A Comprehensive Analysis of Long Bone Curvature in Neanderthals and Modern Humans Using 3D morphometries Isabelle Elisabeth Peter Maria De Groote A thesis submitted to University College London in fulfillment of the requirements for the degree of Doctor of Philosophy. 2008 UMI Number: U592544 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. Dissertation Publishing UMI U592544 Published by ProQuest LLC 2013. Copyright in the Dissertation held by the Author. Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 I, Isabelle De Groote, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. ii Abstract Since their discovery Neanderthals were described as having a marked degree of anteroposterior curvature of the femoral shaft. Although initially believed to be pathological, subsequent discoveries of Neanderthal remains made femoral curvature as well as the lateral curvature of the radius to be considered derived Neanderthal features. Femoral curvature has previously been used in racial identification in modern humans but its functional significance is poorly understood. A recent study on Neanderthals and early modern humans found no differences in femoral curvature, but did not consider size-corrected curvature. Therefore, the objectives of this study were to 1) use 3D morphometric landmark and semi-landmark analysis to quantify bone curvature (femur, ulna, radius) in Neanderthals, Upper Palaeolithic and recent modern humans, 2) compare adult bone curvature between these populations, and 3) test hypotheses on the effects of climate, body size, and activity patterns on curvature. Comparisons between and within populations were made using geometric morphometries (3D landmarks) and standard multivariate methods. Comparative material involved all available Neanderthal and Upper Palaeolithic modern human femora, ulnae and radii, archaeological (Mesolithic, Neolithic, Medieval) and recent human populations representing a wide geographical and lifestyle range. The study found that there are significant differences in the anatomy of the femur, ulna and radius between Neanderthals and modern humans. Neanderthals have more curved femora and radii than modern humans. Early modem humans are most similar to recent modern humans in their anatomy. Recent modem human analyses indicate that femoral curvature and forearm curvature are responses to disparate influences. Femoral curvature is a good indicator of activity level and habitual loading of the lower limb. Curvature of the forearm is a consequence of cold adaptation and its purpose is to maintain biomechanical function of the forearm despite its foreshortening. In memory of Charlie. You knew my strengths, You knew my weaknesses, You were my mentor, You were my friend. Acknowledgements First and foremost I thank my supervisors, Dr. Charles Lockwood and Professor Leslie Aiello, who have been as much friends as mentors. I also thank Professor Simon Hillson for his valuable advice. I am grateful to all the people who provided access to the fossils examined for this thesis: I. Tattersal, G. Sawyer at the American Museum of Natural History New York; R. Kruzynski at the Natural History Museum, London; Y. Rak of the Sackler School of Medicine, Tel Aviv; P. Mennecier at the Musde de PHomme, Paris; J.-J. Cleyet-Merle at the National Museum of Prehistory, Les Eyzies; V. Merlin-Anglade at the Museum of Perigord, Periguex; M. Teschler- Nicola at the Natural History Museum, Vienna; P. Semal of Royal Belgian Institute of Natural Sciences, Brussels; W. Menghin at the Museum of Prehistory, Berlin; J. Svoboda of the Institute of Archaeology, Dolni Vestonice; M. Dockalova at the Moravian Museum, Brno; P. Velemmsky, National Museum Prague; J. Chistov at the Kunstkamera, Saint Petersburg; D. Pezh^msky, Moscow State University; M. Morgan at the Peabody Museum, Harvard University, Boston; D. Hunt at the National Museum of Natural History, Smithsonian Institute, Washington; P. Bennike at the Medical University, Copenhagen. I would like to thank Philip Mitteroecker and Philip Gunz for the use of their Mathematica functions and Katya Bulygina for her patience in sharing her geometric morphometries knowledge. At University College London (UCL) first thanks go to the Anthropology Department Staff for their support throughout my graduate career. I thank all my friends over the years at UCL who provided stimulating conversations, proof readings, much needed distractions and emotional support. I thank all my non-UCL friends and in particular the Buddens, the Hubbards and the Madaras for their support and for letting me be part of their families. Special thanks go to Ruth Brown who is the best “English mum” I could possibly have found. Finally, I thank my parents, Geertje and Alexander De Groote, for supporting me in the choices I make and for encouraging me to fulfil my potential. I also thank my sister, Sabine, for keeping me with both feet on the ground, and my brother, Bert, for his random chats. I dedicate this thesis to my grandfather, Edouard Van Hove, as without his words of wisdom and funding I would not have been able to embark on this PhD. This project was supported by the Graduate School, UCL; The Leakey Fund; The Ruggles-Gates Fund for Biological Anthropological Research; The Wenner-Gren Foundation for Anthropological Research; Synthesys; and the UCL Alumni. v Table of contents CHAPTER 1. Introduction ..................................................................................................................1 1.1. Purpose of the study ....................................................................................................................1 1.2. Long bone curvature .................................................................................................................. 4 1.3. Neanderthals and modern humans ...........................................................................................5 1.4. Layout of the thesis.................................................................................................................... 9 CHAPTER 2. History of research on long bone curvature...........................................................10 2.1. Fem ur.......................................................................................................................................... 10 2.1.1. Comparative anatomy of the femur ..................................................................................10 2.1.2. Intraspecific variation in femoral curvature .................................................................... 11 2.1.3. Biomechanics acting on femoral curvature .....................................................................15 2.2. Radius and ulna ......................................................................................................................... 18 2.2.1. Comparative anatomy of lower arm anatomy ................................................................ 18 2.2.2. Intraspecific variation in the radius and ulna .................................................................20 2.2.3. Biomechanics acting on lower arm curvature ................................................................23 2.3. Possible causes for variation in long bone curvature ..........................................................25 2.3.1. Neanderthals and rickets ...................................................................................................25 2.3.2. Biomechanics and bone remodelling .............................................................................. 26 2.3.3. Body size ..............................................................................................................................31 2.3.4. Activity levels .................................................................................................................... 31 2.3.5. Climate.................................................................................... 33 2.4. Hypotheses and predictions ....................................................................................................35 CHAPTER 3. Materials and Methods ............................................................................................37 3.1. M aterials.................................................................................................... 37 3.1.1. Neanderthal and early anatomically modem human fossils ......................................... 37 3.1.1.1. Neanderthals............................................................................................................. 37 3.1.1.2. Early modern humans ..............................................................................................45 3.1.2. Modern populations ...........................................................................................................53 3.2. M ethods ......................................................................................................................................66 3.2.1. Population