My research emphasizes analysis of evolutionary patterns and the processes that produce them. General areas of interest are functional, developmental, and evolutionary morphology, systematics, and geographical ecology and conservation biology of amphibians and reptiles (see Publications). Current research activities include studies of the functional morphology of feeding in salamanders, evolutionary genetics (allozymes and mitochondrial DNA sequences) in relation to systematics, morphogenesis and its relation to ontogeny and phylogeny, and some aspects of populational and geographical ecology. The focus of most of the work in my group is the large and diverse salamander fauna of North America and the tropical forests of Central America. I also am studying the geography of amphibian declines and disappearances, and factors responsible for these phenomena. My students and postdocs are expected to share some of my research interests, but they study diverse organisms, mainly, but not exclusively amphibians and reptiles.