My research is devoted to the diversity, systematics, and evolution of tropical fishes. I am interested in all aspects of tropical fish biology, including molecular, physiological, morphological, and behavioral characters, as well as the ecological and geographical circumstances under which these characters evolved. Projects in my lab include descriptive, experimental, and analytical studies of genetic and phenotypic data. These studies are used in part to document the total numbers species in ecologically defined regions, as well as the number of species endemic to these regions. A main objective is to investigate evolutionary questions at cellular, morphological and organismal levels. Further work focuses on testing hypotheses on the origin and maintenance of fish diversity in the tropics, using results from both field and laboratory studies.