Chung-I Wu Genetic changes between closely related species or races remain poorly understood; for example, we still do not know whether the biological differences between human and chimpanzee can be attributed to 100 or 1,000,000 bases of our DNAs. An ideal system for the analysis is one that i) are amenable to extensive genetic analysis; ii) show strong biological differences; and iii) are at an incipient stage of speciation. The observed sexual isolation in Drosophila melanogaster is a promising system in these respects (Wu et al. 1995). Females of this species from Zimbabwe do not mate with males from the cosmopolitan collections. This is a widespread phenomenon in southern Africa (Hollocher et al. 1997a) and the sexual behaviors are robust with each autosome exerting strong influences (Hollocher et al. 1997b). The project proposed by the PI will include genetic, behavioral and biochemical analyses.
In studying speciation by sexual selection, it has been very difficult to connect the behavioral evolution with genotypic changes. This proposal presents a system and an experimental approach that make such a connection possible. The long term goal is to understand the genetic, molecular and behavioral mechanisms of species and racial differentiation.
