal edges of the somewhat worn dc crown diverge rather strongly. Lingually, this tooth bore a mesially placed pillar with a small fovea anterior to it. T h e tip of the dc extends beyond the level of the cheek teeth. T h e d m ' s are very worn, somewhat broken and obliquely truncated m/1. They were smaller b/1 and m/d than the also rather worn drn2s. As seen on the R, the d m l had small mesial style at the terminus of a short preprotocrista; there probably was a larger style at the terminus of the broad postprotocrista. T h e protocone was larger and more central than the mesially shifted paracone. T h e dm 2 s are subsquare, with somewhat sloping lingual sides and straight buccal sides. As better seen on the R, the protocone is somewhat mesially placed and there is a vertical groove between it and the b/1 wide but m/d compressed hypocone, which also does not extend as far lingually as the former cusps. Also on the R, the rather large metacone is somewhat m/d compressed and it appears that a thick postprotocrista coursed up its internal face; this cusp lies close to the slightly larger paracone. Judging from the L d m 2 , the preprotocrista was probably poorly developed. A relatively stout but very short postcingula emerges from the tip

(TAUNGS)

441

of the hypocone and runs to the side of the base of the rather large mctacones, enclosing a small basin. The M i s are tall-crowned, low-cusped and subrectangular, with some wrinkling of the occlusal surface. The buccal and especially the lingual sides of the crown are quite sloping. The M l hypocones are b/1 wide and m/d compressed, with stout postcingula that terminate at the sides of the bases of the relatively large mctacones. On each side, the very broad protocone is slightly mesially placed, with gently sloping lingual and buccal sides. The prcprotocrista is strong and goes straight up the side of the tooth. Lingually, a deep vertical crease with a stylelike structure at its base lies between the hypocone and the protocone. A very thick postprotocrista courses up the internal face of the somewhat m/d compressed metacone; this cusp lies close to the larger paracone. A weak prcprotocrista courses to the mesial side of the paracone. Lower teeth. T h e dis are small and worn to pegs. T h e des are worn and broken; as seen on the L, the distal edge was longer and more sloping than the mesial edge. A margocristid is present lingually. T h e d m l s are worn, damaged and much smaller than the dm2s, which are in turn much smaller than the M i s . Both d m l s are exodaenodont buccally.The mesially tapering trigonid portion of the crown was much longer m/d and taller than the shorter but m/1 wider talonid portion. As seen on the R, there is a noticeable hypoflexid notch between the larger protoconid and the smaller, buccally swollen hypoconid. As seen on the L, there was a stout paracristid going down the mesial face of the protoconid; it may have kinked to the base of the metaconid. T h e trigonid basin is vertical, slightly lingually facing, and formed a notch between the protoconid and the slenderer metaconid. As seen on the R, the entoconid and hypoconid lay opposite each other and there was probably a small cuspulid low down next to the buccal side of the base of the former cusp. T h e dm2s are long m/d and relatively narrow b/1, but are narrower mesially than distally. T h e metaconid is compressed a bit b/1 and is longer m/d than the protoconid. The paracristid is short, with an indication of a basin behind it. This basin is separated from a more distal basin by a crest between the protoconid and the metaconid. T h e entoconid is compressed b/1 and longer m/d than the hypoconid; there seems to have been a broad contact between the bases ot these two cusps in the midline of the crown. T h e hypoconuhd

4

4

2

: •

• • • ; • , - . • .

s ,

T

E

is relatively small, mostly buccally placed, with a small, d/1-orientcd cuspulid wedged between it and the entoconid. It appears that the hypoconulid tapered toward its contact with the base of the entoconid, Buccally, a pit lies between the protoconid and hypoconid, and a notch between the hypoconid and hypoconulid. T h e lingual cusps are peripherally placed; apparently they were once taller than the more internally placed buccal cusps. The M l crowns are m/d long, b/1 narrow, and rounded distally. Both M i s have deeply wrinkled surfaces, a deep pit between the protoconid and hypoconid bases, a notch between the hypoconid and hypoconulid, and a trace of cingulid around the protoconid base. They also have a short, stout paracristid that courses high up between the apices of the protoconid and metaconid and encloses a smallish but somewhat deep trigonid basin; the bases of these two cusps are melded in the midline of the crown and thus give the appearance of a thick crest. The metaconid is long m/d and appears to be confluent with the entoconid, which is long m/d and generally larger than the hypoconid. The wedge-shaped base of the hypoconid extends slightly across the midline of the crown to make a small contact with the metaconid and a broader one with the entoconid. A small conulid lies between the hypoconulid and the entoconid. The smallish, wedge-shaped hypoconulid is centrally placed; its tip contacts the entoconid and the distal end protrudes backward, being distinguished further by a notch between it and the hypoconid and a groove between it and the conulid. The lingual cusps (especially the metaconid) are rather peripherally placed and slightly taller than the more internally placed buccal cusps.

REFERENCES Berger, L R. and R. J. Clarke. 1995. Eagle involvement i n accumulation of the Taung child fauna./ Hum Evol 29 275-299. ' Bromage, T. 1985. Taung facial remodeling: a growth and development study. In: P. V.Tobias (cd.), HominidEvolution: Past, Present and Future. New York: Alan R. Liss pp. 119-134. Clark, W. E. Le Gros. 1967. Man-Apes or Ape-Men} New York: Holt, Rinchart and Winston. Dart, R. A. 1925. Australopithecus africanur. the Man-Ape of South Africa. Nature 115:195-199. Dart, R. A. 1926. Taungs and its significance. Nat. Hist. 26: 315-327. Holloway, R. 2000. Brain. In: E. Dclson ct aL (eds.): Encyclopedia of Human Evolution and Prehistory, 2nd ed. New York, Garland Publishing, pp. 141-149. Keith, A- S. 1925. The fossil anthropoid apefromTaungs. Nature 115:234-235. McKee, J. K. 1995. Faunal assemblage seriation of southern African Pliocene and Pleistocene fossil deposits. Am. J. Phys.Anthropol. 96:235-250. Partridge, T. C. 1985. Spring flow and tufa accretion at Taung. In: P. V. Tobias (ed.), Hominid Evolution: Past, Present and Future. New York: Alan R. Liss, pp. 119-134. Smith, G. E. 1925. The fossil anthropoid apefromTaungs. Nature 115:235. Woodward, A- S. 1925. The fossil anthropoid ape from Taungs. Nature 115:235-236. Repository Department of Anatomy and Human Biology, University of the Witwatersrand Medical School, York Road, Parktown, Johannesburg 2193, South Africa.

TAUNG ( T A U N G S )

TAUNG

Figure 1. Taung 1. Skull, face and natural endocast ofjuvenile (scales = 1 cm).

443

444

SITE

TAUNG

ENTRIES

Figure 2. Taung 1. Face and upper dentition ofjuvenile (scales — 1 cm).

TAUNG

TAUNG

(TAUNGS)

Figure 2.

(Continued).

445

446

SITE

TAUNG

ENTRIES

Figure 3. Taung 1. Partial mandible and lower dentition ofjuvenile (scales = 1 cm).

TAUNG

TAUNG

(TAUNGS)

Figure 3.

(Continued).

447

(Lomekwi, Lokalalei, Nachukui)

TURKANA, W E S T

Tuff D, at about 2.45 Ma. The W T 17400 partial cranium is said by Feibel et al. (1989) to come from Kaitio Member, which would place it at about 1.77 Ma. The isolated molar W T 17396 is from the site of Kokiselei I (Leakey and Walker, 1988). This is said to lie stratigraphically between the Malbe and Okote Tuffs, which would make it of about the same age.

LOCATION Fossil collecting area to the west of Lake Turkana, northern Kenya (Map 2). Two specific non-Homo hominid localities (Lomekwi I and Kangatukuseo III) were described by Walker et al. (1988), respectively, in the Lomekwi and Kangatukuseo ephemeral drainages, approx. 15 km north of the village of Kataboi. See Harris et al. (1988) for other localities.

ARCHAEOLOGICAL CONTEXT Oldowan archaeological assemblages have been found at various levels within the Nachukui Fm (Kibunjia et al., 1992; Kibunjia, 1994; Roche et al., 1999). Earlier assemblages (2.35 Ma) are said to be "less refined" than later ones (1.8 Ma) (Kibunjia et al., 1992), but refitting studies have impressed Roche et al. (1999) with the cognitive and technological capacities of stone knappers at ca. 2.35 Ma. There is no evidence to link any Nachukui stone tools with any specific kind of early hominid.

DISCOVERY 1985, by a survey team led by R. Leakey and A. Walker. MATERIAL The cranium KNM-WT 17000 and partial mandible W T 16005; the anterior cranium \VT 17400; and an isolated molar tooth.

DATING AND STRATIGRAPHIC CONTEXT By geochemical correlation of tuffs with the corresponding Ethiopian Shungura Formation sequence of fluviolacustrine sediments interspersed with datable volcanics, the West Turkana australopith-yielding sediments of the Nachukui Formation have been dated with some precision (Walker et al., 1986; Harris et al., 1988). The Lomekwi I locality from which the W T 17000 cranium was recovered lies just below an ashfall corresponding to Shungura Tuff D, and is dated to 2.50 Ma. The Kangatukuseo III site that yielded the W T 16005 mandible lies just above the equivalent of

PREVIOUS DESCRIPTIONS AND ANALYSES Nachukui australopith fossils have been described by Walker et al. (1986) and Leakey and Walker (1988), who referred them all to Australopithecus boisei. However, they did note the possibility that the W T 17000 cranium might be shown to belong to a separate species, antecedent to A. boisei. Should this occur, they suggested that this specimen be transferred to the species Australopithecus aethiopicust based on the penecontemporancous Omo 18-1967-18 mandible

448

TintKANA, W E S T

(LOMEKWI,

that had been made the holotypc of Paraustrahpithecus aethiopicus by Arambourg and Coppcns (1967). At the wry least, these authors noted, the new specimens demonstrated that the V . boisei lineage was established at least 2.5 Myr ago" (Walker et al., 1986); and they further suggested that in various calvarial characters they regarded as primitive, the West Turkana form resembled Australopithecus afarensh but not A. robustus. As a result they favored the view that an evolving A. boisei lineage, independent of that leading to A. robustus, could be discerned in eastern Africa in the 2 . 5 - 1 . 5 M a time range. This lineage, they claimed, showed a time-dependent increase in cranial capacity and various other cranial features, some of which paralleled developments in the Homo lineage that had occurred over more or less the same period (Leakey and Walker, 1988). The notion that P. boisei does not constitute a distinctive species, but is rather nothing more than an ephemeral segment of a gradually transforming lineage, seems not to have appealed to others with the exception of Suwa (1988) and his collaborators. Instead, most subsequent commentators have followed Kimbel, W h i t e and Johanson (1988) in accepting W T 17000 as solid evidence of the distinctiveness of the species Australopithecus (or, increasingly, Paranthropus) aethiopicus—which varies, moreover, at least as much as does P. boisei or A. afarensis (Kimbel, W h i t e and Johanson, 1988). Ferguson (1989) has made W T 17000 the type of the new species P. walkeri, and this name is available should it be found necessary to dissociate the West Turkana cranium from the undiagnostic (but clearly different) aethiopicus holotype mandible O m o 18—1967-18. Nomenclature aside, W T 17000 is generally taken as evidence of the relatively ancient existence of a "robust" australopith lineage, even though in the wake of its discovery questions have been raised as to the monophyly of the enlarged "robust" clade (e.g., Wood, 1988). A variety of phylogenetic schemes into which W T 17000 might potentially fit were presented by Delson (1987, following F. Grine). Holloway (2000) quotes an endocranial volume for the W T 17000 cranium of 410 ml.

MORPHOLOGY

LOKALALEI,

NACIIUKUI)

449

elsewhere. All specimens are individually described, but arc grouped into morphs or listed as unassignable. Cranial specimens are described first, followed by mandibular ones. K N M - W T 17000 Cranial Morph [includes KNMER 405 and possibly KNM-BC 1 (volume 2)] KNM-WT 17000. Cranium reconstructed from numerous pieces, some badly eroded, and lacking most of the cranial vault, part of the basicranium, parts of the zygomatic arches and lateral orbital regions, all teeth and nasal cavity structures. The cranial bone is very thin indeed. The face is haftcd to the ncurocranium very far forward, so that it is positioned in front of the frontal lobes, with a pronounced postorbital constriction. The postorbital plate is thus very extensive, and the lateral magins of the orbit project very far from the ncurocranium. The central part of the cranial vault is missing, but the side profile of the frontal behind the orbits rises gently, and would have been exaggerated by a tall and thick sagittal crest whose greatest elevation, preserved posteriorly, lay well above the junction with the nuchal crest. Seen from behind, the ncurocranium curves out on cither side of the sagittal crest to flow into a broad shelf that encircles its base; this shelf is a continuous structure composed of the projecting nuchal crest, the supramastoid bulge, and the posterior root of the zygomatic arch. Below the nuchal crest, the very flat nuchal plane forms a sharp angle with the more curving occipital plane. Seen from above, the supraorbital region contacts the ncurocranium only centrally, at which point the one flows into the other without forming a torus that projects cither anteriorly or superiorly. Also from above, the orbital margin is relatively straight across, with glabella protruding somewhat in the center. A distinct frontal trieon is formed by well-marked temporal lines that originate on the upper margins of the orbits and run quite medially before turning back to converge well anterior to bregma. There is a small circular depressed fracture posterior to the R temporal line at the orbita midpoint, with bone adhering. Wontal sinuses as ob J b l e through a; break on the rights, e, a , v ry

#

In the small sample of non-Homo hominid fossils from the various West Turkana localities we recognize several distinct cranial and mandibulodcntal morphs, at least one of which is represented at localities

asw/—>==**

450

SfTE

while flatfish, is positioned slightly in front of the supraorbital margins. The face has been extensively reconstructed, and there are inconsistencies other than those noted below. For instance, in the L orbit a fragment incorporated into the inferior margin of the orbit bears a good portion of the anterior lacrimal crest, which in this reconstruction is oriented obliquely rather than vertically. Also, this sharp-edged piece of bone is made to join with an adjacent piece bearing a much more rounded edge. Rotating the lacrimal crest into a more normal vertical position would not only restore a more plausible morphology of the orbital rim, but would also modify the lateral nasal margin and contribute to making the face more orthal.Thus at present it is impossible to describe either the orientations of all the components of the face or the shapes of the spaces these components define, e.g., the orbits and nasal aperture. Because of this, only regional morphology will be reported here. The bodies of the zygomas are very deep and broad and were probably originally forwardly facing, although more vertically oriented than in the reconstruction. The anterior surface of the zygoma is bowed out, almost in parallel with the very concave posterior surface that contributes to the temporal fossa. As preserved on the L, there are two moderately sized zygomaticofacial foramina. T h e attachment for the masseter forms a well-defined and anteriorly expanding sulcus on the underside of the zygoma. The interorbital region is not very broad. Neither are the preserved parts of the frontal processes of the maxilla, nor the preserved superior parts of the nasal bones lying between them. As preserved the nasal bones are relatively flat across, and the nasomaxillary sutures are more or less parallel. There is a slight to moderate flexion a bit below nasion. It is impossible to determine how long the nasal bones were, but it seems quite likely that they were quite long and flared-out inferiorly. The lower part of the broadly piriform nasal aperture is rounded at its corners, but these are not flared out. The inferior margin of the nasal cavity flows straight into the nasoalveolar clivus, with no demarcation. T h e vomer reaches quite far forward, and the large incisive fossae are fairly far back. The nasoalveolar clivus is quite long, and gendy curved downwards. At the rear of the nasal cavity a break in the sphenoid reveals a small sinus running anteriorly. If a true sphenoid sinus, this structure would normally be

ENTRIES

much more posterior, adjacent to the hvrvmk c i_ - u * t~ J t ^ r^pnyseal fossa, which is here preserved almost 2 cm beh' A • (although this sinus is obviously not complete). If ru* sinus were rotated back to this position, it would b * the face along with it, producing a much flatter D file. At the same time, it would close the gap that exists between apparendy matching surfaces of the T medial orbital wall and would eliminate other apparent inconsistencies, for example, the gaps between also apparendy matching surfaces in the region of the frontonasal suture and in the lateral wall of the L orbit, the anomalously forward-slanting (rather than downwardly pointing) lacrimal canals, and the upwardly rotated inferior margins of the orbits. It thus appears (as also noted earlier) that the face of \VT 17000 was originally signiflcandy more orthal than as currendy reconstructed. T h e relatively short ectotympanic tube lies in the same oblique plane as the petrosal and terminates medially, level with the small postglenoid plate that lies essentially at the midline of the broad, shallow articular fossa (cf. the Chemeron temporal). The auditor)* meatus is large, anteroposteriorly compressed and slightly anteriorly tilted, and the bone of its circumference is relatively thin. The articular fossa is broad m/1 and shallow and long a/p, without a prominent articular eminence. Laterally, the fossa is open, but it is essentially closed off medially by a low, thick, anteroposteriorly elongate and platelike medial articular tubercle. From the posterior root of the zygomatic arch, across the squamosal and into the alisphenoid, there runs a low, rugose ridge that delineates an infratemporal from the temporal fossa. The bone that bounds the infratemporal fossa lies in an oblique plane. Despite the strong postorbital constriction, the deepest part of the temporal fossa occurs rather posteriorly, opposite the peak of the orbital cone. T h e anterior root of the zygomatic arch takes ongin some distance from the alveolar crest, and probably flared sharply to the side. There is a continuous and laterally expanding ledge that flows from the mastoid region, over the auditory meatus, and into the postenor root of the zygoma. At the point at which this shell reaches the articular fossa its lateral margin arcs steeply upward, presumably having formed a tall, rather honzontally oriented zygomatic arch that is now missing. Toward the rear of the skull, at about the same level and just above the salient nuchal crest, a very large mastoid foramen penetrates the skull vault horizontally. Behind this, the mastoid portion abuts the occipital in a

TUKKANA, W E S T ( L O M K K W I ,

simple sutural configuration, giving no evidence of the presence of a mastoid notch at the rear of the temporal (cf somcytf. afaremis and Chemcron). The nuchal plane is continuous laterally with the flattened mastoid region. Damage to this region exposes extensive pneumatization with small air cells. The short posterior part of the cranial base is largely missing, but the anterior part of the foramen magnum is preserved and suggests a fairly large and broad structure with large occipital condyles quite anteriorly positioned. The basiocciput is broad posteriorly, tapers anteriorly and is essentially flat and smooth. The sphenooccipital synchondrosis is visible just behind a small pharyngeal pit, and the posterior root of the vomer appears to have been placed very far forward of the synchondrosis. The petrosal bears a low, thin vaginal process along its medial portion. On the L side this process appears to peak and envelop the preserved base of a styloid process, which lies rather centrally on the petrosal. Below and just in front of the styloid process is a small, vertically oriented carotid foramen that lies essentially within the jugular foramen. The jugular foramen itself is formed in front by the petrosal and behind by the basiocciput, and is relatively small and is horizontally oriented. It appears that there was originally no foramen lacerum. Just lateral to the styloid process, and very close to it, one can see on the left side a small pit, and posterolateral to that a larger pit or foramen. T h e nature (pit or foramen?) and identification (stylomastoid foramen?) of these structures is uncertain. The basisphenoid flares dramatically laterally at its contact with the basioccipital; it was broad and flat, with a smooth surface. Little remains of the pterygoid plates, but this region was displaced quite far laterally, and on the left are visible the roots of the pterygoid plates. The lateral plate extended further posteriorly than the medial, but the two plates converged toward the rear. A very large foramen ovale is present, part of it lying lateral to, and extending beyond, the pterygoid plates; its medial border is formed by the petrosal rather than being closed off by a sheet of bone. T h e foramen ovale thus lies quite close to the sphenotemporal suture. A small foramen spinosum lies posterior and slightly lateral to the foramen ovale, and appears to be formed in front by part of the temporal and behind by the petrosal (cf. the Chemeron temporal). Internally, the posterior branch of the middle meningeal artery emerges from the junction between

LOKALALBI,

NACIIUKUI)

451

the squamosal and petrosal portions of the temporal, and courses backwards along the length of the petrosal. The superior aspect of the petrosal is very broad from side to side, and stays broad all the way to its peak rather than tapering. Its superior surface bears a slight and anteriorly obliquely oriented elevation corresponding to the superior semicircular canal. There is no sign of a subarcuate fossa or of a superior petrous sinus. However, low down on the wall of the petrosal and right in front of the sigmoid sinus, is a horizontal depression that presumably lies in the region of the inferior semicircular canal (cf. the Chemcron temporal). The clivus of the basiocciput is long and quite vertical, surmounted by a distinct dorsum scllae. The medial cranial fossa is large, but the anterior cranial fossa is extremely small. If the vacuity in the posterior part of the nasal cavity is correctly identified as a sphenoid sinus, then two descending and laminar matrix-filled structures on either side of the midline and in front of the vacuity may represent ethmoidal conchac: an extraordinary phenomenon of preservation. The maxilla is massive and broad from side to side, but the palate itself is narrow. There was very little excavation of the palate, so anterior and lateral slopes were minimal, and the now-eroded alveolar crests would not have descended appreciably below the roof of the palate. The tooth rows, far apart at the front, converged somewhat posteriorly. The rather small single incisive foramen, which lies level with the P2s, opens into a long, horizontal groove anteriorly that runs right to the alveolar margin. On the L is preserved a single, large and somewhat anteriorly oriented greater palatine foramen that emerges level with the distal side of M 3 and is preceded by a large sulcus that runs along the inner wall of the palate. Alveoli, at least partial, exist for the anterior teeth. T h e cheek teeth arc represented by roots. Incisal roots were long but not extremely stout. The C root was similarly long but not robust, penetrating to the corner of the nasal aperture. T h e anterior and posterior premolars were three-rooted; the roots were better separated and more splayed on P2. M l had three roots, the lingual one quite large and the m/b the smallest and most compressed. Buccal roots ot M2 are visible through the bone, and the pulp cavity of this tooth was huge at the level of the root cleft. M 3 roots are similar to those of M l . From their outlines, it is possible to say that all cheek teeth were very large and cspec ially wide, with all three molars of about equal size or increasing slightly posteriorly.

452

S I TE E NTRI ES

In the same box with W T 17000 are two isolated teeth. }430B is a postcrior(?) upper LP crown. Its surface is worn flat, and was probably very thick enamelled. There is a deep fissure between the paraconc and protoconc, and between these cusps and a very thick postcingulum. Buccal and lingual surfaces were somewhat rounded, and it appears that the two cusps are subequal in size. }430A is part of a lower molar crown, possibly LM1 or M2. Its enamel is incredibly thick, and largely unworn except for the protoconid. The hypoconid docs not extend lingually beyond the midline of the tooth, and the hypoconulid is very wide and centrally located. K N M - W T 17400 Cranial and Upper Dental Morph KNM-WT 17400. Partial cranium missing rear and most of basicranium. Superior and lateral orbital regions and zygomas sheared off and l i s missing. M3s just beginning to erupt. The vault bone is not massively thick, but is a little thicker than typical for "robusts." The face is situated anteriorly relative to the ncurocranium. In coronal oudine, the vault is rather triangular, coming almost to a peak in the midline. The supraorbital area is missing, exposing very capacious frontal sinuses that expand laterally beyond the midpoint of the orbits to occupy the entire width of the anterior neurocranium. They also penetrate the frontal at least to the deepest part of the postorbital constriction, and occupy the interorbital region past the nasofrontal suture, at least to the level of the superior part of the lacrimal fossa. The sinuses arc asymmetric, the R being larger than the L, and separated from it by a large, bowed septum. In the orbits themselves shallow lacrimal fossae are preserved on both sides; the anterior lacrimal crests contribute to the inferomedial orbital margin, but are low down and displace the margin slightly forward. On both sides the posterior lacrimal crests lie not only behind but also lateral to the anterior crests, thus orienting the entire lacrimal fossa somewhat forward. Too much of the orbital margins is missing for an accurate assessment of overall orbital shape, but it is reasonable to reconstruct the orbits as originally fairly narrow. The nasal bones were quite narrow, and parallclsided in their preserved parts. They are slightly convex from side to side, but lack a keel and show negligible curvature in side view. Their superior and inferior extremities are missing, and it is impossible to say how

far these bones descended. However, it is clear that they flared laterally below the preserved portion. It ic consequently not possible to determine the original height of the nasal aperture; but if the nasals descended any distance at all, the aperture was fairly restricted in height. Broadly piriform, it is nonetheless quite narrow at its base. The s/i tallncss of the face is also reflected in the height of the narrow internal nasal choanac. In its inferior part the lateral nasal margin is quite rounded, and the vomer came far forward to the edge of the inferior margin, which otherwise appears to have flowed smoothly into the fairly long and quite planar nasoalvcolar clivus (the nasal aperture is blocked by matrix right to the front). In general, the nasal region appears rather sunken in the middle of the face; the zygomatic roots both face and arc somewhat anteriorly from the lateral nasal margin. The infraorbital foramina are quite large and lie well below the inferior orbital margins. They face downward (and laterally on the R), and open into a deep, well-marked gutter on the R, and a shallower one on the L. O n the R a well-marked zygomaticomaxillary suture runs down from the orbit and then obliquely laterally. From the point of inflection another suture runs directly down to the superior margin of the infraorbital foramen. This suture actually represents the prcmaxillary-maxillary suture, and is visible on both

sides. On both sides the anterior roots of the zygomatic arches are broken, exposing huge sinuses internally. Quite evidently, these sinuses proceeded far laterally, and it is possible that the large sinuses behind the nasal bones and frontal processes noted earlier are superior extensions of this same sinus system. The inferior margin of the anterior root of the zygomatic arch takes its origin some distance from the alveolar margin, and appears to have sloped steeply upwards. Behind, it would have delimited an anteriorly oblique temporal fossa. Postorbital constriction was strong. The forehead rises fairly steeply behind where the posttoral region was. The temporal lines apparently originated along the posterior lateral margins of the orbits, and proceeded far medially before turning sharply posteriorly to converge well in front of bregma. On the L there appears to be a curious deviation laterally of the temporal line, which swings back to the midline well behind bregma. On the R it appears that the temporal line diverged slowly from the midline after its anterior point of convergence.

TlUlKANA,

WKHT

(LriMKKWf,

I he squamosal (lows smoothly into the sphenoid, •>n
LoKALALP,!,

M AC II17 K LTI )

453

recurves in front toward the short and narrow cribriform. The optic groove is very pronounced, and the optic canals arc bounded laterally by small, minimally peaked anterior clinoid processes. Above the very steep clivus, the dorsum sellac rises very high, above the level of the jugum. The a/p short, but wide hypophyseal fossa is thus very deep as well. The clinoid processes arc damaged. The lesser wings of the sphenoid arc very short from side to side, but their superior surfaces arc more or less horizontal, and their distinct posterior margins extend posteriorly into the space above the middle cranial fossa. The small orbital fissures arc confined to the space below the lesser wings. The foramina rotunda arc fair sized and, because of the flatness of the floor of the middle cranial fossa, lie more or less directly behind, rather than below, the orbital fissures. Lateral to the clivus arc wellexcavated, almost vertical sulci (corresponding to the sphenoidal portion of the foramen lacerum in Homo sapiens). Lateral to these sulci arc large foramina ovalcs, the anterior parts of which are contained within the sphenoid and, as seen on the L, bounded posteriorly by the petrosal. (Since the foramen spinosum always lies behind and lateral to the foramen ovale, if the distal part of the foramen ovale lies outside the sphenoid, then so also must the foramen spinosum.) The superior surface of the petrosal is essentially flat and not very broad across. There is no sign of a superior petrous sinus. The region of the subarcuatc fossa is flat, but well below it lies a distinct horizontal sulcus that corresponds to the region just below the inferior semicircular canal. The alveoli for the l i s would have housed roots much larger than those of the smaller preserved laterals. The 12 crowns arc spatulatc and well shoveled on their lingual surfaces, and arc overlapped by the medial and lingual surfaces of the C, which lie at the "corners" of the tooth rows and the front of the jaw. The Cs arc small, worn flat at their tips, and would have been slender and triangular in profile. The somewhat worn Pis and P2s arc huge and broad, the P2 a bit bulkier than the P i but morphologically similar. The huge and slightly internally placed protocols are very bulbous on their lingual surfaces and contrast with the straighter-sided paraconcs. These two cusps are separated in the midline by a deep horizontal fissure bounded at either end by stout pjotoenstac hat terminate as thick styles on either side of the p cone, just internal to its lingual surface. These ensue bear para- and metaconulcs.

454

SITE

All Ms appear to be subequal in size; M 2 is possibly slightly longer than M l , but is less broad distally. The Ms are b/1 wider mesially than distally (this becoming more marked in the series M 1 - M 3 as the metacone decreases in size both m/d and b/1), and generally appear long m/d. All Ms bear a thick but short preprotocrista that emerges from the large and yen- internally expansive protocone and that arcs strongly mesially before coursing around the mesial side of the somewhat b/1-tnincated paracolic; a paraconule is present on this crest on M 2 - M 3 and was probably also on M l . Also on all Ms, there is a thick metaconule (or a yen' short postprocrista) between the bases of the protocone and the somewhat b/1truncated metacone, and a short postcingulum courses from midway up the side of the large, m/d compressed and b/1 wide hypocone along the side or the metacone. The M i s are worn quite flat, but only in the paracone region is the enamel breached at all. T h e paracone and metacone arc subequal in size; the protocone is large, almost eliminating the trigon basin, but is not very long m/d, especially compared to the M 2 , where it is much longer m/d. Next to it the hypocone is large on M l , but correspondingly smaller on M 2 . O n both M l and M 2 the postcingulum between the hypocone and metacone bears a relatively small conule. The M2s have a pronounced lingual slope that contrasts with a straighter lingual surface on M l . The enamel of the erupting M3s is deeply creased, contrasting with the flatter surfaces of the more worn molars in front, which were, however, probably originally also quite creased. T h e protocone is relatively large on M 3 for the size of the tooth, and the hypocone is relatively smaller. The paracone and metacone are subequal in size. T h e relatively thin M 3 postcingulum is subdivided into two conulelike structures. A metaconule lies at the bases of the protocone and metacone, and a thick preprotocrista courses anteriorly around the face of the metacone, being subdivided by well-marked creases. T h e lingual slope on the M3s is at least as marked as that on the M2s, if not more so.

O m o L74-A21 Lower Dental Morph (includes O m o L51-79 and L51-80 and K N M - E R 1 5 0 6 as well as KNM-WT8556A) KNMAVT 8556A. Mandibular fragment from L C alveolus to right M l . Alveoli for all Is and both Cs; P I - M l crowns, M l slightly damaged.

\

ENTRIES

Tooth rows would have converged markedly ward the midline, with all Is and Cs squeezed im narrow and slightly arced space at the front of the jmThe symphysis slopes back gently. Twin genial denrr sions lie within a common fossa that lies far up the internal surface oi the symphysis. Superior to this fossa is a ven* anteriorly inclined postineisal surface. The Is alveoli were compressed laterally, but deep; canine alveoli arc of modest size. The cheek teeth are only moderately large. In the P I , the metaconid is lareer at its base and more mesially placed than the centrally situated protoconid; the apices of these cusps arc quite far apart with a wide V-shaped valley between them. A moderately stout paracristid runs forward from the apex of the protoconid in a wide arc around the front of the tooth, before terminating at the apex of the metaconid to enclose a very large and upwardly facing trigonid basin. A postcingulid, which bears a scries of little peaks, emanates from near the base of the metaconid, distends the d/1 lingual aspect of the crown lingually (giving an oblique orientation to the crown), and then arcs around to the side of the the base of the protoconid; this cristid encloses a larger talonid basin that is contained primarily by the distal side of the metaconid and the internal side of the protoconid. This shelflike postcingulid is markedly lower than the paracristid. P2 is quite unlike P I ; while PI has an oblique axis, P2 is noticeably larger and quite rounded. T h e metaconid is larger than the protoconid, and lies distinctly mesial to it. In front of this pair of cusps lies a very thin and shallow fovea that is surrounded by a blunt paracristid that runs from the apex of the protoconid to the base of the metaconid. Posteriorly, the talonid basin of this tooth is large and expansive, and is ringed by a postcingulid that is subdivided into many cuspulids (cf. P2 in Omo L74-A21). The M l is missing some enamel from the front of the crown; it appears rather small relative to P 2 . 1 he protoconid apparently lay opposite the somewhat mesially placed and larger metaconid. A fairly stout paracristid courses a bit down from the apex of the metaconid and arcs gently mesially as it proceeds in a buccal direction, toward the protoconid; part of this region is missing. The prcscned stretch of paracristid encloses, between it and the metaconid, a relatively m/d long and fairly deep trigonid basin that would have spanned the front of the tooth in front of the two mesial cusps. The base of the wedge-shaped hypoconid extended lingually just beyond the midline, its apex

TUKKAN'A,

WEST

(LOMEKWI,

intruding between the bases of the very large mctaconid and much smaller and distallv placed cntoconid. A good-sized hypoconulid lies just bucciil to the midline, and just lingual to it is a small fovea. The apices of the lingual cusps are very marginally placed, and this side of the tooth is much straighter than the buccal side, where the cusps arc more internally placed. Notches separate the mctaconid from the cntoconid and the hypoconid from the protoconid and small hypoconuTid (cf. the more worn M l of KNM-ER 1506). Also, some fragmentary isolated teeth arc attributed to this individual. Most informative arc S556Ct left lower PI, a mirror image of the right PI in the jaw, and with two separate roots; and S556By a partial right lower M 3 . This latter is very wrinkled, with a narrow, moderately deep anterior fovea and the remains of a fairly large and buccally placed hypoconulid, distal to which would have been a small cuspulid. Cusp apices are relatively marginally placed; the outline of the tooth is ovoid. This specimen compares with KNM-ER 1820; it does not seem to go with the rest of the 8556 materials. K N M - W T 1 6 0 0 5 Lower Dental M o r p h KNM-WT16005. Upper part of a mandibular corpus from RM1 through LM2. It preserves only the roots of die Cs and Is; crowns of both P i s , P2s and M i s are present, as well as the L M 2 . All crowns are very worn and damaged. The front of the jaw is quite flat across, bulging at the long, stout canine roots. T h e inferior part of the symphysis is missing. T h e postincisal surface is long and gently sloping. T h e cheek-tooth rows are slightly arced, and diverge quite markedly behind the canines. The P i abutted the d/1 corner of the C. T h e roots of the Is are markedly compressed from side to side, and would have borne very narrow crowns. T h e C roots are best preserved on the L; they would also have been compressed, with a concave medial side; the crown would have been quite narrow. The cheek teeth are very large. T h e P i is somewhat smaller than the P2, which itself appears a bit small relative to the m/d long M l ; the M 2 was much larger b/1, and especially m/d, than the M l . P I is shorter m/d than wide b/1, primarily because it is strongly distended lingually in its d/1 region. T h e mctaconid was probably very mesially placed. T h e lingual side of the crown is thus oblique, and the tooth tapers a bit mesially. T h e P2 is somewhat larger than the P l , but is shorter b/1 than long m / d and subovoid.

LOKALALEI,

NACIIUKUI)

455

The subequal mctaconid and protoconid lie opposite to one another, and somewhat toward the front of the tooth. The postcingulid connecting these cusps enclosed a moderately sized basin that lay a little obliquely to the the long axis of the tooth. A tiny pit lies in the midline just anterior to the two cusps. Ms arc very damaged. A quite large hypoconulid on M l lay very slightly buccal to the midline of the tooth. On both M l and M2 the hypoconid extended lingually beyond the midline of the tooth. Possibly Nonhominid KNM-WT 16006A. L mandibular corpus fragment with roots of M l , a fragment of M2 and M 3 crown. Also a small piece of the anteroinferior gonial region. Root of ramus is visible, and would have covered part of the M 3 viewed from the side. Below M 3 the bone of the mandible thins dramatically at the inferior border, which is broadly but shallowly notched in front of a sharply descending gonial region that shows evidence for considerable thickening on its inferocxternal border. Judging from the roots, M l does not appear to have been appreciably smaller than M2, and both teeth seem to have been wide distally, in contrast to the preserved, distally tapering M 3 . T h e enamel of the preserved M 3 is thickly and deeply crenulated, and this tooth is distinguished in having a thick cingulid around the base of the large protoconid, which lies opposite a very m/d compressed but very m/d long metaconid. In front of the apices of these two cusps is a moderately wide and deep basin that is bounded mesially by a very thin paracristid. The metaconid and entoconid are very peripherally placed and their apices lie far apart, the space between them being occupied by low enamel ridges along the internal face of the metaconid. The very large hypoconulid is directly in line buccally with the protoconid and the hypoconid. T h e latter is the smallest of the three buccal cusps; it is somewhat m/d short and only gently tapering, and its blunt base just crosses the midline of the crown to contact the entoconid. Lingual to the hypoconulid is a relatively broad and narrow fovea. The buccal slope of the tooth decreases posteriorly, as the cusp apices become more marginally placed. Thus the talonid basin is more constricted anteriorly than posteriorly, and lies slightly oblique to the long axis of the tooth, its lingual margin being slightly displaced lingually anteriorlv.This is a very unusual morphology.

456

SITE

REFERENCES

ENTRIES

"robust" Australopithecus. In: F. E. Grinc (ed.), Evduf^ ary History of the 'Robust* Australopithecines. New Yo-tAldine dc Gruyter, pp. 2 5 9 - 2 6 S .

Arambourg, C. and Y. Coppcns. 1967. Sur la decouverte, dans lc Pleistocene inferieur dc la vallec dc l'Omo (Ethiopie), d'unc mandibule d'Australopithccicn. C. R. Acad. Set. Paris, D 265: 589-590.

Leakey, R. and A. C. Walker. 19S8. New Austrah^beaa boisei specimens from East and West Lake Turkana. Kcm-a. Am.]. Phys. Anthropol. 7 6 : 1 - 2 4 . *"

Dclson, E. 1987. Evolution and paleobiology of robust Australopithecus. Nature 327: 654.

Roche, H. ct al. 1999. Early hominid stone tool production and technical skill 2.34 Alyr ago in West Turkana, Kenva. Nature 3 9 9 : 5 7 - 6 0 .

Ferguson, \V. \V. 1989. A new species of the genus Australopithecus (Primates: Hominidae) from Plio/ Pleistocene deposits west of Lake Turkana in Kenya. Primates 30: 223-232. Harris, J. M. ct al. 1988. Pliocene and Pleistocene hominidbcaring sites from west of Lake Turkana, Kenya. Science 239:27-33. Holloway, R. L. 2000. Brain. In: E. Delson et al. (eds.), Encyclopedia of Human Evolution and Prehistory, 2nd ed. New York: Garland Press, pp. 141-149. Kibunjia, Al. 1994. Pliocene archaeological occurrences in the Lake Turkana basin./. Hum. Evol. 21:159-171. Kibunjia, A I. ct al. 1992. Pliocene and Pleistocene archeological sites west of Lake Turkana, Kenya. / . Hum. Evol. 23:431-438. Kimbel, W . H., T. D. White and D. C. Johanson. 198S. Implications of KNAI-WT 17000 for the evolution of

TURKANA, \ V E S T

Suwa, G. 19S8. Evolution of the "robust" australopithecines in the O m o succession: evidence from mandibular premolar morphology. In: F. E. Grine (ed.), Evolutionary History of the 'Robust* Australopithecines. New York: Aldine de Gruyter, pp. 1 9 9 - 2 2 2 . Walker, A. C . et al. 19S6. 2.5-Alyr Australopithecus boisei from west of Lake Turkana, Kenya. Nature 322: 517-522. Wood, B. A. 1988. Are "robust" australopithecines a monophyletic group? In: F. E. Grine (ed.), Evolutionary History of the 'Robust* Australopithecines. New York: Aldine de Gruyter, pp. 2 6 9 - 2 S 4 .

Repository National Aluseums of Kenya, P O Box 4065S, Nairobi, Kenva.

Figure 1. K N A l - W T S556A, partial mandible (scales = 1 c m ) .

TURKANA, W E S T ( L O M E K W I , LOKALALEI,

TURKANA, W E S T

TURKANA, W E S T

NACHUKUI)

457

Figure 2. KNM-WT 16005, partial mandible (scale = 1 cm).

Figure 3. KNM-WT 16006A, partial L mandibular corpus (scale - 1 cm).

jrfum NationaltfHistoireNaiureHe wpartement de Prebstoire 1,rueF«n4Panh*rd . _ m * m O

458

SITE

TURKANA, W E S T

ENTRIES

Figure 4. KNM-WT17000, partial cranium (scales = 1 cm; close-ups not to scale).

TURKANA, W E S T ( L O M E K W L

LOKALALEI,

T U R K A N A , W E S T F i g u r e 4.

NAGHUKUI)

{Continued).

459

SITE ENTRIES

460

TURKANA, W E S T

I

Figure 5. KNM-WT 17400, partial cranium (scales = 1 cm).

TURKANA,

WEST

(LOMEKWI,

TURKANA, W E S T

LOKALALEI,

Figure 5.

NAGIIUKUI)

(Continued).

461

PART

T H R E E

H O M I N I D CRANIODENTAL MORPHOLOGIES: A N OVERVIEW

HOMINID

GKANIODENTAL

Mt IUMIOLCUJIES: A N O V E R V I E W

Who needs to do this? The Gibraltar skull was described by Keith years ago. —Anonymous NSF grant proposal reviewer, 1996

INTRODUCTION Todays understanding of hominid systcmatics bears the firm imprint of a long history in which various distinct phases can be recognized, but which in recent years has been shaped by expectations emerging from the Evolutionary Synthesis as it was absorbed, in its "hardened" form, into our science around the middle of the twentieth century. In an influential contribution, the ornithologist Ernst Mayr (1950) set the tone for the next half-century in paleoanthropology by including all hominid fossils then known in only one genus and three species (Homo transvaalcnsis, Homo erectus, and Homo sapiens). T h e justification for this systematic compression was that human ecological diversity is and was so great that there arc and were, in effect, no vacant econiches that hominids could invade as a prelude to speciation. One consequence of this presumed ecological constraint on hominid diversity was to make morphology effectively a secondary consideration in the reconstruction of hominid

phylogeny. By the middle 1960s, however, the enlarging hominid record could no longer sustain this minimalist interpretation of diversity among the hominids known. As a result, Mayr (1963) found it necessary to reverse his earlier position and recognize the genera Australopithecus (and possibly Paranthropus as well) within Hominidac. Since then the extraordinary growth in the number of hominid fossils recovered, as well as of the sites from which they arc derived, has increased the number of hominid taxa generally accepted. However, this increase was still constrained by an underlying notion, in line with the dictates of the Synthesis, that human evolution had been largely a linear, and that the human fossil record was more usefully divided into "stages" or "grades," than into discrete species. This belief appears to be the major reason why such obfuscating categories as "prencanderthals" and "archaic Homo sapiens" were brought into general use. But while Mayrs acknowledgement came at a time when it was becoming fairly widely recognized

465

that at least a minimal number of ultimately extinct side branches might have existed in the course of hominid history, paleoanthropology continued to be driven primarily by the desire to document the gradual emergence oHIomo sapiens as the culmination of a central long-term trend. Under this construct, it became more important to know the age of fossils (so they could be fitted into the gradually modifying chain of ancestry of Homo sapiens) than it was to consider their morphology in any systematic context. Attention to morphology was directed to the description of what was seen as within-species variation at any one time, rather than to the analysis of potential systematic diversity. In recent years, the hominid fossil record has again expanded significantly, as has the range of morphologies evident within it. But while as a result it has become more acceptable to name new taxa on the basis of freshly discovered fossils (hence the outcry following the recent description by Meave Leakey ct al. [2001] of the new genus and species Kenyanthropus platyops was considerably more muted than the one that greeted Louis Leakey, Tobias and Napier's new species Homo habilis in 1964), it remains generally true that such new discoveries have not provoked paleoanthropologists to reevaluate previously known fossils in similar terms. Despite the many headlines proclaiming that one or another new fossil discovery should force rethinking of our entire conception of human evolution, in practice it is more remarkable how little rethinking has been done. Similarly, the ages of fossils often continue to take an unconscious primacy over their morphologies when their place in human evolution is being evaluated. In 1979 Nilcs Eldredgc pointed out the fundamental and historically important distinction between the linear "transformationist" mindset in the tradition of Mayr, and the "taxic" mindset, which emphasizes the identification and characterization of systematic diversity in the fossil record (ironically, in another tradition of Mayr's, but one that he never applied to hominids). In spite of the recent tendency to look more favorably than before on the creation of new hominid taxa, paleoanthropology today is still dominated by the transformationist view. Thus, for example, a recent anonymous referee of a manuscript (not ours) that raised the issue of whether Neanderthals and modern humans might represent separate species, dismissed this concern as "a return to nineteenth-century essentialism."

466

HOMINID GRANIODENTAL

Moiu'iioLonius: AN OVERVIEW

Undeterred by this, in these concluding remarks to this fourth volume of an essentially descriptive scries, we are motivated not only by the need to make at least a preliminary attempt to characterize and discuss the morphs we have discerned, but also by our perception that the evolutionary pattern evident within Hominidae is not linear, dominated by within-taxon variation. Rather, it appears to be one not only of morphological but of taxic diversity, reflecting evolutionary experimentation rather than fine-tuning. The presence on the planet today of a single hominid species is an atypical situation, possibly even an unprecedented one (Tattersall, 2000), and one that likely tells us more about the unusual nature of Homo sapiens than about what it means to be a hominid in general. Adoption of this perspective has the advantage of bringing hominid phylogeny into line with the evolutionary histories of virtually all other successful mammalian families, rather than obliging us to view our family as an exception for which we need to invoke a separate set of evolutionary rules.

SYSTEMATIC APPROACH TO THE HOMINID FOSSIL RECORD Our general approach in this discussion of the h o minid fossil record is to characterize, in a preliminary way, certain basic morphological groupings ("morphs") that may be recognized within the assemblages of fossils that make up that record. The recognition of species among extinct forms can never be more than a provisional process, but we do believe that at some level a systematic signal is reflected in morphology, and that this signal is a more instructive one than is furnished by either age or locality, the other attributes of fossils (see discussion by Eldredge and Tattersall, 1975). We also believe that the common possession of apomorphies among morphs is the surest guide to common ancestry, whether the morphs under consideration represent differentiated taxa or stable alternative morphologies within the same taxon. We realize that homoplasy is a problem to be contended with, but it is clear that homoplasies cannot be identified a priori> but instead require the acceptance of a particular theory of relationship before they can be recognized. Given that one systcmatists synapomorphies may well be another's homoplasies, we prefer in this

brief survey to raise questions and consider the alternatives, rather than attempt to provide definitive answers. Thus, while wc have characterized various morphological groupings based on our a preliminary survey, we arc reluctant to paint a hard-and-fast picture of hominid evolution based on a defined number of hominid species. Wc explore some of our reasons below. Species are almost as difficult to define in theory as they are to recognize in practice, but as namebearing groupings of organisms they have to loom large in any systematic account of a higher taxon. Wc cannot always be sure that the morphs we recognize in the fossil record correspond to species as wc perceive them (often not without difficulty) in the living fauna; but in cases where a significant number of apomorphies can be identified in a fossil grouping, wc can be fairly confident that a historically individuated entity is present (Tattersall, 1986). There is justification for regarding—and naming—at least a minimum of such entities as species. The more the apomorphies possessed by any such grouping, the more confident of this we can be; conversely, where distinguishing features are fewer or less distinctive, the probability that speciation has accompanied the morphological differentiation we detect diminishes, and there will always be gray areas of uncertainty. One of the major problems faced by those studying Hominidae is, of course, that this is a very close-knit group, in which many ot the morphological distinctions that are of potential systematic importance are likely to be subde. Many species have by now been named in the hominid fossil record, and because of the established rules of nomenclature and classification it is with these that one is obliged to begin all systematic reevaluations of that record. For obvious reasons, the place to start any species-level revision is with the holotype, the defining individual of each named species. It may be true that individuals resemble each other because they belong to the same species, rather than that they belong to the same species because they resemble each other, but under the existing rules of nomenclature (ICZN, 1999) wc are obliged to use the type specimen as the exemplar of the species, to which all other putative members of that species must be compared. This can sometimes be trick}'. The holotype may be fragmentary, or it may be difficult or even impossible^ to interpret in terms of apomorphies, as in the case ot worn dentitions. However, there is no alternative to morphological comparison of this kind in determining

H O M I N I P CRAXIODEXTAL M O R P H O L O G I E S : AN OVERVIEW

^~;*c critus. Wc are aware that there may often be ubstantial morphological variation among members f the same species, but we cannot know exactly how much variation is or was present in any individual case. We believe that it is preferable to err on the side of inclusivitv rather than exclusivity in systematic analyses; hut based on our observations of variation among congeneric species of living primates, we are confident that where distinctive and consistent morphs are present thev are highly likely to indicate bounded historical entities. In many cases fossil holotypes only represent small portions of the entire skeleton. In such cases it will be necessary to match holotypes with other comparable specimens that are positively associated with more complete representations of the skeleton. To take one example, a number of crania have been attributed to Homo beidelbergensis> but the holotype, the Mauer jaw, is actually an isolated mandible. To make the connection between the holotype and the crania it is necessary to match the Mauer jaw with another mandible that is positively associated with cranial remains. Fortunately, this can be done in the case of Homo beidelbergensis via comparison of Mauer to the Arago mandibles, which are in turn associated with cranial fossils. But it cannot be done in all cases. Occasionally a type specimen will not be diagnostic, either because it is too incomplete or because, as in the case of an excessively worn dentition, it lacks definitive morphologies. If the type specimen is an isolated fossil, unlike anything else known, such cases can quietly be forgotten pending fuller knowledge. And if an inadequate holotype is reasonably assigned to a larger collection that contains more diagnostic specimens, and these specimens themselves appear to represent a single morph, then it would seem appropriate to conclude that all belong to the same taxon. But should reappraisal of the entire hypodigm reveal that it is is not homogeneous, further practical difficulties will inevitably present themselves. However, under present rules there is no way to avoid proceeding along the lines we have indicated—and no preferable alternatives are on the horizon, PhyloCode and such to the contrary'. In the discussion that follows we have refrained from naming new taxa on the basis of the morphs we have identified, but we have attempted to place as many morphs as possible within previously named species. In a few places, where we were unable to amplify or significantly amend our text from the brief

467

notes we presented on the genus Homo in Volume 2, we have reproduced those notes with minimal or no emendation.

THE FAMILY HOMINIDAE AND THE EARLIEST HOMINIDS Current discussion about the family Hominidae and what it consists of has largely focused on the question of whether to include various other extant hominoids in the family (or even the genus) that includes Homo sapiens (Wildman et al., 2003, is a good case in point). Less attention has been directed to the question of tvby various extinct assumed relatives of Homo sapiens warrant inclusion in this family. The notion of H o minidae we adopt here is limited to Homo sapiens and its extinct nonape relatives, who together should form a monophyletic group. W h a t the closest relative is or was of the single common ancestor of this group is not relevant to this concept of Hominidae. Indeed, discoveries over the past few years have revealed a substantial species- and even genus-level diversity that fully justifies family-level recognition of this clade, regardless of where it falls in the wider systematic hierarchy. Truly cladistic classification is not workable in practice, and nothing dictates that our rankings should be from the top down rather than from the bottom up. Those who prefer to read "Homininae" or "Hominini" for Hominidae in the discussion below are welcome to do so. During the course of this study we have been confronted by an unexpectedly wide diversity of morphologies—especially dental morphologies—that makes it necessary, in our view, to inquire whether some accepted components of the hominid fossil record might not better be viewed as hominoid in a wider sense. For a long time, paleoanthropologists have been puzzled about the absence of "fossil apes," for following the end of the Miocene, when they are acknowledged to have flourished, "apes" seemingly disappear from the published record, just as hominids enter it. Perhaps, then, it is time for us to reevaluate the presumed hominid fossil record with the notion or diversity in mind. A case in point is O H 7, the holotype of Homo babilis. As discussed below, this mandibular specimen possesses few if any features apart from thick molar enamel that would s p e c i a l l y unite it to a

468

IIOMINID G l U N I O D E N T A L

M O K |»|| O LOG I KS : A N O V E R V I E W

monophylctic group that also includes Australopithecus and Homo. In contrast, in the morphology of its premolars, especially the P2, it is more comparable to Middle and Late Miocene hominoids such as Proconsul major and Ouranopithecus macedoniensis (Plate 1). Clearly, considerations of this sort suggest that the current concept of Hominidac will have to be rethought. Another illustration of this imperative is provided by the fact that sites in Africa as widely dispersed as Olduvai, Omo, Kanapoi and Stcrkfontein have yielded fossils that have been classified as Australopithecus, yet present a dental morphology that is more comparable to what is seen in the clade that also embraces the living Pongo. The molars in these morphs, for example, display compressed cusps that are incorporated into continuous cresting systems that surround broad, shallow basins with heavily crenulated surfaces—conformations that are not typical of mainstream Australopithecus. Over half a century ago, Wilfrid le Gros Clark (e.g., Clark, 1940) set the basic formula for our current understanding of the family Hominidae, using essentially the approach adopted by Huxley (1863) almost a century before him. Huxley argued that humans should be classified in the same larger group as the living apes, using the gorilla as his pivotal comparative element, and "tailed apes" as his outgroup. In his turn, Clark compared the crania, dentitions and postcrania of the then-known australopiths to those of living apes and humans, and concluded that, especially in the dentition, the australopiths were "more human than simian" (1940: 317). In other words, Clark looked among putative hominid fossils for "human" vs. "simian" features, and accepted as hominids forms, such as Australopithecus and Paranthropus, that showed a predominance of human resemblances. The underlying (and in retrospect erroneous) assumption appears to have been that "human" features must be derived, whereas "simian" ones are primitive almost by definition. Clark's basic approach has since been embraced almost universally in paleoanthropology, as witnessed by virtually every diagnosis of a new putative hominid published in recent years (e.g., White, Suwa and Asfaw, 1994, 1995; Brunct et al., 2002). In other words, paleoanthropologists have not been consistently concerned with diagnosing hominid taxa, including Hominidae itself, explicitly in terms of derived characters. Hence we have as yet no satisfactory apomorphybased morphological definition of Hominidae as a monophylctic group.

The earliest putative hominid yet to appear in the literature is represented by the holotypc and associated specimens of Sahelanthropus tchadensis (Brunct et al., 2002), which we have not yet been able to sec. The holotypc is a broken and somewhat distorted cranium from Toros-Mcnalla in Chad, central-west Africa. It is said to date between 7 and 6 Ma (probably closer to 6 M a than 7). All preserved teeth in the cranium are either broken and/or worn, and the same is true of the teeth in the referred lower jaw. Claimed derived hominid features of these fossils include small, apically worn canine teeth, indicating "a probable non-honing C-P3 complex" and "intermediate [between Pan and Australopithecus} post-canine enamel thickness" (p. 151). Additionally, "Several aspects of the basicranium (length, horizontal orientation, anterior position of the foramen magnum) and face (markedly reduced subnasal prognathism with no canine diastema, large, continuous supraorbital torus) arc similar to later hominids including Kenyanthropus and Homo" (p. 151). O n the other hand, the braincase is very small, the basicranium is elsewhere said to be longer than in Pan and Gorilla, and the nuchal plane is flat. T h e authors conclude that this combination of characteristics make their Sahelanthropus "the most primitive member of the hominid clade, close to the divergence of hominids and chimpanzees" (p. 151). However, based on the reported dimensions and comparisons, the brow ridge, for example, is taller and the interorbital region wider than in Australopithecus and the other hominoids in the comparative sample, and it appears that this brow structure, far from being primitive, was highly derived compared to both apes and australopiths (cf. Schwartz, 1998). W h a t is more, the flatness of the face and the lack of a canine diastema are both apparently more derived than in at least some of the presumed descendants of this form (most notably, Australopithecus afarensis). This specimen and its allocation illustrate how the lack of any satisfactory morphological notion of Hominidae permits a motley assortment of fossils to be accommodated within the family. Some features of Sahelanthropus are highly derived for any anthropoid. Such characters include the very broad interorbital distance, the tall and barlike supraorbital torus, the lack of a canine fossa and the very short, orthognathic face. Some features are primitive for Anthropoidea; these include the long basicranium, the long, flat nuchal plane and small brain size. Another category of traits arises from the assumption that Pan is the

IIOMINID G l l A N I O D E N T A L M

closest living relative of hominids and that its features represent the ancestral condition. In this perspective almost any feature that can be seen as "intermediate" between the conditions present in the chimpanzee and any Australopithecus or Homo can be interpreted to indicate hominid affinity. In this case, dental enamel thickness and the position of basion are duly invoked. Two features of Sahelanthropus are claimed to be specifically hominid. These are canine-tip wear— which is also claimed as a genus-specific trait and only emerges from a comparison with Ouranopithecus— and the somewhat forward position of the foramen magnum. From the very clearly reproduced illustration provided (Brunet et al., 2002, Fig. 2d,e), the specimen identified as the right lower permanent canine of S. tchadensis is of very unusual morphology not only for a hominoid, but for an anthropoid. An enlarged cingulid such as the one shown would be more characteristic of a deciduous tooth, and in general among mammals the morphology of the upper canines is more complex than that of the lowers. This would imply that this unusual tooth is more likely to be an upper than a lower, whatever taxon it may represent. It may, indeed, be an anterior premolar of a carnivore. The forward position of the foramen magnum is inferred from the fact that basion in Sahelanthropus lies on the bicarotid chord, behind which this point is found in large apes, and anterior to which it is found in "some of the later hominids." Significantly, a forward shift of the foramen magnum is taken to imply upright bipedality on the part of Sahelanthropus. This is important because in recent years, in the absence of any workable morphological definition of the family, the inferred behavioral attribute of bipedality has become the touchstone for hominid status. However, the position of the carotid foramen is dependent on where it lies in the petrosal, and on the degree of flexure of the petrosal relative to the ectotympanic tube. In our own survey of various juvenile and adult catarrhine skulls, including those of great apes, we noticed subtly different configurations of these petrosal features. In juvenile Homo, Gorilla, Pan, Pongo, Colobus and Cercopithecus, basion and the bicarotid and biporionic chords lie more or less along the same axis. In the juveniles of all of these but Cercopithecus, basion also lies roughly on this axis. In adult Colobus and Cercopithecus the bicarotid chord lies slightly anterior to the biporionic chord, and basion lies noticeably posterior to the carotid foramen, but less far behind the biporionic

OKIMIOLOGIES: A N OVERVIEW

469

chord. In adult large-bodied hominoids the biporionic and bicarotid chords essentially continue to coincide, while basion lies variably posterior to both, most noticeably in Gorilla. In juvenile Mandrillus basion lies on the biporionic chord, but behind the bicarotid chord. The disparity between these two chords increases with age in this genus, but the relation between basion and the biporionic chord remains more or less constant. Given that in juvenile and adult Cebus the bicarotid and biporionic axes coincide, it seems reasonable to conclude that this configuration is primitive for catarrhines. Since the position of the carotid foramen can thus shift both with reference to the biporionic axis and in its relationship with basion among catarrhines, it is hard to conclude that it makes a particularly good reference point for fixing the inferred position of the foramen magnum on the skull base. Sahelanthropus was claimed by its authors to be hominid largely on the basis of features in which it was considered to be derived, or at least non-ape-like. In contrast, the describers of another claimed early hominid, Ardipithecus ramidus from 4.4 Ma deposits at the Ethiopian site of Aramis, sought to demonstrate that this form was ancestral to species of Australopithecus younger than it. In arguing for this interpretation they thus emphasized their new taxon's more apelike, hence primitive, features (White, Suwa and Asfaw, 1994, 1995). The authors' intent is implicit in the fact that the amended diagnosis of the genus Ardipithecus (White, Suwa and Asfaw, 1995) is essentially identical to that of the species Australopithecus ramidus given in the initial publication (White, Suwa and Asfaw, 1994). The only difference between the specific (1994) and generic (1995) diagnoses is that the latter eliminates the original flat statement that "A. ramidus is a species of Australopithecus" (1994: 306), and adds that the genus Ardipithecus has less postcanine megadontia than Australopithecus (which can also be said for the genus Homo). We have not been allowed to see the specimens concerned, but—in keeping with their assertion (1994: 312) that "the two derived craniodental characters shared among all hominids are anterior placement of the occipital condyles/foramen magnum andean incisiform canine with reduced sexual dimorphism White, Suwa and Asfaw argue that ^dipjthecus ramidus is hominid on the basis of a modified C-P3 complex, an anterior foramen magnum, and proximal ulnar morphology (shared with later Australopithecus

470

II OM INI I) G U A N I O D B N T A L M O K l» II O LOG I 10 S : A N O V E R V I E W

species)" (1994: 312). In other features they describe Ard'tpitbecus as "ape-like," which helps them distinguish it from Au. afarensis, and is consistent with their generalized claim that "A. ram id us is the most apelike hominid ancestor known." With the apomorphics of Hominidac thus effectively reduced to two or three, accurate inference of the position of the foramen magnum on the cranial base becomes critically important. The published photograph of the basicranial fragments of Ard'tpitbecus (White, Suwa and Asfaw, 1994: 307, Fig. lb) shows that the preserved left carotid foramen lies on the axis of the cctotympanic tube, as in Sahclantbropus (and, indeed, in most catarrhincs). But as we have already suggested, this is not a reliable guide to the relative position of the foramen magnum. Indeed, this relationship is highly variable among hominids in general. A brief survey of hominid specimens in which basicrania arc reasonably preserved yields the following observations. Basion and the biporionic and bicarotid chords arc more or less in transverse alignment in Sts 19, M L D 3738, Eliye Springs, Sima 6, Fish Hock, Dolni Vestonicc 3 and 16, Ngandong 14 and possibly also O H 9 and K N M - W T 15000. The biporionic chord and basion coincide, with the bicarotid chord lying posterior in Sts 5, O H 5 , Kabwc and La ChapclIc-aux-Saints, and anterior in Sima 5. The bicarotid chord and basion are level and anterior to the biporionic chord in A L 444, Ngawi 1 and SK 47. In Ngandong VI the two chords arc coincident, and basion lies behind. In T M 1517a the carotid foramen lies anterior to the ectotympanic tube, and basion was at least level with, if not anterior to, the foramen. In the Dmanisi cranium D2700, basion lies distinctly anterior to the bicarotid chord, which lies in front of the biporionic chord. In Sima 4 the biporionic chord lies anterior to both basion and the bicarotic chord. And so on. None of these landmarks is thus an infallible proxy for the position of the foramen magnum. This is not necessarily to deny that Sabelatttbropus and Ard'tpitbecus were upright bipeds of some kind. But if they were, it remains to be demonstrated on other evidence. T h e other craniodental feature of Ard'tpitbecus that is considered diagnostic for Hominidac by White, Suwa and Asfaw is the "modified C-P3 complex" with "an incisiform canine with reduced sexual dimorphism." Based on a rather unclear illustration (1994: 307, lig. 1), the upper canine of Ard'tpitbecus is an m/d long but low-crowned tooth that is distinctly pointed,

with an equilatcrally triangular profile and anterior and posterior styles. White, Suwa and Asfaw describe this tooth as "slightly less incisiform than homologucs of//, afarensis but more incisiform than any ape counterpart, with occlusally placed terminations of the mesial and distill apical crests" (1994: 308). In fact this tooth apparently is a fairly close morphological match not only for the upper canine of Kanapoi A anamensis, but also for the upper canine of female orangutans. Which implies in turn that a canine morphology of this kind is not an infallible indicator of hominid status. Further, the claim that this tooth in Ard'tpitbecus is more "incisiform" than it is in A. afarensis would seem to be contradicted by the morphology of the canine in the Laetoli specimen L H 3 , in which the divergence of the mesial and distal slopes appears to be more or less identical. The argument that the upper canine from Aramis appears blunter (more incisiform) than ape homologues seems to be based in part on the presence of mesial and distal styles (the distal style is not illustrated in the drawing presented [fig. 3g], although it is described in the text and is visible on the photograph [fig. la]). However, it is noteworthy that these styles are typically absent in A. afarensis, the presumed descendant of Ard'tpitbecus. Although White, Suwa and Asfaw refer to a "modified C-P3 complex," the only component of this complex that is modified under their interpretation is the upper canine, since the lower anterior premolar is described as being "indistinguishable from ape homologues" (1994: 308) in major features. Recently, the geological range of An ratmdus was considerably extended by Haile-Selassie (2001), who attributed to this species various fossils from Ethiopian Middle Awash localities dating in the range of 5.8-5.2 Ma. These he assigned to a new subspecies, Ar. r. kadabba, based on a holotype mandible and associated teeth that are too worn to be helpfully diagnostic. Apart from the fact that it is rarely considered useful in paleoanthropology to recognize subspecies, doubts have been expressed (D. Johanson, pers. comm.) as to the proper association ot the motley assortment of teeth, mandibular fragments and postcranial elements, from sites widely dispersed in time and space, that is assigned to the new taxon. Further, Haile-Selassie claims that the new Ard'tpitbecus material shares "derived dental characters exclusively with all younger hominids" (2001: 178), a claim not made by White, Suwa and Asfaw for the later Ard'tpitbecus^ material, and not substantiated by Haile-Selassie. 1 hese,

H O M I N I D C R A N I O DENTAL M O R P H O L O G I E S : A N

too, arc fossils that wc have been unable to examine; but on present evidence it seems clear that they have not yet contributed significantly to a workable morphological definition of Hominidae. J he other very early contender for hominid status is the species Orrorin tugenensis, recently described by Scnut and Pickford (2001) from sediments probably dating to just under 6 Ma at Lukcino in northern Kenya. The evidence on which this new taxon is claimed to be hominid is in large part postcranial, based on inferred upright bipcdalism. It is thus beyond the scope of our discussion here, although wc can see little reason to contest the described interpretation of the postcranial remains as those of an upright biped of some kind. Certainly, the apparent angulation of the femoral shaft suggests bipcdality. T h e dental remains included by Scnut and Pickford (2001) in the Orrorin hypodigm include two mandibular fragments with L M 2 - M 3 and R M 3 , an upper RC crown and an upper I I . The incisor is huge, but is damaged and not highly informative. T h e canine is very low-crowned, with mesial and distal edges of approximately equal length. In these features it resembles the upper canine described for Ardipithecus, but it has a much blunter tip. This tooth also lacks the stylar adornment of Ardipithecus, but the termini of the mesial and distal edges curve in to the neck, as they do in the Ethiopian specimen. Unfortunately, none of the upper canines from the Middle Awash, Lukeino or Toros-Menalla appears to help answer the question of whether significant canine size dimorphism was typical of any of these early forms. T h e Orrorin mandibular fragments bear smallish molars, and the broken L M 3 especially shows that, as noted by Senut and Pickford (2001), the molar enamel was thick, significantly more so than that described for Ardipithecus, and probably also for Sahelanthropus. If thick molar enamel is indeed primitive for Hominidae, then all molars attributed to Orrorin, unlike Ardipithecus or even Sabelantbropusy are straightforwardly hominid in this feature. T h e best-preserved molar in the original hypodigm of Orrorin is the L M 3 of BAR 1000'00a. This specimen resembles some isolated M 3 s from the Shungura Formation of the O m o basin (e.g., L628-3 and L795-1) in features that include a tongue-like extension of the hypoconid well across the midline of the crown to contact the base of the metaconid, and a very unusual kind of enamel wrinkling consisting of tiny fissures running down the internal surfaces of the cusps (Plate 2).

O V E R V I Es\v

471

What the contemplation of these three very different taxa of putative early hominids most clearly emphasizes is the need for paleoanthropologists to focus more intensely on a morphological definition of the family Hominidae. For just as Linnaeus (1735 et seq.) was content to skip over the diagnosis of the genus Homo with the comment "nosce te ipsum? so too have paleoanthropologists been comfortable with describing fossil specimens as hominid in the absence of an effective morphological notion of the family. To return briefly to this theme, Clark encapsulated this feeling well in his influential contribution of 1940 when he argued that the australopiths then known were more Homo-X\kz than apelike, and thus that their "zoological relationship to the Hominidae can hardly be doubted" (1940: 330). Yet in the absence of a workable morphological definition of what makes a fossil a hominid, how is it possible to look at a tooth or a fragment of jaw and say, "this is a hominid"? And even if the defining characters of Hominidae prove to lie elsewhere in the skull than in the dentition, and/or in the postcranial skeleton, it will be important to know that isolated dental elements cannot be diagnostic. In this preliminary study we have been able to identify a range of distinct (if sometimes clustered) morphs in the spectrum of fossil materials that have been considered hominid. Further, all of these morphs may not be strictly hominid, in the sense that they represent species that belong to a monophyletic group that also embraces Homo sapiens while excluding any living ape and its extinct relatives. Although we cannot hope to solve this conundrum here, we trust that our characterization of morphs will be helpful in ongoing efforts to understand the intriguing variety of fossils that have been attributed to early members of Hominidae.

OPERATIONAL PROBLEMS IN THE ALPHA TAXONOMY OF THE "EARLY HOMINIDS" In attempting to sort into morphs the numerous claimed hominid fossils now known from the Plio-Pleistocene of eastern and southern Africa, we have encountered several practical problems, some of which wc have already mentioned. Possibly the most important of these is the fact that much of the

**'*•

IIoMlNID

G RAX JO DENTAL M

hominid fossil record consists of teeth, either isolated or in jaws of varying completeness. For reasons of preservation, teeth are inevitably the largest single component of the record of our evolution; but fossil teeth are often damaged, or are worn down beyond diagnostic and comparative utility. Because of this we need to recognize the ncccssirv of excluding part of our potential database from our deliberations. Further, individual regions of the skeleton, including the jaws and teeth, may not necessarily contain diagnostic hallmarks of the species to which they belong. Definitive statements arc thus difficult to make about a large proportion of the fossils that are claimed to tell us about our ancestry. This causes particular difficulties when paleoanthropologists have chosen (or have had to choose) name-bearing holotypcs that consist of jaws with significantly worn teeth. One good example is furnished by the type specimen of Australopithecus anamens'is, KNM-KP 29281, right and left mandibular halves that contain both broken and highly worn teeth (only the P i s , M2s and M3s provide any morphology at all). How do we compare a wide range of potential conspecifics to a holotype like this to determine whether or not all belong to the same species? We can only hope to find more complete and unworn specimens that will serve as a "bridge" to others. In addition, teeth of distinctively different morphology in their freshly erupted state may wear down to produce a closely similar overall effect. As long as some occlusal morphology remains, close scrutiny of the morphology of worn teeth often reveals many original structural details, but such scrutiny is rarely applied to potential hominid fossils. Instead, the overwhelming tradition in paleoanthropology has been to rely on the "overall resemblance" and/or metric approaches, in which two specimens that were originally morphologically distinct can easily turn out in their worn state to have a strong general resemblance or to possess virtually identical dimensions. A typical example is provided by figure 13 in White et al.'s (2000) analysis of the lower jaws from Maka.This illustration shows three mandibles, from Maka (MAK-VP-1/12), Hadar (AL 400-la) and Laetoli (LH4), all of which arc claimed to be similar and thus to represent the species A. afarensisy of which the Laetoli specimen is the holotype. However, as our descriptions and photographs in this volume demonstrate, these three specimens, while of generally similar size, mandibular outline and (worn) dental configuration, actually display traces of distinctive detailed dental morphologies.

RPHOLOGIES: AN

OVERVIEW

The fact that these morphologies can indeed be discerned suggests that it is at least worth considering that lumping them conceals a more complex biological reality. Another problem, at which we have already hinted, is associating the various morphologies seen among the fossils under study. Ever)' vertebrate individual possesses an upper and lower dentition and a cranium, plus a postcranial skeleton with a bewildering number of bones. But it is rare that a fossil assemblage will furnish any positive association between disarticulated elements. Where an assemblage onlv contains one morph per family, there will normally be no problem of association, but where a site furnishes evidence of more than one similarly sized morph per related group, problems multiply. Nowhere is this more true than at the South African australopith sites. At most of these sites we have been able to discern more than one distinctive morph based on upper or on lower dentitions, or on cranial structure. But in many cases the process of associating these anatomically restricted morphs is tenuous at best. This is why in the descriptive sections of this volume we have preferred to describe upper and lower dental and craniofacial morphs separately, except in unusual instances (such as that of K N M - W T 15000) where unquestionable associations exist. The result of this is that we have substantially more morphs than taxa, but for now no better solution is available. Finally, close attention to detailed morphology can give rise to its own problems in the study of any closely knit group, since it highlights features that are easily disguised in more coarsely grained analyses. For example, one of the dental characteristics that has been considered more or less diagnostically hominid is the possession of low-cusped, thick-enameled molars. Indeed, the vast majority' of the teeth comprising the early hominid fossil record are large and flatly worn molars. However, if ones focus is limited to specimens from the P l i o - Pleistocene of eastern and southern Africa in which the teeth are pristine or only minimally worn, one finds that such teeth are often highcrowned, not only possessing distinctly defined cusps, crests and other features, but also displaying a variety of markedly different occlusal configurations. Such configurations are usually dismissed as "variation. However, there is an alternative explanation. As we hope will be evident from descriptions in this volume, as well as the comparative illustrations in this section, there exists a much higher diversity in dental

MOM IN ID C U A N I O D E S T A L M o K I M I O L O O I E S ! A N O V E U V I E W

morphology than is usually acknowledged. Although some of this diversity is doubtless due to within-taxon individual variation, ironically, if any of it is of systematic significance, it becomes more difficult to arrive at a satisfactory dental definition of Hominidac.

THE "AUSTRALOPITHS Since its naming in 1925 the genus Australopithecus has come to embrace a large variety of fossil materials from southern and eastern Africa, plus Chad. So extensive a variety, indeed, that it is not unjustifiable to claim that Australopithecus (and the derived "Australopithecinac") has become essentially a "wastcbasket" taxon, one that is conveniently embraced in its widest application by F. Clark Howell's more informal term "australopiths." Currently, it is actively debated whether and how the genus Australopithecus ought to be broken up (most commonly, by recognizing the genus Paranthropus for the "robust" forms), but as the following descriptions of morphs make evident, there are problems with all of the proposals currently on offer. For example, the morph represented by the Taung-type species A. africanus subsumes the type specimens of other accepted australopith species (e.g., part of the holotype of Paranthropus robustus from Kromdraai), while the conventionally accepted allocation to species of specimens from the other australopith sites clearly requires revision, a task beyond the scope of our review here. Below we briefly survey the records from these various African sites, make some preliminary suggestions as to groupings of fossils that may be distinctive and note where difficulties arise.

SOUTHERN AFRICA The obvious place to start trying to understand the complex australopith radiation is with the type site of Taung, which fortunately presents us with an unquestionably associated upper and lower jaw, together with the facial skeleton (and natural endocast) of the same individual. Further, even though the skull in question is that of a young child, and certain features such as the mature supratoral configuration are thus not yet developed, there are still aspects of the lower orbital and infraorbital regions that provide useful comparative information. This combination of advantages

473

allows us to proceed with dental comparisons to adult specimens that arc associated with facial features and that thus lead us to the adult facial condition of the Taung species, by definition Australopithecus africanus. The Taung cranium contains the stubs of the upper deciduous incisors, plus the worn dc—dm2 and unworn M l . The upper Ldm2 of Taung is somewhat worn, but one can still see traces of a thick postprotocrista. There is also a notch between the subequal protocone and the less lingually placed and b/1 wide hypoconc, from which a short postcingulum emerges and arcs to the side of the mctacone.The protocone is not very internally placed. The unworn M i s are tallcrowned, with somewhat internally placed cusp apices. The enamel is thickly crenulated, and the postprotocrista is thick, while the mesially arcing preprotocrista is rather faint. A narrow wedge of enamel intervenes between the protocone and the hypocone, from which a short, thick postcingulum runs to the side of the metacone. The apex of the hypocone lies somewhat distal to the apex of the metacone, and the tooth is thus longer m/d along its lingual than its buccal side. The metacone lies close to the slightly larger paracone. The upper M i s of the Sterkfontein specimen StW 252 can be seen as similar to the M i s of Taung when the effects of wear are taken into account (Plate 3). Most notable among such effects is the broadening of the hypocone such that it appears to migrate forward and to have a broader contact with the metacone. The less worn upper M 2 of StW 183a is more recognizably similar in morphology to the M l of Taung, although there is still more contact between the hypocone and the metacone. The distal curve seen in the upper M i s of Taung, StW 183a and StW 252 is slightly more accentuated than in the preserved upper M 2 of S t W 183a. In the upper M 2 of StW 252 this distal curvature is more marked and, combined with a relatively smaller metacone, produces a tooth that appears to be arcuately truncated in its distobuccal region. This, however, is reasonably interpreted as within-morph variation, as are the observations that the postcingulum in the upper M2s of StW 252 and 183a is creased, making it appear as if a conule is incorporated into it, and that in the former specimen there is a trace of protocone cingulum on all molars. In these two individuals the upper M l is noticeably smaller both m/d and b/1 than the M 2 ; and, expanding the morph yet again, the upper P I and the alveolus for upper P2 in S t W 183a also illustrate that the

4/4

I I O M I N I I ) GKANMODENTAL MOIII'IIOLOCIIKM: A N

premolars are large relative to M l . In StW 252 the upper M 3 vet further accentuates the distal curvature already seen in the M2, and it is also evident that in this unworn tooth, which is quite long m/d and narrow b/1, the hypocone is more distal to the metaconc than it is in the more worn anterior molars. As in StW 183a, the upper premolars of this specimen appear large relative to the M l , and the preserved canine and incisors arc also relatively large. The canine is tall, pointed and subtriangular in buccal outline, with a thick basal lingual cingulum. Even though somewhat worn, the central incisor is quite tall-crowned, and is markedly larger than the 12. The upper dental morph just characterized can also be identified at South African sites other than Taung and Stcrkfontcin, including Makapansgat (e.g., M L D 6, 9, 30, 44 and 45) and Kromdraai (e.g., T M 1512, 1517a and 1561) (see Plate 3). Parenthetically, we should note that since T M 1517a is part of the holotypc ofParanthropus robustusy if this is to continue to be regarded as a valid name, the holotypc should be restricted to the mandible T M 1517b. Other Stcrkfontcin specimens that are also allocable to the Taung upper dental morph include Sts 1, 2, 17, 12, 32, 42 and 52a, and S T W 11, 151 [in part], 283 and 498a. There are also many other more worn specimens from all of these sites whose allocation to the Taung upper dental morph is possible, but hard to demonstrate with any certainty. At Swartkrans, the straightsided palate and the occlusal shape of the very worn preserved molar of SK 847 most closely resemble what is seen in S t W 252 and 498a. Additionally, the small size of the preserved 12 and the large II and canine alveoli of SK 847 also make a match for the Taung morph that these specimens represent. The emerging picture of morphs based on upper dental characters becomes complicated when one considers details of facial structure. Notable features of the face of the Taung child include a quite sharply angled infcrolatcral corner of the orbit; a depression below this region around the area of the zygomaticomaxillary suture that emphasizes this corner further and makes it appear everted or thickened; an infraorbital foramen that lies well below the inferior margin of the orbit and lateral to the superior terminus of a distinct facial "pillar" that emphasizes the presence of a flat "snout" that is well demarcated from the rest of the face; and lateral margins of the nasal aperture that arc blunt and rounded, and that curve in smoothly toward the midline. With the exception of the

OVKUVIEW

depressed zygomaticomaxillary region, these features arc also seen in the adult facial fragment StW i s l and in comparable features, M L D 6 and TM 15\-j\ likewise comfortably fit into this group, which shows a distinct morphoclinc in the delineation of the "snout," from the relatively poorly demarcated StW 183a to the aggressively outlined T M 1517a. Also seen in T M 1517a is a very marked depression below the orbit that creates a distinctly thickened and everted inferior orbital margin (Plate 4). Interestingly, few if any of the "classic" examples of A. afrkanus from Stcrkfontcin (e.g., Sts 5, 52a and 71, StW 505) conform to this overall facial configuration, even though the upper dentitions of Sts 17 and 52a can be fitted into the Taung dental morph. Given the difficulties we have experienced in determining the boundaries of the Taung upper dental morph as represented in the Stcrkfontcin sample it seems that, while the Stcrkfontcin hominids show a distinct variety in facial form, the dentitions of the various facially distinct morphs have remained primitively similar. Nonetheless, despite the ambiguity of much of the dental evidence, the existence of multiple facial morphs among these hominids docs appear to be real enough. Sts 52a might possibly be allied with the Taung/Kromdraai facial morph by virtue of a "cornering" of the infcrolatcral portion of the preserved orbit, and in possessing a facial pillar that runs from the canine to the level of the infraorbital foramen and delineates a blunt edge between the "snout" and the area lying behind it. Sts 5, on the other hand, exhibits a pillar that is largely restricted to the lateral margins of the nasal aperture, as also does Sts 17. Sts 5 also has a large infraorbital foramen that lies well below the infraorbital margin and that empties into a gutter below. Unlike the Taung/Kromdraai morph (but like Sts 17), its snout is squarcd-off and more projecting, especially in the alveolar region. Sts 71 and 505 plausibly form a facial morph distinct from Sts 5/17 (sec Plate 4). This morph is characterized by tall, ovoid orbits, very long nasal bones extending noticeably below the infraorbital margin, and the relationship of the face to the neurocranium, notably in the configuration of the massive anterior root of the zygomatic arch (which diminishes rapidly posteriorly), and the tall and laterally oriented masseteric origin. Posteriorly, the auditory meatus is triangular in outline in both specimens, with the apex inferiorly oriented ami the mastoid region wrapping around below it. As for basicranial structure, Sts 5 is

II O M I N I D C R A N I O DENTAL M o u r n o LOG I E S : A N O V E K V I El \V united with the Makapansgat specimen M L D 37/38

i • . . , - •-•iglv tapering basioccipital just in front of the condyles (Plate 5). A t Swartkrans a very distinctive upper molar morph is well represented bv SK 11, 13, 46 48 49 52, 65, 79 and 83, and SKW 11. The M l ' i s short m/d, with a short metaconc that has an m/d short and b/1 wide hypocone lying opposite it. The hypocone is separated from the trigon by a groove that runs directly buccally from the lingual margin for some distance, and then arcs strongly distally to terminate at the midline in a small postcingulum that is also delineated internally by a deep but short groove. As seen in the relatively worn upper M 2 and the unworn upper M 3 of SK 13, the metaconc starts off incorporated into a very thick postprotocrista that is continuous with the preprotocrista. Together these two crests, which are very internally placed, isolate the large paracone. Interestingly, this unusual conformation of the paracone and the surrounding structures is most closely echoed not in South Africa but in the molars of the Kenyan specimen K N M - W T 17400. In the latter specimen the upper canine is also small and the premolars are large relative to M l , just as in SK 48. In the SK 48 morph the upper M 2 is slightly larger than M l and possesses the same basic features, except that the hypocone may be less lingually projecting. M 3 is slightly larger again, has an even smaller metacone, a slightly more distal hypocone that is delineated by a similar groove and a protocone that expands lingually. As noted earlier, the premolars in this morph arc large relative to the M l , the P I being slightly smaller than the P2. In both premolars a thick crest runs around the paracone from its mesial to its distal side. T h e anterior teeth are relatively narrow m/d, but except for the very small, spatulate 12 are quite tall in the unworn state. T h e dental arcade is tightly curved across the front in most examples of this morph (not SK 48), with long, moderately diverging cheek-tooth rows. Facially, however, this group of Swartkrans specimens is more diverse. SK 48 and the crushed SK 79 are comparable in the infraorbital, supraorbital, mterorbital and L zygomatic regions, where they show very s/i thin supraorbital margins from which the frontal retreats almost horizontally. T h e supraorbital rims themselves arc gently over each orbit and descend to become confluent with a very broad and projecting glabellar region. T h e interorbital region is

475

extraordinarily wide, and just below the infcrolatcral corner of the orbit the zygomatic is quite swollen locally. In SK 48 this swelling occurs along the shallowly sloping zygomaticomaxillary suture. This conformation contrasts with what is seen in SK 46 and 52, where in comparable parts the supraorbital margin is noticeably thicker s/i. Compared to SK 48, these specimens have less vertical and deep infraorbital regions, and in profile the zygoma curves back instead of remaining vertical. In SK 48 there is a large, shallow depression below each orbit that is lacking in SK 46 and 52. The lower faces of SK 46 and 52 arc relatively much smaller than their very tall and broad counterpart in SK 48. In SK 46 and 52 the facial pillar emerges from above the region of the canine, and arcs up and inward, where it would have demarcated a roundedly triangular "snout." In SK 48 the lower face is essentially flat, lacking pillars. In SK 52 the infraorbital foramen lies very close to the inferior orbital margin, while in SK 48 the foramen lies much lower (as it also docs in KNM-WT 17400). Given their size differential, it is possible that SK 46 and 52 represent, respectively, the male and female of the same facial morph. T h e upper dentition of D N H 7 from Drimolcn bears a general similarity to the morph just described from Swartkrans, but a close comparison is with the almost identical Sts 53a palate from Stcrkfontein (Plate 6). Resemblances between D N H 7/Sts 53a and the Swartkrans group include a broad arc around the front of the palate, and the shortness of the almost parallel cheek-tooth rows. The general disposition of the upper molar hypoconcs and metaconcs is also broadly similar, but in both D N H 7 and Sts 53a all molars are relatively short m/d and wide b/1. As preserved in D N H 7, compared to the Swartkrans morph the premolars arc relatively larger, and the anterior teeth relatively smaller. On the M 3 of D N H 7 the Groove that delineates the hypocone runs diagonally from the lingual edge of the tooth to the distal edge of the small metacone, and in general this unusua tooth is similar to that of Sts 53a. The palate. StW 53b, initially supposed to represent Homo habths, also falls into this morph dentally, although the •wjciatcd frontal Stw 53a is a poor match for that of D M 1 7. T h e face of D N H 7 is distinctly different from that of SK 48, being relatively narrow and taller and eking all supraorbital toral development. The orbits of D N H 7 are tall and ovoid, whereas those of Sk 48 e^omewhat "aviator glasses-shaped, the infraorbital

476

IIoMIXII) C K A N I O D E N T A L .

M O 111*11 O LOG I ES : A K

foramen lies higher and more medially in D N H 7, and the nasal aperture of Drimolcn would have been quite narrow in contrast to the wider aperture of SK 48. In addition, the frontal of D N H 7 rises quite steeply from the supraorbital margins, in contrast to the flatter profile of SK 48, than which it also has a much narrower intcrorbital region. D N H 7 is also sharply distinguished in its facial construction from SK 52j having in profile a moderately dished face that is almost totally flat across, lacking any definition of a snout or any superior orientation of the zygoma. It D N H 7 originally resembled Sts 53 in its broken infranasal region, it bore a distinct facial pillar running up from the alveolar margin of the canine to just above the inferior nasal margin. This is another characteristic that would distinguish the Drimolen form from both SK 48 and SK 52, albeit in different ways, and unite it with StW 53b. There also appear to be other South African morphs that differ from that represented at Taung. One of these differs in having a thick lingual cingulum on the upper molars that either wraps around the protocone or goes fully around the lingual side of the tooth. In this morph the hypocone also becomes less distinct from M 1 - M 3 , as is apparent for example in Sts 37, even though M 1 - M 2 in this specimen are rather worn. Sts 12,22 and possibly 35, and M L D 44, also show these characters. Another distinctive molar morph is represented by SK 27 and 55a, which have very thick pre- and postprotocristae. The thick preprotocrista runs mesially around the paracone, from which it is distinguished by a groove. This crest truncates the cusp m/d and terminates in a distinct parastyle. There is essentially no development of a postprotocrista. The hypocone is swollen m/d and quite wide b/1. A thick postcingulum runs from the distal side of the metacone to the d/1 portion of the tooth, becoming fainter en route but enclosing a small but deep and distinct talon basin between it and the postprotocrista. Isolated teeth from Kromdraai that may also lie in this group include two RM's assigned to T M 1517, and possibly also the LM 3 KB 5222. Finally, it may be worth noting that the R maxilla Sts 24a, containing d m l - M l , is similar to SK 27/55a in the visible morphology of its worn dm2, and in the presence on its M l of a deep fissure internal to the postcingulum and an m/d compressed hypocone. The M l of Sts 24a also has a well-developed preprotocrista, but this crest docs not terminate in a distinct parastyle (Plate 7).

OVERVIEW

Proceeding to the lower dentition, the Taung type specimen shows some distinctive peculiarities. Even though it is worn, the rather ovoid Rdm 2 shows evidence of twinned mesial basins, the anterior lying in front of the bases of the protoconid and the metaconid, and the other just behind it. This tooth also has a laterally compressed mctaconid and entoconid, and a groove and a conulid between the entoconid and the buccally placed hypoconulid. The M i s are also somewhat ovoid, and have a thick paracristid lying in front of a trigonid basin that nestles between the bases of the of the protoconid and mctaconid. There is a vertical notch between the protoconid and the hypoconid, a cristid between the mctaconid and entoconid and a small conulid between the entoconid and the somewhat centrally placed and mesiolingually skewed hypoconulid. The larger metaconid is longer m/d than the protoconid, and the hypoconid broadly contacts the metaconid. T h e enamel is thickly crenulated. The morphology of its lower dm2 aligns Taung with the Swartkrans fossils SK 61, 62, 64 and 3978, and with the Kromdraai specimens KB 5503 and TM 1604 (Plate 8). Although very worn and somewhat damaged, the last of these retains evidence of the twinned basins. It is also possible that the isolated lower Rdm2 KNM-KP 31729 from Kanapoi fits in this morph by virtue of its "twin-basin" mesial morphology. T h e relatively unworn dmls of SK 64 and 3978 show that in this morph the d m l is relatively small and narrow, slightly mesially tapering, and has a very m/d short talonid that lies lower than the larger trigonid. The metaconid and protoconid lie opposite one another, their bases abutting in the midline ot the tooth, and a thick paracristid runs down from the apex of the protoconid and arcs around to the base ot the larger metaconid and up to its apex, enclosing a small and mesially facing trigonid basin. The entoconid and hypoconid are large and somewhat conical, and the hypoconulid is lower, of moderate size and centrally placed. The lower M l of Taung has a thick paracristid that runs directly in front of the metacone and protocone, which lie opposite one another and whose bases contact in the midline of the tooth. In between the paracristid and these cusps lies a small trigonid basin. The well-delineated hypoconid and the slightly large entoconid lie opposite one another, the base ot the hypoconid cutting in front of the entoconid base in the midline of the tooth to contact the metaconid. The moderate hypoconulid is separated from the

HOMIN'ID G U A N I O D E N T A L M O K IMI O LOU 1 ES I A N O V E R V I E W

hypoconid by a distinct notch, and thus appears to distend the tooth distally and slightly buccally. The axis of the hvpoconulid is oriented distobuccally, but the cusp lies in the midline of the tooth. The apex of the hypoconulid contacts the distal side of the entoconid. A small but distinct conulid lies between the hypoconulid and the entoconid. The enamel is deeply and thickly crenulated, and there is a deep vertical groove between the protoconid and the slightly smaller hvpoconid. The unerupted M l of SK 61 is quite similar to the M l of Taung, differing primarily in the degree of crenulation, in the development of a more wedge-shaped basin between the protoconid and the metaconid, and in having a thickened cingulid low down between the bases of the protoconid and hvpoconid. Additionally, the hypoconulid does not distend the tooth as much. Finding exact rather than gestalt matches for Taung in adult lower dentitions from other sites is not easy, partly at least since the various South African australopiths appear to have remained remarkably primitive in their lower dental morphologies, and because there is only one permanent lower molar to compare, precisely the one that is most likely to be heavily worn in adult specimens. Consider the following: T M 1517b and 1600a/b/c, S K W 5, SK 1587 and 1588, Sts 52b and M L D 18 share the following lower dental morphology of M 1 - M 2 where preserved (Plate 9). O n M l the hypoconid is wedge-shaped, and crosses the midline to contact both the metaconid and the entoconid. T h e entoconid is truncated internally. T h e hypoconulid has a long contact with the hvpoconid and a moderate contact with the entoconid. O n M 2 the hypoconid is thick m/d and squared-off internally, and has a broad contact with the entoconid and some contact with the metaconid. O n some specimens the hypoconulid is wedge-shaped and has a long contact with the hvpoconid while just touching the entoconid. There may be a conulid between this wedge-shaped hypoconulid and the entoconid. In other specimens, such as SK 6 and 843, the M l morphology is as just described, but although it has a squared-up hypoconid the M2 differs in presenting a b/1 much narrower entoconid. A groove that runs along the distal side ot the hypoconid and extends to the distal side of the entoconid delineates a hypoconulid that is not very long m/d but that spans the distal end of the tooth. SK 6 preserves a R M 3 that differs from the M 2 in having a less b/1 wide but m/d somewhat longer hypoconulid, and the worn M 3 of StVV 404 shows

477

intercuspal grooves that are similar in pattern. The M 3 of SKW 5 is long and distally tapering, the lingual side being essentially a thickened continuous edge with little or no distinction between the metaconid and the entoconid. The thick, squared-up hypoconid runs across the tooth to contact this lingual edge. Distal to the hypoconid, the hypoconulid region extends fully across the distal end of the tooth and is subdivided by grooves. Although distally broader and more rounded, the M 3 of T M 1517b is basically similar to that of SKW 5. O n both, the hypoconid is very long m/d and internally squared-off, the metaconids are obliquely compressed and the distal regions are subdividend into three components. These two specimens are also similar in P2 morphology, particularly in the presence of a very thick postcingulum that terminates in a stylid on the side of the protoconid, and in showing little indication of a postcingulid. The P2s are also quite wide b/1 compared to the M i s . The P I of T M 1517b is relatively larger than that of SKW 5, but is of reasonably similar shape. The M 3 of Sts 52b differs in having a very distinct paracristid that runs low on the crown across its mesial side. A large, tall and m/d very long metaconid is separated from a small entoconid by a groove. The distinct hvpoconulid is quite buccally placed and separated from the entoconid by a moderately sized and leds:e-like structure. T h e premolars differ from those of T M 1517b and S t W 5 in being relatively narrower b/1, having more internally-placed metaconids and protoconids and in having a thick rather than a thin postcingulum. It is impossible to say with confidence whether, despite the various minor differences noted, more than one basic morph is represented among the materials just described—although, for example, the premolar differences between SKW 5 and Sts 52b appear substantial. Further, since the only permanent tooth of Taung is the M l , and this tooth is heavily worn in all adult specimens appropriate for comparison, it is not possible, despite a general overall similarity, to determine whether or where Taung belongs within this assemblage. Our feeling is thus that it is premature at present to attempt to delineate a specifically Taung morph on lower dental evidence. The Makapansgat specimen M L D 2, a juvenile mandible with R and L P l s and M 1 - M 2 , R worn dm2s and LP2 erupting, shows premolars with spiky and mesially shifted metaconids, long and laterally compressed protoconids, and grooves separating the paracristids from the bases of the metaconids. There

478

IIOMIN'ID C R A X I O D E N T A L

M ORPHOLOC31 ESI A x

are also marked but low postcingulids. The M i s are slightly smaller than the M2s, but they are similar in being bulky, roundcdly rectangular teeth with thick cingulids that run completely around the bases of the protoconids, wedge-shaped trigonid basins between the protoconid and mctaconid bases, wedge-shaped hypoconids that contact the bases of the metaconids and the entoconids and large wedge-shaped and centrally placed hypoconulids. St\V 404 from Sterkfontein has R P 2 - M 2 , all very worn, and a supposedly associated M 3 . T h e PI is large and similar in shape to its counterpart in M L D 2, and it also has a groove between the mctaconid and the paracristid. Both appear to represent the same distinctive morph (Plate 10). SKx 4446, a partial R mandible with P 2 - M 2 originally ascribed to the genus Homo, has a P2 that is unique in that the protoconid is encircled from its mesial to its buccal side by a very thick crest, from which it is delineated by a deep groove all around. The M 2 is roundedly triangular, with wedge-shaped hypoconids that contact the bases of the metaconids and entoconids in the midline of the crown, and spikclike, compressed hypoconulids that are buccally placed and extend mesiolingually toward the entoconid. An m/d long and fairly wide shelf lies in the distolingual part of the tooth between the entoconid and the hypoconulid. Although the M 2 is somewhat damaged, the protoconid, hypoconid and hypoconulid are pointed cusps. The M i s of SK 55b and T M 1536 are similar to their counterpart in SKx 4446; they are less worn and their cusps are pointed. The M 2 of SK 55b is also similar in comparable regions to the M 2 of SKx 4446; the lingual parts of this tooth are compressed and form a continuous edge, while the buccal cusps remain pointed and are peripherally placed. The broad and long talonid basin is finely cuspulated. The M 3 of SK 55b is distinctive in that virtually all of its cusps are indistinct and incorporated into a crest that encircles a broad, long and finely cuspulated basin. This tooth is matched by the M 3 of StW 278, which seems to be the lower counterpart to StW 277, an upper M 3 that is characterized by continuous cresting that encloses large and finely cuspulated talon and trigon basins (Plate 11). StW 277-like morphology may also be found at Kromdraai in the incompletely developed molar crown KB 5383, an association that may provide a link between the upper and lower dental morphs concerned. This compressed cusp configuration, with continuous cresting around m/d long basins in both upper

OVERVIEW

and lower molars, is echoed in certain teeth from eastern Africa, such as Hadar AL 333x-l, Omo L50-2 and Kanapoi KNM-KP 34725T (Plate 12). Th similarities certainly warrant further investigation* but at this point it is not entirely clear that this morph is properly regarded as hominid. The lower M i s of StW 151 are distinctive. These teeth are long, narrow and ovoid, with angular pointed and well-delineated cusps, the metaconid being the most pronounced among them. They have a very narrow and deep notch between the bases of the protoconid and metaconid. The entoconid is somewhat laterally compressed, and the hypoconulid is buccally placed and its distolingual side slopes steeply, creating a notch between it and the entoconid. A similar configuration is seen on the LM1 and the RM2 of StW 14, but the M 3 of the latter does not reflect this morphology at all, instead looking like the M 3 of Sts 52b (raising the question of whether it is properly associated). Another distinctive lower dental morph is best represented by the Swartkrans specimen SK 25, a fragmentary mandible with unworn L and RP2-M2. The P2s are very large relative to the M i s and their surfaces are very wrinkled. A small, deep anterior fovea is present on this tooth, together with a larger posterior fovea, also deep. A short cristid runs down from the protoconid around to the base of the very mesial metaconid, the distal side of which is separated from a very thick cristid by a groove. This cristid runs around to the side of the protoconid, from which it i^ also delineated by a groove. M 1 - M 2 are ovoid, with a thin, creaselike basin set well back on the occlusal surface between the bases of the protoconid and the metaconid. O n both molars the metaconid is slightly larger than the protoconid, and the buccally placed hypoconulid extends mesiolingually to the entoconid. from which it is separated by a large, wedge-shaped and distolingually placed conulid. M 1 - M 2 also have a small, shelflike cingulid low down between the bases of the protoconid and hypoconid, and between the hypoconid and the hypoconulid. In both teeth a long, sinuous groove runs along the m/d midline ot the crown. The cusps are all bulbous and poorly separated. They are quite internally placed, so that the centr.il basin or groove is long and thin. In contrast, the central basin in Taung is wide open, and the apices of the well-differentiated cusps arc peripherally placed. Similar morphologies to SK 25 are seen in the mandible SKW 5, and were probably originally present in the

II O M I N I D C R A N I O D E N T A E , M O R P H O L O G I E S : A N O V E R V I E W specimens SK 15,23, 74a and 81 (Plate 13). In SK 23 the preserved P I is substantially smaller than the P2, and the narrow, tapering M 3 of this specimen bears a particularly well-marked central longitudinal groove. In SK 15, the holotype of Teianthropus capensis, the relatively unworn M 3 shares the tapering occlusal outline and longitudinal groove with SK 23 and SKW 5 (which also confirms that cusp disposition on M 3 is essentially similar to that on M2), while the mesial interstitial wear facet on the L M l extends fully across the tooth, strongly suggesting that the P2 anterior to it had been quite broad. These striking resemblances suggest that SK 23 and 25, and the smaller SK 15, respectively represent male and female of the same form, in which, as judged from SK 23, the anterior teeth (and especially the canine) were tiny. In contrast to the variety of specimens from Swartkrans that might be compared in the lower dentition to Taung, SK 6, the partial mandible that is the holotype of Paranthropiis crassidens, is decidedly distinctive. This specimen, a partial left mandible with associated R teeth, has elongated lower molars, with ovoid M 1 - M 2 and a distally tapering M 3 . All three lower molars have or had a small, wedge-shaped notch between the bases of the protoconid and metaconid. These cusps are of equal size and lie opposite each other on M 2 - M 3 , while in M l the protoconid is smaller and thus the metaconid seems longer m/d. On M l the wedge-shaped hypoconid contacts both the metaconid and the entoconid; on M 2 - M 3 the hypoconid is thicker m/d and makes a broad contact with the entoconid. O n M 2 - M 3 the hypoconulid is wide b/1 and extends more buccally than lingually. Its surface bears some grooves, which were probably also originally present on the worn M l . O n the M 2 alone, there is a protostylid. As seen on the L, the P 1 - P 2 are subequal in size, and are small relative to the M l . On P2 the protoconid is centrally placed and the metaconid lies very mesial to it. Thick cristids run from the metaconid to the sides of the protoconid. In this brief survey of the hominid fossils from the central South African sites we have been able to do no more than raise a number of issues that we feel it will be important to address in future studies of the South African australopiths. In particular, it will be necessary to reevaluate the fossil records of each of these sites with respect to the type australopith from Taung, and to move away from the "gracile vs. robust" paradigm that has dominated the study of these hominids since the days of Robert Broom. It is already becoming clear

479

that multiple hominid morphs are present at most of these sites, and that most such morphs may be detected at multiple sites. The groupings we suggest here must be regarded as preliminary, since the process of sorting the many specimens involved into morphs has been fraught with difficulties, particularly where lower dentitions are concerned. Such difficulties do not arise simply because many of the dentitions available arc heavily worn, but because the morphs themselves appear to be inhcrendy problematic to recognize. The main reason for this is that the record is overwhelmingly a dental one, and that dentally (and apparendy particularly in their lower dental morphology), the South African australopiths seem in general to have remained remarkably conservative. We must also note that various morphologies represented at South African sites echo some that are seen at sites in eastern Africa. Thus, for example, the upper molars of the SK 48 morph are more similar to those in the Kenyan specimen KNM-WT 17400 than they are to South African fossils such as T M 1517a or StW 252. Such resemblances warrant much closer attention than they have so far received.

EASTERN AFRICA: THE "ROBUSTS" Essentially, the study of australopiths in eastern Africa began at Olduvai Gorge, with the cranium O H 5. This individual differered in numerous ways from the South African "robusts"; nonetheless, largely on the basis of its reduced anterior and enormous posterior dentitions, it was classified with them as a "hyperrobust" East African variant. The face of O H 5 is relatively flat, but differs from South African Paranthropiis such as the classic exemplar SK 48 in being very tall and relatively narrow, and in having an extraordinarily deep nasoalvcolar clivus extending below a "hammocked" subnasal region (Plate 14). In addition the orbits arc tall, ovoid and high-set, and they lie below superior orbital margins that are tall s/i and that arc around each orbital opening. The nasion is set high, so that the nasal bones extend much farther superiorly than in SK 48. The anterior root of the zygomatic arch arises high above the alveolar margin. The great depth of the face of O H 5 caused some retrospective puzzlement when the putatively matching Pcninj mandible was discovered, with its low rami. However, with the recovery of the KNM-ER 406 cranium from East Turkana, this

4S0

HOMINID CRANIODENTAL M O R P H O L O G I E S : AN

apparent inconsistency could be written off as "variation." For ER 406 much more strongly resembled the South African specimen than O H 5 did in having a shorter face and, particularly, subnasal region, and in having wider orbits with thin and much less arcuate superior margins and a low nasion. Most strikingly, the Swartkrans and Turkana specimens shared a striking broadness of the face relative to its depth, the opposite of what was seen in O H 5 . Add to this the presence in all the "robusts" of a diminished anterior dentition (frequendy due at least partly to heavy wear), in conjunction with a substantial expansion of cheek-tooth surface area, and in an era of inclusivity the growing record made it relatively easy to see the eastern and southern African specimens as local variations on the same theme, namely what is now generally known as Paranthropus. At the same time, following the recognition of Homo babilis at Olduvai, it became possible to regard more "gracile" forms from East Africa as Homo., even as the South African "graciles" continued to be seen as australopiths. Forty years on, it is possible to see that this relatively straightforward schema obscures real morphological complexities. The recovery of the ER 23000 frontal from East Turkana, for example, suggests that the distinctive supraorbital morphology of O H 5, rather than being anomalous, may in fact indicate that these two specimens belong to a consistent and readily distinguishable eastern African morph (Plate 14). This distinctive entity differs morphologically from all of the members of a larger and clearly subdivisible clade that is represented in southern and eastern Africa by forms such as SK 48 and ER 406, respectively. T h e somewhat earlier "Black Skull," K N M - W T 17000, with which can be associated the edentulous maxilla KNM-ER 405, also belongs to this larger grouping. Interestingly, W T 17000 is more similar to southern African forms such as SK 48 than to other eastern African australopiths in having distinctively s/i thin supraorbital margins, an apparently derived state in comparison to the thicker supraorbital margins of other early hominids. Similarly, W T 17000 and SK 48 share a fiat cranial profile behind the supraorbital margins, a feature that is absent in virtually all other australopiths. The hemicranium KNM-ER 732, on the other hand, appears to be appropriately regarded as a female of the species represented by ER 406, given that it shows a relatively broad, flat and shallow face in combination with thin supraorbital margins surmounting rather wide and low-set orbits (sec Plate 14).

OVERVIEW

In the Chesowanja partial cranium the anterior root of the zygomatic arch arises low down and the nasoalveolar clivus is relatively short. Both of these characters distinguish this specimen from O H 5. The molar teeth of Chesowanja are unusual compared to those of both SK 48 and O H 5 in showing a very thick postcingulum that runs lingually around the hypocone and becomes longer m/d in the sequence M 1 - M 3 , and a posterior decrease in the size of the hypocone. The damaged cranium KNM-WT 17400 usually allocated to P. boisei, is dentally similar to SK 48 and O H 5 in having tiny upper anterior teeth, especially the canines, and premolars that are relatively large compared to the molars (see Plate 6). In the molars of W T 17400, as in the SK 48 morph, both protocristae are well developed and encircle the paracone, and the large hypocone is compressed m/d but quite wide b/1. As in both O H 5 and SK 48, M l is the smallest of the upper molars, M 3 is quite large, and the metacone decreases in size in the scries M 1 - M 3 . T h e way in which the face of W T 17400 is damaged makes it appear narrow, but this may not originally have been the case; and in preserved features this specimen aligns with the general SK 48 clade. Such features include a s/i short subnasal region and a low-lying nasion. Additionally, the infraorbital foramen lies far below the inferior orbital margin, and on the R the well-preserved infraorbital margin indicates that the orbit had originally been wide. In cranial and upper dental characteristics, then, the general affinities of the preponderance of the East African "robust" materials appear to lie with a diverse and widely distributed clade exemplified by the Swartkrans specimen SK 48, while there appears in addition to have existed in East Africa a local morph, without southern African tics, that is exemplified by O H 5 and the ER 23000 frontal. An entire larger SK 4 8 - O H 5 morphological grouping (that apparently excludes W T 17400) docs seem to be united by a suite of dental characters that includes an M l that is relatively small compared to the subequal M 2 - M 3 and is (like the M2) m/d short, while the molar mctaconcs decrease in the sequence M 1 - M 3 . We are unable to surmise where reported Middle Awash materials such as the Konso cranium fit into this picture, while the isolated upper teeth from O m o do not closely compare with any other known hominid teeth. T h e maxillary fragment from Malcma, in Malawi, offers insufficient morphology to allow helpful comparisons.

l l n M I N M O G l l A N I O h K N T A I . M O HP II U l . O O I KM? A N O V K U V I K W

The IVninj lower jaw has historically been taken AS the classic /? bohti mandible, though it unfortunately lacks detailed morphology on all teeth except the M3s. The canines arc m/d narrow, aiul the anterior teeth occupy a narrow space at the front of the jaw although the incisors were probably tall-crowned. The PI is small m/d compared to the P2, which has a distinct and enlarged enroconid and is large relative to the M l and even wider b/1. The molars increase in size posteriorly, and M I - M 2 were probably rounded ly rectangular, as is the M3. This latter tooth probably did not have very well-differentiated cusps. The hvpoconid does not extend across the midline, and the b/1 wide and m/d long, shelflikc hypoconulid region is somewhat d/l-oriented. There is still evidence of heavy crown crcnulation, and there is a distinct buccal cingulid on the protoconid as well as on the hvpoconid. M 1 - M 2 may have had mctastylids. The many "robust" mandibles from East Turkana include multiple dental morphologies. Those teeth preserved in KNM-ER 729a from East Turkana arc cither broken, worn and/or weathered. As in Pcninj the PI is quite small relative to the P2, which has a thick postcingulid that swells into a relatively large entoconid. Unlike that of Pcninj, however, the M l was small relative to the larger and subequal M 2 - M 3 , and it appears that M 1 - M 2 tapered distally, as docs the M 3 , which is notable in being very b/l wide mesially. The hypoconulid region is smaller than in Pcninj, and is centrally placed. ER 1477a is a mandible with deciduous teeth, plus an M l visible in its crypt that is not compatible with cither the Pcninj or the ER 729a M3s. ER 3230 resembles 729a and Peninj in having a relatively small P I and a much larger P2 with a thick postcingulid and a large entoconid region; however, the molars arc much narrower b/1 and the morphology of its M 3 is nothing like those of Peninj or ER 729a M 3 , and its M l is not comparable to that of ER 1477a. ER 15930 docs not appear to have had as large a P2 as Peninj, ER 729a or ER 3230; and while its molars are relatively long and narrow, as in ER 3230, the relatively unworn M 3 is ovoid in shape, and tapers markedly distally. It is distinguished from the M3s of the other mandibles mentioned by having relatively tall cusps, a long, deep talonid basin, and a distinct, centrally located and b/1 narrow hypoconulid. Conversely, ER 1820, a R mandibular fragment with d m 2 - M l , may represent the same morph as ER 15930. T h e M l of ER 1820 is narrowly ovoid; its cusps are tall with a long, deep

'IS I

talonid basin between them, and it has a small but distinct and centrally placed hypoconulid (Plate 15), Two isolated U and L lower molars, together KMN-KR 15940, also differ from other East Turkana specimens in being more subcircular, with poorly defined cusps that arc compressed and almost form a ring around the broad talonid basin. In many ways they are reminiscent of some lower molars from Omo, e.g., 1,628-3 and 1.795-1, from which they differ in having m/d longer and more mesially arcuate trigonid basins, m/d longer but b/1 narrower hypoconids and larger and less b/l compressed cntoconids. A few "robust" mandibles ami lower dental specimens have also been reported from West Turkana deposits. The M l in W T 16006 was probably roundedly rectangular, as was M2 and as is M3. Only the M3 of this specimen preserves all of its morphology; it resembles ER 3230 in having an m/d long and welldeveloped paracristid, but the protoconid and especially metaconid are much larger, and the protoconid bears a complete cingulid buccally. W T 8556 differs from all the mandibles mentioned in having very distinct and wcll-dclineatcd cusps on its premolars and M l ; its P i is obliquely truncated lingually, producing a subtriangular tooth that contrasts in shape with the more rectangular Pis of all East Turkana specimens. A number of "robust" mandibles and isolated teeth arc additionally known from the lower Omo Wiley of Ethiopia. The most complete of them, Omo L7-A125, a massive but shallow corpus with worn and damaged teeth, offers little useful detail. However, it differs from all East Turkana jaws in that the anterior teeth are contained in a much more restricted space, the large P2 is much wider b/1 and narrower m/d, and the M3 was large and subcircular, as also probably were M 1 - M 2 . The buccally placed M 3 hypoconulid is small, and a large, wedge-shaped conulid lies between it and the entoconid. Other cusp detail is essentially obliterated, but the general shape of this tooth is unlike the M3 of the Pcninj mandible or any of the Turkana specimens. Isolated Omo lower molars that may belong to the same morph include L628-23 and L795-1. It is also worth noting that some isolated lower molars from South Africa, c.g., Kromdraai KB 5223, show certain similarities to these teeth, particularly in the shape of the hypoconulid and its contact with the entoconid, and in the presence of a very well-developed distol.ngual shelf. Omo 18-67-18, the tyP c o f Paraustralofttfoecus actbkpkm, preserves no teeth at all but appears to have been similar to L7-A-125 in having anterior

482

IIOMINID CRANIODKNTAL

M o u i M i o L O d i E s : A N O V E R V I E•;\v

teeth that were confined to a restricted space at the front of the jaw. Since this specimen does not preserve any usable morphology, it is clearly indequate as a holotypc. Given the emerging complexity of the "robust" record, there is certainly no evident reason other than their pcnccontcmporancity for associating the O m o 18-67-18 and K N M - W T 17000 specimens, as has regularly been done for some years now for purposes of classificatory convenience. If it is desired to classify the Black Skull in its own species, the available name is Australopithecus ivalkeri (Ferguson, 1989). There is a substantial collection of mandibular fragments and isolated teeth from the lower O m o Valley that may not belong with the "robust" group, but that should be mentioned briefly here. At least three lower dental morphs appear to be represented among these specimens. T h e mandibular corpus fragment O m o L-74-A21 is relatively tall and narrow m/1. It preserves a C and a P2. The P2 differs from that in L7-A-125 in being longer m/d than it is wide b/1, and it possesses a large talonid basin that is enclosed by a moderate and compressed entoconid that is joined by a crest that runs back from the protoconid. A low paracristid runs between the bases of the large metaconid and much larger protoconid, and there is a distinct cingulid around the base of the distal cristid. These morphologies distinguish this tooth from any of the Turkana lower P2s. T h e unworn isolated R lower P2s L51-79 and L51-80 do, however, match the premolar in L7-A-74, adding the information that in this morph the enamel surface was finely crenulatcd, and that the entoconid is not a distinct cusp, but that its region is filled out by a thick postcingulid as it flexes to run to the lingual side of the metaconid. This confirms that what looks like a large metaconid in L7-A-74 is an artifact of wear. T h e mandibular fragment L427-7 contains P 1 - P 2 and M 2 . T h e P2 generally resembles that of L7-A-125, but the postcingulid is much more extensive, and squares up the d/1 corner of the tooth. This P2 postcingulid morphology is also seen in the partial mandible L75-1969-14a. In this latter specimen the postcingulid is heavily creased, but otherwise it has the hallmarks of the same morph. T h e M 2 of L427-7 is broadly ovoid, with somewhat peripheral and compressed lingual cusps, and buccal cusps that arc somewhat internal though also compressed. T h e long talonid basin between them is relatively shallow and runs down the midline of the tooth. T h e enamel of the basin is deeply crenulatcd, as is the very m/d long

paracristid that lies internally between the bases of h protoconid and the m/d long metaconid. What * * pears to be the hypoconulid is quite buccally pla«S" and its base is obliquely oriented m/1 and contacts^! ' entoconid. The M2 of L75-1969-14a is similar \ shape to that of L427-7, and still bears evidence of extensive crcnulation. The mandible fragment L8-60-2 bears very worn premolars and molars that resemble in outline those of L427-7. There are al three isolated lower molars from Omo (L628-9 L628-10 and K7-69-19) that could be associated with the L427-7 morphology, which especially in the disposition of the hypoconulid recalls specimens from South Africa belonging to the T M 1517b/SKW 5 morph. Oddly, the morphologies of the lower Pis of L75-1969-14a and L427-7 are not closely comparable. O m o 221 and 227, partial juvenile mandibles, retain d m l s and dm2s. In general outline, the intensity and kind of wrinkling, the disposition of the shclflikc paracristids and the inward orientation of the rather buccally placed hypoconulids, the dm2s of these specimens arc very similar to the M2 of L427-7, suggesting that all belong to the same morph.

OTHER AUSTRALOPITHS AUSTRALOPITHECUS ANAMENSIS A s currently recognized, the hypodigm of the species Australopithecus anamensis contains materials from the Allia Bay and Kanapoi localities lying low in the sedimentary sequence of the Turkana Basin. Our own preliminary survey of these fossil assemblages suggests that more than one morph may be represented among the materials assigned to A. anamensis. The Kanapoi holotypc, K N M - K P 29281A, consists of L and R mandibular corpora with all teeth present but worn. As noted earlier, the degree of dental wear in this specimen make it less than ideal as a type, but in the descriptive entry here wc have identified a suite or fossils from both Kanapoi and Allia Bay that appear to fit comfortably with it in the same species. Where all these morphologies are preserved, such specimens, exemplified at Kanapoi by KNM-KP 29287A/B and KP 30500F and at Allia Bay by KNM-ER 20428 and 20432A, show noticeable lower premolar hctcrodonty, with the tall, pointed PI dominated by a large, centrally placed protoconid bearing a vertical cre;>t

HoMi.vin CuANiontNTAL M o i u ' i i o L o o i t s : A N O V E K V I K W hngually. This tooth also has a fairly large distal basin that is surrounded by an unadorned crest, and a small, vertically oriented and Hnguallv facing mesial fovea. i n c lingual side is obliquely truncated, producing a broadly triangular outline. P2 is more roundedly rectangular, primitively bearing a distinct mctaconid that hes opposite the very forwardly placed protoconid. The mesial ends of the molars arc straight across, and are roundedly broad distally, with distinct buccal cingulids throughout. The talonid is generally emphasized over the rather small trigonid. Several other hominid morphs can be identified at Kanapoi and Allia Bay. One of these, interestingly, is most closely comparable to the A. afaremis holotypc LH4, from Lactoli. KP 292S6C is a lower LM1 that exhibits a pair of deep, wide and somewhat b/1oriented pits on either side of the centrally placed but poorly delineated hypoconulid. This distinctive morphology is echoed in the worn A13 of L H 4 (Plate 16). In addition, there is found at both Kanapoi (e.g., KP 30502D and E, KP 31712 J and KP 29286 D and^I) and AIHa Bay (ER 20422 and 30201) a morph that may also be represented at Melka Konture (AIK 81 GAR IV 2) (Plate 17). Some of the similarities among these teeth are also seen in the distal regions of the Ails of the juvenile Laetoli mandible L H 2 . These similarities include a notch buccal to the hypoconulid and a groove lingual to this cusp, and may be features indicative of membership in a larger grouping. However, it should be noted that the preserved dm2 of L H 2 is quite different from that in the Melka Konture specimen. Beyond these morphs, the Kanapoi specimens KP 34725 G and T, upper and lower molars, are characterized by extensive cuspulation within very broad basins that are surrounded by a cresting system that rings the crown with indistinct cusps. This same basic morphology is also found at "early hominid" sites as distant as Sterkfontein, O m o and Hadar. It is not possible usefully to compare any Kanapoi or Allia Bay materials with the enigmatic Lothagam mandibular fragment, K N M - L T 329, since in this latter specimen the teeth are too worn to interpret reliably; all that can be done is to exclude it from comparison with such specimens as the Hadar A L 400-la mandible because it has no notch between the M l hypoconid and hypoconulid, and with the Maka VP 1/12 jaw because it also lacks a deep hypoflcxid notch on that tooth (see discussion below). As noted earlier in this volume, there are several other distinctive hominid dental morphologies besides those

483

sketched above that can be recognized at the two "amwiensis" sites, and these will have to be dealt with in any comprehensive revision of these faunas.

AuSTRslLOPITUECUS/IFslRENSIS

Australopithecus afaremis was described on the basis of materials from both Hadar in Ethiopia and Laetoli in Tanzania (the type materials coming from the latter site, despite the name). Early debate centered on whether more than one hominid species was represented in this large suite of materials, but a consensus quite rapidly developed that the fossil sample, while varying substantially in size, was sufficiently uniform morphologically to be subsumed into a single species. There are, however, some morphological indications that a greater taxic variety than this scheme admits is present in these Ethiopian and Tanzanian assemblages. The LH4 holotypc mandible of A. afaremis (Plate 18) is broad and straight across the front of the jaw; and although the premolars arc hctcromorphic, both are very narrow b/1 relative to the width of the M l . The P I is slighdy wider b/1 and noticeably longer m/d than the P2. The PI is dominated by the protoconid, from which a thick, short and horizontally oriented crest runs Hngually to swell at its terminus high up on the tooth. Distally, this crest encloses a relatively deep and upwardly oriented mesial fovea that lies high on the crown. Distal to this crest is a tall, fairly m/d long, shallow, vertically oriented and Hngually facing fovea. The PI is Hngually truncated, producing a long and mcsially tapering and thus subtriangular outline. The P2 is straight on its Ungual side and more clearly rounded on its buccal side. M 1 - M 2 were originally probably of the same roundedly rectangular outline exhibited by the M3, which additionally shows twinned wide and deep pits flanking the centrally placed but indistinct hypoconulid (as also in Kanapoi KNM-KP 29286C). These pits are placed somewhat in from the edge of the tooth. The LH2 juvenile mandible preserves the Mis, which are different in both outline and cusp configuration from what can be discerned on the M l of LH 4 (Plate 18). In particular, L H 4 has a distinct vertical notch separating the m/d elongate hypoconid from the centrally placed and welldclineatcd hypoconuHd. There is a horizontal groove lingual to the hypoconid, as in LH4, but unlike in the latter There is no buccal groove. The dml of LH2 is unusual, though it is matched by that of LH3q. It is much smaller than the dm2 in all dimensions, has only a very small talonid basin and lacks a trigonid basin altogether.

484

HOMINID CRAXIODENTAI. M O R P H O L O G I E S : AN

LH21a is a partial palate with two deciduous molars and M l erupting (Plate 19). In all three teeth both protocristae are thin but well developed, and distinctlv delineate a relatively wide, broad and deep trigon basin. Even better developed is the posteingulum, which arcs distally and then back into the protocone, enclosing a large, moderately deep and well-defined talon basin that is bounded mesially by a moderately developed postprotocrista that runs directly from the protocone to the metaconc. This morphology is matched at Olduvai Gorge by the isolated upper M l of O H 6. LH6e is an upper dm2 or M l , but does not resemble either of these teeth in LH21a, thereby establishing heterogeneity in the Laetoli hominid upper dental sample. LH3h (an upper M l ) matches LH6e fairly well, especially in the configuration of the postcingulum and hypocone, the orientation of the preprotocrista and the separation of the hypocone and protocone by a notch (Plate 19). LH3a (an upper Rdm2) similarly matches LH6e. However, L H 3 t (a lower probable M l ) is distinctly different from LH21a. This provides additional confirmation of heterogeneity in the sample. Finally, although there is little left of the morphology of the assembled upper too throw catalogued as L H 5 , the molar outlines of this specimen suggest no particular similarity to either of the morphs just discussed. The distinctive morphologies of the LH.4A. afarensis holotype are notably lacking in mandibular dentitions from Hadar. Particularly, the AL 288-1 "Lucy" lower jaw differs from L H 4 in numerous characters. Its premolars are about as wide as the M l , hence not narrow b/1 as in LH4; the P i is not obliquely truncated lingually, and the crest emanating from the protoconid descends steeply down the lingual side of the tooth, delineating a small, vertically oriented and lingually facing mesial fovea and a large, distally facing distal fovea. The P2 of A L 288-1 is shorter m/d than that of LH4, and also differs in being broadly rounded lingually and m/d shorter buccally than lingually. Even though the M l of AL 288-1 is worn, this tooth did not possess the twinned pits flanking the hypoconulid, structures that were also absent on the M2 and M 3 . Indeed, while the lower molar morphology of L H 4 is very distinctive (though represented at Kanapoi as well as at Laetoli), that of AL 288-1 is more unusual; notably, the protoconid and metaconid lie far forward on the molar crowns, almost forming a loph, while the whole talonid is affected by a profusion of creases and wrinkles that

OVERVIEW

almost obliterate cusp morphology (Plates 20, 23) TV curious molar crown conformation is apparently not a individual idiosyncracy of AL 2S8-1, since it is replicated in two isolated and relatively unworn lower RMu from Hadar, AL-333\v-4S and 200-lb. A species name exists for this morph, should it be considered usefulAustralopithecus antiquus (Ferguson, 1984). The AL 417-lb morph that embraces the AL 2881 mandible is evidently the predominant lower dental morph in the Hadar hominid assemblage. However it is apparently not the only one. As we have pointed out in our preamble to the morphological descriptions in the Hadar entry, it has been difficult to make sense of the morphological variety seen in fossils from this collecting area. It might, for instance, be possible to envisage a morphoclinc in premolar morphology among Hadar lower dentitions, of the kind that substantia] individual variation within a single population might be expected to produce; but possible continuous variation in lower dental morphology is contradicted by molar form, which suggests that several discrete lower dental morphs can be distinguished in the large Hadar sample. The same conclusion applies in regard to upper molar morphs of which, again, the one represented by A L 417-lb appears to be preponderant. The various upper and lower dental morphs that we have provisionally recognized from this area are characterized in the Hadar entry in this volume. Away from Hadar, the upper dental morphology exemplified by A L 417-lc/d and A L 200-la appears to be most closely matched by the palate from the Bouri Fm (BOU-VP-12/130) in the Middle Awash published by Asfaw ct al. (1999) as Australopithecus garhi, and which we are able to evaluate only from published photographs (e.g., Locke, 1999). For example, both fossils possess robustly ovoid premolars with widely separated paraconcs and protoconcs. On the molars, both have a distally truncated metaconc, above which the postcingulum emerges, expanding as it runs to the distal side of the hypocone. The molars of A. garhi appear to be shorter m/d and the M 3 postcingulum to be less cuspulated than those of AL 417-1 and 200-la, but the basic structure of these teeth is similar in the two. It should also be noted that the maxilla A L 666-1 that comes from the top of the Hadar Fm and was assigned by its describers to Homo sp. quite closely resembles both //. garhi and specimens belonging to the morph exemplified by AL 417-lc/d and 200-la. The molars of AL 666-1 arc not as wide b/1 as those of AL 200-la, but both have tiny,

MOMINlh CltAMODENTAI, M o U I ' I I O L O G I B S : A.V OVERVIEW

rounded, low-crowned and shoveled I2s, and canines with very sharp and divergent mesial and distal edges and a thin but raised vertical crest coming down from the apex on the lingual side. Like those of the AL 200-la palate, the molars of AL 666-1 have distally truncated mctaconcs, a postcingulum that originates above the level of the mctaconc and expands as it runs to the hypoconc, and very mcsially shifted protoconcs (Plate 22). In its incisors and canine, AL 666-1 is thus more like BOU-VP-12/130 than like 200-la, but the hypoconc region in AL 666-1 is more m/d expansive than in BOU-VP-12/130 and the specimen is thus closer to AL 200-la in this feature. However, the three specimens together (with AL 200-la dentally representing at least a preponderance of comparable Hadar materials, although partly because of the presence of a diastema its palatal shape appears unusually long and narrow) appear to compose a cohesive group. The fossils from Maka, Belohdclic and Fcjej have all been allocated to A. afaremts. The most complete mandibular specimen from Maka is MAK VP 1/12, which is missing some anterior teeth and in which the teeth arc quite worn where preserved. This mandible is different from AL 400-la, especially in the shapes of the canines, which arc more b/1 compressed and are longer m/d. Additionally, its PI is less distended in its d/1 corner, and its very small mctaconid lies high up and close to the mctaconid; the P2 is more ovoid and elongate m/d, with more developed mesial and distal basins, and its mctaconid lies closer to the protoconid; and in the molars there is a distinct hypoflcxid notch that is deep on M l and becomes shallower posteriorly. The Maka specimen also lacks the notch between the hypoconid and hypoconulid that is especially marked in the M2 of AL 400-la. As concerns other Hadar specimens, the A L 288-1 mandible differs from MAK VP 1/12 in such features as having a PI that lacks a mctaconid and a roundedly subtriangular P2 with a less wcll-dcvclopcd mesial basin and a smaller and more lingually placed mctaconid. On M 1 - M 2 AL 288-1 has a protoconid that is larger than the mctaconid, whereas the reverse applies in MAK VP 1/12. Similarly, in A L 288-1 the distobuccal portions of the M 2 - M 3 arc distended, whereas in MAK VP 1/12 there is more emphasis on the distolingual side of the tooth. The isolated lower M2 MAK VP 1/4 is similar to the M2 of AL 400-la, especially in having a deep notch between the hypoconid and buccally placed hypoconulid, whose base angles b/1 to contact the

485

cntoconid (Plate 23). Nestled behind and in between the hypoconulid and the cntoconid is a fairly large and distinct conulid, as in AL 400-la and others like it. These specimens arc also similar in showing a cingulid between the bases of the protoconid and hypoconid and a small stylid-likc structure at the base of the notch between the hypoconid and hypoconulid. MAK VP 1/2 is a partial mandible with very worn and weathered M 1 - M 3 . Detailed morphology is lacking, but these arc long and b/1 narrow teeth that increase markedly in length from M l - M 3 . There is no trace of the hypoflcxid notch that is such a conspicuous feature of MAK VP 1/12, especially on the M l . Other differences include that the d/b portion of the M2 of MAK VP 1/2 is emphasized, whereas in MAK VP 1/12 it is the d/1 portion of the tooth that predominates. Again, in MAK VP 1/2 there is no notch between the M2 hypoconulid and hypoconid as there is in MAK VP 1/12. The teeth from Fcjcj arc mostly bereft of morphology, but the premolar FJ7A 58-2, a lower RP2, is barely worn. This smallish tooth, with a slender single root, resembles the P2 in MAK VP 1/12 in a variety of respects, including its subcircularity, the approximation of the wcll-dcvclopcd mctaconid with the slightly internally placed protoconid and the short, thick and distally arcuate postcingulid. Despite differences in wear, these two teeth can fairly confidently be referred to the same species. The partial Belohdclic frontal is not highly informative, but shows some differences in supraorbital conformation from the AL 444-2 cranium, generally viewed as the classic exemplar of A. afarensis cranial construction. It appears, for example, that posterior to the supraorbital region the frontal dome of Belohdclic may have been very much more restricted from side to side than that of the Hadar specimen, and that the area of its postorbital constriction was substantially more excavated (Plate 24). As reconstructed, AL 444-2 itself shows a cranial profile in which the frontal rises directly from the glabellar region, reaches its highest point above the auditory meatuses and then descends more steeply to the region of the superior nuchal line. Proportionally, most of the ncurocranium lies in front of the meatuses, with much less of its volume behind, and the nuchal plane is short and only moderately sloping. The orbits, as reconstructed in AL 444-2 and also as seen in the juvenile AL 333-105 and nartialy p c scrved in the adult AL 417-ld, are tall and ovoid,

486

I I O M I N I D C l l A N I O D K X T A l . M o i U M l O L O C i l ESJ A N

with a fairly narrow intcrorbital space between them. 1l i e s/i tail and m/1 broad zygoims are essentially vertical and forward-facing and, as indicated on the R, contribute to the more or less flat plane to which most ot the tace conforms across the zygomatic and orbital regions. This flatness is also seen in the AL 333-105 juvenile and in the adult lower faces AL 486-1, 333-1 and 417-Id. The anterior root of the zygomatic arch takes origin moderately above the level of M l . In profile the premaxilla is clearly flexed upward relative to the maxilla itself, and the entire toothrow describes a continuous arc. These features arc also seen in AL 4S6-1, 333-1 and 417-Id, as well as in the palate A L 200-la. In all these specimens, too, the long roots of the markedly heteromorphic incisors follow the general curvature of the nasoalveolar clivus. In AL 444-2 there is a distinct facial pillar rising above the canine root and proceeding up lateral to and to a point well above the inferior nasal margin. Similar pillars are also discernible in A L 200-la, 333-1, 486-1 and 417-ld; only in the last of these is the highest point of the pillar preserved, at about the level of the infraorbital foramen. In the skull base of AL 444-2, the huge and prominent mastoid process is particularly noticeable. Comparing these facial morphologies more widely, it is striking that the flatness of the mid- and upper faces appear to be a feature that links the Hadar forms with early hominids from sites throughout the African continent, including Koobi Fora, Lomekwi, Olduvai, Sterkfontein, Drimolen, Kromdraai, Swartkrans and Taung, and possibly also Bouri. If there is any one consistent feature uniting this entire group, this would seem to be it, though in some specimens it is exhibited in an ultraderived form, for instance, in the upward rotation of this flat surface in such forms as K N M - W T 17000 and O H 5. In general, the Hadar facial morphology seems to be matched elsewhere most closely by the D N H 7 cranium from Drimolen, at least to the extent that it also exhibits high-set and closely spaced, ovoid orbits, and an arced toothrow. The latter specimen does not, however, show facial pillars such as seen in the Hadar specimens, which are otherwise found principally in individuals known from the sites of Taung, Sterkfontein, Kromdraai and Makapansgat, and are interestingly not typical of other eastern African early hominids. Facial pillars are widely distributed among middle to late Miocene hominoids, and are reasonably regarded as primitive within the larger cladc. If loss of these structures is thus a derived trait within the eroup

OVEKVIKW

under scrutiny here, it is reasonable to ask whether its nondevelopmcnt in such forms as Drimolen, SK 48 and other Swartkrans fossils, OI1 5, ER 406/732 and VVT 17000 carries a phylogcnettc signal. Clearly, the various hominids that have been assigned to Australopithecus afarensis make a rather heterogeneous assemblage, the wider affinities of which demand further study. Perhaps most importantly the type specimen of this species, LH4, does not appear to have particularly close affinities with any of the fossils we have examined from I ladar. In contrast, specimens similar to L H 4 do appear to exist in the samples allocated to A. ana mens is. In this brief overview we have drawn attention to the variety (as well as uniformities) of hominid dental and other morphologies represented at the various sites that have yielded fossils allocated to A. afarensis. It is premature at this point to suggest drawing new txxonomic lines in this diverse collection of fossils, but it is an option that will ultimately require consideration. T h e notion that morphological heterogeneity exists in the Hadar sample echoes the early debate that faded with the general acceptance that size differences among the hominid fossils from the site, and notably among the postcranial remains, are attributable to substantial sexual dimorphism within a single species. Recently, Reno et al. (2003) have rejected this received wisdom, arguing that when the pattern of postcranial size variation shown by the specimens attributed to A. afarensis (including the large humerus and the proximal femur from Maka) is compared to the patterns shown by modern humans, chimpanzees and gorillas, A. afarensis emerges as most similar to the relatively nondimorphic Homo sapiens. It is clear, however, that the nature of sexual dimorphism among the Hadar hominids, a critical component of current functional and behavioral hypotheses, will have to remain an unresolved question until the systematic implications of the diverse dental morphologies we have described have been sorted out.

EARLY HOMO' The notion of "early Homo" ultimately descends from the creation by Louis Leakey and his colleagues of Homo habilis, almost forty years ago (Leakey, Tobias and Napier, 1964). This new species was erected to

IIoMiNin C R A N I O D K N T A L M O R P H O L O G I E S : A N O V E R V I E W accommodate the gracilc materials from the lower levels of Tanzania's Olduvai Gorge, in what was at the time a brave move, and one that was in hindsight necessary to break away from the constricting embrace of the then-prevailing linear and minimalistic view of human evolution. Nonetheless, it must be admitted that its creators' systematic judgment was heavily influenced by the perceived need to identify the maker of the Oldowan tools found in these sediments as a member of our own genus. This concern was directly generated by the then-current notion of "Man the Toolmaker," and it was clearly expressed in the name that Leakey and colleagues chose for their new species, which translates as "handv man." Morphologically, however, it has subsequently become clear that the argument for including these Olduvai specimens in an anatomically coherent genus Homo is weak, as indeed is that for regarding most "early Homo" as referable to the species H babilis (e.g., Wood, 1992; Wood and Collard, 1999; Tattersall and Schwartz, 2000). Our reappraisal of the Olduvai "gracile" collection for these volumes has additionally demonstrated that not all of the fossils from Olduvai Beds I and II that have at one time or another been attributed to Homo babilis can be assigned to the same morph. Thus, as discussed in the next section of this chapter, the paratype O H 13 fragmentary cranium and mandible seem actually to belong with the K N M - W T 15000/ER 1S13 morph, as does the newly described O H 65 palate also ascribed to H. habilis (Blumenschine et al., 2003). The O H 7 type mandible of Homo babilis is dentally primitive in many ways. Thus the slender incisors and canines, though worn, are nonetheless still tall-crowned. Its P i bears a minimally developed metaconid, which lies low on the lingual face of the protoconid. Its P2 protoconid and metaconid are tall, almost conical, and are distinctly separated all down their bases, with a thick paracristid in front and a yen' thick, low-lvine and shehiike and distally rounded postcingulid (as often seen among Miocene hominoids: Plate 1). T h e M l shows the classic "Y-5" cusp configuration, with a yen' large, centrally placed hypoconulid. There is a notch between this cusp and the hvpoconid, and a metastylid was present. The M 2 hypoconid does not cross the midline of the tooth as its counterpart does on M l , hence the long, probably narrow talonid basin runs directly down the middle of the crown to terminate at a hypoconulid region that is divided into a slightly larger buccal moiety and a

487

smaller lingual one. A metastylid is present. Given the configuration of this M2, it is plausible that OH 4, a paratype isolated M3, also belongs to this morph. All in all, these teeth arc much more primitive (for a hominoid) than any that we have described for australopiths, and certainly for any of the others that have been considered to belong to genus Homo. Further, as may be inferred from one of the cranial fragments attributed to O H 7, it appears that the foramen spinosum had been contained within the temporal bone. This is a primitive hominoid feature which, among the hominid cladc as currently accepted, is typically retained among the australopiths (Braga et al., 1998). All in all, then, there is little to point to if one wishes to defend the allocation of this specimen to a monophyletic genus Homo. We thus find ourselves forced to recommend, regretfully, that this specimen, and hence Homo babilis itself, be excluded from future considerations of the early evolution of our genus. O H 62 has also been allocated to Homo habilis. Only two worn and shattered teeth and various roots remain in this specimen. The central incisors would have been huge and the lateral ones tiny, hence this fossil displays extreme incisor heteromorphy. The canine roots are enormous, and the crowns would probably have been quite tall, although not yen' long m/d. As presen'ed on the unreconstructed L side, there appears to have been a low facial pillar that extended above the inferior nasal margin and probably continued up the side of the nasal aperture. The nasoalveolar clivus is relatively long and is gently fonvardly sloping, perhaps suggesting some upward flexion of this region. Taken together, these features are suggestive of affinity with the facial pillar-bearing australopith
488

H O M I N I D C R A N I O DENTAL M O K I M I O K O G I E S : A N

group, although the latter specimens to do not have the notch between the small hypocone and the protocone that is seen here. Cranially, the reconstructed calvaria O H 16 plausibly belongs to the same morph as O H 24, although it has rather unusual and medially placed supraorbital notches not present in the latter. The upper teeth attributed to O H 16 are rather worn, and show some signs of pathology. The upper incisors (lacking in O H 24) are very tall-crowned and show considerable hcteromorphy. The upper M l is reasonably similar to that of O H 24 in preserved morphology, but the premolars arc relatively smaller and less ovoid. The M2s are pathological; the M3s are extremely deeply and thickly wrinkled, but it does appear that the metacone region, hence the trigon basin, is distally truncated, and that the region of the postcingulum is quite large. The worn and broken assembled lower dentition of O H 16 includes narrow anterior teeth that had been quite high-crowned, and in this respect were quite O H 7-like.The P I apparently had a well-developed metaconid with a large and distinct mesial basin and a somewhat larger distal one, but it is unlikely to have worn down from an inital condition resembling O H 7. The P2 also had a large metaconid but only a tiny mesial basin, and its talonid was small; this would certainly not have worn down from an O H 7-like configuration. Like that of O H 7 the lower M l of O H 16 can be described as having a Y-pattern, but the centrally placed hypoconulid is much wider b/1 than that of O H 7, and the notch between it and the hypoconid is much narrower and much more buccally situated. The dental fragment in the position of the LM2 is quite worn, and thus conforms to the general state of wear of the other postcanine teeth; the RM2, in contrast, is much less worn, and is of a shape inconsistent with that of the M l . This tooth is also morphologically unlike the M 2 of O H 7, for instance, in being very broad b/1 mesially, with a distinct mesial taper. A cingulid on the protoconid and a small and lingually situated hypoconulid also differentiate this tooth from its homologuc in O H 7. T h e lower M3s of O H 16 arc also different from those of O H 7 in gross morphology, as well as in detail. That on the L would not have worn down to resemble O H 24, although it is possible that the R M 3 would have. O H 16 thus seems to be to some extent a composite, though as just suggested its most substantial components appear to be reasonably allocated to the same morph as O H 24.

OVERVIEW

Finall y, one of the Homo babilis paratvpes, the iso* lated upper R M l O H 6, is matched as alreadv noted by its counterpart in the maxilla L H 21a from Laetoli. Hill et al. (1992) described the isolated hominid temporal bone discovered at Chemcron in the Baringo Basin of northern Kenya as that of an "early Homo" primarily on the basis of characters of the articular and tympanic regions. However, other features of this specimen suggest an alternative interpretation. Such morphologies include the configuration of the nuchal ridge and the parietal notch, and the position of the foramen spinosum at the junction of the temporal and the sphenoid. Indeed the closest comparison to the Chemcron temporal is provided bv the penecontemporaneous "Black Skull," KNM-WT 17000 (Plate 25), most commonly attributed to Paranthropus aethiopicus (although, as noted, there is a problem with this name). Among other features, this latter specimen shares with Chemcron the placement of the foramen spinosum, a broad glenoid fossa with a smooth articular eminence, a horizontal depression in the area of the inferior semicircular canal, an upwardly tilted squamosal with a very narrow parietal notch and the absence of a mastoid notch at the rear of the temporal. In view of these similarities the appropriateness of regarding the Chemcron temporal as an early Homo fragment is far from evident (Plate 25). A plethora of fossils that have also been attributed to one or more early forms of Homo has come from the region immediately to the east of Lake Turkana in northern Kenya. Notable among these is the partial cranium K N M - E R 1470, made the type of the species Pithecanthropus (=Homo) rudolfensts by Alcxeev (1986), but moved to Australopithecus by Wood (1992), and more recently to Kenyanthropus by Leakey et al. (2001). ER 1470 consists of a fragmentary and reconstructed cranium that is missing all teeth and much of the basicranium, and in which the relationship of the face to neurocranium is not accurately ascertainable. In rear profile it matches well with the partial crania ER 407A, 1S05 and 1813, as well as with W T 15000. In neurocranial side view it matches with ER 407A, ER 1813, W T 15000 and O H 13. Because it is impossible to establish the angular relationship of the face with the neurocranium, and because of many uncertainties of reconstruction due to its highly fragmented condition, it is difficult to make any accurate comparisons of the front of the skull with specimens such as W T 15000 or ER 1813, which in turn makes it problematic to determine the

IIOMIMI) CRANIOHENTAL

MORPHOLOGIES:

affinities of the specimen. Given the very dose similarities in comparable pans between ER 1470 and 407A, it is tempting to extrapolate the basicranial characteristics of ER 1470 from the latter. Such features would include a well-developed mastoid process and a flartish nuchal plane behind the foramen magnum. These characters do not compare closelv with their counterparts in \ V T 15000 and ER 1813, although in the former case this might in part be due to the immaturity of the specimen (Plate 26). The orbital shape in ER 1470 is not at all reminiscent of that in \ V T 15000 and ER 1813; and though it is conceivable, if not likely, that ER 1470 belongs to a group that also embraces these specimens and those grouped with them elsewhere in this discussion, it seems best to leave this specimen in a "suspense account." Leakey et al. (2001) noted similarities between K N M - E R 1470 and the holotype of their new genus and species Kenyanthropus platyops from Lomekwi, K N M - W T 40000. We have not been able to see this latter specimen, but available illustrations show it has subcircular orbits (as also seen particularly in specimens from Drimolen, Hadar and perhaps Bouri) and a flat midfacial region with anteriorly facing zygomas (characteristic of australopiths in general). T h e two mandibles assigned by Leakey et al. to K, platyops (\VT 8556 and 16006) bear little mutual resemblance; thus the M l of \ V T 8556, although cracked, displays tall, prominent and distinct cusps that include a spiky and buccally placed hypoconulid, whereas the preserved M 3 of \ V T 16006 is much longer m/d, with relatively low cusps, a b/1 wide and m/d very long talonid basin that shows some wrinkling of the enamel, and a thick cingulid running fully around the protoconid. T h e preserved P2 and M l of W T 8556 are virtually identical to their counterparts KP 29287A and B from Kanapoi, while in the preserved morphology of its M 2 and M 3 W T 16006 is remarkably similar to other (and morphologically distinct) lower molars from Kanapoi, KP 29286D and I. W e have not been allowed to see this specimen, but one published drawing of the Australopithecus bahralghaz<*li from Chad shows premolars that look rather like those of W T 8556. Schrcnk et al. (1993) described a mandible (UR 501) from the Chiwondo Beds of Uraha, Malawi, as belonging to Homo rudolfensls. These authors made this allocation largely because of close resemblances they perceived between their fossil and the mandible KNM-ER 1802 that had been ascribed to this species

AN

OVERVIEW

489

by Wood (1992). However, the teeth in the Uraha specimen are weathered, broken and worn, and the only evident similarity of this specimen to ER 1802 lies in the relatively m/d long M 2 that preserves part of a very buccally placed hvpoconulid. Conversely, in the M l and M 2 of ER 1802 there is a very large metasrylid nestled between the bases of the metaconid and the small entoconid, whereas in Uraha the entoconid was quite large, at least on the M l , and there is no trace of mctastylids. Similarly, the P2 of 1802 has a broad, shclflike paracristid that is lacking altogether in Uraha. Given these observations, and the heavily worn teeth of UR 501, we regard this specimen as of uncertain affinities (Plate 27). Other "early Homo" specimens include the A L 666-1 palate described by Kimbel et al. (1996). This specimen possesses a very primitive and Australopithecuslike configuration of the nasoalveolar clivus relative to the palate. Specifically, the posterior pole of the clivus in A L 666-1 extends greatly over the the anterior part of the hard palate, with a steep drop from the former to the latter. This is a configuration that is not seen in Homo sapiens and other taxa, e.g., Homo erectus and Homo neanderthalensis, that more convincingly belong to its immediate clade. Further, as noted previously, dentally this specimen appears to be closely similar to the palate of Australopithecus garhl BOU-VP-12/130 from Bouri, also stratigraphically associated with very early stone tools. As in BOU-VP-12/130, and indeed in Hadar A L 200-la and similar specimens, in AL 666-1 the molars have distally truncated metacones, quite mesially shifted protocones and a postcingulum that originates above the level of the metacone and expands as it runs to the hypocone. Grounds for dissociating A L 666-1 from the Hadar Australopithecus sample thus seem fairly tenuous. Only a few South African fossils have been explicitly, if provisionally, referred to any member of the "cxAyHonuT group. Of these, only one was specifically referred to Homo habllls (Hughes and Tobias, 1977). This is the S t W 53 fossil, discussed earlier, which comes from an artifact-free infill within the A'ustratopithecus-bczrmg Member 4 of Sterkfontein (Kuman and Clarke, 2000), but which was long considered to be the maker of the stone tools found in Sterklontein Member 5, from which it was initially believed to be derived. Other South African fossils allocated at various times to "early Homo' are mostly fragmentary, and include the StW 80 mandibular piece from Sterkfontein (Kuman and Clarke, 2000), the S k 84/

490

H O M I N I D CRANIODENTAL M

partial cranium, and the l*Telanthropus,, mandible SK 15, discussed previously in connection with the SK 23/25 morph. Such specimens also include the isolated teeth from Swartkrans described by Grine (1993). We have discussed the South African hominid fossil assemblages in some detail in earlier paragraphs; and we reiterate here that while the affinities of all of these South African fossils would benefit from detailed reappraisal, none of them seems to fit naturally into a monophyletic and morphologically coherent genus Homo. Genera are monophyletic groupings of related species, and in any branching system there is a potentially limitless number of species that could be included in a group of this kind. At the same time, any monophyletic group should be reognizable on the basis of a suite of apomorphies. But precisely what those apomorphies are can only be determined by comparing the attributes of the species contained. Morphological definitions of supraspecific taxa, in other words, depend on the availability of phylogenies, which in turn depend on the adequate recognition of species. As this survey shows, the recognition of species within this extensive assemblage leaves much to be desired. Possession of an accurate or at least usable phylogeny is fundamental to the enterprise of reconstructing the biological past, and it is certainly the case that a morphological definition of our genus Homo will have to emerge from a reliable alpha taxonomy that is not yet in sight.

THE UBIQUITOUS HOMO ERECTUS: SPECIES OR GRAB-BAG? As the first truly ancient fossil hominid species to be described, Homo erectus has loomed large in paleoanthropology, as the standard-issue "hominid in the middle." To this species have been robotically assigned fossils from all over the Old World that date from almost every part of the Pleistocene; and as a result the notion of Homo erectus has become stretched beyond any morphological rationale. Oddly, this has meant that many paleoanthropologists who favor a gradualist model of human evolution now accept a species Homo erectus with an extraordinarily long life span, virtually coincident with the entire Pleistocene. But while it is undoubtedly convenient to have a receptacle of this kind into which any hominid from this period can

R P H O L O G I E S : Ax

OVERVIEW

effortlessly be thrown, it is nonetheless true that the ecumenical concept of Homo erectus covers a multitude of jarring morphologies, obscuring a great deal of complexity that invites investigation. In the following few sections of our discussion, we examine the lar^e assemblage of materials that have been assigned at one time or another to Homo erectus* and point out some of the morphological intricacies that it harbors. We start in the obvious place, with the type materials.

HOMO ERECTUS AND ITS PUTATIVE RELATIVES IN JAVA The Trinil holotype calotte of Homo erectus is highly autapomorphic in a variety of features. These include the extremely narrow, shelflike and laterally flaring supraorbital region that runs direcdy into a low, long frontal plane that appears keeled anteriorly by virtue of twin shallow depressions on either side of the midline; inwardly tilted cranial walls that are bordered above by faint and low temporal lines, and are shorter than the portion of the parietals above the lines that slopes in to the sagittal suture; and posterior distension of the rounded but acutely angled juncture of the occipital and nuchal planes along a wide, horizontal, somewhat torus-like structure. The superior nuchal line curves outward bilaterally, but is most emphasized toward the midline. With the exception of the Sangiran 17 specimen, the partial crania from the nearby Sangiran sites, including the crushed cranium S31, fit quite comfortably into the morph described by these features. Within this group, however, dicrc is noticeable variation in robustness, from the gracile crania such as Trinil 1 and Sangiran 2, to more heavily built and robusdy marked specimens such as Sangiran 41, 12, 10, and most notably Sangiran 4. In dicse latter specimens, nuchal scarring is more pronounced while the mastoid regions are more developed, and there is noticeable keeling along the sagittal suture (Plates 28,29). Internally, Sangiran 2, 4 and 26 reveal an additional apomorphy in their preserved petrosal regions: the sigmoid sinus divides along the back ox the petrosal so that at least one branch runs more or less horizontally along the petrosal body, and another descends behind it in the direction of the foramen magnum. A further unique feature is represented by Assuring of the medial petrosal wall, as in Sangiran 4. Sangiran 17 (SI7) is similar to Trinil 1 and other Sangiran crania in having an angular and somewhat distended occipital profile, together with a long*

MIXID C R A M O D E N T A L

M O R P I I O L O G t ES> 1 A N O V E R V I E W

sloping frontal plane that flows into the glabellar region. But rather than displaying the wide, short coronal protile of these latter fossils, $17 has much taller side walls, with a more rounded contour above. Additionally, it has a much lower juncture between the occipital and nuchal planes, with a concomitandv more horizontal orientation of the nuchal plane. Also in contrast to Trinil 1 and S2, in which the relatively straight supraorbital torus flows into the frontal laterally along its entire length, in S17 the tori are more arced over each orbit and there is a posttoral sulcus that becomes increasingly distinct laterally. The zv^omas of S17 also differ from those of SlO, the only other example ot this clement from the Sangiran basin, in flaring interiorly even more markedly. However, S i 7 does possess, bilaterally, the arborizing sinus pattern of S2, S4 and S26. In S i 7 the palate is relatively parallel-sided, whereas the cheek-tooth rows of the S4 palate diverge posteriorly. In S17 the circular, moderately large incisive foramen lies quite close to the alveolar margin, and the incisive canal leading to it internally appears to be rather vertical. In contrast, in S4 the incisive foramen emerges farther back in the palate, level with the distal side of P i , with a fan-shaped depression opening anteriorly into two diverging canals. The preserved R C , L P 1 , and L M 1 - M 3 of S17 are quite small. T h e canine is narrow, with a lingual excavation, and is obliquely oriented in the jaw; the P i is also narrow m/d, with a deep fissure between the probably tall paracone and metacone, and a welldeveloped parastyle. T h e P i appears small relative to M l , especially m/d. T h e molars decrease markedly in size from M l to M 3 , with a noticeable diminution of the metacone that is smaller than the paracone on M l and is virtually absent by M 3 . All molars are thus narrower m/d along their buccal than along their lingual sides. In the S4 palate the dentition is larger than in Si7. T h e taller canine lies in line with the postcanine teeth and, though worn, remains large relative to the postcanines, as does the more rounded and chunk}' Pi, whose paracone and metacone are separated by a shallower and wrinkled groove. T h e molars of S4 are much longer m/d than those of S17 compared to their widths; M 2 is the largest of the molars in all dimensions, and M 3 is not significantly smaller than M l . In addition, the metacone remains relatively large in all molars. Specimens showing marked dental similarity to S4 include the crushed skull S27, the m i l i a r y fragment S7-35 and the two associated teeth b / o / ,

491

plus molars S7-3b and c, S7-53 and S7-10. Amon* the isolated teeth from Sangiran, three are similar to one another and are different from both the S4 and S l 7 molar morphs. These are S71, a maxillarv fragment with one tooth, and the isolated upper molars S7-3d and 7-73. These all share great b/1 width, as well as distal rounding from the paracone around to the protocone without distinct delineation of the cusps, especially the distal ones (Plate 30). In the lower dentitions from Sangiran there appear to be morph differences as well. The Sib mandible, containing rather worn R P 2 - M 3 , is clearlv distinct trom other Sangiran mandibles, though it is matched closely by the isolated lower molars S20, 42, 43, 62, 64 and 65, by the isolated P2 S7-69 and presumptively by the isolated P i S7-25, which is slirfulv distended lingually rather than markedly distolingually as in S6 (see below). It has a moderately sized metaconid that is somewhat mesiaUy placed and on either side ot which is a very deep but narrow fovea. In contrast, S6 lacks a metaconid and has a large ralonid basin. Sib has a tall but relatively m/1 thin corpus, and is narrower across the front. In general, the preserved teeth are smaller and narrower b/1. The P2 of S i b is small relative to M l both m/d and HI, lacks buccal swelling of the crown and has a short talonid. The molars are long and narrow, but rounded and ovoid. The unworn isolated teeth in this morph have wrinkling especially on the internal faces of the cusps, and a broad paraconid shelf lying between the protoconid and metaconid (rather than in front). The metaconid is longer m/d than the protoconid; the entoconid is smaller and lies distal to the hvpoconid. T h e cusps are well delineated by grooves, and the hvpoconulid may be twinned and is buecally placed. Other partial mandibles that may belong in this morph include S33 and SbS013. The mandible S22 also corresponds with Sib in a variety of respects, and could conceivably be a robust representative ot the same kind of hominid despite its more elongate molars and other differences. The mandibular fragment SS ("Mci*anfbropus Bl preserves a worn M 3 in which the metaconid is subequal to the protoconid. Although the metaconid is not significantly larger than the protoconid, the hvpoconid and entoconid are small, there is a vestige of a shelf between these two cusps, and the hvpoconulid is quite buecally r ^ e d In contrast to the specimens just discussed, M>. the holotvpe of Mcgantbrvpus ^ f ^ ™ .a relatively larger ?2 relative to M l both m/d and b/1, i>

-\<)2

HOMINII)

CKANIOUKNTAI,

\\<>H\'\toi,<>(i\KH:

more huccally swollen, ami lias a longer talonid. The 1\2 is also narrowest mesially and is greatly distended distolingually, in contrast to the more roundcdly rectangular outline of this tooth in Sib. The preserved M1 of S6 is worn, but it was deeply crenulated and has a distinct, thick cingulid around the protoconid. I he mctaconid lies opposite the protoconid, with which it is subequal in size, and the relatively large cntoconid lies opposite the hypoconid. The hypoconulid is single ami separated from the cntoconid by a notch. Distinct notches also separate the protoconid from the hypoconid, and the hypoconid from the cntoconid. The mandibular fragment S5 (holotype of Pithecanthropus dubius) can be associated with S6 by the massiveness of its jaw; and though the preserved Ml in this specimen is heavily worn as well as broken, it apparently bad originally been quite crenulated. In addition, a cingulid was present around the protoconid of its M2, and the metaconid, which lies opposite the protoconid, is also subequal in size with it. It is also possible that the mandibular fragments S5 and S70 belong in this group. S5 has an M2 that is larger than the M l , and S70 has a M 3 that is larger than M2. If this association is correct, this morph was characterized by a posterior molar size increase (Plate 31). The partial mandible S9 is very distinctive. Unlike any of the specimens just mentioned, it has a long and sloping postincisal plane, is very narrow across the front, and the cheek tooth rows would have been relatively straight and quite divergent from behind the small canine. Also, the isolated and large R lower molar S7-76 is unlike any of the teeth just described, having a high crown and extremely vertical sides. These two specimens appear to be outliers in the total Sangiran sample, and cannot currently be assigned to any broader morphs. The differences in both cranial and upper dental morphology between S17 and the other Sangiran hominids we have just discussed are substantial. It is possible, of course, that SI7 is wildly atypical of its group, but the probability of this is reduced by the fact that a few other albeit much less complete specimens, such as the isolated upper molar S7-6 and the basicranial fragment S14, arc similar to it. Matching different cranial and dental elements with each other in the absence of complete crania is an uncertain process, but it seems reasonable to associate the calotte S2 with the palate and dentition S4. It would be more speculative, however, to attempt to match either of the two principal

AN

OVKRVIFV

lower dental morphs, as exemplified by Sib and S6, respectively, with cither of the two upper craniodcntal morphs (as exemplified by S2/4 and S17), and we do not presume to do so here. Whatever the case, there docs not appear to be a smooth spectrum of morphological diversity in the cranium and upper dentition among these Sangiran hominids; taken together with the magnitude of the differences we have noted, this might favor the notion that here we are sampling two different morphs, both descended from an ancestor with an arborizing sigmoid sinus. At what systematic level this morphic difference would be significant is not currently clear to us. Should it be considered appropriate to separate them into different species, the Trinil/Sangiran 2 group would obviously take the name Homo erectus, while no name is yet available for the Sangiran 17

morph. Three crania arc now known from the Sambungmacan/Poloyo region on the Solo River to the north and cast of Sangiran, although one of them (SM4) was found too late to be described in this volume. The two calvariac published as of this writing, Sambungmacan (SM) 1 and 3, are generally similar in size and structure. They share a brow morphology in which the relatively horizontal tori thicken laterally, and in SM3 it is possible to determine that the tori were continuous across glabella. Continuous suprameatal/supramastoid crests are well developed, and the nuchal plane in each undercuts the occiput to produce a torus that is well defined below as well as less aggressively above. As seen from behind, the superior nuchal line becomes more marked as it curves outward and down on both sides. The side walls of the braincase are relatively tall, and the coronal profile is roundcdly tent-shaped. The articular fossae are deep and constricted a/p. There are bilateral shallow depressions on either side of the midline just behind the bregma. Together these features define a homogeneous morph that differs from both the Trinil/Sangiran 2 and Sangiran 17 groups, and remains more primitive than either in lacking arborization of the sigmoid sinus. It is also more primitive than the Trinil/Sangiran 2 morph in its coronal profile, lacking the squat rounded contour of the latter. The Ngawi 1 calvaria, found a short way to the south, is similar to the Sambungmacan specimens, most notably SMI, differing from them primarily in having s/i taller supraorbital tori. We have no difficulty in assigning both Sambungmacan specimens and Ngawi to the same morph (sec Plates 28 and 29).

IIoMIMD

CHANIODKNTAL

M O K I'll O LO(i I EJ* I A s

The Ngandong cranial scries is similarly quite homogeneous, but it is also distinctive in certain details. These crania arc distinguished from the Trinil/Sangiran material in all the ways in which the Ngawi and Sambungmacan specimens are, but in addition they present relatively capacious braincascs with more or less vertical side walls bearing raised temporal lines that give a puffy appearance to the bone around them. They are large, and more robustly built than the Sambungmacan/Ngawi hominids, with a greater tendency to rearwards projection of an occipital torus that is well defined above as well as below. Nonetheless, taken together the Ngandong, Sambungmacan and Ngawi (N/S/N) hominids appear to form a relatively cohesive morph that is distinguished by the very derived morphology of the horizontal, barlikc and laterally thickening supraorbital tori, which arc continuous across glabella (sec Plates 28 and 29). Indeed, claims to the contrary notwithstanding, these hominids arc among the few primates that have anything approaching a barlikc supraorbital torus (cf. Schwartz, 1998). Thcv arc also united by their nuchal morphology, with superior nuchal lines that become more emphasized as they curve laterally and down, as well as by features cited earlier for Sambungmacan. Should it be considered desirable to consider the N/S/N morph its own species, the earliest available name would be Homo so/oensis Oppcnoorth, 1932.

PUTATIVE HOMO ERECTUS FROM CHINA The large scries of fragmentary crania recovered from Locality 1 (the "Lower Cave") at Zhoukoudian, China, has usually been considered a classic example of eastern Asian Homo erectus. But the realization that the entire assemblage of fossils from Java conventionally assigned to this species is not morphologically homogeneous, and may not even be systematically uniform, provokes the question of whether the Zhoukoudian materials belong to the same exact taxon as that represented by the Homo erectus type material from Trinil. And the answer to this question may be no. The Zhoukoudian Lower Cave scries is distinctive in certain respects. All crania display a vertical component to the supraorbital torus, so that in midsagittal profile they show a complete posttoral sulcus, a feature not seen in the Indonesian crania. Even in Sangiran 17, where there is a small excavation laterally, there is no continuous posttoral sulcus from side

OVEKVIKW

493

to side that dramatically defines the supraorbital torus right across the junction between face and braincase. Additionally, glabella lies somewhat below the superior surfaces of the tori, so that in frontal view there is a marked central dip in the toral profile. On the other hand, these crania are swollen in the area of bregma and bear bilateral depressions behind this point, as in the N/S/N group. Other similarities of this kind are also present. For example, the central region of the superior nuchal line is distended posteriorly, and its superior surface is marked by a shallow horizontal depression. And the Zhoukoudian crania possess very deep articular fossae and pronounced and continuous supramcatal/supramastoid crests, also as in the N/S/N group. These resemblances may suggest that the affinities of the Zhoukoudian hominid lie with this Javanese morph rather than with the Trinil/Sangiran morph that defines Homo erectus. It is notable that the three preserved Zhoukoudian Lower Cave upper dentitions do not match any of their counterparts from Sangiran. Thus the molars of Sangiran 4 emphasize m/d length while those from Zhoukoudian emphasize b/1 width. The M3 of Sangiran 4 is small relative to M 2 , while in the Zhoukoudian specimens it is quite large. In Sangiran 17 the molars become increasingly truncated in the metacone region and decrease in size from front to back, whereas in the Zhoukoudian specimens the metacone stays large on all three fossils, and the molars do not diminish significantly in size posteriorly (Plate 32). If the N/S/N and Zhoukoudian fossils are most appropriately viewed as infraspecific variants of a species that excludes the Trinil/Sangiran 2 morph, then Homo pckinensis (Black, 1927) would appear to be the appropriate name for the species to which they belong. If it is preferred to separate the Zhoukoudian from the N/S/N fossils at the species level, then Homo pckinensis remains with the Zhoukoudian materials, and the N/S/N group becomes Homo soloensis. Only if it is considered most apposite (as it will be by many) to include the N/S/N, Zhoukoudian and Trinil/ Sangiran 2 hominids in a single and morphologically extremely diverse species, would Homo erectus be the appropriate name for all members of this group. Various other Chinese fossils have also been considered to represent Homo erectus. These include the fossils from Longgupo, Lantian (Gongwangling, Chcnjiawo), Yunxian, Hcxian and Nanjing. The putativcly early incisor from Longgupo does appear to be hominid, although in our view it is of indeterminate

** '*

HoMINII)

CllANIODBNTAI*

M c ui'iioLodiii.s: A N OVISRVIBW

species affinities; and the jaw fragment from the same site might better be characterized as "hominoid" (Schwartz and Tattcrsall, 1996b) than ascribed to any particular hominid species. The Lantian specimens consist of a badly crushed and highly incomplete cranium (Chcnjiawo) and a mandibular body containing a broken LM1 (Gongwangling). The Gongwangling mandible is distinguished by an RM1 alveolus displaying two distinct mesial roots and one large distal one, plus M2 alveoli showing three roots, a shallow one mesiobuccally, and deeper ones mcsiolingually and distolingually that are separated by a distinct septum. These arc unusual conformations—not overlapping with the C-shapcd M2 root sometimes described for northern Asian Homo sapiens (Turner, 19S4). Interestingly, the M l alveoli of the Zhoukoudian partial mandible T 169/20 HI.12 arc identical in form. However, the M2 alveolar region in the Zhoukoudian specimen has a single deep and m/d long buccal alveolus and two shallow lingual alveoli. The crushed Chenjiawo cranium is not highly informative, but seems on the contrary to resemble the Yunxian material in the intcrorbital region and the area lateral to it. The Yunxian site has produced two large crania, both badly crushed, but particularly in the better-preserved specimen EV 9002 it is possible to see a superiorly broad but inferiorly tapering intcrorbital region. The glabellar region and the supraorbital region lateral to it show an "edge" delineating the upper margin of the supraorbital torus. To some extent both of these conditions may also characterize die Chcnjiawo skull. But in supraorbital features the Yunxian crania most closely recall those from Dali and Jinniushan that have been compared to Homo hexdelbergensis, and they lack the continuous posttoral sulcus typical of the Zhoukoudian crania. It thus seems premature to exercise any systematic judgment on the position of the Lantian material, and even on whether both specimens represent the same species. We have unfortunately only been able to see casts of the Hexian and Nanjing hominid crania. The latter appear to resemble those from Zhoukoudian, but the large Hexian calvaria is more difficult to interpret. Compared to Zhoukoudian its supraorbital tori, though tall, do not thicken laterally, and the suprameatal/supramastoid crests are not as well developed. Viewed from the rear, this specimen displays a coronal profile that recalls the Trinil 1/Sangiran 2 morph, combining great width with short but vertical side walls and a broad, flatfish top. In contrast to

fossils of the Trinil morph, however, the occipital torus in Hexian is well marked below and probably above, and extends more completely across between the mastoid regions. Also, the occiput itself is not distended posteriorly in a blunt angle as is typical of the Trinil morph, the occipital plane is shorter, the supraorbital tori are more arced over the orbits, and the frontal rises up from the posttoral plane rather than flowing smoothly back from it. In many ways this cranium more closely resembles the smaller and rather inscrutable cranium from Sale in Morocco.

PUTATIVE HOMO ERECTUS FROM AFRICA Many fossil hominid cranial specimens from eastern Africa have been referred at one time or another to Homo erectus. Alternatively attributed by many to Homo ergastcr (a species based on a mandible: KNMER 992), these fossils include the skull (and postcranium) KNM-WT 15000, the cranium KNM-ER 3733, the calvaria ER 3883, the partial cranium ER 3732 and a variety of more fragmentary specimens. The O H 9 partial calvaria from Olduvai Gorge Bed II has also traditionally been assigned to Homo erectus^ and additionally of interest here are the cranium KNM-ER 1813 and the Olduvai specimen OH13, both of which have been assigned to Homo habilis (Leakey, Tobias and Napier, 1964; Howell, 1978). The African fossil most commonly taken as the classic exemplar of adult Homo ergaster (or "African Homo erectus") is the EastTurkana cranium KNM-ER 3733. In this splendid specimen the brows arc independently over each orbit, and project both forward and up, forming a distinct posttoral sulcus in front of a steep frontal rise that peaks quite far forward; posteriorly the skull is relatively tall compared to its width, and the sidewalls of the vault are curved. The temporal lines are raised and arise far medially, behind the midpoint of the orbit. In all of these features this cranium differs very distincdy from the type material of Indonesian Homo erectus. But such morphological disjunction does not stop here. It might be unsurprising that the West Turkana skull KNM-WT 15000 is morphologically different from Trinil/Sangiran 2 Homo erectus^ as well as from the distinctive Sangiran 17. More surprising, perhaps, is that this Kenyan specimen is equally different from ER 3733. W T 15000 is admittedly adolescent, while ER 3733 is adult. But subsequent growth would not have made it any more similar to ER 3733; if anything, the differences

HttKT*l3> C * A 3 : f O a i » - i j t t

Moa:riEOIL008!E*: A ^

2Xrzx3r dJeaay rr^*sar w-ir&f hss^ fcees ccacr ir ai^nrx*'' a £ t r r J C preferred ccs sc dffss*»2££ ct dszxt aaact r~*-''Ti mc>s i c lucecc*" critcii! CUEE c as ER 5735. na ZCZnCXZXXi a'ja. l o t at* or cat r » o ic*ec «ea* are iik*> essatacr V* it 15LOJ Las .a iccirea aarasnuer ^ T » I c i gmrfr. smort a?3<se£*r p^pizzzsczz cat aasa! at«erc=rr cs i:cir maafc c»^a=i cc W T 1S1C0 i r e grrrrr coocrj'e ^

OY££TC!£Wr

495

\ V T 1 5 X 0 caear is z r^-fc jtx! caeaii3r xraaa: r r t iaas i nesiotaairailjr
Espreccat, .zad 2 faericy -«vyr-.*~»r>-f^ cosrpnoccoaceGieaax caca ct" cat Irvayefare *r*3 cat rwo Acacia

A 3 c a , cc" coarse, raises another coesaba. \Vaae Sanpran 4 cad i s S s cleacy aaasr b t regarded as Hzmo rrs^ui^ k ccaer cc cat African sbraas fast &CUSSe^i HzTTft grgSS^T* T h e I T ^ t S p t C a n e a Off / & T O

ai2iz! aperaurr. l a aura, Jxch cat E R 5753 ^-^j W T Hans: is, i o w t i c ; aaore o r less n-.*-*^-?! Q coaxxarablt r-ir^ S H 2 ' i r s a r r s oc» cat EH 5752 parcal prs3 cat cristeact o f a coosistt J»' b c a cc caest £osfi£k l a coctrasr both zo cat f->doaesiaa r r p t caateriak o f Hvmo erertta and to E R JWJO. ; -v ERv > M >1/J / J 2 caarra iJacnK'* idb 1 rscas cazi procnadt forwiad 2ad tiT'grrh- dcwa, oiTtrhfrygr^g 112*000 s a d cat » s r o f cat tacs^ cat Qisfc] bocats ^rt ^Jar C2asnTcriitih* -gyy3 dt&ctad ikaosr TirtaciZh* c*od ciiaoca, prdbitb}r 3ariiiag pos4rtr4fid Btilt oprTt?1 o^ra'^rd canTEtsre; and cat aVccczS ^DC«S sTTOZi^Y vp and bark, itica cat ia^atsr pake
«yzsar 2* cat aaandrfe KNM-ER 992, which bears ©rily low^er ceeca. And cat OCJT cdatx ezsz Acacsa s^ccaasa or ca$ CTra? cast possssscs cccapcsaut r«ca is V*T ISDCiiX nx Trcaca 2a ziaaosr oazapltct k?nrr jzw 25 p ^ s s r s s i l a ER 992 cat JCSTST C2aaat5 ^re verr t£*I sad baaoaEarsxTr -oocaprssssd; cat pnxococad is cat Izrsesr case* o f cat ^stcaar rcyaatalzr; waica btsrs imryjifl sad & c d ior cat Tuxzsnxx: io3ar and cat cacil£i$ d i d ; ih* had not h a j ,w,eI3-eix2T,2ttd 8aRgr?
**^

IIOMINII) GHANIODENTAI,

M O HOMOLOGIES: AN

united by various aspects of cranial morphology, including their short, high, cranial vaults (rather like that of O H 13); brows that arc rounded in profile, relatively tall, and arc over each orbit; frontals that rise from behind a very short posttoral plane, nasal apertures that arc tall and relatively narrow for the size of the face, tapering superiorly; and nasoalvcolar clivuscs that arc long and forwardly sloping. ER 1813 also compares closely to W T 15000 in its preserved upper dentition, as well as to the palate O H 13. For example, all three have an almost flat-surfaced but highcrowned M l , with the hypoconc at the same level as the protoconc, and delineated from it by a small notch lingually, just distal to the midline of the crown. Thus the hypoconc is long m/d, with a mesial rather than a distal emphasis. In all three M2 is similar in many ways to M l , but has a more reduced mctaconc and less of a lingual distinction between the mctaconc and protoconc. Both M l and M2 have very thick postcingula that terminate just on the lingual side of the mctaconc. At least in W T 15000 and ER 1813, the P2s arc similar in having a pronounced, bulbous, centrally placed paracone, and a continuous crista that runs mcsially away from the paracone, swings right around the periphery of the tooth and terminates on its distal side in a small swelling. The preserved M3s of O H 13 and ER 1813 show similar kinds of deep crenulation, with a reduced mctaconc and a broad, shclflike postcingulum that terminates in a small, spikelike hypocone (rather as in O H 24, which may possibly imply the existence here of a larger cladc of uncertain composition). Even though the RI2 of ER 1813 is worn, it is similar to that of W T 15000 in being a small tooth whose sides flare out dramatically from the neck. W T 15000, ER 1813 and O H 1 3 are thus united in a distinctive upper dental morph. Notwithstanding its worn teeth, the O H 65 palate recently described by Blumcnschine ct al. (2003) appears to fit a similar description, e.g., in both upper molars the hypocone is distended mcsially, but only on M l is it separated lingually from the protoconc by a notch; and on M 3 there appears to have been a very thick cingulum terminating in a very tiny hypocone. The lower teeth of W T 15000 compare well to those attributed to O H 13 (one of the para types of Homo hubil'ts). In both individuals the premolars taper mcsially, with an oblique lingual surface; the small mctaconid lies opposite the protoconid, and there is a moderately small fovea in front and a larger one behind. T h e P2s have a larger mctaconid that lies slightly

OVBKVIBW

mesial to the protoconid, and a very wide shclflike cristid runs from the protoconid to the base of the mctaconid. A smaller cristid lies mcsially. The molars of O H 13 arc much more worn than in W T 15000, However, similarities arc seen on M l in the oblique groove, lying between the hypoconulid and hypoconid that runs mcsiolingually to the base of the mctaconid. Thus the base of the hypoconid terminates at the base of the mctaconid and cuts across the base of the cntoconid, truncating it. The M l of W T 15000 is deeply crcnulatcd, with a distinct protostylid and a scries of mctastylids. On this tooth in O H 13 vestiges of grooves remain in the position of the protostylid, and there is at least one mctastylid. In W T 15000 a groove between the protoconid and mctaconid lies very far behind the mesial edge of the tooth; there is a vestige of such a structure in O H 13. In both fossils the hypoconulid is large and wedge-shaped, and straddles the midline of the crown. In M2 of both W T 15000 and O H 13 the cntoconid is greatly truncated, and a groove between the protoconid and mctaconid lies far back from the mesial edge. Also in both, the hypoconulid is buccally placed. In W T 15000 there is a distinct wedge-shaped ledge in the distolingual surface of the crown, while in O H 13 there is a hint of a similar feature. The M i s of both fossils taper slightly distally, whereas the M2s are more broadly rounded. There appears, then, to exist a reasonably homogenous dental morph that embraces fossils from Olduvai, Koobi Fora and West Turkana, and that is best represented by the skeleton W T 15000. The O H 9 partial calvaria from Tanzania is usually vaguely referred to by the phrase, "African Homo ercctus? but in reality it continues to pose a puzzle. For morphologically this specimen sits very uneasily not only with the Trinil/Sangiran materials, but with all of the Kenyan fossils just discussed. Neither docs it make a match for the newly described Daka "Homo erectiu cranium from Ethiopia (Asfaw et al, 2002), despite having in common with it substantial dissimilarity, from Trinil. Photographs of Daka (a fossil we have not seen) show a rather tall and vertical-sided coronal profile that is at variance with the almost triangular coronal profile of O H 9. T h e s/i tall supraorbital tori of O H 9 arc essentially horizontal across the top of the face, and arc confluent with an equally tall and pronounced glabellar region that lies only slightly below them. In the Daka specimen, although the supraorbital tori arc also very tall s/i, they arc dramatically above each orbit, continuing far inferiorly at their medial

HOM.X.O CRAN.OUENTAL

MORPMOLOO.ES:

extremities, and arc separated medially by a wcll-dcprcsscd glabellar region. When viewed from below postorbital constriction in O H 9 is much greater than in Daka, and when seen from the front the exposed neurocranium of O H 9 is much narrower and lower as it rises above the tori. Daka remains primitive relative to O H 9 in that its foramen ovale lies medially in line with the articular fossa, rather than anterior to it, and there is a further distinction in that the carotid foramen in O H 9 is small but enclosed in a voluminous vestibule together with the large jugular foramen, whereas in Daka the large carotid foramen opens independently. T h e nuchal plane is markedly longer in Daka than in O H 9, reflecting a much more anteriorly placed mastoid region in the former. This conformation is also reflected in the substantially longer temporal fossa of O H 9. Additionally, the posterior root of the zygomatic arch of Daka turns forward much more rapidly than in O H 9, suggesting that the temporal fossa in Daka was also a great deal narrower. Finally, we might remark that the temporal line in Daka appears to fade out far anteriorly on the parietals, whereas in O H 9 it continues down on to the mastoid process as the border of a puffed-out lateral cranial wall. There seems to be litde justification here for Asfaw et al. s (2002) allocation of the Daka specimen to Homo erectus, and even less for their claim of its "morphological intermediacy between earlier and later African [Homo erectus] specimens" (2002: 319). Other Ethiopian specimens that have been assigned to Homo erectus include the fragmentary fossils from the various sites at Melka Konture. The very thick-boned Gombore II frontal fragment lacks any indication of a posttoral sulcus laterally, and the frontal shows a long, gently rising slope from the supraorbital region. A low and thick temporal line runs back from behind the zygomatic process, and there is marked postorbital constriction. There may have been some low frontal doming medially, and the orbital margin was probably strongly flared laterally. In comparable features this specimen is not a t *l* sl™~ ilar to the penecontemporaneous Daka and and O H * crania, or to any of the other putative Homo erectus material discussed earlier. Other Melka konture cranial fragments are u n h e a l i n g . T h e dm2 of the Garba subadult mandible M K 8 1 G A R IV is a somewhat elongated tooth, rather straight across the mesial sic* and rounded distally. It has a thick P ^ ™ f * £ and a distinct buccal cingulid.The metaconid i rath longer m/d than the protoconid, hence the entoconid

AN OVERVIEW

497

hes slightly distal to the slightly larger hypoconid. A b/1-oriented groove that originates internal to the buccal side of the tooth and terminates in the talonid basin partially subdivides the protoconid into a larger mesial and smaller distal moiety. There arc deep grooves between all main cusps, and especially between the hypoconid and hypoconulid. The buccally placed hypoconulid is distinctive in being compressed m/d; and distal to it and to the hypoconid is a b/i wide, deep, but not m/d long and slightly lingually oriented basin, whose edges arc very clearly delineated. Although the crown is somewhat worn, there are still deep crenulations in its surface. Close matches to this distinctive morphology are found in the relatively unworn R lower dm2s OH 30 and O H 63, the L lower dm2s from Allia Bay (the quite unworn ER 20422 and the worn and weathered ER 30201), and the unworn L and R lower dm2s from Kanapoi (KP 31712K and J, respectively, although the former differs somewhat in the subdivision of the protoconid). Also closely similar are some of the isolated teeth from the Shungura Fm in the Omo Basin of southern Ethiopia. These include the lower left dm2s L628-9, K7-69-19, 121-73-1950, all more or less unworn, the Omo 227 fragment of mandible with L d m l - d m 2 , and probably also the somewhat worn L629-10. In addition, the very worn dm2s in the mandible KNM-ER 820 could very well have originally looked like the Garba dm2, not just because of their outline, but because they preserve a deep notch between the hypoconid and the buccally quite compressed hypoconulid. They also preserve remnants of a paraconid shelf and a distolingually oriented basin. The unerupted M l of the Garba mandible has deep enamel crenulation, and a relatively m/d long and wedge-shaped paraconid shelf that intrudes between the protoconid and metaconid. A groove subdivides the base of the protoconid internally, a series of cuspulids rings the internal base of the slightly m/d longer metaconid, and there is a large vedge shaped h>Toconulid that, while being centrally placed, has its apex close to the h>Tocomd There cusp rate cal cingul somewhat worn M i s in KNM-ER 820.

By its « ^ ^ * ^ t t T i i h ;« Omo specimen 227 presents in Omo spec

nt

information

498

I I o M l N I l ) CltANlODKNTAL M t) KI'!! O LOO I KSI A.N

on the d m l in this morph. It is smaller both b/1 and m/d than the dm2, tapers slightly mesially, and is more acutely rounded mesially than distally. The trigonid is larger and taller than the talonid, and the metaconid lies somewhat distially to the subequal protocoled. A very thick paracristid runs mesially and slightly lingually down the face of the protoconid; at its base it turns sharply and arcs back to the base of the metaconid, enclosing a large, deep and mesiolingually facing trigonid basin. The buccal side of the protoconid is rather bulbous; the lingual side of the metaconid is flatter. The steep distal side of these cusps faces slightly obliquely onto the lower talonid, which is short m/d and rounded distally. The hypoconid is much larger than the entoconid, and the two cusps arc connected distally by a thick crest. Chavaillon and Coppens (1975) allocated the Garba jaw to Homo erectus, an attribution also adopted by Wood (1991) for the KNM-ER 820 mandible. O n the other hand, Tobias (1991) allocated the O H 30 isolated lower dm2 to Australopithecus boisei> while Day (1985) regarded it as indeterminate. In Volume 2 of this series, we included O H 63 in the O H 7 morph, but based on the comparisons above we would now remove it from that group and associate it instead with the Garba morph. The apparent lower Olduvai/ East Turkana affinities of the Ethiopian specimen raises the question of whether the Garba IV locality might not be somewhat older than current estimates. In any event, given the distinctiveness of its teeth it is evident that Homo erectus is an inappropriate allocation for the Garba jaw, the systematic position of which demands reappraisal. It is tantalizing that, while we have a clear indication of morphological diversity in the east African record, the lack of definitive association between some ot the cranial and mandibular elements in this assemblage still leaves us with an incomplete picture. Nonetheless, it is evident that all of the morphologies enumerated in the preceding paragraphs will need to be addressed in future studies, and their distributions clarified; and it will be hard to do this if all of these specimens are brushed, together with the entire spectrum of Indonesian hominids, under the allencompassing rug of erectuslergaster. Clearly, several distinctive morphs are at issue here, and eventually the matter of potential taxic diversity will have to be broached. If it is decided that any of the morphs we have pointed to deserves species-level recognition, Homo ergaster Groves and Mazak, 1975, is the appropriate

OVLRVIKW

name for the species that includes the mandible KNM-ER 992. Homo microcranous Ferguson, 1995, is available for the W T 15000/ER 1813/OH 13 morph. Homo leakeyi Hebcrer, 1963, is available for O H 9; and no names arc currently available for the species to which the very different (both from the foregoing and from each other) ER 3733 and 3883/3732 belong, or, indeed, for the Garba morph. As for Daka, should future investigations confirm a morphological and systematic association between it and the Ccprano calvaria from Italy (sec below), the available name is Homo cepranensis Mallcgni ct al., 2003.

PUTATIVE HOMO ERKCTUS FROM EUROPE The site of Dmanisi in the Republic of Georgia has recently produced a trove of horn in id fossils whose allocation to Homo erectus (Gabunia and Vekua, 1995) as well as to Homo ergaster (Gabunia ct al., 2000) has been suggested (see Plates 33-35). These Dmanisi materials together make an extremely interesting assemblage, not least for its heterogeneity, which has been yet further enlarged by more recent discoveries, for it is hard to match the initial lower jaw with cither of the first-described Dmanisi crania on the grounds of size or shape, while the three crania described as of this writing show substantial mutual differences. Further, the initial lower jaw is clearly not Homo ergaster as represented by the type specimen KNM-ER 992, and neither docs it fit with Homo erectus material from Java (Schwartz, 2000, 2004b). As first pointed out by their describers, the two crania published in 2000 show substantial morphological differences from each other in the supraorbital, mastoid and nuchal regions, as well as in their various profiles (Gabunia et al., 2000a, b). The degree of such distinctions may suggest taxic difference (Schwartz, 2000, 2004b). The same is true of the recently published third skull (Vekua et al., 2002), and of the second mandible recendy made the holotype of Homo georgicus (Gabunia et al., 2002), when compared to the jaw originally published by Gabunia and Vekua (1995). The cranium D2282 shows a distinctly Trinil/Sangiran 2-like coronal profile of the neurocranium, unlike its companion D2280, which is much taller and is rounded rather than flat across> the top. In side view, the neurocranium of D22S2 has a very low and long profile, which also contrasts with the higher and more rounded profile of D2280. In D2282 the supraorbital tori are s/i thin, and behind them lies a

HOMINID CRANIODENTAL MORPHOLOGIES: AX

fairly long posttoral plane from behind which the low frontal rises. This low frontal plane is continuous across glabella. In D2280 the frontal rises directly from the s/i taller supraorbital tori, whose superior surfaces arc over each orbit, and the superior margins of the orbits curve down medially toward the frontonasal suture. The nuchal region of D2280 bears a distinct, downward-pointed external occipital protuberance, on either side of which is a well-defined superior nuchal line. The nuchal region of D2282 is essentially featureless. The preserved L side of D2280 shows a Sangiran 2-like bifurcation of the sigmoid sinus, whereas this sinus remains single in D2282. D22S2 retains only its R P 2 - M 1 and L M 1 - M 2 , but these teeth seem to compare most closely with those in the Sangiran 4 palate, especially in that the preserved P2 is rounded and large relative to M l , and in all molars the the distal side is arcuate and the very thick postprotocrista rises noticeably above the level of the hypocone. We can detect no significant similarities between the upper dentition of D2282 and that of either K N M - W T 15000 or the preserved M 2 of KNM-ER 3733. In both the Dmanisi D2282 and Sangiran palates, there is a sunken groove running forward from the incisive foramen. We have not yet seen the third cranium D2700, but judging from illustrations it is different in aspect from either of those just described. In lateral profile this specimen is unusual among hominoids in having a straight plane running from the nasals to glabella, from which the frontal slopes back directly. In coronal profile the cranium is continuously rounded, and almost triangular. From the front not only are the orbits almost circular, but there is virtually no delineation of any supraorbital tori, and the lateral margins of the orbits flare outward toward the zygomas. T h e infraorbital region is flat, vertical and forward-facing, and the infraorbital foramina lie markedly below the infraorbital margin—as probably did the broken nasal bones. The major neurocranial sutures appear to be shallowly interdigitated and unsegmented. T h e posterior root of the zygomatic arch expanded into a shelf, and it seems that the arch itself would have been short, circumscribing a small temporal fossa. Basicranial flexion appears to be extreme, and the large, round foramen magnum lies far forward. T h e relatively tall and pointed canine teeth are remarkable in having a much longer mesial than distal margin, the latter being curved to produce an almost hooklike profile. There is also an apparently pronounced buccal

. .-^^^^^^b^c^xX^y

-;v,5j

OVERVIEW

499

cinsulum that terminates in a distal stvlclike structure. The preserved RP2 paracone and protocone appear quite tall and well-separated, and on M2 and the much smaller M 3 , there appears to be a distinct postcingulum terminating in a swelling at the distobuccal corner of the tooth. Ml— M2 are subequal in size and the M3 is much smaller, especially m/d. The lower jaw D2735 that is apparently associated with the D2700 cranium has a more worn dentition and fewer preserved teeth than the D211 mandible published by Gabunia and Vekua in 1995. However, based on published illustrations it seems plausible that, despite minor differences, both represent the same morph. For example, when viewed from the front both appear to have long bony swellings running up and back from the inferior margin of the mandible to just in front of and below the mental foramina that lie below P I . The anterior dentition is large in D211, and would also have been in D2735. The P i s in both are dominated by the protoconids, and lack metaconids. The protoconids are steep lingually, and are ringed at their bases by thick cingulids bearing small conulids. In both, P I is longer m/d than the P2. Although we have not vet been able to describe the lower jaw D2600, the holotype of Homo georgicus, we have had the opportunity to see it. As Gabunia et al. (2002) remark, this is a large mandible with large teeth, unfortunately heavily worn. These authors emphasize the tall, thin symphyseal region in arguing that this specimen should be allocated to Homo; but unlike other hominids it has a very tightly curved and steep postincisal plane with a large and spikelike single genial tubercle close to the inferior margin. Further, the shape of the corpora and the tall rami, together with the large canine with its long, curving root and the large, long M3s, could be interpreted to suggest that the large-bodied hominoid represented here was not necessarily a hominid. Certainly, this specimen is sharply distinguished in its morphology from the much smaller D211 and 2735, as its allocation to its own species by Gabunia et al.'suggests. Thus two highly distinctive mandibular morphs are certainly present in the Dmanisi assemblage. . The teeth of D211 are all present and relatively unworn, and are readily compared to those of KNMER 992, the holotype of Homo ergaster. In D211 the premolars are rounded on their lingual surfaces, whereas in ER 992 all check teeth arc long and narTow and are straight lingually. The PI of D211 has a

500

II OM IN ID G l l A N l O D E N T A L M o R P I I O LOG I E S : A.N

centrally placed protoconid, mesial and distal foveae lying lingually, and a vertical lingual pillar descending from the protoconid apex. In ER 992, in contrast, the protoconid is mcsially shifted and a horizontal crest connects it to a compressed metaconid lying opposite. A large mesial fovea and a much larger talonid basin lie on cither side of this cristid. The P2 in D211 is smaller than the P I , especially m/d, and its small metaconid, lying opposite the centrally placed protoconid, is ringed by a cristid that runs from the mesial side to the distal side of the protoconid. The P2 in ER 992 is only slightly shorter m/d than the P L The protoconid and the small metaconid opposite it are quite mesially placed, with melded bases, and there is a tiny mesial fovea in front and a much larger talonid basin behind. The molars of D211 are ovoid, and decrease in size markedly from M l to M 3 . All three bear large paraconid shelves that intrude between the bases of the quite mesially placed and subequally sized protoconid and metaconid. M l has a distinct metastylid squeezed between the metaconid and hypoconid; this region is wrinkled and distinct in A12—M3. The molars in ER 992 are more worn, but M 1 - M 2 are long and roundedly rectangular and the molars do not decrease in size posteriorly. The metaconid is larger than the protoconid, especially m/d, and the base of the hypoconid is waisted to produce a conulid-like extension to the midline. However, as in D211 (and numerous other hominids), there is a paraconid shelf wedged between the protoconid and metaconid. The M l of D211 bears a buccal cingulid around the protoconid and a notch between the hypoconid and hypoconulid, and the hypoconulid on all molars is fairly buccally placed. In ER 992 the hypoconulid on M 1 - M 2 (and apparently also on M3) is centrally placed and there is a broad notch between it and the hypoconid. There is no cingulid on M l . All in all, ER 992 and D211 are highly distinctive from one another, and certainly represent separate morphs. We have already noted that the Kenyan fossils KNM-ER 992 and W T 15000 differ from each other dentally, and it is also evident that W T 15000 differs from D211 in a large number of respects. Whereas the lower incisors of D211 are tall and narrow, those of W T 15000 arc short, broad and spatulatc. The canine of D211 is pointed, with a fairly straight lingual side with narrow mesial and distal vertical lingual fovea. This tooth in W T 15000 is short and rounded at the tip, with huge lingual swellings and broad mesial and distal lingual foveae. The PI of D211 is

OVERVIEW

dominated by the protoconid, whose lingual side is steep and whose base is ringed by a large cingulid enclosing groove-like mesial and distal foveae. The Pi of W T 15000 is rounder and bears a metaconid that is subequal to and level with the protoconid. There is a moderate mesial and a larger distal fovea that lie fore and aft of the protoconid-metaconid pair. The P2 in D211 is narrower m/d than b/1, and the centrally placed protoconid and metaconid lie opposite one another. The mesial fovea is small and the distal fovea is moderately sized. In W T 15000 the P2 is essentially round, with mcsially placed protoconid and metaconid and moderately small mesial and relatively large distal foveae. In D211 M 2 is noticeably smaller than M l , whereas in W T 15000 the M2 is slightly larger, especially m/d, than the M l . The molar hypoconulids are buccally placed in D211, but lie centrally to lingually in W T 15000. Again, two clearly distinguishable morphs present themselves here. It may also be relevant to remark that, similarly, there are no significant similarities between D211 and the the lower molars of Homo antecessor from the Gran Dolina. The hominid assemblage from Dmanisi is thus of a relatively heterogeneous aspect overall, and at the morph-rccognition level none of its constituents can at present be shown to bear a compelling resemblance to claimed Homo erectus materials from either Africa or Asia, despite a few isolated similarities here or there. In short, none of the Dmanisi fossils can be regarded as belonging either to Asian Homo erectus or to the species containing its supposed African relatives. Other European fossils that have been associated with Homo erectus at one time or another include the calvaria from Ccprano, in Italy. This specimen is discussed in the next section of this survey, as are other fossils sometimes alleged to be Homo erectus such as the Arago hominids and the Maucr jaw.

MIDDLE AND LATE PLEISTOCENE HOMINIDS OF EUROPE EARLY MIDDLE PLEISTOCENE HOMINIDS A number of recent discoveries have pushed back the fossil evidence of the first appearance of hominids in Europe to close to a million years ago. From the Gran Dolina site at Spain's Atapucrca, for instance, has come a small but intriguing assemblage of

II O M I N I D

GKANIODENTAL

MOKi'iioLOGiKs:

fragmentary hominid fossils that have been assigned to the new species Homo antecessor. To these fossils \vc have as vet enjoyed only perfunctory access, and our remarks here are accordingly brief (but sec also below). Homo antecessor remains dentally quite primitive and it has been argued by Bcrmudcz de Castro ct al! (1997), on the basis of midfacial morphology, that this form may have been ancestral to both Neanderthals and Homo sapiens. However, to demonstrate this conclusively would require that //. antecessor be shown to constitute the primitive sister of a Neanderthal -sapiens clade that is united by demonstrable synapomorphics. This primitive species could not have possessed autapomorphies of its own. These conditions arc hard to fulfill on the basis of the available fragmentary evidence. For example, the one (juvenile) H. antecessor midfacial specimen known already has huge frontal sinuses, which would rule it out of the ancestry of both Homo sapiens and Homo neanderthalcnsis (if not of Homo heidelbergensis). Moreover, among other features of H. antecessor invoked by Bermudez de Castro et al. (1997) as resembling H. sapiens is an upwardly arcing inferior margin of the anterior root of the zygomatic arch that is delineated laterally by a blunt maxillary tuberosity. However, while this conformation is indeed seen in H. sapiens, it is also present in various Chinese specimens from Zhoukoudian Lower Cave, and to some extent also in the cranium from Dali. Further, in the juvenile midface of H. antecessor a curious depression lateral to the infraorbital foramen is formed by the eversion of the lateral lip of the inferior orbital margin. Again, though, this conformation is shared with Jebel Irhoud and some individuals of H. sapiens as well as with Dali and Jinniushan in China, and the thickened and everted inferior margin of the orbit is lacking in the single comparable adult specimen from the Gran Dolina. T h e backward profile tilt of the root of the infraorbital plane resembles that seen in H. sapiens, but is not detectable in the Chinese or Irhoud fossils. At the present state of our knowledge it is, moreover, impossible to know whether any of these characters is invariant in adults of the Gran Dolina and other populations, a lacuna of a sort that is all too common in our knowledge of extinct Homo. Similarly, while the double-arched supraorbital torus is commonly cited (Stringer, Hublin and Vandcrmccrsch, 1^84) not only as a distinguishing feature of Homo ntanderthalensis, but also as a character linking Neanderthals with the form represented by the Stcinhci m-

AN

OYKKYIKW

501

fossil (Schwartz and Tittersall, 1996a), it is also seen in the ATD-6 Gran Dolina juvenile upper face. Such observations emphasize that while it is possible to match individual derived characteristics of the Gran Dolina specimens with various other fossil humans, it is frustratingly difficult to know definitively which of these characters arc genuinely phylogenetically revealing. In our view, then, it is not possible at present to determine the exact phylogcnctic position of Gran Dolina //. antecessor, although there can be no question as to its validity as a unitary morph: a morph that, in our view, does indeed represent a species distinct from those with which its describers compared it. However, it is likely (as already noted by Hublin, 2001) that the Gran Dolina hominids arc not the only known rcprcscntivcs of this morph, and that they arc, indeed, complemented by other materials. Though differing from each other in size and robusticity, the three probably only slightly younger Tighcnif mandibles from Algeria appear to belong to a single morph that is distinguished most strikingly by the presence on the external midline of the mandible of a low, broad, vertical keel that broadens into a variably thickened inferior margin—one of the few structures comparable to a true "chin" currently known outside H. sapiens. Other mandibular features of the morph include very large mental foramina lying posteriorly under P2; swelling of each corpus below the entire cheek-tooth row; uniform b/1 thickness of the corpora throughout their length; and exceptionally smooth arcing of the anterior curve of the jaw as seen from below. And while the fragmentary Gran Dolina fossils do not provide a useful comparison to Tighenif in terms of mandibular features, dental comparisons arc instructive (Plate 36). t Both the Gran Dolina and the Tighcnif hominids share the following lower dental features: Pis and P2s with inwardly tilted buccal sides; Pis more truncated lingually than P2s; both premolars with thick cinKulids, which on the Pis arc separated from the base of the small mesially shifted mctaconid by a crease; P i s with a deep, pitlike mesial fovea and a more creaselike distal fovea; molars that are relatively long and narrow and distally rounded, and that bear a long bin b/1-oriented groove in front of the ^ M protoconid bases that lies far in from the mesul c lg 1 . tooth; . .i and A broad Ur^A hypoc hvnoconuhds straddling the of, the id line with greater buccal than lingual extension. extens^ m if unworn M 3 . in both groups the enamel is ven

O

^>02

H O M I N I D C K A N I O D K N T A L M O K i ' i i o i . o r . i K s : A N OVKKVIKW

deeply and extensively grooved; the same was probably also true for the M i s and M2s. Although extremely worn, the R canine is preserved in Tighenif 3; it would have been quite large, as is the less worn lower canine from the Gran Dolina. The alveoli for the canine in Tighenif 1 and 2 suggest a large root, as also seen in the Gran Dolina canine. All of these common dental features suggest that the Tighenif and Gran Dolina lower dentitions represent the same morph. This notion is not contradicted by available mandibular evidence; and if the combined morph corresponds to a distinct species, the name with priority for that species is Homo maurltamcm (Arambourg, 1954). Potentially hominid-yiclding levels of the Aurora stratum at Gran Dolina T D - 6 have as yet hardly been explored, and the recovery of further craniomandibular fossils that would shed further light on this question is eagerly awaited. As for other potential candidates, the younger Thomas quarry fossil from further west on the African Mediterranean coast is inscrutable, but does not belong to this group. As also noted later, its closest resemblances arc with the La Naulctte mandible from France, whose wider affinities are equally obscure. The Ceprano partial calvaria from central Italy is of approximately the same antiquity as the Gran Dolina material. Clearly, it cannot be compared to the Tighenif jaws, and it is adult and consists largely of different cranial parts from the Gran Dolina fossils. Nonetheless, in comparable regions it appears to be of different aspect from the Spanish/Algerian form. Like the Gran Dolina fossils, this specimen demonstrates that hominids had penetrated western Europe by about 800 kyr ago. But it seems unlikely that the two sites have produced the same hominid species, as has already been noted by Bcrmudcz dc Castro et al. (1997) and by Manzi et al. (2001). In some ways the posterior cranial profile of this specimen recalls that of O H 9, with a very distinctive angle between the occipital plane and the long nuchal plane. However, a closer comparison might well be with the tall supraorbital regions of the Daka calvaria from Bouri, in Ethiopia. In the Daka fossil, as in the Italian one, the anterior supraorbital surfaces do not twist supcrolatcrally as they do in other forms, such as Arago and Kabwe, to which Ceprano also invites comparison. Again as in Ceprano, the large supraorbital ridges of Daka appear to be continuing far down medially, toward a very inferiorly placed and sunken glabella. And in both the temporal lines also emerge fairly high up

and seem similarly textured. Seen from the side, the region in front of the mastoids lies far forward in Ceprano, below the vertex; also as in Daka the posterior root of the zygomatic arch slopes steeply down anteriorly, to enclose what appears to be a very small temporal fossa. In both specimens, too, lambda probably lay quite high. We have not seen Daka, and wc have seen Ceprano only briefly, but it seems reasonable at least to raise the possibility that these two penccontemporaneous fossils represent the same hominid morph. If this morph deserves species recognition, the name Homo cepnmensh (Mallegni et al.. 2003) has recently become available.

HOMO HEIDI:UU:RGI:NSIS AND ITS PUTATIVK R.KLATIVKS In 1908 Otto Schoetensack applied the nomen Homo heidclbcrgem'is to the virtually complete hominid mandible recovered from a gravel pit at Mauer, Germany (Schoetensack, 1908). In recent years it has become increasingly common to refer other fossils to this species (e.g., Tattersall, 1986; Rightmirc, 1990; Stringer and McKic, 1996). Such fossils derive mostly from the 600-300 kyr time range, and come from sites in Africa and Asia as well as in Europe. Most specimens in this category arc not directly comparable to the Mauer jaw, consisting as they do of cranial rather than mandibular components. I lowevcr, the hominid remains from the French site of Arago arc particularly valuable in providing an association between the type mandible and cranial remains, since they comprise elements from both upper and lower components of the skull. The corpora of the two betterpreserved Arago mandibles arc more gracile than those of the Mauer specimen, and their rami arc not as elongated anteroposterior^ as those of the latter. Nonetheless, wc arc impressed by the similarities m premolar and molar morphology between the Mauer and Arago 13 mandibles (Plate 37). Notably, the anterior teeth in both were rather large and the molar* long and ovoid; the P i s arc obliquely truncated mcsiodistally along their lingual surfaces, and arc thus more tapering mcsiodistally and elongate than the short, buccolingually wide and more ovoid P2s; the protoconids on the Pis and P2s arc centrally placed in both; on Pi the low lingual swelling lie* opposite the protoconid, while on P2 the mctaconid is mctially situated relative to the protoconid, and on both premolars the lingual swelling or cu*p is bounded by a tiny

II O M I N I I ) C R A N I O DENTAL M o i t I M I o L O U I E S : A N O V E U V I E \v fovea mcsially and a much deeper fovea distally. In the molars, M2 is larger than both M l and M 3 ; the protoconids and metaconids arc situated very mcsially on the crowns and in the same relationship to each other; M l shows evidence of a tiny trigonid basin, while this basin is more pronounced on M 2 - M 3 ; and on all molars the hypoconulid lies just buccal to the crown midline. In all molars the talonid basin is or was quite long mesiodistally and truncated buccolingually, with some evidence of enamel wrinkling. In the mandible itself, both specimens show a common configuration of the anteroinferior margins of the jaw, and also share excavated and rounded gonial regions, anteroposteriorly long coronoid bases, posteriorly decreasing corporal heights and tall but shallow infracondylar sulci along the posterior margins of the rami. Despite differences in a/p ramus length and various other details, we have no reservations in assigning the Mauer and Arago jaws to the same species, in which case it is also legitimate to use comparisons with the Arago cranial specimens, in particular the Arago 21 face and associated fragments, in determining the affinities of other hominid cranial fossils to H. heidelbergensis. Using Arago 21 and its associated parts as standards of comparison, several relatively well-preserved specimens stand out as candidates for membership in H. heidelbergensis. Foremost among such European specimens is the cranium from Petralona, Greece. Among African fossils the Bodo, Kabwe and Saldanha crania are obvious claimants; and from Asia the Chinese specimens from Dali and Jinniushan have also been considered in this role (Plate 38). All are broadly comparable in cranial vault size and in the proportions of the face relative to the braincase. In the following paragraphs, we will briefly look at these specimens, and others. See the appropriate entries in these volumes for substantiation and greater anatomical detail. T h e Greek specimen from Petralona is particularly reminiscent of the Arago 21 cranium in possessing a quite massive and broad lower face lying below hugelv developed and superoinferiorly very tall supraorbital margins that reach their maximum thickriess at about midorbit. T h e same is true of the Bodo, Kabwc, Saldanha and Dali crania and, to a lesser extent, of the Jinniushan specimens. In all of these fossils, the superior margin of the orbit is marked by a blunt edge above that demarcates the anterosupenorly twisting front surface of the torus from a posttoral sulcus beis hind. Similarly, in all of them the posttoral sulcus

503

nonetheless quite shallow. It should be noted, however, that there is considerable morphological variety as well. For example, while Bodo has a low nasal aperture with long nasal bones that curve concavely outward in profile, Arago, Petralona, Kabwc, Dali and Jinniushan show higher-placed nasal apertures with shorter and significantly less protruding nasal bones. At the same time Petralona, and especially Bodo and Dali, share relatively larger nasal apertures than the others. Sinusial inflation of the supraorbital tori as well as of the frontal bone behind them varies significantly within this group. Petralona shows the greatest degree of general sinusial inflation (even including a small sinus within the squama of the temporal bone), and its frontal sinuses penetrate posteriorly far into the frontal. In Kabwe, on the other hand, such inflation is much less extensive. This variation extends also to the inflation of the face, which is swollen in Petralona and probably also in Bodo by huge maxillary sinuses that alter the aspect of the entire infraorbital plane. In contrast, Kabwc, Arago, Dali and Jinniushan show hardly any swelling at all of the infraorbital region. Protrusion of the frontal lobes over the orbits is greater in Bodo and Arago than in Kabwe and Petralona, in concert with a more sunken cribriform plate that lies below the superiorly expansive orbital cones. Because the frontal lobes extend farther forward and more horizontally in Arago and Bodo, the clivus is flexed downward in these fossils more sharply than in Kabwe and Petralona, and the hypophyseal fossa is more clearly defined, with a more prominent dorsum scllae. There is also a clearer distinction between the anterior and middle cranial fossae. The degree of external cranial flexion in the Dali and Jinniushan specimens suggests that imaging these fossils would reveal closer resemblances to Arago and Bodo in their internal conformation. In the rear of the skull there appear also to be two basic morphologies in this group of hominid fossils. In Petralona and Dali the "occipital torus," which is undercut below but is not clearly defined above, runs transversely straight across the occipital for almost the fid! width of the braincase. In Kabwe, in contrast the " descends toward the midline similarly undercut torus to a peak in the region of the external occipital protub e r a n t giving a "bow-shape" to th.s s t „

r i S r P r o f i l e the Kabwe cranium contrasts w,.h In posterior pro

3U 4 *

IIOMINID C R A N I O D E N T A L M O R P H O L O G I E S : AN OVERVIEW

Petralona in having higher and more vertical side walls and a more rounded top. Of less complete or less wellpreserved specimens, Saldanha shares a basic supraorbital morphology with all members of this group. Among them it most closely resembles Petralona in its nuchal line morphology, though its nuchal plane is slighdy less horizontal than the latter's. The Narmada hemicranium from India shows a right supraorbital margin that is smoothly rolled to the back, strongly arced over the orbit and probably uniformly thick from side to side. The orbit itself appears to have been tall and ovoid, rather than subsquare with a straight superior margin. The partially preserved zygoma is relatively small and turned strongly back along the side of the skull; it also angles inward and down, suggesting a narrow lower face, and the frontal rise is quite steep. These morphologies do not appear to place diis specimen close to the group we have just discussed, though they are characteristic of some members of the Neanderthal clade (see later). The Verteszdllds occipital has a horizontal occipital "torus," and thus is reminiscent in this feature of Petralona. As also seen in the Saldanha specimen, the nuchal plane in the Verteszollos fossil is less horizontal than in Petralona. The Maba partial calotte also shows a steeper frontal rise than is typical of the latter grouping, with a more rounded R orbit and a different conformation of the continuously curved supraorbital region; in these features Maba is more comparable with Narmada. Both of these specimens are in turn comparable in these features to Neanderthals (Plate 39). Finally, we must mention the fragmentary Bilzingsleben hominids, which pose a particular problem because the two reconstructed individuals from this site appear to display significant differences from one another. In Individual 1, the supraorbital regions are tall superoinferiorly and smoothly rolled, and the orbital roof curves smoothly into the superior orbital margin, with a longer posttoral plane behind. In Individual 2, the supraorbitals are less tall, have a sharper corner from the orbital roof into the superior margin and the posttoral plane is shorter, with a steeper frontal rise. In the rear of the skull, Individual 1 shows a continuous and uniformly protrusive angulation from side to side right across the occiput, while the occipital fragment of Individual 2 shows a totally different conformation in which the superior nuchal line describes a sweeping curve from the left side to redescend well before the midline.

This brief overview of materials that have at one time or another been referred to H. beidelbergensis (or discussed in connection with it) emphasizes a fundamental structural similarity among most of them. At the same time, however, it shows that a lower-level morphological partitioning exists among these broadly similar forms, especially in terms of internal cranial features and occipital morphology. This difficult distribution of characters will have to be taken into account in future systematic analyses of this group.

T H E NEANDERTHALS AND RELATED FORMS For most of the past century many have chosen to discuss the Neanderthals within a generally linear schema of human evolution, regardless of whether the preference was to view these distinctive hominids as an independent species or to see them as a variant of Homo sapiens. Pre-Wurm European fossils that appeared to have some of the features typical of Neanderthals, but not all of them, were often referred to as "preneanderthals" or "protoneanderthals," or were accommodated into a "presapiens" construct (sec discussion in Tattersall, 1995). Examination of the morphological evidence presented in the first volume of this series points, however, to an alternative interpretation (see Schwartz and Tattersall, 1996a). In this alternative view, the Neanderthals and fossils resembling them were not simply a segment of a linear progression, but rather formed part of an endemic European hominid clade that had its origins perhaps at some time around 500 kyr ago. Homo mandertbalemu is simply the best-known and last-surviving member of this clade. The origin of the larger group is probably to be sought within the assemblage of fossil material often attributed to Homo beidelbergensis (sec earlier discussion), or among as-yct unknown related forms.

Morphologically, H neanderthalensis is well defined, and we also have a fair perspective on morphological variation within this species (sec particularly Schwartz and Tattersall, in press). European and western Asian specimens listed in Volumes 1 and 2 of this series with unquestioned Neanderthal attribution include: Amud, Archi, Biache, Columbcira, Engis 2, Fcldhofcr, Figucira Brava, Gibraltar (Devils Tower and Forbes* Quarry), Guattari, Hortus, Kcbara, Krapina, Kulna, La Chapclle, La Fcrrassic, La Quina, Lc Mousticr, Ochoz, Pech dc TAzc, Regourdou, Roc dc Marsal, Saccopastorc, St-Cesaire, Sakajia, Scladina,

II ( n U N , h Shanidar, Tahfin P1 Q* i spcvimen from EndanH ; "

C R A N , ( ) | , |

^TAL

MoiiriKiLooiBs:

AN OVBUVIKW

505

o : \

U c

SwmS

<°mbc

since not all comparable Lhrmgsdorr framcnts appear to show the same moramc mor phology. 1032/69 >iogy. l
fully ossified laterally; and a long, narrow foramen magnum. In the mandible there is a rctromolar space; a sigmoid notch that is deepest posteriorly; a large medial pterygoid tubercle; a "cut-off" gonial angle; symphyseal hone that is thinner seen from below than the bone of the corpora on either side; and a sigmoid notch crest that terminates medial to the lateral extremity of the condyle. In the dentition, the lower molars (deciduous and permanent) have talonid basins plus distinct trigonids, making them relatively long and narrow. Molars have relatively complex occlusal surfaces, with ccntroconids on the lower molars (and second deciduous lower molars), and centroconcs in the upper molars. Occlusal surfaces are well defined by blunt crests and are relatively constricted, with inwardly sloping sides. Another possible autapomorphy is a large paracristid separated by a crease from a lingual swelling at the base of the protoconid. Various European specimens from the middle Pleistocene share some of these characteristics of Homo neanderthalensis, but not all of them. Notable amongst these are the Stcinheim, Rcilingcn, Atapucrca/ Sima dc los Hucsos, and Montmaurin fossils. Among Neanderthal features Stcinheim possesses the smoothly rolled and separately arching supraorbital margins over "aviator-glasses" orbits; the large nasal aperture that had a distinct prenasal fossa between the lateral and spinoturbinal crests; angulation along the anterior squamous suture; and a (faint) suprainiac depression. Plastic deformation of the skull renders current basicranial morphology and the braincase profiles unreliable, but Neanderthal-like long, horizontal parietomastoid and anterior lambdoid sutures are present. *Inside- the nasal aperture is a slight vertical thicksent. ening of the lateral nasal wall which appears to correspond to the medial projection of Neanderthals. ipona to uic ii.^u.... r—j—-—He -Iowcvcr, the Stcinheim specimen lacks the Pu > mi midfacc and the markedly retreating zvgomas that sh tion of eharactenst.es, we bchew. « j Kard the Stcinheim spec... en * a past,

^ t,

The Rcilingcn par a alu c petrosal pncumat.zat.on du. _ M depression, the horizontal « ,.„,„ o f l ! e d only below ^ J ^ s m o o d . l y ro cd the cctotympan.c tube

506

HOMINID CRANIODENTAL MORPHOLOGIES: AN

rear-viewed profile of the braincasc that are typical of Homo ncanderthaknsis. Indeed, it appears Neanderthal in most of its preserved characters. Unfortunately, it is missing most of the features that ally Stcinheim with the Neanderthals, while the Steinheim specimen is distorted in most of those traits best preserved in Rcilingen. It is thus hardly possible at present to resolve the phylogcnctic position of Stcinheim and Reilingen vis-a-vis each other and the Neanderthals, beyond saying that all appear to belong to the same clade. The many hominid fossils from the Atapuerca site of the Sima dc los Huesos appear to form a relatively homogeneous assemblage, of which we have only been able to record Skull 5 in any detail at all. Based on this specimen, the Sima hominid possesses a variety of Neanderthal-like morphologies. In the cranium these include the bilaterally arced supraorbital tori with tall, rounded anterior surfaces; a large nasal aperture with a prenasal fossa bounded by a continuous internal margin; some anterior projection of the frontal processes in the region of the nasal aperture; orbits of "aviator-glasses" shape; angulation of the anterior squamous suture; a long, horizontal parietomastoid suture; ectotympanic tubes not fully ossified laterally; and a pitted suprainiac depression. In the mandible, Skull 5 shares with Neanderthals a series of medial pterygoid tubercles and a sigmoid notch crest running just lateral to the midline of the condyle. We have been unable to examine the teeth in the Sima series, but from illustrations it appears that the preserved upper molars are generally similar to those from Steinheim in showing a strongly reduced upper third molar and some elongation of first and second upper molars that possess expanded hypocone regions. Skull 5 is unlike Neanderthals in these features: an uninflated infraorbital region (though not as flat as Steinheim); the absence of an occipital "torus" well defined by nuchal undercutting; vertical braincase sides that peak superiorly when seen from behind; deep zygomatic arches; a midface that does not retreat sharply, a face that does not taper inferiorly, and inferior margins of the anterior zygomatic roots that are angled farther out laterally; and the absence of a distinct anterior lambdoid suture. Puzzlingly, this specimen has in common with H. sapiens the segmented and (in its C2 segment) deeply interdigitated coronal suture that is primitively lacking in Neanderthals. Given this pattern of resemblance it appears permissible to regard the Sima population as representing the

OVERVIEW

sister taxon of the Neanderthal-plus-Steinheim-plusReilingen clade. Where exactly the Montmaurin mandible fits into this picture is not entirely clear, though this specimen clearly shares with the Neanderthals features such as its large medial pterygoid tubercle; a (very small) rctromolar space; ovoid lower molars with narrow well-defined talonid basins; and an extension of the metaconid into the talonid basin in the position of a centroconid. Given the pattern of resemblances sketched in the preceding paragraphs among the members of this European hominid group, it makes little sense to analyze them in terms of "Neanderthal" vs. "PreNeanderthaT features. Instead, it appears that the European hominids of the past half-million years form an endemic and diverse clade that is probably linked with at least some of the forms that are currently included in H. heidelbergensis. H. ncanderthaknsis is, as we have already suggested, simply the best-known and latest-surviving member of this clade. It would, further, be interesting to investigate whether or how such forms as Maba and Narmada, which also boast large and smoothly rolled supraorbital tori, fit into this picture. In both of these fossils what is preserved of the torus arcs over the orbit; and the zygoma, rather than being vertical, is angled inward inferiorly, suggesting a narrow midface. It is also worth noting in passing that the Guomde hominid, while not being at all typically Neanderthal, is broadly reminiscent of this group in its brow shape; by the same token, it departs in this feature (and in external petrosal configuration) from the H. sapiens conformation. Thus, at the vet}' least, we are glimpsing here yet more morphological and potentially taxic diversity that future studies will ultimately have to address.

HOMO SAPIENS AND "ARCHAIC HOMO SAPIENS "Archaic Homo sapiens" has become a fixture in the paleoanthropologies literature, largely because it provides a convenient if untidy receptacle for an unwieldy assortment of fossils. Within the linear human evolutionary construct favored by the Evolutionary Synthesis, this assortment contains virtually all of the hominid fossils that date subsequent to H. ercctus, and

I I O M I X I I , CRAXIODEN-TAL S

M OKiMiOLocna*:

before anatomically modern Homo sapiens. While it certainly supported the elegant simplicity of the evolutionary progression preferred by most paleoant h r o p o l o g y of the mid-to-late twentieth century the major role of "archaic Homo sapiens' has been to eliminate the need to examine closely the morphological variety existing among the fossils it embraced. Once again, though, it seems inevitable that this variety must eventually be confronted, and since H sapiens is the sole surviving species of its once-diverse clade, it seems to make sense to start with ourselves.

OVEKV.EW

been assigned to HL what should b c d o n ^ E ; not propose to JZ< u

507 automati° «= ' ' ^ °f s **" ^ >stCmatically. We do

T

f 5 S , l s t h a t hav

prCSented in Volu and 2 of W ^ ™s 1 and 2 of this series, only the follow™ fit this narrower morphological definition of H. L L in

what HOMO SAPIENS AND SUGGESTED CLOSE RELATIVES With some six billion examples in the world today, one might expect Homo sapiens to be an exceptionally easily diagnosible species. Alas, this has proven not to be the case. From a foundation based on living humans, our species has gradually been expanded, from Huxley (1863) on, to embrace what is by now a bewilderingly diverse assortment of morphologies. In this process "archaic Homo sapiens" has been an indispensable ingredient. But if we are to make any progress in sorting out this variety, it will be essential to acknowledge that such diversity must at least to some extent be taxic as well as morphological. Largely because the attention of biological anthropologists has traditionally been drawn to what divides our species rather than to what unites it, H. sapiens has managed to elude satisfactory morphological definition. Recently we have at one time or another pointed to nine features of the skull that appear among hominoids to be autapomorphic for H. sapiens (Schwartz and Tattersall, 1996a, 2000a,b): extension of the tall, sheetlike vaginal process to the lateral margin of the ectotympanic tube; the approximation of this process to the mastoid process; extreme lateral placement of the styloid process, the stylomastoid foramen lying posteromedially at its base; the narrow, high occipital plane of the occipital bone; the retention into the adult of a discernible arcuate eminence; fully segmented cranial sutures, with some segments deeply interdigitated; the bipartite brow; symphyseal region of the mandible thicker, as seen from below, than the corpora on either side; and the unique inverted-T-shaped chin. Some additional apomorphies might include an unclosed-off subarcuate fossa ana also, as suggested by Arsuaga et al. (1997), an infraorbital plane that tilt down and back from the inferior

AN

prcservcd: Abr.

p a t

j7j

C!?M n ^ ' c C h a n C c l a d c ' C o m b c Capelle Cro-Magnon, 1 n • i J- Dar TY cs Soltane, —*•"«., Dolni i^oini Vestonicc, vestonicc, Ends Lngis 1, Gnmaldi, Hahnofcrsand, Haua Ftcah, Isturitz, Jcbcl Qafeeh (1, 2, 9 and 11), Klasies River Mouth (one specimen only: AP 6222), Liujang, Mladec, 1 avlov, Prcdmosti, Svitavka, Tuinplaas, Vclika Pecina Vogelherd, Wajak, Zhoukoudian Upper Cave and Zlaty Kun. Most of these hominids have Upper Paleolithic (or Late Stone Age) associations, and are relatively recent in date. If we define H. sapiens on the basis of the apparent apomorphies we have enumerated, we are left with a relatively large contingent of forms that have in the past been identified as "modern Homo sapiens" (more or less), but that fall short of this narrower definition. These hominids include: Border Cave 5, Boskop, Cave of Hearths, Fish Hoek, Klasies River Mouth (almost all specimens, see earlier), Omo Kibish 1 and 2, Singa, Jebel Qafzeh (other than those given earlier) and Skhul (Plate 40). Many of the fossils mentioned compose a distinct South African group that does not possess bipartite brows or a keeled external symphyseal region of the mandible. This group includes the Klasies River Mouth, Fish Hoek, Boskop and Border Cave specimens just noted, and possibly Cave of Hearths, though this last fragmentary specimen might fit the H. sapiens definition were more of it known. In Fish Hoek there is a nonbipartite supraorbital region, large fronted bosses and no keeling of the mandibular symphysis (though L e is a broad median swelling). Further the vaginal proce and stylomastoid pit do not conform to the

508

IIOMINID CllAKIODEKTAL

M o RPII O LOG I ES : A N OVERVIEW

show minor midline swelling of the external symphysis low down, but there is no "chin" as strictly defined (see Schwartz and Tattersall, 2000b). The single supraciliary element shows no suggestion of a distinct glabellar butterfly or of a retreating lateral plate. The Border Cave 5 mandible is small, with a swelling low on the symphysis, but is without a detectable keel. This particular array of craniomandibular conformations clearly warrants closer analysis, but it is already evident that in this group we are not dealing with H. sapiens exacdy as it is familiar to us today. From further north in Africa, the Omo 1 reconstructed cranium resembles H. sapiens in its tall occipital plane and in having a lambdoid suture that peaks at lambda. It is distinct from H. sapiens, however, in that the occipital plane is undercut by a transverse horizontal sulcus; the mandible is Klasies-like in the symphyseal region; the supraorbital margin thins laterally beyond midorbit, but thickens again toward the zygomaticofrontal suture; and that possibly there was a large retromolar space. Omo 2 may or may not have a bipartite brow, but it fails in the other basic H. sapiens characters. Additionally, the frontal poles did not extend over the orbits and the subarcuate fossa is closed off. The Singa skull has extremely swollen parietal eminences, cf. Boskop, and lacks bipartite brows. There is a long, horizontal parietomastoid suture, and the squamosal is primitively long. The vaginal process terminates medial to the styloid region, and the ectotympanic tubes are very short. The occipital is tall, but it is also broad and its nuchal plane undercuts the occipital horizontally, straight across. The subarcuate fossa is not closed over and the frontal lobes penetrate forward all the way over the orbital cones. Only the last two characters mentioned are derived features that overlap with H. sapiens, and we are clearly not dealing with our own detailed morphology here. The Eliye Springs cranium from Kenya resembles the Boskop morph in its relatively small face combined with a long but also very broad cranium. None of these eastern African fossils, any more than those those from South Africa just discussed earlier, is easily interpreted as an early variant of//, sapiens as we know it today. The Mousterian hominids of the sites of Jebel Qafzeh and Skhul have long been regarded as lying on the very edge of modern H. sapiens—if, indeed, they are not already there (see Klein, 2000; Wolpoff, 2000). However, most of them—including all of those from Skhul—do show substantial morphological peculiarities when viewed from this perspective. In

the Skhul population the brows are continuous from side to side and are rather barlike, in what is apparendy an autapomorphic conformation. In Skhul V (as in H. sapiens) the vaginal process contacts the mastoid process on one side. However, in contrast to H. sapiens there is a long parietomastoid suture, there is a mandibular symphyseal bulge rather than a keel and seen from below, the mandibular bone is more or less even in thickness across the symphysis and on to the corpora. There is a retromolar space and a large, forwardly jutting face. The lower third molar is large and long, and the ectotympanic tube is short and incompletely ossified laterally. The lower first molar of Skhul I has a primitively huge trigonid basin, and, as in Neanderthals including Tabun C I , the very large talonid basin possesses a deflecting wrinkle (a feature rarely seen in living H. sapiens). As noted previously, the Jebel Qafzeh hominids fall into two groups. Qafzeh 1, 2, 9 and 11 can be identified as / / . sapiens, but the rest cannot: certainly not H. sapiens as we are familiar with this species today. These latter Qafzeh specimens all show superior orbital margins that are continuous across glabella and are not bipartite; the vaginal process fades out before reaching the meatus; the styloid processes are very medially placed; and the stylomastoid foramina lie lateral to those processes. T h e superior nuchal line rises slightly higher laterally than at its midpoint, but is barely raised along its length. In the mandible, much as in Skhul, there is a teardrop-shaped bulge low down on the external symphysis, but no keel. Such morphologies serve to distinguish these Levantine Mousterians clearly from H. sapiens.

O T H E R MEMBERS OF THE "ARCHAIC HOMO SAPIENS' GROUP FROM THE LEVANT AND AFRICA We have covered under other rubrics some of the specimens previously assigned to "archaic Homo sapiens. However, there are several additional important specimens, mainly from Africa, that we have not yet addressed. These include the Israeli frontal from Zuttiyeh; the Florisbad anterior cranium from South Africa; the Ngaloba and Ndutu crania from Tanzania; and the Jebel Irhoud and Dar es Soltane crania from Morocco. Though other comparisons have typically been made, the Zuttiyeh hominid shows several Neanderthal resemblances. Thus the anterior squamosal suture is elevated, demarcating anterior and posterior

II OMINIH C U A N , O M E N T A L M o K I M I O L O C i l E S : A N O V E R V I E W temporal fossae, and the frontal rises well posterior to the smoothly rolled supraorbital tori that diminish only slightly laterally. Glabella is flat relative to nasion, and the nasal bones arc projecting. The maxillary sinus invades the body of the zygoma and the medial orbital wall, and the sphenoid sinus is more extensive than in //. sapiens. The projecting malar sweeps back, and the preserved orbit is of "aviator-glasses" shape. There seems to be little reason to broaden out comparisons further than the Neanderthals in determining the affinities of this specimen. The Florisbad fossil lacks a bipartite brow, having instead a continuous supraorbital surface that thins laterally. The coronal suture is lightly, and the sagittal suture deeply, interdigitatcd. This latter feature yields some similarity to H. sapiens, as does the backwardly sloping infraorbital plane. However, in general, the form of the face as reconstructed is not particularly H. sapiens-WkCj having an "aviator-glasses"—shaped orbit and a very broad nasal aperture. This individual could be a member of a species (Homo helmet Drcyer, 1935) that is related to H. sapiens, though it is not necessarily an extremely close relative. More material of this form is clearly required. The Ndutu partial cranium may need further reconstruction that would make it more "modernlooking" than it currently is, but there is no evident reason to include it in H sapiens, even as an archaic version. The left supraorbital torus is continuous and moderately thick, and it would have projected up and forward (much as in K N M - E R 3733), while the frontal apparently rises close behind a narrow posttoral sulcus. T h e parietomastoid suture is relatively long and horizontal, and the occipital plane is relatively broad. The junction between the occipital and nuchal planes is delineated not just by the highest nuchal line, but by a horizontal depression that is continuous across its upper surface. Still, the posterior portion of the occipitomastoid suture lies vertically, truncating the maximum width of the nuchal plane. This is a shared possession with //. sapiens, though it is a conformation found in O H 9 as well. The Ngaloba (LH18) cranium is long and narrow, with a very long frontal anteropostcriorly; and in front profile the braincase peaks slightly along the sagittal suture. However, the supraciliary regions, although relatively thick, do bear shallow grooves on their anterior surfaces that run laterally up and away from the equally shallow supraorbital notches. W h a t is apparently a broad glabellar butterfly is hence undercut by a

509

latcral plate, yielding a bipartite supraciliary conformation even if one that is not exactly like the typical H sapiens bipartite brow. As in H sapiens, the lo\ ow vaginal process continues to the lateral edge of th e cctotympanic tube (which, however, is short); but untin like what one sees in H sapiens this process does not contact the mastoid. The styloid process lies quite far medially, and the stylomastoid foramen lies well away from this process. Internally, the petrosals bear welldefined arcuate eminences (as in H sapiens), and the subarcuatc fossa is not entirely closed over. The lambdoid suture rises steeply from astcrion, but curves smoothly across lambda. This specimen thus bears an intriguing combination of similarities to, as well as differences from, H sapiens. However, it is doubtful that it can usefully be considered a variant of the latter, even though it is clearly a potential relative. The crania Jebcl Irhoud 1 and Dar cs Soltane, from Morocco, have both been rather vaguely considered as Neanderthal relatives or as somewhat "archaic" H. sapiens. They resemble one another in a variety of features that include "aviator-glasses" orbital shape; a relatively broad intcrorbital region; moderately short, laterally facing frontal processes of the maxilla, with some noticeable hypcrostotic activity along the zygomaticomaxillary suture; supraorbital tori that arc continuous between the R and the L zygomaticofrontal sutures, which are overhung by the torus on both sides; and a glabellar region that noticeably overhangs the nasion. The supraorbital torus of Jebel Irhoud 1 is uniformly thick across its width, and has a mildly sinuous curve as it arcs slightly over the orbits and dips over the glabellar region. This curve is more accentuated in Dar es Soltane, not so much by the arc over the orbits, but by the tact that the tori over the orbits are taller s/i, with consequently higher superior margins, whereas in Jebel Irhoud 1, the anterior face of the torus is more smoothly rounded. Most of these features, especially all the features of the nonbipartitc, smoothly continuous brow, combined with the overhanging* of the zygomaticofrontal sumres bilaterally ancUhc nasofrontal suture centrally, are distinctly different from what is found in H sapiens. And in the D ir cs Soltane specimen, the flat anterior surfaces ot the supraorbitals arc quite reminiscent ot what is seen in Homo beUelbergensis. Seen from behind, the Jebel Irhoud 1 cranium is extraordinarily wide and low, with a smooth curve over the top and a broad and downwardlv arcing, interiorly delineated superior dial line'that runs completely across the occiput to nu

510

H O M I N I D C R A N I O DENTAL M O R P H O L O G I E S : A N

terminate just above astcrion. As a result the nuchal plane is very strongly demarcated from the occipital plane, and lies very low. Despite some vague resemblances to Neanderthals these crania clearly do not belong to that group; and while they share a small lower facial region with H. sapiens, there docs not appear to be any particularly close affinity to our species either. Certainly, there seems to be little justification for considering them to be "archaic" versions of H. sapiens. In the case of the Jebcl Irhoud 3 juvenile mandible, a similar conclusion seems to apply. Seen from below, the jaw is uniformly thick from side to side, and it is flat and straight across the symphyseal region. Seen from the side the symphyseal region descends vertically from the alveolar margin, with a faint bulge into the inferior margin. From the front, well below the superior margin and slightly above the inferior margin, is seen a small, triangular region of swelling in the midline, which does not extend upward in a keel. On the R side is an upwardly angled and fairly large and deep depression; on the L there is a more horizontal and inferiorly placed depression. The inferolateral parts of this triangular structure do not thicken and/or terminate in tubercle-like structures. Clearly, this is not a true chin. The M i s are sufficiently unworn to indicate a morphology' that is distinct from that of either H. sapiens or H. neanderthalensis. The M i s are large and ovoid, and still preserve signs of deep, thick crenulation. The cusps are large and distinct, particularly the hypoconulids, which are huge, subtriangular structures that occupy most of the distal portion of the tooth and extend strongly lingually, to lie low at the base of a very small but distinct entoconid. The foregoing discussion makes it evident why the search for a potential direct ancestor of//, sapiens is so frustrating. If, for example, we seek evidence in the hominid fossil record of the origin of the characteristically H. sapiens chin, we find an early expression of such a structure only in one mandibular specimen from Zhoukoudian (ZKD 22687), which has a hint of both a keel and a mental trigon (Schwartz and Tattersall, 2000b). Otherwise, apart from those specimens that we have already explicitly identified as modern H. sapiens, we find a symphyseal keel solely in the three mandibles from Tighenif, only one of which shows any expansion of this structure at the inferior margin. Similarly, the search for an antecedent of the bipartite //. sapiens supraorbital configuration yields few candidates

OVERVIEW

beyond the grooving of the brow in LH18 (which also possesses a definitive arcuate eminence on its petrosal as well as a patent subarcuate fossa). At the be^innin? of this study we had expected to find that hominid fossils would sort into distinct clades, within one of which H. sapiens could be accommodated. In the event, this has not turned out to be the case. Instead, H. sapiens appears in many ways to be an outlier among all of the hominid forms we have examined.

CODA Paleoanthropology has plenty to congratulate itself upon as it closes on the halfway point of its second century. Its database—the human fossil record—has expanded beyond all expectations, and this growth has been accompanied by a remarkable increase in the sophistication and variety of the techniques available for the analysis of that record. Nonetheless, our science still labors beneath the heavy hand of a received wisdom that is becoming threadbare as an organizing paradigm. There is no doubt in our minds that, if the hominid fossil record that has been laboriously unearthed over the last one hundred and fifty years were to be discovered all at once tomorrow, the resulting picture of hominid phylogeny would look completely different from any that students are taught today. When we undertook this project of documenting the human fossil record, we had hoped to be able to conclude this fourth volume in our series with a review of hominid systematics that would serve as an adequate framework for the larger-scale understanding and interpretation of the many fossils we have been privileged to examine and describe. Alas, it is clear that we have fallen well short of that initial ambition, for in the process of compiling these volumes we have encountered what for us, at least, was an entirely unexpected morphological variety in the hominid fossil record: a variety that is inadequately described or organized by any of the constructs of hominid systematics that are on offer today, including our own. Indeed, although it has been satisfying to make many unexpected connections among sites, we have been litdc short of floored by the diversity we have come across. And although wc have made many comparisons in our concluding remarks, and have suggested morphs in the site entries, all wc can claim to have done here is to have scratched the surface ot this

II " M I N I D

GUAXIODENTAL

J M OIUMIOLOCSIEB:

diversity. Nonetheless, we hon#» t W P h a t o u r su i , u- i -ii • t ggcsted morphs, which wiU without question require a R reat deal of refinement in the future, will serve as a useful starting point for others carrying out new analyses. We thus do not claim any definitiveness for the rudimentary awareness that we have developed of the morphological complexities that characterize the history of the hominid family. And we wish most especially to emphasize that we do not necessarily equate all or even many of the morphs that we have tentatively identified with the historically individuated biological entities we know as species. But we do believe that many familiar paleoanthropologies systematic constructs have outlived their usefulness. It is becoming clear that any substantial progress in paleoanthropology will have to involve abandoning traditional scenarios of human evolution, and will require rethinking the structure of the human fossil record from the ground up. Tinkering, in our view, will not do the trick. Systematics is usually regarded as a rather humble branch of biology, and one in which many apparendy consider it sophisticated to feign a lack of interest: "YouYe only arguing about names." T h e almost universal urge seems to be to pigeonhole new fossils as quickly and as permanently as possible, so that everyone can get on with the really interesting stuff. In reality, however, basic species recognition provides the framework on which ail of the other more complex and interesting evolutionary formulations—cladograms, evolutionary trees, scenarios of adaptation, ecological stimulus, evolutionary pattern and so forth—depend (seeTattersall and Eldredge, 1977). And it is at the very least clear that the systematic framework that currently underpins our notions of human evolution is inadequate. It is hard to abandon one's cherished presuppositions, but we can only embrace the idea of progress in science if we accept that some at least of what we believe today is wrong, or that our current notions are in some way incomplete. Despite rumors to the contrary, none of us is writing for the ages. And it is from this perspective that we have offered this brief concluding review to this essentially documentary work.

OVERVIEW

511

J Ct a l 1 9 9 7 PU ' S i z c v a r i a t i o n in Middle 1 l c l sf' tocc* n c J* humans. Science 277:1086-1088.

Arsuaga J. L. ct al. 1999. The human cranial remains from (3-4). 431 " 4 L ° W C r

Plc lSt0CCnC S i l e

'

' ^ ""'"'

EvoL

A

Ar N u, B -T al* 2 0 0 2 ' R e m a i n s o f Hof»° <«'«' from Bouri, middle Awash, Ethiopia. Nature 416: 317-320. Bcrmudez dc Castro, j . M. c t al. 1997. A hominid from the lower 1 lcistoccnc of Atapucrca, Spain: possible ancestor to Ncandcrtals and modern humans. Science 2761392-1395. Black, D. 1927. On a lower molar hominid tooth from the Chou KouTien deposit. Palaeont. Sin. Scr. D 7:1-9. Blumenschinc, R. et al. 2003. Late Pliocene Homo and hominid land use from Western Olduvai Gorge, Tanzania. Science 299:1217-1221. Braga, J., E. Crubczy and M. Elyaqtinc. 1998. The posterior border of the sphenoid greater wing and its phylogcnetic usefulness in human evolution. Am. J. Phys. Anthropol. 107:387-399. Brunct, M. et al. 2002. A new hominid from the Upper Miocene of Chad, Central Africa. Nature 418:145-151. Chavaillon, J. and Y. Coppcns. 1975. Decouvcrte d'hominide dans un site acheulecn de Melka-Kunturc (Ethiopie). Bull. Mem. Soc. Anthropol. Paris 2 (scr. XIII): 125-128. Clark, W. E. le Gros. 1940. Observations on the anatomy of the fossil Australopithecinae./.^/w/. 81:300-333. Day, M. H. 1986. Guide to Fossil Man, 4th ed. Chicago: University of Chicago Press. Eldrcdge, N. 1979. Alternative approaches to evolutionary theory. Bull. Carnegie Mus. Nat. Hist. 13:7-19. Eldrcdge, N. and I. Tattersall. 1975. Evolutionary models phyloecnetic reconstruction, and another look at hom.md phyloecny. In: Szalay, F. S. (ed.), Approaches to Parnate Paleobiology. Basel: S. Karger, 218-243. Fenruson, W. W. 1984. Revision of fossil hominoid jaws S h e Plio/Pleistocene of Hadar in Etbopia, including a new species of the genus Homo. Plates 2,. 519-529. W W 1989. A new species of the genus V T*°l\lcu ft mat s: Hominidae) from Plio/Ple,-

F Race. c

37

Asfaw B. ct al. 1999. Australopithecusgarhv. a new species of early hominid from Ethiopia. Science 284: 629-635.

30:223-232. \\i W 1995. A new species ot the genus

REFEERENCES Alexccv, V. P. 1986. The Origin of the Human Moscow: Progress Publishers. Arambourg, C. 1954. LTiominicn fesilc de (Algeric)C. R.Acad. Sci. Paris 239: 893-895.

A

AN

}J

l K e f i S S c ) /T3f69S-,1C'StOCCne

GAunia. L. and A. \ e U U from Dman>si, east Otorgi-

^5Q9_512.

512

IIOMINID

GKANIODENTAL

MOIUMIOLOGIKS:

Gabunia, L. ct al. 2000a. Earliest Pleistocene hominid remains from Dmanisi, Republic of Georgia: Geological setting, and age. Science 288: 1019-1025. Gabunia, L. ct al. 2000b. Dccouvcrtc d'un nouvel hominide a Dmanissi (Transcaucasic, Gcorgic). C. R. Pale'ovol. 1: 243-253.

AN

OVERVIEW

Locke, R. 1999. The first human? Discovering Archaeol 1 (4): 3 2 - 3 9 . Mallegni, F. et al. 2003. Homo cepratiensis sp. nov. and the evolution of African-European Middle Pleistocene hominids. C. R. Palevol. 2:153-159.

Grinc, F. 1993. Description and preliminary analysis of new hominid craniodcntal fossils from the Swartkrans Formation. TransvaalMus. Monogr. 8: 7 6 - 1 0 7 .

Manzi, G., F. Mallegni and A. Asccnzi. 2001. A cranium for the earliest Europeans: phylogcnctic position of the hominid from Ccprano, Italy. Proc. Nat. Acad. Set. (USA) 98 (17): 10011-10016.

Grinc, F. and J. Franzcn. 1994. Fossil hominid teeth from the Sangiran Dome (Java, Indonesia). Cour. Forschungsinst. Senckcnberg 171: 7 5 - 1 0 3 .

JMayr, E. 1950. Taxonomic categories in fossil hominids. Cold Spring Harbor Symp. Quant. Biol. 15:109-118.

Hailc-Selassie, J. 2001. Late Miocene hominids from the Middle Awash, Ethiopia. Nature 412: 178-180. Hcbcrcr, G. 1963. Ubcr cincn neuen archanthropicn Typus aus dcr Oldoway-Schlucht. Z. Morph.Anthropoi 53:171-177. Hill, A. et al. 1992. Earliest Homo. Nature 355: 7 1 9 - 7 2 2 . Howell, F. C. 1978. Hominidae. In: V. Maglio and H . B. S. Cooke (cds.), Evolution of African Mammals. Cambridge, M A : Harvard University Press, pp. 1 5 4 - 2 4 8 . Hublin, J. J. 2001. Northwestern African Middle Pleistocene hominids and their bearing on the emergence of Homo sapiens. In: L. Barham and K. Robson-Brown (eds.), Hitman Roots: Africa and Asia in the Middle Pleistocene. Bristol, UK: Western Academic and Specialist Press, pp. 9 9 - 1 3 1 . Hughes, A. R. and P. V. Tobias. 1977. A skull probably of the genus Homo from Stcrkfontein, Transvaal. Nature 265: 310-312. Huxley, T. H. 1863. Zoological Evidences as to Mans Place in Nature. London: Williams and Norgate. International Commission on Zoological Nomenclature. 1999. International Code of Zoological Nomenclature. London: The Natural History Museum. Kimbel, W . et al. 1996. Late Pliocene Homo and Oldowan tools from the Hadar Formation (Kada Hadar Member), Ethiopia./ Hum. Evol. 31: 5 4 9 - 5 6 1 . Klein, R. 2000. The Human Career: Human Biological and Cultural Origins, 2nd ed. Chicago: University of Chicago Press.

Mayr, E. 1964. 1963. The taxonomic evaluation of fossil hominids. In: S. L. Washburn (ed.), Classification and Human Evolution. New York: Wenncr-Grcn Foundation, pp. 3 3 2 - 3 4 6 . Reno, P. L. ct al. 2003. Sexual dimorphism in Australopithecus afarensis was similar to that of modern humans. Proc. Natl Acad. Sci (USA) 100: 9404-9409. Rightmire, G. P. 1990. The Evolution of Homo erectus: Comparative Anatomical Studies of an Extinct Human Species. Cambridge, UK: Cambridge University Press. Schoetensack, O. 1908. Der Unterkiefer des Homo hcidelbergensis aus den Sanden von Mauer bei Heidelberg. Leipzig: W . Engelmann. Schrenk, F. et al. 1993. Oldest Homo and Pliocene biogeography of the Malawi Rift. Nature 365: 833-836. Schwartz, J. H . 1998. Lufengpithecus and hominoid phylogcny: problems in delineating and evaluating phylogenetically relevant characters. In: D . Begun, C. V. Ward and M . D. Rose (eds.), Function, Phylogeny and Fossils: Miocene Hominoid Evolution and Adaptations. New York: Plenum Press, pp. 3 6 3 - 3 8 8 . Schwartz, J. 2000. Taxonomy of the Dmanisi crania. Nature 289:55. Schwartz, J. H . 2004a. Barking up the wrong ape-australopiths and the quest for chimpanzee characters in fossil hominids. Coll.Antropol. 28 (suppl. 2):S7-101. Schwartz, J. H . 2004b. Getting to know Homo erectus. Science 305:53-54.

Kuman, K. and R. J. Clarke. 2000. Stratigraphy, artefact industries and hominid associations for Stcrkfontein, Member 5 . / . Hum. Evol. 38: 8 2 7 - 8 4 7 .

Schwartz, J. H . and I. TattcrsaU. 1996a. Toward distinguishing Homo neanderthalensis from Homo sapiens, and vice versa. Anthropologic (Brno) 34 (1): 7 9 - 8 8 .

Leakey, L. S. B., P. V. Tobias and J. R. Napier. 1964. A new species of the genus Homo from Olduvai Gorge, Tanzania. Nature 202: 3 0 8 - 3 1 2 .

Schwartz, J. H . and I. TattcrsaU. 1996b. Whose teeth? Afr/wr
Leakey, M . G. et al. 2001. New hominin genus from eastern Africa shows diverse middle Pliocene lineages. Nature 410:433-440. - Linnaeus, C.^ 1735. Sysiema Naturae, Yx ed. Stockholm: * • Kicscwettcn '' "C

Schwartz, J. H . and I. TattcrsaU. 2000a. W h a t constitutes Homo erectus* Acta Anthropol. Sinica, 19 (Suppl.)21-25. Schwartz, J. H . and I. TattcrsaU. 2000b. The human chin revisited: W h a t is it and who has it? / . Hum. Evol. 3S: 367-409.

H o M I N U ) C KAN I OMENTAL M O K I'll O LO(J IK S : A N O v E K V I E W

Schwartz, J. I. ;U1d L Tattcrsall. In press. Morphology, variS> StCmatics

In:

• %oo ' ' J- Radovcic (cd.), Kraptna 1899-1999: Krapina Neandertah and Human Evolution tn Central Europe. Zagreb: II ravatski Prirodoslovni Muzej. Senut, B. and M. Pickford. 2001. First hominid from the Miocene (Lukeino Formation, Kenya). C. R. Acad. Sci Pans/Set. Terre Planetes 332: 137-144. Stringer, C. B. and R. McKie. 1996. African Exodus: The Origins of Modern Humanity. New York: Henry Molt. Stringer, C. B., J.-J. Hublin and B. Vandermecrsch. 1984. The origin of anatomically modern humans in western Europe. In: F. Smith and F. Spencer (eds.), The Origins of Modern Humans: A World Survey of the Fossil Evidence. New York: Alan R. Liss, pp. 51-135. Tattcrsall, I. 1986. Species recognition in human paleontology./. Hum. Evol. 15:165-175. Tattcrsall, I. 1995. The Fossil Trail: How We Know What We Think We Know About Human Evolution. New York: Oxford University Press.

513

Turner, C. G. 1984. Advances in the dental search for Native American origins. Acta Anthropol. 8: 23-78. Vekua, A. ct al. 2002. A new skull of early Homo from Dmanisi, Georgia. Science 297: 85-89. Wcidcnrcich, F. 1943. The skull of Sinanthropus pekinensis: a comparative study on a primitive hominid skull. Palaeontol. Sin. Ser. D: 1-291. White, T. D., G. Suwa and B. Asfaw. 1994. Australopithecus ramidtiSy a new species of early hominid from Aramis, Ethiopia. Nature 371: 306-312. White, T. D., G. Suwa and B. Asfaw. 1995. Corrigendum to: Australopithecus ramidust a new species of early hominid from Aramis, Ethiopia. Nature 375: 88. White, T. D. ct al. 2000. Jaws and teeth of Australopithecus afarensis from Maka, Middle Awash, Ethiopia. Am. J. Phys. Anthropol. 111:45 - 68.

Tattcrsall, I. 1997. Out of Africa again . . . and again? Sci Am. 276 (4): 4 6 - 5 3 .

Wildman, D. ct al. 2003. The role of natural selection in shaping 99.4% identity between humans and chimpanzees at nonsynonymous DNA sites: implications for the genus Homo. Proc. Natl. Acad. Sci (USA) 100: 7181-7188.

Tattersall, I. 2000. Once we were not alone. Sci Amer. 282 (1): 5 6 - 6 2 .

Wolpoff, M . 2000. Paleoanthropology, 2nd ed. Boston and New York: McGraw-Hill.

Tattersall, I. and N. Eldredge. 1977. Fact, theory and fantasy in human paleontology..^///. Sci. 65:204-211.

Wood, B. 1991. Koobi Fora Research Project, Vol. 4: Cranial Remains. Oxford: Clarendon Press.

Tattersall, I. and J. H . Schwartz. 2000. Extinct Humans. Boulder, C O : Westview Press.

Wood, B. 1992. Early hominid species and speciation.

Tobias, P. V. 1991. Olduvai Gorge, Vol. 4: The Skulls, Endocasts and Teeth of Homo habilis. Cambridge, UK: Cambridge University Press.

/ Hum. Evol. 22:351-365. Wood, B. and M. Collard. 1999. The changing face of genus Homo. Evol. Anthropol. 8:195-207.

tzhm Hntionnl d'l!isto!re Nait

514

H O M I N I D CRANIODENTAL M O R P I I O L O O I E S : AN

OVERVIB

w

Plate 1. Lower dentitions. L to R: Olduvai Gorge O H 7; Ravin de Pluie Ouranopithecus RPL 54 and 55. Not to scale.

Plate 2. Lower M3s of (L to R): CMK BAR lOOO'OOa, Omo L628-3, and Omo L795-1 (scale = 1 cm).

HOMINID CRANIODENTAL M O R P H O L O G I E S : A N OVERVIEW

515

: Makapansgat MLD 6; Bottor Plate 3. Upper teeth. Top L: Taung j Top | j Kromdraai TM 1517a; Bottom Sterkfontein StW 252 (scale = 1 cm).

516

H O M I N I D GRANIODENTAL M O R P H O L O G I E S : AN OVERVIEW

I?late 4. Facial views. L column, top to bottom: Taung 1; Makapanagat MID 6; Stcrkfontein Sts 5; Stcrkfontcin StW 505. (05. K R column, top to bottom: Stcrkfontein StW 183a; Kromdraai TM 1517a; Stcrkfontcin Sts 52a; Stcrkfontcin Sts 71 (Not to scale).

HOM.N.D C R A N , O D E N T A L

M O R P „ O L O G I E S : AN O V . R V . B W

517

, T w LtoR-SterkfontcmSts5;Makapan S gatMLD37/38.Middlc l0 w Plate 5. Inferior views of crania and petrosals. P?° ' D N H 7 ( s c a i e = 1 cm), row, L to R: Sterkfontein St. 19, Stw 53g. Bottom: Dnmolen DN

518

HOMINID

GRANIODENTAL MORPHOLOGIES:

AN

OVERVIEW

Plate 6. Upper teeth. Top L: Drimolen D N H 7; R: Sterkfontein StW 53a. Middle L: Swartkrans SK 48, R: Olduva O H 5. Bottom L: West Turkana KNM-WT 17400; R: Chesowanja KNM-CH 1 (Not to scale).

HOMDWDID)

CBLAsriiiD>E3inrAiL

MORPHOLOGIES:

Ax

OVERVIEW

519

Plate 7. Upper teeth. Top L: Swartkrans SK 55a; Top R: Kromdraai KB 5222; Bottom: Sterkfontein Sts 24a (scale lcm).

520

HOMINID CllANIODENTAL M o RPII OLOG I ES :

AN

O V E R V I EW E

Plate 8. Lower teeth. Top L: Taung 1; R: Swartkrans SK 64. Middle L: Kromdraai KB 5503; R: Swartkrans SK 3978. Bottom L: Swartkrans SK 61; R: Kromdraai T M 1604 (scale = 1 cm).

H O M I N I D GRANIODENTAL M O R P H O L O G I E S : AN OVERVIEW

52f

Plate 9. Lower teeth. L to R: Swartkrans SKW 5; Makapansgat MLD 18; KromdraaiTM 1517b (scale = 1 cm).

1 Plate 10. Lower tee

L: Sterkfontein StW 404; R: Makapansgat MLD 2 (acale - 1 cm).

522

HOMINID

CRANIODENTAL MORPHOLOGIES:

AN

OVERVIEW

Plate 11. Lower teeth. Top L: Swartkrans SK 55b; R: Kromdraai T M 1536. Bottom L: Swartkrans SKx 4446; R: Sterkfontein StW 278 (scale = 1 cm).

HOMINID GRANIODBNTAL M O R P H O L O G I E S : AN

OVERVIEW

523

k

Plate 12. Upper molars. Top L: Sterkfontein StW 277; R: Hadar AL 333x-l. Bottom L: Omo L50-2; R: Kanapoi KNM-KP 34725G (scale = 1 cm).

524

H O M I N I D C R A N I O CENTAL M O R P H O L O G I E S : A N

OVERVIE

Plate 13. Swartkrans lower teeth. Top L: SK 15; Top R: SK 23; Bottom L: SKW 5; Bottom R: SK 25 (Not to scale).

H O M . N . D GRAN.ODENTAL M O R P H O L O G I E S : AN O V H N M I W

^^mm^^^^ Plate 14. Front views ux »—.—r -r VMMSwartkrans SK 48; Middle R: Koobi Fora KNM Koobi Fora KNM-ER 732 (scale = 1 cm)

..

r

525

VWM i u 23000; Middlo L:

526

HOMIKID CRAKIOOENTAL MORPHOLOGIES: AN

OVERVIEW

Plate 15. Lower teeth. Top L: Koobi Fora KNM-ER 1820; R: Koobi Fora KNM-ER 15930. Middle L: Omo L7-A125; R: Koobi Fora KNM-ER 729a; Bottom L: Koobi Fora KNM-ER 3230; R: Peninj 1 (Not to scale).

H O M I N I D C R A N I O D E N T A L M O R P H O L O G I E S : A N OVERVIEW

527

Plate 16. Lower teeth. Top L: Kanapoi KNM-KP 29281; Top R: Kanapoi KNM-KP 29287A; Middle L: Kanapoi KNMKP 30500F; Middle R: Kanapoi KNM-KP 29286F, G and C; Bottom: AUia Bay KNM-ER 20432A (scale - 1 cm).

528

HOMINID CRANIODENTAL MORPHOLOGIES: AN

OVERVIEW

Plate 17. Lower teeth. L column, top to bottom: Laetoli LH4; Kanapoi KNM-KP 30502D (L) and 30502E (R); Allia Bay KNM-ER 20422 (L) and 30201 (R); Melka Konture MK81 GAR IV 2 (insert not to scale). R column, top to bottom: Kanapoi KNM-KP 29286F and G (top) and 29286C (bottom); Kanapoi KNM-KP 31712T; Melka Konture MK81 GAR IV 2 (Not to scale).

HOMIXID CRAXIODENTAL M O R P H O L O G I E S : AX

OVERVIEW

Plate 18. Lower teeth. Top L: Laetoli LH4; Top R: Laetoli LH2; Bottom: Kanapoi C (bottom) (scale = 1 cm).

529

KNM-KP 29286 F, G (top) and

530

FIOMIKID CRANIODENTAL M O R P H O L O G I E S : AN OVERVIEW

Plate 19. Upper teeth. Top L: Laetoli LH21a; Top R: Olduvai OH 6; Bottom L: Laetoli LH3h; Bottom R: LH6e (scale = 1 cm).

HOMINID CRANIODRNTAL MORPIIOUOQIRR: AN OVBRV IRW

^^""^^^~" Plate 20. Lower teeth. Top I Hadar AL 200-lb; Bottom L:

531

, * ift Mi i 11 idflr AL 333w-l«s Middle Ki

532

HOMINID CRANIODENTAL M O R P H O L O G I E S : A N

OVERVIEW

H - ' " ; , ! ^ 1 ««*• Jop L: HadarAL 400-la;Top R: HadarAL 277-1; Middle L: Laetoli LH4; Middle R: Hadar AL 417-lb; Bottom L: Swartkrans SK 24; Bottom R: Sterkfontein Sts 52b (scale = 1 cm).

H^MJftlP CfcAWIOtfEtfTAlL Mo»lPBff<0> ILOlSll H5SH Aft 0VEKVIIEW

533

Plate 22. Upper teeth. Top L: Hadar AL 200-la; R: Laetoli LH 3h; Middle L: Laetoli LH21a; R: Hadar AL 666-1. Bottom: Hadar AL 333x-l (scale = 1 cm).

534

HOMINID

CRANIODENTAL MORPHOLOGIES: AN

OVERVIEW

Plate 23. Lower teeth. Top L: Maka MAK VP 1/12; R: Hadar AL 288-1. Bottom L: Hadar AL 400-la; R: Fejej FJ 7A-58-2 (top) and Maka MAK VP 1/4 (bottom) (scale = 1 cm).

HOMIXID GRANIODENTAL MORPHOLOGIES: AN

Plate 24. Belohdelie frontal compared in frontal and lateral views to the i (Not to scale).

OVERVIEW

535

536

HoMt&tf? G&AttwtHbttfAt, MFM(yfX'tm&&$ Ax Orfcima-tr

Plate 25. Rear view )f Chemcron temporal bone (KNM-BC 1) compared to the cranium KNM-WT 17000 (scale * 1 cm).

HOMINID G RAXIODENTAiL M'ORPHOI/OGSES: A s O v E K V J E W

Plate 26. Inferior views o f c r a n i a -J°P ^ " f i l S (scale = 1 cm) KNM-WT 15000; R: Koobi Fora KNM-ER1813 (scale

537

538

HOMINID GRANIODENTAL M O R P H O L O G I E S : AN

OVERVIEW

Plate 27. Lower teeth. Top L: Uraha UR 501; R: Koobi Fora KNM-ER 1802. (scale == 1 cm).

HOMINID GRANIODENTAL M O R P H O L O G I E S : AN

OVERVIE

w

539

^ ^ ^ T • -1 1 • R- Sanziran 2. Second row L: Sangiran | Plate 28. Lateral views of cranial specimens from Java. T o p m w ^ T n n d | | ^ ^ | i 3. Bottom row L: Ngandong fc N g a n d o n g 1 4 ( s c a e iriate zo. Lateral vicw& UJ. uaiu«u ~r R: Sangiran 17. Third row L: Ngawi; | Sambungmacan SM 1 cm).

540

He>MiN!D

CRANIODENTAL MORPHOLOQIBS: AN

OVERVIEW

row L. Ngaw,, ft Sambungmacan SM 3. Bottom n,w L: Ngandong 7; ft Ngandong 14 ( N o T ^ ) .

HoMIXID

CRANIODENTAL MORPHOLOGIES! A N OVERVIEW

T J ^ ^ ^ ^ T ^ S ^ Z T L ,

541

S27; * S7-3.1—. S7-73fc*- i -*

542

HOMINID

CRANIODENTAL

MORPHOLOGIES:

AN

OVERVIEW

Plate 31. Partial mandibles from Sangiran.Top L: Sib; R: S22. Middle L: S5; R: S6. Bottom: S9 (Not to scale).

HoMiNiD CRANIODENTAL MORPHOLOGIES: AN

OVERVIEW

543

•

»**%

m

Plate 32. Max, Sangiran S17 (scale = 1 cm).

ZKD Skull XL Top * R side of Sangiran I

Bottotn: R side of

544

H O M I N I D C R A N I O DENTAL M O R P H O L O G I E S : A N O V E R V I E W

Plate 33. Lateral views of crania. L column, top to bottom: Sangiran S17; Koobi Fora KNM-ER 3733; Koobi Fora KNM-ER 3732; West Turkana KNM-WT 15000; Dmanisi D2282. R column, top to bottom: Zhoukoudian cranial reconstruction (Sawyer and Tattersall version); Koobi Fora KNM-ER 3883; Olduvai OH9; Koobi Fora KNM-ER 1813 (scale = 1 cm).

HOMINID GRANIODENTAL M o R P H O i n p , ^ . "iURfHOLOGiEs:

A „ p> AN

OVERVIEW

545

FR 992- R' Koobi Fora KNM-ER 3734. Middle L: Olduvai Plate 34. Mandibles. Top L: L side of Koobi F < * ^ T * £ L s [ d e of Dmanisi D211 (scale = 1 cm). OH22; fc L side ofWestTurkana KNM-WT 15000. Bottom. L m M

546

H O M I N I D C R A N I O D E N T A L M O R P H O L O G I E S : AN OVERVIEW

Plate 35. Upper teeth. Top L: West Turkana KNM-WT 15000; R: Koobi Fora KNM-ER 1813. Bottom L: Olduvai OH13; R: Dmanisi D 2282 (not to scale).

H O M I N I D GRANIODENTAL M O R P H O L O G I E S : AN OVERVIEW

Plate 36. Partial

mandibles. L: Tighenif 2. R: Atapuerca Gnm Dolina ATD6-5 (Not to scale).

547

548

HoMtKiD G R A N I O D B N T A L M O R P H O L O G I E S : A N O V E R V I E W

Plate 37. Mandibles. L: Mauer jaw; R: Arago 13 (Not to scale).

HOMINID CRANIODENTAL M O R P H O L O G I E S : AN OVERVIEW

549

Plate 38. Lateral views of crania. Top L: Petralona; Top R: Bodo; Middle L: Arago 21; Middle R: Kabwe; Bottom L: Jinniushan; Bottom R: Dali (scale = 1 cm).

550

HOMINID CRANIODENTAL M O R P H O L O G I E S : AN

OVERVIEW

Plate 39. Front views of crania. Top L: Narmada; R: Maba. Bottom: La Chapelle-aux-Saints 1 (scale -= 1 cm).

HOMINIU CRANIODENTAL M O R P H O L O G I E S : AN OVERVIEW

551

Plate 40. Front views of crania. Top L: Jebel Irhoud 1; Top R: Fish Hoek; Middle L: Boskop; Middle R: CfcfM. 6; Hot torn I Omo 2; Bottom R: Skhul 5 (scale SB 1 cm).

APPENDIX

ADDENDA TO VOLUME 2 An oversight resulted in the omission from Volume 2 of this series of the description of the Eyasi 1 partial cranium that should have appeared on page 64 of that work, and of the Sangiran 4 Homo erectus maxilla

APPENDIX

that should have appeared on page 486. Similarly, the illustrations of the Olduvai O H 30 and 37 specimens that should have followed page 231 were omitted, as was the entire "Kapthurin" entry. These omissions are rectified on the following pages.

Figure 1. Kapthurin KNM-BK 67 (scales - 1 cm).

552

APPENDIX

APPENDIX

Figure 1.

553

(Continued).

554

APPENDIX

EYASI MORPHOLOGY Eyasi 1. Very incomplete and heavily reconstructed partial neurocranium, with variably large expanses in plaster. More of the L side is preserved than the R. Face is entirely missing, but it would originally not have been very large. Preserved are parts of the R supraorbital region, the R zygomatic process of the frontal, the glabellar region and apparent frontal above, the R and especially the L parietals, the L pctromastoid, and part of the L region of the foramen magnum and the bone lateral to it. Not all pieces are accurately placed, so that the small segment of bone bearing the sagittal suture is askew; the R zygomatic process of the frontal is positioned in the supraorbital region with the zygomaticofrontal suture oriented laterally; a piece of L parietal with a section of squamosal suture is too high and oriented forward; and, on the L, a portion of cranium bearing what appears to be part of a transverse sinus lies below the position of the preserved portion of the sigmoid sinus. The crosssection of parietal bone shows thick inner and outer tables and little diploic layer. Preserved bone presents marked porotic hyperostosis.

As reconstructed, especially in L profile, the skull would have been relatively long and moderately low. The smooth moderate curve up from the glabellar region is questionable; more reasonable seems to be the gentle curve down from the apparent midpoint of the sagittal suture to lambda and the more vertical profile of the relatively tall occipital plane. As reconstructed, the nuchal plane would have been long and quite horizontally oriented. Given the nature of the inferior portion of the preserved occipital, the nuchal plane did undercut the occipital plane. The reconstruction from the rear, if taken primarily from the more reliable L side, presents a moderately low, probably rather straight side wall that turned inward broadly with a long slope up to the midline; it seems likely that the greatest width had been rather low down. Seen from above, the skull was definitely not as rounded as reconstructed, but the occipital is broadly concave. What is preserved of the glabellar region and the apparently associated part of the R supraorbital region shows a distinct, horizontally oriented "corner"

between the flat anterior supraorbital surface and the shallow posttoral sulcus behind. As seen on the R, plaster fills much of the space of a frontal sinus that did not extend significantly up into the frontal or reach laterally to the midpoint of the orbit. As partially preserved on the R, the orbital roof was concave and formed a blunt angle with the anterior supraorbital surface. On the L, reasonably positioned pieces of parietal show marked temporal muscle scars moderately high up on the side of the skull before they arc down and back toward the lambdoid suture and then turn strongly forward and somewhat down toward the missing region of asterion. The occipital itself is quite broad (it is broadest biasterionically) and moderately tall s/i. The lambdoid suture is neither deeply interdigitated nor segmented; it coursed broadly around the region of lambda. The midline region just above the rounded angle between the occipital and nuchal planes (i.e. a very low superior nuchal line) is damaged for some of its extent but originally it may have had a somewhat flat, lozenge-shaped configuration. Basicranially, the foramen magnum was ovoid and very long. As seen on the L, flattish and probably not very large occipital condyles were placed well forward on its rim. The postcondylar fossa is remodeled and filled in. Preserved more laterally are two relatively parallel structures that appear to represent a stout Waldeyer s crest medially and, laterally, an occipitomastoid or paramastoid crest. Immediately lateral to the latter is a somewhat laterally compressed mastoid process with a downwardly rounded apex that had probably not extended much below the plane of the skull base. From the side this region is not in proper alignment and has attached to it superiorly a fragment of bone that bears no resemblance to a piece of squamosal. Anterior to this region lies the petrosal, which is somewhat damaged inferiorly and anteriorly. Basicranially it appears that part of a low, blunt vaginal process is preserved, and that it peaked slightly around a relatively large, rather medially placed styloid pit. A large (stylomastoid?) foramen lies well behind and slightly lateral to the styloid pit. Internally is a preserved portion of what would have been a long, stout frontal crest. The preserved R transverse sinus is quite tall, long, and deeply excavated. A relatively deep impression for the R occipital lobe lies above it. The depression for the L occipital lobe is shallower, but was probably larger overall. A fragment of bone bearing a deep sulcus

A I'l' EN I) IX

:>ro lies in plaster behind and below the petrosal; the sulcus appears to be a transverse sinus that is too interiorly placed. The preserved body of the petrosal itself bears a somewhat pronounced arcuate eminence and a superior petrous sinus. The subarcuatc fossa is somewhat patent (i.e. not closed off). The internal acoustic meatus is of moderate size. There is no evidence of a sub-subarcuatc fossa. Not too far behind the region of the subarcuatc fossa is a vertically oriented, downwardly curving sulcus of some depth that is bounded posteriorly by a raised, tube-like structure (a canal for a vessel or nerve?) that opens infcriorly through a foramen. This feature is bounded posteriorly by a relatively wide sulcus in which lies (almost level with the foramen of the aforementioned tube or canal) a small foramen from which emanates a groove that courses anteriorly and fades out along the side of the tube. Whichever of the vertical grooves is the true or primary sigmoid sinus, this is an unusual pattern for this region.

SANGIRAN MORPIIOLOGY Sangiran 4. L and R maxillary halves. The inferior margin of the apparently rather narrow nasal aperture is preserved. The lateral crest did not continue to the apparently blunt, not very protruding single nasal spine; instead, it faded out on the face just below the infcrolatcral corner of the nasal aperture. There is a blunt corner between the anteriorly sloping nasoalvcolar clivus and the raised, smooth, and short anterior floor of the nasal cavity; behind is a short and gradual slope down to the horizontal posterior part of the nasal floor. Incisive fossae arc large. O n both sides, the large maxillary sinus extends quite far forward, almost to the rim of the nasal aperture; it appears to have expanded medially into the region of the palate (corresponding to the area defined by the deep palate s steep walls). O n the R, the inferior anterior root of the zygomatic arch is visible; it lies level with the M l , and begins flaring laterally quite close to the alveolar margin. Internally, this region is filled out by the maxillary sinus. There is some damage on the L but it is clear that the subnasa region was broad and gently arced across, although in the

midline a slight ridge descends from the anterior nasal spine. The palate is long and very deep; its anterior slope is long, and its side walls arc quite vertical posteriorly. Tooth rows arc straight, and diverge fairly ly markedly posteriorly. The incisive foramen begins fairly far back along the palate; it opens as a deep groove anteriorly that splits into two shallow, divergent channels. On the L a deep notch is formed anterior to the missing region of the greater palatine foramen, between the wall of the palate and a large rugosity lateral to the midline. Teeth. II alveoli stout, not very long; 12 alveoli not much smaller or shorter. On both sides is a moderately sized diastema between the 12 alveolus and the rather large-crowned C. C is very wide b/1 at its base; buccal and lingual sides converge steeply toward the apex; the mesial slope is very short compared to the long distal slope. Overall, the lingual surface of C is convex, and bears a pair of low pillars and distinct margocristae; all structures are separated by thin vertical grooves. Even though there is considerable wear, it is unlikely that the surfaces of the cheek teeth ever showed much relief. PI is wider b/1 than P2 (primarily because the crown bulges buccally towards the neck). Both Pis are somewhat worn; yet it is obvious that the paracone lay just distal to the middle of the tooth, slightly behind the protoconc (thus, the mesial edge is longer than the distal edge). Occlusally this produces a broad angle between the PI and C. In P I , the space between paracone and protoconc forms a very shallow notch. The P2 paracone and protoconc lie essentially opposite one another in the middle of the crown; the groove between them is even shallower than in PI. Anterior and more centrally placed posterior thin grooves run along the bases of the cusps. All Ps have an m/d long metaconulc. M2 is bigger in all dimensions than M l . M J is almost as wide b/1 as M2, but is shorter m/d than is M l On all Ms the enamel is thinly cumulated, and all sides arc bulbous (the lingual side most so). In M l - 2 a thick postcingulum arcs distally out from the mate on the side of the mctaconc. hypoconc to term The lingual cusps arc subequal in size, as arc the more compressed buccal cusps. Trigon and talon basms re shallow and poorly developed. On M3 a rtucU postcingulum runs from the d/1 corner of the too 1 to STc side of the mctaconc, which is shghtly smaller the si than the paracone

i v r i' I. ,\ I) I X

KAPTHURIN LOCATION Collecting area to the west of Lake Baringo, northern Kenya, straddling the Knpthurin River and about 1.5 km west of the Marigat-Nginyang road (Map 2).

DISCOVERY A temporal fragment and a mandible (KNM-BK 67) were discovered in February 1966 by E. Kandini; a second mandible (BK 8518) was found by John Kimengich in 1982. MATERIAL Two fairly complete mandibles (KNM-BK 67 and 8518) with worn dentitions, an upper LI2 with broken root (BK 14297), a right ulna lacking the distal end, a right first metatarsal, and two manual first phalanges. Also two cranial fragments of uncertain stratigraphic association. An isolated but much older molar from the Ngorora Fm (BN 1378) is also included in the same collection.

DATING AND STRATIGRAPHIC CONTEXT The two Kapthurin mandibles were recovered from localities within the Middle Silts and Gravels Member of the Kapthurin Fm (M. Leakey et al., 1969; Tallon, 1978; Wood and Van Noten, 1986). Though some distance apart, both localities lie stratigraphically closely subjacent to the geochemically distinctive "Grey Tuff* and are thus reckoned to be roucrhly contemporaneous (Wood and Van Noten, 1986). Deino and McBrearty (2002) have recently Ar/Ar dated anothoclase from the Grey Tuff, and have bracketed the age of the fossils between 0.510 and 0.512 Ma. The isolated tooth from the Ngorora Fm, KNM-BN 1378, is much older, minimally 8.5 Ma (Hill, 2002).

ARCHAEOLOGICAL CONTEXT The sediments which yielded the BK 67 mandible also produced lava flakes and a heavy bifacially-flaked "pick." No handaxes of the kind that are found higher in the Kapthurin section were recovered at the hominid site.

PREVIOUS DESCRIPTIONS AND ANALYSES M. Leakey ct al. (1969) compared the BK 67 jaw closely to the "Atlanthropus" mandibles from Tighcnif, and concluded that it represented a species of Homo, probably but not certainly Homo erectus. Wood and Van Noten revisited this material in their description of the BK 8518 specimen, and after making a wide range of comparisons came up with the conclusion that both mandibles represented the same species o(flomoy for which they preferred the designation Homo sf>. indet. (aff. erectus). Deino and McBrearty (2002) raised the possibility that the mandibles should be assigned to Homo rbodesiensis, although this suggestion seems to have been made on the basis of their dating rather than on any appraisal of morphology. The Ngorora molar BN 1378 was said by Bishop and Chapman (1970) to be a hominid resembling Kcnyapithecus but showing "characters suggestive of an evolutionary trend towards both Homo and Australopithecus" (p. 917).

MORPHOLOGY The Kapthurin collection consists of two fairly complete mandibles, an LI2 with broken root, and two cranial fragments that may (or may not) be of similar stratigraphic provenance. Also various postcranials (a R ulna lacking the distal end, a R first metatarsal, and two manual first phalanges). The two mandibles are both reasonably attributed to the same rnorph. lhe much older isolated molar (KNM-BN 1378) from the Ngorora Fm is reminiscent of A. anamensxs. KAPTHURIN MORPH (INCLUDES KNM-BK

67AND8518A) KNM-BK 67. Fairly complete, though very weathered and somewhat reconstructed mandible with broken RP2 and RM1, and worn R and LM2 M3. The corpus is short s/i at the symphysis and deepens posteriorly. Viewed ^ / ^ ^ ^ the jaw has a very tight curve and the t o o t h * « minimally divergent. In profile, the symph) is d scends straight from the alveolar margin, w,th « t a « P backward curve inferiorly. The V ^ t ^ ^ steep and is undercut below by a tubercle-free genial p t of moderate size and depth. Immediately beb E L the bone thickens. Twin ^ ? ^ Z ' riorly directed digastric fossae he ^ ^ ^ ing.The symphyseal bone is much thicker b/1 than bone immediately behind, l h e R and L mental

A i» i» ]•: N n i

x

557 foramina are relatively large and lie below the P2s. Mylohyoid lines are not discernible. The submandibular fossae on both sides are long and reasonably impressed. The mandibular foramina arc s/i tall, very compressed, and posteriorly directed; they lie well above the level of the teeth. O n the R is preserved a stout but low lingula. As seen on the R, the anterior root of the ramus arises from somewhat below M2; it runs steeply upward, masking only the distal part of M 3 . A modest gutter lies between the ramus and M 3 (as seen on the R). On both sides, the bone in front of the mandibular foramen is thickened and flows into a stout internal alveolar crest. This crest may have continued fully up to the coronoid process. The preserved anterior part of the gonial region is fairly smooth externally (except for a ridge-like muscle scar inferiorly on the L). On both sides, a medial pterygoid tubercle is fairly well developed; it lies level with the mandibular foramen. On the R, another ridge lies below the primary tubercle. As seen on the R, the condyle is quite m/1 broad and flat across. The sigmoid notch crest terminates at the lateralmost extremity of the condyle. Teeth. Partial alveoli are present for the anterior teeth. Their roots were apparently not long; the C root was not very robust. Roots of P i s are present; the crown many have had a slight m/b orientation. The crown of P2 is broken and very worn; the protoconid and metaconid appear to have been low, subequal, and centrally placed. The P I crown is subcircular in occlusal outline. The RM1 is worn and partially broken; the crown was probably ovoid in outline with a centrally placed hypoconulid. The worn, ovoid M2s are longer. They apparently lacked trigonid basins and paracristids, but have relatively large, subequal, and opposite-lying protoconids and metaconids, smaller, subequal, and opposite-lying hypoconids and entoconids, large centrally placed hypoconulids that broadly straddle the midline of the tooth, and moderate hypoflexid notches. The quite worn M3s are slightly shorter m/d than the M2s. They are subovoid in outline, taper distally, and bear distinct metastylids (twinned on the L). As in the M2s, the M 3 hypoconulid bases broadly straddle the midline of crown. The subequal protoconids and metaconids are large and lie opposite each other. The hypoconids are larger than the entoconids because of the presence of metastvlids. T h e base of the hypoconid extends linruallv across the midline of the crown and mesial to the entoconid, to contact the base of the metaconid.

The hypoconulids are large and broadly straddle the midline of the tooth, but have more of a lingual ores

™TLtb}'

S h a U W but distinct

°

^hes.

KNM-BK8518A. A partial mandible with most or the corpora and part of the L ramus with the coronoid process. Preserved are the roots or worn and damaged crowns of all teeth. Also, there arc two isolated, very worn teeth. For the size of the mandible, the corpora arc thick b/1, but not very tall s/i. The corpus is shallowest at the symphysis; it deepens to the level of P2. Seen from above, the front of the jaw forms a tight curve, and the check tooth rows are mildly divergent, with noticeable flaring of the bone lateral to the Ms. In profile, the anterior surface of the symphysis curves sharply down and back to the inferior margin, where there is a slight rise in the midline. The postincisal plane is short and moderately steep; it terminates relatively high up above a large, deep genial pit. Below the pit the bone is thickened and bears two thin genial crests. Below the thickening the a/p long, moderately excavated digastric fossae point inferiorly and strongly posteriorly. On both sides, beginning under and close to M 3 , well defined mylohyoid lines slant anteriorly and down. Modest submandibular fossae lie anteriorly below them. As seen on both sides, the anterior root of the ramus takes origin at the level of, and somewhat below, the M2. On the R, the ramus curves up and forward into a tall, shallow submandibular notch. The anterior part of the gonial region is preserved on the L; it bears a small muscle scar inferiorly. The coronoid process is bluntly peaked; from it descends a thick pillar that probably curved down and around into the internal alveolar crest. On the L, the ramus masks the distal half of the M 3 , from which it is separated by a modest gutter. On each side, a somewhat small mental foramen, accompanied by accessor)' foramina, lies below P I . Teeth. The 11-12 roots arc compressed, with the 12 roots being somewhat larger than the smaller lis. Nothing can be said about the Cs. The RPl is extremely worn; its crown was quite expansive and had iliehtlv anteriorly oblique orientation to it; there a s ° J .. . . i 11.. TUOP? \c ronrowere possibly two roots buccally. The RP2 is reprc sented by two roots. Both M i s arc quite worn and damaged. As judged from the L, the M l was shorter m/d than the M2, which is rectangular with rounded corners. The quite worn M3s would have been the longest teeth m/d; they taper slightly distally. The

APPENDIX

Figure 2. Kapthurin KNM-BK 8518A (scales = 1 cm).

A l» l> i;

subcqual but nor very large protoconids and mctaconids lie opposite each other. As better seen on the L there is a fairly large metastylid. T h e base of the large hypoconid extends lingually across the midline of the crown and mesial to the small cntoconid to contact the base of the mctaconid. T h e large, apparently subdivided hypoconulids straddle the midline of the crown with more of a lingual extension. As better seen on the L, there is a groove between the cntoconid and hypoconulid that accentuates their adjacent borders. NGORORA

IMORPH

KNM-BN 1378. A L M 1 crown that is slightly worn with a good mesial protostylar pit and prccingulum. It is slightly d/1 swollen by the hypoconc and postcingulum. T h e cusps arc slightly compressed and almost peripheral. Among the hominids described in this volume the closest comparison appears to be with A. anamensis. Other (not illustrated) KNM-BK14297. A LI 2 , with a moderately compressed broken root. T h e crown is not greatly flaring but is reasonably shoveled, with raised lingual margins. T h e buccal surface curves down from the root.

559 REFERENCES Bishop, W. W. and G. R. Chapman. 1970. Early Pliocene sediments and fossils from the Northern Kenya Rift Valley. Nature 226: 914-918. Dcino, A. and S. McBrcarty. 2002.40Ar/ 39Ar dating of the Kapthurin Formation, Baringo, Kenya. Jour. Hum. Evol. 42:185-210. Hill, A. 2002. Palcoanthropological research in the Tugcn Hills, Kcnya./our. Hum. Evol. 42:1 -10. Leakey, M. et al. 1969. An Achculcan industry with a prepared core technique and the discovery of a contemporary hominid mandible at Lake Baringo, Kenya. Proc. Prchist. Soc. 35:48-76. Tallon, P. W. J. 1978. Geological setting of the hominid fossils and Achculcan artifacts from the Kapthurin Formation, Baringo District, Kenya. In: W. W. Bishop (cd.), Geological Background to Fossil Man. Edinburgh: Scottish Academic Press, pp. 361-373. Wood, B. A. and F. L. Van Notcn. 1986. Preliminary observations on the BK 8518 mandible from Baringo, Kenya. Amcr.Jour. Phys. Anthrop. 69:117-127. Repository National Museums of Kenya, P. O. Box 40658, Nairobi, Kenya.

560

APPENDIX

OLDUVAI GORGE

OLDUVAI

Figure 1. OH 30 (scales = 1 cm).

APPENDIX

OLDUVAI

tigure

561