You Should Look a Gifted Mammal in the Mouth: Using Dental Morphology to Understand the Evolution of Mammalian Dentition

Abstract

Dentition is vital to our understanding of mammalian evolution. In this thesis, I use dental morphology as a basis for investigating various phenomena in mammalian dentition. First, I investigate the utility of shape, form, and linear measurement when differentiating species of the genus Mesodma – part of an early group of mammals known as the multituberculates. I found that shape and size metrics reveal different classifications of species. I conclude this chapter by suggesting these methods of differentiation should be investigated further along with the genus. Second, I investigate if cusp shape covariation across the premolar-molar boundary can highlight dental morphology covariance patterns that may contribute to the evolution of molarization in mammals. I found a significant difference in the cusp shape modularity among the two extant orders of hoofed mammals. I infer there are differences in the mechanism of molarization contributing to this differentiation. Further studies are required to infer a mechanism. The studies I present in these chapters showcase how dentition continues to provide important discoveries in the history of mammalian evolution.