The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.
This award will support a twenty-four-month research fellowship by Dr. Kenyon B. Mobley to work with Drs. Elisabet Forsgren and Trond Amundsen at the Norwegian University of Science and Technology (NTNU) in Norway, and with Dr. Stephen Shuster at Northern Arizona University.
The study of sexual selection has been greatly enriched in the last two decades by a growing synergy between traditional approaches for quantifying mating behavior and molecular techniques of parentage analysis. Studies of parentage have provided descriptions of genetic mating patterns at an unprecedented level of detail, but how best to use such data to quantify the intensity of sexual selection has not been resolved. Although various methods have been proposed to quantify the strength of sexual selection, there are fundamental disagreements with respect to which methods are most appropriate. One way to overcome this barrier to progress is to compare the various methods proposed within a system in which the strength of sexual selection is known to vary. Such a system exists in the two-spotted goby, Gobiusculus flavescens, a species in which the intensity of sexual selection is temporally dynamic. This project consists of two parts, a field study in conjunction with the Norwegian hosts, and a simulation-based modeling portion in collaboration with the U.S. host. The field study portion consists of field collections of adult females, males and the males' nests harvested at three times during the summer breeding season from two natural populations of G. flavescens from the Swedish West Coast. Microsatellite-based parentage analysis of nest hatchlings provide the necessary data for the evaluation of several statistical methods of estimating sexual selection including the opportunity for selection, the opportunity for sexual selection, the Bateman gradient, the sex difference in the opportunity for selection, the index of resource monopolization and the Morisita index. The modeling portion constructs simulation-based models to test the influence of sex ratios, population density and changing reproductive contributions on the various methods in order to identify the most appropriate method(s) for quantifying sexual selection.
