Intraspecific Variation In Primate Dental Wear: The Role Of Environment And Diet

<p>Patterns of overall tooth wear (i.e., dental macrowear) reflect the cumulative effects of food processing, with differential tooth wear affecting survival, health, and life history. The structure of teeth (occlusal morphology, enamel thickness, enamel structure) is generally well adapted to specific diets, so that even as teeth wear, they remain capable of adequately processing food. Tooth wear results from a variety of causes, including food properties (abrasion), chemical erosion, contact between teeth (attrition), and/or extraneous grit. However, the mechanics of wear remain poorly understood. The goal of this project is to identify the proximate causes of wear in a single primate species (Lemur catta), across and within multiple habitats, and across seasons in a highly seasonal environment (southern Madagascar), thus providing a critical framework for understanding intraspecific variation in primate, and thus mammalian, tooth wear. This project will combine new data on food properties, plant phytoliths, and exogenous grit, with detailed knowledge of feeding behavior and ecology, to assess the role of each on tooth wear. Patterns of dental macrowear will be assessed using dental topographic analyses, while the effects on tooth wear by phytoliths and grit will be determined using dental microwear texture analyses. Intellectual Merit As this study uniquely combines a direct understanding of primate behavior, plant use, habitat differences, plant food properties, and the role of grit and phytoliths, these results should inform how these processes work together to create variability in patterns of tooth wear. Broader Impacts This project will aid the development of Malagasy biology students with the skills necessary to contribute to the study and conservation of endangered wildlife in Madagascar. It will also provide undergraduate student research opportunities at the University of North Dakota and the University of Arkansas (both EPSCoR states), and will build on the project's record of K-12 outreach in the U.S. and in Madagascar.</p>