Megan Whitney successfully defended her dissertation on Friday, Dec. 6th. Megan’s research uses paleohisology—the study of ancient tissue microstructure (e.g., bones, teeth)—to understand the evolutionary origins of mammal-like dental traits. Specifically, she looked at how and when certain mammal-like dental features (e.g., having a soft tissue attaching teeth to the jaw) arose in ancient mammalian ancestors (i.e., non-mammalian synapsids), in order to determine what selective pressures may have driven the evolution of certain traits. Megan found that, in general, mammal-like dental traits were acquired in a stepwise fashion, with more deeply nested clades exhibiting more mammal-like, and less reptile-like, dentitions; however, certain traits have evolved convergently in distantly related groups, and this widespread parallelism is probably related to similar dietary adaptations (e.g., herbivory). Megan will begin a postdoctoral research position at Harvard University in January, 2020.
