Doctoral Dissertation Research: Morphological integration between the face and dentition throughout ontogeny

Suny At Stony Brook, Stony Brook NY

Investigators

Abstract

Differences in the size and shape of the face and teeth are often used to determine the relatedness of species. Modern humans, for example, have flatter faces, wider mouths and smaller teeth compared to chimpanzees and our early human ancestors. What is not fully understood is whether the face and teeth are two separate units that can evolve independently or if they are tightly correlated during evolution. In this project, the investigators will study morphological (shape) integration between the face and teeth in humans, chimpanzees and bonobos to test whether specific changes in the size and shape of the face during growth are associated with particular dental developmental events, such as the formation or eruption of the adult molars. The findings from this project will contribute to our understanding of the evolutionary history of humans, and data will be made available for other studies. The results are more broadly applicable for the planning of orthodontic treatments and craniofacial surgeries, and the project will also support minority undergraduate and graduate training. During this two-year project, the investigators will use medical computed tomography (CT) and high resolution microCT scans to generate three dimensional (3D) virtual models of the crania and teeth of over 400 humans, chimpanzees and bonobos from existing skeletal collections. Data will be quantified with 3D landmarks and linear, angular and volumetric measurements, and then binned into five grades of dental development to address specific hypotheses about covariation of the face and dentition. The findings will be relevant to primate systematics, craniodental evolution and ontogeny, and may have clinical implications for understanding craniofacial disorders. The microCT and CT data generated by this project will be compiled into an open-access database for other scientific research, thereby increasing virtual access to museum specimens and preventing further damage to fragile skeletal collections. The project will also promote diversity in biological anthropology, as the co-PI is a female, minority graduate student.