Behavioral role of the sexcombs in Drosophila melanogaster and Drosophila simulans.

The sexcombs were amputated from males of three strains of Drosophila melanogaster and one strain of D. simulans in order to assess the importance of these structures in the sexual behavior of these species. In D. melanogaster the sexcombs are important in attempts to copulate with the female. Their removal delays copulation but does not suppress it entirely. Other aspects of courtship are not influenced by removal of the sexcombs. Strain differences in quanitative aspects of courtship were found, and also in the insemination rates of females by males without sexcombs. The present evidence suggests that the sexcombs are primarily structures adapted to grasping the female securely during the act of intromission.