Abstract DBI 9750291 Carol E. Lee 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 "Evolution of physiology during habitat transitions." It is subtitled "Repeated invasion of fresh water by a common crustacean." All animal phyla evolved in the sea, and most have successfully made the transition to fresh water. This transition requires adapting to ionic and osmotic changes. The crustacean copepod Eurytemora affinis has recently invaded freshwater reservoirs from salt water multiple times independently. Experiments are designed to determine changes in body fluid regulation during these repeated habitat transitions by combining physiological and phylogenetic information. Insights are being sought on how physiology evolves during biogeographic transitions and how species successfully invade new habitats.
