This project will investigate the genetic basis of dark body pigmentation (melanism) in high altitude African populations of the fruit fly Drosophila melanogaster. Pigmentation genes identified in Cameroonian and Ethiopian populations will be compared to one already identified in a Ugandan sample to test whether melanism has evolved via distinct genetic pathways. High-throughput DNA sequence data will be collected from fly "introgression lines" (where dark pigmentation has been crossed into lightly pigmented fly stocks) to identify genomic regions containing pigmentation loci. Similar data from wild-collected fly stocks will allow specific genes within these regions to be tested for associations with pigmentation and evidence for natural selection.
This research will significantly improve scientific understanding of how natural selection operates at the genetic level. It will also lay the groundwork for studies that utilize the genetic resources of this model species to pursue the precise mutations underlying melanic evolution. Broader impacts supported by this grant will include (1) the development of instructional materials for the college evolution curriculum, (2) the involvement of a diverse group of undergraduates in research, and (3) the creation of a Virtual Stock Center for Drosophila Population Samples to allow researchers to more efficiently manage living fly stocks.
