Repeated evolution of asymmetric genitalia and right-sided mating behavior in the Drosophila nannoptera species group

摘要

BackgroundMale genitals have repeatedly evolved left-right asymmetries, and the causes of such evolution remain unclear. The Drosophila nannoptera group contains four species, among which three exhibit left-right asymmetries of distinct genital organs. In the most studied species, Drosophila pachea, males display asymmetric genital lobes and they mate right-sided on top of the female. Copulation position of the other species is unknown.