Function and wear pattern analysis in Neanderthal and early 'Homo sapiens' dentitions

Occlusal movements during chewing produce tooth wear. Surface area and spatial orientation of wear facets are closely related to the direction of jaw movements. Various studies, including the analysis of stable isotopes from bone and teeth, dental microware and faunal remains, have led to hypotheses that Neanderthals were wide-ranging meat eaters while early 'Homo sapiens' were a more opportunistic feeder with a broader dietary spectrum. In this study, wear pattern analysis derived from optical 3-D topometry is used to reconstruct jaw movements of the two species in order to interpret their diet. In Neanderthals buccal and lingual Phase I facets are well developed, whereas Phase II facets are less developed. First molars show a strong facet 5, especially in the upper molars, probably caused by the presence of Carabelli features. In addition, the wear areas show large, marked edges. In contrast early 'Homo sapiens' molars show prominent Phase I and II facets with more rounded wear facet margins. The two species display a clear difference in tooth wear. Early 'Homo sapiens' possess a generalized wear pattern with a well developed Phase II grinding activity that indicates the mastication of many varieties of food, including hard and fibrous materials, whereas Neanderthals appear to have been more specialized with a narrower diet. Supported by EU Marie Curie Training Network MRTN-CT-2005-019564 EVAN.