The proposed research would use an analysis of mitochondrial DNA and proteins to study relationships among members of Cyprinodon variegatus complex of pupfishes. The species of this complex include one wide-ranging species (C. variegatus) that occurs from Massachusetts to Tampico, Mexico and in the West Indies from the Bahamas to Jamaica. The remaining 20 species of the complex occupy much smaller areas, primarily within the range of C. variegatus or near the periphery of its range. the primary objectives are 1) to understand the major patterns of geographic variation in the wide-ranging species, 2) to relate this variation to the evolutionary relationships of the geographically more restricted species, and 3) to use the results to evaluate biogeographic hypotheses and modes of speciation for the complex. Of special interest is the question of whether populations of the wide-ranging species, C. variegatus, might be more closely related to other species than to populations of their own species. If so, then the morphology of the wide-ranging species is primitive for the complex and it comprises one or more cryptic species. The results will be important in future assessments of faunal origins for regions of particular interest in biogeography; for example, the West Indies and the western coast of the Gulf of Mexico.
