Biomechanical Evolution of Enamel and the Diversification of Vertebrates

Florida State University, Tallahassee FL

Investigators

Abstract

The evolution of many species was facilitated by changes in feeding capacity. Extensive testing has shown modifications in tooth size, shape, and biting forces are critical determinants of feeding capacity. However, changes in the mechanical performance of dental tissues, which may also play an integral role in this process, are little understood. Data regarding material level mechanical capacity is lacking since dental tissues are minute and preclude most testing protocols. In the present research this problem will be overcome using a new engineering technique called nano-indentation (miniaturized mechanical testing) whereby the measurement of strength, hardness, and scratch-resistance of small materials is feasible. The method will be applied to enamel (the primary contact tissue between food items and the dentition) from a diversity of species with a broad range of feeding abilities. The data generated from this study will serve to tie together the current data on dental morphology and biomechanics. Furthermore it will move the field considerably closer to a comprehensive understanding of the form, function, and ecology of animal feeding--past and present--including how and why our own dentitions function as they do.