Doctoral Dissertation: Neandertal Dental Morpology: Implications for Modern Human Origins

Arizona State University, Scottsdale AZ

Investigators

Abstract

This goal of this research is to shed light on the origin and evolution of anatomically modern humans through the first ever systematic, comparative study of Late Pleistocene hominid dental morphology from an evolutionary perspective. At the core of the debate over modern human origins is the question of the ancestral relationship between Neandertals and anatomically modern humans. This debate focuses on two competing hypotheses for modern human origins: Multiregional Evolution (modern humans evolved from archaic predecessors in many parts of the Old World) or Recent African Origin (modern humans have a single origin, from which they spread, replacing existing archaic humans in the rest of the world). Much of the controversy is over whether or not Neandertals are "too different" from modern humans to have played a significant role in their evolution. The ultimate goal of this research is to assess the relationships among archaic and anatomically modern human samples through an analysis of tooth crown characters. To this end, a large sample of Homo erectus, Middle to Late Pleistocene and Recent human teeth will be analyzed using widely accepted dental morphological standards - the Arizona State University Dental Anthropology - as well as analyses of cusp area and crown shape. Results will be based on a combination of univariate and multivariate statistical techniques and phylogenetic analyses. It is hypothesized that if Neandertals played a significant role in the origin of modern humans, this should be reflected in their tooth crown characters. If this is true, the analysis should demonstrate that (1) Neandertals are dentally more similar to early anatomically modern humans (AMH) from the same geographic region than they are to AMH from other geographic regions, (2) there are regionally distinct dental evolutionary paths toward Recent modern human dental patterns, (3) Neandertals lack a significant number dental characters that are unique to them, and (4) Neandertals and AMH more closely related to each other than either are to other archaic human groups. This study uniquely brings together temporal and geographic axes of dental variation in an analysis of the evolutionary relationship between Neandertals and modern humans. In so doing, it will provide an independent evaluation of current biological and archaeological hypotheses concerning Neandertal affinities and modern human origins.