We are concerned primarily with the genetic structure of populations, the role of both historical and ecological parameters in determining this structuring, and the elucidation of evolutionary modes which result, as evidenced by morphology, genome structure and organization, molecular divergence, and historical biogeography. 

These approaches combine extensive field and laboratory phases of investigation. Current research focuses on pocket gopher population dynamics in western North America, and on the diversification of rodents and marsupials in Andean wet forests of Peru and Colombia and in the rainforests of Amazonian Brazil.