Current research includes phylogeny of frogs including those known from the fossil record. Paleontology and paleoecology of the Upper Carboniferous and Permian invertebrates. Current research includes systematics and paleoecology of fossil chaetetid sponges. Ph.D., City University of New York, 1976. Mesozoic and Cenozoic fishes.
Current research includes relationships of higher teleost fishes, fossil and recent.
Preparator of vertebrate fossils. Current research interests include the Niobrara Chalk beds of Kansas and their fauna. Paleontology of Permo-Carboniferous vertebrates. Current research includes systematics of late Paleozoic lungfish. Cenozoic history of Florida and South America.