THE HUNT FOR THE DAWN MONKEY University of California Press Berkeley and Los Angeles, California University of California Press, Ltd. London, England © 2004 by the Regents of the University of California Library of Congress Cataloging-in-Publication Data Beard, K. Chris. The hunt for the dawn monkey : unearthing the origins of monkeys, apes, and humans / Chris Beard; illustrations by Mark Klingler. p. cm. Includes bibliographical references and index. isbn 0–520–23369–7 (cloth : alk. paper) 1. Primates, Fossil. 2. Monkeys, Fossil. 3. Fossil hominids. 4. Human beings—Origin. 5. Paleoanthropology. I. Title. qe882.p7b35 2004 569'.8—dc22 2004001403 Manufactured in the United States of America 13 12 11 10 09 08 07 06 05 04 10987654 321 The paper used in this publication meets the minimum requirements of ansi/niso z39.48–1992 (r 1997) (Permanence of Paper). For Sandi Amor vitae supervivit The Hunt for the Dawn Monkey Unearthing the Origins of Monkeys, Apes, and Humans CHRIS BEARD ILLUSTRATIONS BY MARK KLINGLER UNIVERSITY OF CALIFORNIA PRESS Berkeley Los Angeles London Contents List of Illustrations / ix Preface / xiii 1 Missing Links and Dawn Monkeys / 1 2 Toward Egypt’s Sacred Bull / 29 3 A Gem from the Willwood / 61 4 The Forest in the Sahara / 87 5 Received Wisdom / 115 6 The Birth of a Ghost Lineage / 142 7 Initial Hints from Deep Time / 167 8 Ghost Busters / 194 9 Resurrecting the Ghost / 215 10 Into the African Melting Pot / 246 11 Paleoanthropology and Pithecophobia / 277 Notes / 295 References Cited / 313 Index / 331 Illustrations FIGURES 1. Cranial anatomy typical of prosimians and anthropoids 7 2. The author and Wen Chaohua 10 3. Barnum Brown’s expedition to Myanmar 17 4. Holotype lower jaw of Amphipithecus mogaungensis 19 5. Ladder and tree evolutionary paradigms 26 6. Georges Cuvier 31 7. Nineteenth-century exploitation of phosphatic fissure- fillings in France unearths Adapis and other primate fossils 37 8. Lower jaws of two European adapiforms 46 9. Skull of Tetonius homunculus 65 10. Trogolemur and Shoshonius incisor morphology 69 11. Fragmentary specimen of lower jaw of Teilhardina 73 12. Gradual evolution documented in Bighorn Basin omomyids 77 13. Jacob Wortman and other notable paleontologists near Sheep Creek, Wyoming, 1899 85 14. Holotype lower jaw of Apidium phiomense 91 15. Elwyn Simons and Tom Bown in the Fayum 98 16. Face of Aegyptopithecus zeuxis 101 ix x LIST OF ILLUSTRATIONS 17. Fossil Epipremnum fruits 106 18. Artist’s rendering of Arsinoitherium 109 19. William Diller Matthew 119 20. Philip D. Gingerich 127 21. Frederick S. Szalay 130 22. Four competing versions of the primate family tree 137 23. Carnegie Museum of Natural History field party, Wind River Basin, Wyoming 149 24. Variation in the anatomy of the primate tibiofibular joint 162 25. Cartoon depicting the rationale behind the ghost lineage of early anthropoids 164 26. Marc Godinot searching for fossil primates in France 169 27. Fossil site of Glib Zegdou, Algeria 170 28. Isolated teeth of the early anthropoids Biretia and Algeripithecus 171 29. Holotype lower jaw of Eosimias sinensis 188 30. Schematic drawings of the lower dentition of some fossil primates 192 31. Skull of Catopithecus compared with that of a living pygmy marmoset 210 32. J. G. Andersson 218 33. Schematic drawings of the holotype specimens of Oligopithecus savagei and Hoanghonius stehlini 224 34. Holotype lower jaw of Xanthorhysis tabrumi 228 35. The divergent skull morphology of a living tarsier and squirrel monkey, compared with the holotype specimen of Phenacopithecus krishtalkai 233 36. Complete lower dentition of Hoanghonius stehlini 237 37. Part of the complete lower dentition of Eosimias centennicus 240 38. Eosimiid, omomyid, and tarsier lower jaws 241 39. Elongation of the calcaneus in tarsier, baboon, Shoshonius, and eosimiid 244 40. Jean-Jacques Jaeger in the field in Myanmar 256 41. Virtually complete lower jaw of Siamopithecus eocaenus 258 42. P4s of Eosimias sinensis, Eosimias centennicus, Siamopithecus eocaenus, and Proteopithecus sylviae 261 43. Cartoon depicting the early dispersal of anthropoids from Asia to Africa 268 44. Schematic drawings showing similarities in upper and LIST OF ILLUSTRATIONS xi lower molar structure shared by adapiforms and omomyids and by Altiatlasius and Eosimias 271 45. A provisional primate family tree 275 46. Henry Fairfield Osborn, proponent of the “dawn man” theory of human origins 281 47. The “dawn man” theory of human origins 284 PLATES Plates follow page 112. 1. Tarsier 2. Skull of Adapis parisiensis 3. Artist’s rendering of Adapis parisiensis 4. Artist’s rendering of Notharctus venticolus 5. Skull of Necrolemur antiquus 6. Artist’s rendering of Necrolemur antiquus 7. Skull of Shoshonius compared with that of a living tarsier 8. Artist’s rendering of Shoshonius cooperi 9. The L-41 site in the Fayum region of Egypt 10. Shanghuang fissure-fillings 11. Prospecting for fossils at Locality 7 on the southern bank of the Yellow River in Henan Province, Yuanqu Basin, central China 12. Geographic distribution of various living and fossil primates in Eurasia and Africa 13. Map of Wyoming, showing the location of some of the key fossils, fossil sites, and other geographic features mentioned in the text 14. Artist’s rendering of Eosimias sinensis encountering a group of smaller eosimiid primates Preface The story of human evolution has been told many times before, and it will no doubt continue to be revised and updated as new fossils are dis- covered. My goal in writing this book has been to add a much-needed prologue to what is now a familiar tale. If the major outlines of human origins are settled, the search for anthropoid origins remains scientifically in its infancy. Great strides have been made over the past two centuries, but we remain fairly ignorant of such basic questions as when, where, how, and why our earliest anthropoid ancestors evolved. This appraisal is not meant as a critique. Ignorance is to science as economic opportu- nity is to capitalism. It is more rewarding to toil in earnest on an unset- tled issue than to tinker at the margins of a topic that is largely known. The story of anthropoid origins is fascinating precisely because so much of it remains in flux. At the same time, it is a story that has never been made available to a wide audience, one that extends beyond the narrow group of academic specialists who have devoted much of their profes- sional lives to solving its mysteries. Teamwork plays a vital role in paleontology, because scientific ad- vances in this field hinge on isolated discoveries that reach across vast swaths of space and time. Over the past decade or so, I have had the privilege of working with some of the finest and most accomplished pa- xiii xiv PREFACE leontologists in the world, in places that few ever get to visit. I have no doubt that I have learned more from my colleagues than vice versa. Throughout, we have been united by our mutual goal of illuminating the remote ancestry that we humans share with other anthropoid or “higher” primates. Paleontology is one of the few academic disciplines in which field ex- ploration remains a fundamental part of the quest to expand knowledge and understanding. This unique combination of the possibility for per- sonal adventure and intellectual fulfillment is what attracted me to pa- leontology in the first place. I hope that I am able to impart a fraction of what I have experienced and learned during these past few years in this book. My role in this story would not have been possible without the sup- port and cooperation of a large number of individuals and institutions. It gives me great pleasure to thank my colleagues at the Carnegie Mu- seum of Natural History, Mary Dawson and Luo Zhexi, who have often ventured into the field with me and who have served as frequent sound- ing boards for my ideas, while constantly providing me with their own unique expertise. Equally important have been a number of other col- leagues who have worked alongside me in the field in China: Dan Gebo, Marc Godinot, Wulf Gose, John Kappelman, Leonard Krishtalka, Ross MacPhee, Jay Norejko, Tim Ryan, and Alan Tabrum. I am also deeply indebted to my friends and colleagues at the Institute of Vertebrate Pa- leontology and Paleoanthropology in Beijing: Qi Tao, Wang Banyue, Li Chuankuei, Wang Yuanqing, Tong Yongsheng, Wang Jingwen, Huang Xueshi, and Guo Jianwei. For years, these world-class scholars and in- domitable scientists have welcomed my American colleagues and me into their country and into their homes. During our joint expeditions to var- ious parts of China, they have imparted their knowledge and persever- ance along with their unmatched organizational skills, without which none of the expeditions could ever have been launched. More important, they have extended a hand of friendship to me and many other wei guo ren that will always be cherished. I also want to thank some of the sci- entists who played such critical roles in my formal education and pro- fessional training, and who have enlightened and inspired me through the years, among them Rich Kay, Elwyn Simons, Ken Rose, Tom Bown, and Alan Walker. Fieldwork in distant locales can be expensive, and none of this research could have been conducted without the financial support of various in- stitutions, including the Carnegie Museum of Natural History, the PREFACE xv Leakey Foundation, the National Geographic Society, and the Physical Anthropology Program at the National Science Foundation. A fellow- ship from the John D. and Catherine T. MacArthur Foundation gave me the flexibility to take on this challenge. In writing the manuscript, I have benefited from the wisdom and in- sight of numerous friends and colleagues, including Mary Dawson, Dan Gebo, Bert Covert, Ken Rose, Jean-Jacques Jaeger, Marc Godinot, and Hans Sues.