Drs. Anthony and Alice Echelle of Oklahoma State University will use biochemical data to study the evolutionary relationships of the freshwater pupfishes of North America. The group includes the pupfishes of the genus Cyprinodon (35 species) and five small genera (1-2 species each) of related fishes. The work emphasizes the use of protein variation analyzed by electrophoresis to describe genealogical relatedness among the genera and among the 22 "inland" species of pupfish, followed by the use of mitochondrial DNA variation to describe relationships within a small subset of species, the Death Valley pupfishes and their nearest relatives. Pupfishes constitute the most diverse group of fishes in the three major warm deserts of North America: Mohave, Sonoran, and Chihuahuan. The numerous desert-dwelling pupfish species and the deserts they inhabit have developed in relatively recent geological time. Thus, knowledge of phylogenetic relationships among pupfishes should provide considerable insight into the biogeography of southwestern United States and northern Mexico. The pupfishes also provide an unusual opportunity to test different modes of speciation. A number of pupfishes and the one species of the related genus Megupsilon are threatened with probable extinction in the near future. One outcome of the proposed work is to produce frozen collections of tissues for future biochemical work.
