Male genital lobe morphology affects the chance to copulate in Drosophila pachea

Abstract Introduction Male genitalia are thought to ensure transfer of sperm through direct physical contact with female during copulation. However, little attention has been given their pre-copulatory role respect sexual selection and conflict. Males the fruitfly Drosophila pachea have a pair asymmetric external genital lobes, which primary structures stabilize copulatory complex male genitalia. We wondered if lobes in D. may before or at onset copulation, contacts made. Results tested this hypothesis stock where males variable lobe lengths. In 92 mate competition trials single two males, females preferentially engaged into first copulation that had longer left displayed increased courtship vigor. 53 additional both having partially amputated different lengths, we observed weaker non-significant effect length on success. Courtship durations significantly age when courted simultaneously, compared only one courting male. addition, did not affect once was established. Conclusion Left affects chance engage The morphology trait reproductive success by mediating signals facilitating establishment