Occlusal Wear Pattern Analysis of Functional Morphology in Neanderthals and Early Homo sapiens Dentition Dissertation zur Erlangung des Doktorgrades der Naturwissenschaften Vorgelegt beim Fachbereich Biowissenschaften der Johann Wolfgang Goethe-Universität in Frankfurt am Main von Luca Fiorenza aus Rom Frankfurt 2009 (D30) Von Fachbereich Biowissenschaften der Johann Wolfgang Goethe – Universität als Dissertation angenommen. Dekan: Prof. Dr. A. Starzinski-Powitz Gutachter: Prof. Dr. F. Schrenk and Prof. Dr. G. Weniger Datum der Disputation: 09-11-2009 ii Acknowledgements This dissertation would not have been possible without the encouragement and support of many people. I wish first to thank Ottmar Kullmer, the supervisor of my doctoral studies, for involving me in this project, for continuously motivating me and giving me precious and useful advice for the past three years. I would like also to thank my dissertation advisors, Prof. Friedemann Schrenk and Prof. Gerd-Christian Weniger for their time and participation. I would like to gratefully acknowledge the following curators for access to comparative and fossil specimens: Almut Hoffmann (Museum für Vor- und Frühgeschichte, Berlin, Germany), Maria Teschler Nicola (Naturhistorisches Museum Wien, Vienna, Austria), Marta Dočkalová (Moravské Zemské Muzeum, Anthropos Institute, Brno, Czech Republic), Bence Viola (Department of Anthropology, University of Vienna, Austria), Yoel Rak (Department of Anatomy and Anthropology, University of Tel Aviv, Israel), Fabio Parenti (Istituto Italiano di Paleontologia Umana, Rome, Italy), Chris Stringer and Rob Kruszynski (Natural History Museum of London, England), Angiolo del Lucchese (Museo Preistorico dei Balzi Rossi, Ventimiglia, Italy), Loretana Salvadei (Museo Nazionale Preistorico Etnografico ―Luigi Pigorini‖, Rome, Italy) and Erik Trinkaus (Department of Physical Anthropology at Washington University in Saint Louis, USA). I need also to express all my gratitude to the people of the Department of Paleoanthropology and Messel Research at the Senckenberg Research Institute, and in particular to Christine Hemm-Herkner for the pleasant company during the numerous trips around the world for collecting data; to Birgit Denkel-Oswalt for her incredible patience and kindness and because without her I would be probably lost in the German bureaucracy; to Ulrike Menz for her great helpfulness and copy-editing the German thesis summary; to Tim Schikora for his help with German proofreading and to Elke Pantak-Wein for her precious assistance. Moreover I give special thanks to Jeremy Tausch for his friendship and patience for copy-editing this manuscript and to Stefano Benazzi for his important contribution in improving the quality of the OFA method and, of course, for his friendship. I would not be able to make any mould or cast without the support and advice from Olaf Vogel and from all the people of the Geological Preparation Lab and the Zoological Taxidermy Lab of the Senckenberg Museum. Bence Viola deserves another special thank-you for his advice in dental moulding/casting, for helping me in surface-scanning the original fossils in Brno and for providing me with the dental casts of Bushmen, Fuegians and Australian aborigines. I owe all my gratitude to iii Emiliano Bruner where beyond his friendship, he helped me throughout my scientific career since university, giving me precious advice, motivating and encouraging me to improve. I will never stop to thank Matthew Westwood who helped me to copy-edit this manuscript. I feel really sorry for him since I have almost forced him to read pages and pages full of technical and ―strange‖ scientific terms. It must be really boring. Thanks mate! I also owe a debt to the PAST (Palaeontological Statistics) community and to Prof. Brooks Ferebee (Department of Mathematics, University Johann Wolfgang Goethe-University of Frankfurt) for their precious support, which helped me to solve statistical problems I faced during my PhD. I would also like to express my gratitude for being a part of EVAN (European Virtual Anthropology Network) which gave me the opportunity to participate in interesting scientific events where I met many great people. This research was supported by EU Marie Curie Training Network MRTN-CT-2005-019564 EVAN. Last but not least, I have to thank all my friends and especially my family that despite 1000 km of distance between us, are always with me. I am also indebted to my girlfriend Iva who always left a hot meal on the table, understanding and supporting me despite the fact I have ―preferred‖ to spend my time with my computer in writing and re-writing my thesis instead to be with her. iv Summary Very little is known about the occlusal wear pattern in the Neanderthal posterior dentition. Usually dental wear is closely related to the physical properties of the ingested food, and consequently can be used to obtain information about diet. Neanderthal dietary reconstructions have been mostly based on the analysis of accompanying faunal remains and isotopic signatures of bones and tooth enamel, suggesting that they exploited larger portions of animal proteins from large and medium-sized herbivores. Probably these studies may do not reflect the bulk diet, tending to underestimate plant consumption and to overestimate meat consumption. In the present work the occlusal wear pattern of maxillary molars of Homo neanderthalensis (N=19) and early Homo sapiens (N=12)have been analyzed, applying non-destructive methods based on virtual three-dimensional polygonal models generated from surface scanning of dental casts. The sample groups occupied different geographical areas at different chronological times. The 3D digital tooth models were analyzed using the ―Occlusal Fingerprint Analysis‖ (OFA) method (Kullmer et al. 2009), describing and quantifying the occlusal wear pattern derived from two wear facet angles (dip and dip direction), wear facet area and occlusal relief index (ORI). The OFA method provides information about the dynamics of the occlusal relationships and their function, permitting the reconstruction of the mandibular movements responsible for the contacts created during the chewing cycle. Since jaw movements and diet are closely related, the results obtained, can be used to interpret the diet of the two Pleistocene hominin species. In order to evaluate how dietary differences influence the occlusal wear pattern, upper molars of modern hunter-gatherers (N=42) with known diet and different dietary habits, have been included in the sample and compared with those of Neanderthals and early Homo sapiens. Results show that within the modern hunter-gatherers sample, the occlusal wear pattern of carnivorous populations differs from those who relied on a mixed-diet. In particular, the study of relative facet areas clearly distinguish meat-eaters from mixed-diet hunter-gatherers, while ORI results and wear facet inclinations (dip angle) seem to reflect directly the abrasiveness of the diet, including the influence of exogenous materials during food preparation. The Neanderthal occlusal wear pattern is characterized by an ecogeographic variation, suggesting the exploitation of different food resources. In particular Neanderthals who inhabited relatively warm environments of southern Europe and the Near East exhibit an occlusal wear pattern different from those of meat-eaters hunter-gatherers from tempered and v cooler regions, displaying some features similar to those of Bushmen. These results suggest the exploitation of a broad variety of food sources. The analysis of the occlusal wear pattern in Neanderthals and early Homo sapiens who inhabited Europe during the cooler Oxygen Isotope Stage 3 (OIS3) shows many similarities between the two hominid species. These results indicate the exploitation of similar and low-diversified food sources, based mostly on the consumption of animal proteins, as suggested through the clear similarities with the wear patterns found in modern meat-eaters hunter-gatherers. In both studied groups, Neanderthals and early Homo sapiens the occlusal wear pattern is characterized by high ORI and dip angle values, suggesting the intake of a low-abrasive diet, probably due to the absence of sophisticated food preparation techniques introducing external silica grains, e.g. from soil (grinding of seeds) or plant cells, as those, seen in modern hunter-gatherer populations. The analysis of the occlusal fingerprints in Neanderthal and early European Homo sapiens upper molars suggests that both species followed very similar adaptive dietary strategies, based on a distinctive versatility and flexibility in the daily diet, depending on availability of resources according to environmental circumstances. vi Table of Contents Acknowledgements ......................................................................................................................... iii Summary ............................................................................................................................................ v Table of Contents ........................................................................................................................... vii List of Figures .................................................................................................................................. xi List of Tables ................................................................................................................................... xv Abbreviations ................................................................................................................................