THE ECOLOGICAL CONTEXT OF THE EARLY PLEISTOCENE HOMININ DISPERSAL TO ASIA by Robin Louise Teague A.B. in Anthropology, 2001, Harvard University A dissertation submitted to The Faculty of The Columbian College of Arts and Sciences of The George Washington University in partial fulfillment of the requirements for the degree of Doctor of Philosophy August 31, 2009 Dissertation directed by Richard Potts Curator of Physical Anthropology, National Museum of Natural History, Smithsonian Institution Alison S. Brooks Professor of Anthropology The Columbian College of Arts and Sciences of The George Washington University certifies that Robin Louise Teague has passed the Final Examination for the degree of Doctor of Philosophy as of June 16, 2009. This is the final and approved form of the dissertation. THE ECOLOGICAL CONTEXT OF THE EARLY PLEISTOCENE HOMININ DISPERSAL TO ASIA Robin Louise Teague Dissertation Research Committee: Richard Potts, Curator of Physical Anthropology, National Museum of Natural History, Smithsonian Institution, Dissertation Co-Director Alison S. Brooks, Professor of Anthropology, Co-Director Lars Werdelin, Senior Curator, Swedish Museum of Natural History, Committee Member ii © Copyright 2009 by Robin Louise Teague All rights reserved iii Acknowledgments I would like to acknowledge a number of people who have helped me and guided me through the process of writing my dissertation. First, I would like to thank my committee: Rick Potts, Alison Brooks, Lars Werdelin, Margaret Lewis and Brian Richmond. My advisor, Rick Potts, led me into a stimulating area of research and supported me in pursuing a large and ambitious project. He has encouraged me all through the time I have worked on this dissertation. Alison Brooks has helped me with enthusiasm, pointing out differing perspectives and opportunities. Lars Werdelin has been a source of detailed and helpful information and has always been available to answer questions and provide guidance. I am also grateful to Brian Richmond and Margaret Lewis for many helpful comments and for making time for my dissertation. I would also like to thank my family for their love and support during my time in graduate school and especially during the process of writing. Their encouragement was essential to my success. I would like to thank my fellow students at GWU for many years of friendship. I would like to thank that faculty of the Hominid Paleobiology Doctoral Program and the Department of Anthropology for their support. At the Smithsonian, I thank Jenny Clark, Briana Pobiner and Matt Tocheri for their assistance and for making me feel welcome. For access to mammalian skeletal collection, I thank Linda Gordon. I am also grateful to the Smithsonian Libraries for letting me check out and renew many books many times. iv Thanks go also to the many people who facilitated my access to fossils at the Kenya National Museum and the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, as well as many other museums. In particular, Wang Wei traveled with me, assisting with translation and helping me make the contacts necessary to study many of the fossil specimens in Chinese museums. I would also like to thank Gao Xing, Deng Tao, Qiu Zhanxiang, Qi Guoqin, Huang Weiwen, Hou Yamei, Zhu Rixiang, Deng Chenglong, Li Qing Kui and Wei Guangbao for helping me study fossil specimens while I was in China. For financial support, I would like to thank the IGERT program in Hominid Paleobiology at GWU as well as the Smithsonian National Museum of Natural History where I had a predoctoral fellowship. My years of study at GWU and at the Smithsonian Human Origins Program have been extremely rewarding. This dissertation research was funded by NSF Grant BSC 065092. v Abstract of Dissertation The Ecological Context of the Early Pleistocene Hominin Dispersal to Asia The ecological context of the first known dispersal of Homo into East Asia is investigated here using information from large mammals, and particularly from carnivores. The aims were to determine whether hominins occurred in similar ecological contexts compared with sites in East Africa, and whether carnivore guilds in East Asia and East Africa were similar in composition in terms of ecologically comparable species. To answer these questions, dental measurements were taken on large mammalian specimens from East Asian Plio-Pleistocene sites, including hominin and non-hominin sites, and from specimens found at Olduvai Gorge and Lake Turkana in East Africa. Dental measurements were taken to estimate body mass and hypsodonty, as well as ecomorphological characteristics in carnivores. Each large mammal species was classified as an ecotype, which is a combination of body mass, diet and substrate (i.e., terrestrial, arboreal and aquatic) characteristics. The ecotype analysis shows that East Asian and East African fossil sites were significantly different from each other in ecological structure, with the Asian sites having a greater concentration of browsers and mixed feeders, while East African sites had more grazers. The East Asian hominin sites included varied ecological structures, implying that hominins were not tied to a single type of environment on their initial dispersal. Carnivore ecomorphological indices related to body mass and feeding adaptations, such as the amount of the dentition devoted to slicing, grinding and bone-cracking. Carnivore guilds containing sets of species with similar feeding adaptations and body mass would have presented similar opportunities for vi scavenging and degrees of competition for hominins. The Hyaenidae differed between Africa and Asia in features related to fourth premolar size. Omnivorous ursids were present in Asia but not in Africa. In East Asia, there were also decreases in the number of species of Hyaenidae and Canidae from the Late Pliocene to the early Pleistocene. Despite this, the remaining Asian hyaenid, Pachycrocuta , would have been a formidable competitor for scavenging hominins. Overall, hominins occurred in varied ecological settings, and competed with a carnivore guild that had species with different adaptations compared with Africa. vii Table of Contents Acknowledgments……………………………………………………………………....iiv Abstract of Dissertation………………………………………………………………….vi Table of Contents…………………………………………………………………... ….viiii List of Figures…………………………………………………………………………....ix List of Tables……………………………………………………………………………xii Chapter 1: Introduction…………………………………………………………………..1 Chapter 2: Background to ecological similarity analysis……………………………….11 Chapter 3: Methods to determine ecological similarity………………………………....41 Chapter 4: Results of the ecological structure analysis………………………………....94 Chapter 5: Background to carnivore ecomorphology……………………………….....129 Chapter 6: Carnivore ecomorphology methods……………………………………......151 Chapter 7: Carnivore ecomorphology results……………………………………….....176 Chapter 8: Discussion……………………………………………………………….....236 Bibliography…………………………………………………………………………...270 Appendices………………………………………………………………………….....292 viii List of Figures Figure 2.1 Map of East Asian fossils……………………………………………………39 Figure 3.1 Modern Eurasian localities used for comparison………..…………………...52 Figure 3.2 Modern African localities used for comparison……………………………...53 Figure 4.1 Scatterplot of the CA of the modern faunal assemblages and ecotypes..........99 Figure 4.2 NMDS using Euclidean distance of modern divisions……………………..100 Figure 4.3 CA scatterplot of modern faunal sites excluding rainforests…………..…..102 Figure 4.4 NMDS of modern sites excluding rainforests……………………………...104 Figure 4.5 Scatterplot of a CA of the modern sites and ancient fossil assemblages…..109 Figure 4.6 Scatterplot of a CA of the modern and ancient assemblages, axes 2 and 3………………………………………………………………………………………..110 Figure 4.7 NMDS analysis of ancient and modern sites…………………………….....112 Figure 4.8 CA scatterplot of modern and ancient faunal assemblages, excluding modern rainforests………………………………………………………………………….…...115 Figure 4.9 CA scatterplot, axes 2 and 3: Modern sites (excluding rainforests) and ancient faunas………………………………………………………………………………......116 Figure 4.10 NMDS plot of Plio-Pleistocene assemblages with modern sites (excluding rainforests)…………………………………………………………………………......120 Figure 4.11 Correspondence analysis scatterplot of Plio-Pleistocene sites……………125 Figure 7.1 Scatterplot of the CA for Canidae category scores………………….……..180 Figure 7.2 Scatterplot of NMDS analysis of Hamming distances for Canidae………..181 ix Figure 7.3 PCA Scatterplot of Canidae index values from East Africa and East Asia…………………………………………………………………………………….182 Figure 7.4 Loadings for component 1 of the PCA of Canidae fossils……………........183 Figure 7.5 Loadings for component 2 of the PCA for Canidae fossils…………….......184 Figure 7.6 CA Scatterplot of Hyaenidae category scores………………………….......189 Figure 7.7 NMDS scatterplot of Hyaenidae Hamming distances…………………......190 Figure 7.8 PCA Scatterplot of Hyaenidae index values………………………….........191 Figure 7.9 Component 1 PCA loadings for Hyaenidae…………………………..........192 Figure 7.10 Component 2 PCA loadings for Hyaenidae………………………............193 Figure 7.11 CA Scatterplot of Felidae category scores…………………………...........201 Figure 7.12 NMDS scatterplot of Hamming distances for Felidae…………….……....202 Figure 7.13 PCA Scatterplot of Felidae index values…………………………….........203 Figure 7.14 PCA loadings for component 1 for Felidae………………………….........204 Figure 7.15 PCA loadings for component 2 for Felidae……………………….............205 Figure