Abstract DBI 9750278 Caitlin Gabor This action funds an NSF Postdoctoral Research Fellowship in Biosciences Related to the Environment for 1997. This fellowship provides an opportunity for the Fellow to gain additional scientific training beyond the doctoral degree and to pursue innovative and imaginative into the fundamental mechanisms underlying the interactions between organisms and their environment at the molecular, cellular, organismal, population, community and/or ecosystem level in any area of biology supported by the Directorate for Biological Sciences of the National Science Foundation. Each fellowship supports a research and training plan to be carried out in a sponsoring laboratory. The research and training plan for this fellowship is entitled "Reproductive character displacement on mate selectivity in live bearing fish." Reproductive character displacement (RCD) has been proposed to play an integral role in the speciation process. Studies to date suggest that the hypothesis has value but all have been limited in one way or another. This research uses the bisexual sailfin mollie, Poecilia latipinna, and the unisexual mollie, P. formosa, a hybrid with strict maternal inheritance, to evaluate RCD on male mate selectivity for conspecific females versus gynogenetic females along a transect of allopatric and sympatric populations. Allozyme variation is being used to estimate gene flow and its relationship to the spread of the male discrimination trait.
