Meeting Abstract
A key tenet of evolutionary theory is that even closely related species remain reproductively isolated. Indeed, inter-species hybrids are rarely found in the wild. This reproductive isolation extends to the behavioral level, as even closely related species do not attempt to mate with each other. This suggests that genetically hardwired mechanisms enforce such isolation. Male fruit flies of at least three different species use the foreleg, a sensory organ, to inhibit inter-species mating. Gr32a, a chemoreceptor expressed in the foreleg of D. melanogaster, is required to detect inhibitory pheromones of other Drosophilid species in order to preclude inter-species mating. Moreover, Gr32a+ neurons are necessary and sufficient to inhibit such behavior. Given that the sensory pathway for inhibiting inter-species mating is conserved, we are using modern genetic tools to understand how the neural circuits underlying mate choice have evolved in disparate fly species. We generated novel transgenic lines in D. melanogaster and other fly species to determine whether Gr32a functions in an analogous manner across species. These studies involve examining the control of Gr32a expression and its function in different species. Taken together, my studies will lead to a better understanding of how behavioral reproductive isolation has evolved.
