PERSISTENT COURTSHIP REDUCES MALE AND FEMALE LONGEVITY IN CAPTIVE TSETSE-FLIES GLOSSINA-MORSITANS MORSITANS WESTWOOD (DIPTERA, GLOSSINIDAE)

Where males can increase their mating success by harassing females unt il they accept copulation, harassing tactics can be expected to evolve to a point where they have costs to the longevity of both sexes. By e xperimentally manipulating the sex ratio in captive groups of tsetse f lies Glossina morsitans morsitans, we demonstrated that the longevity of females declines where sex ratios are biased toward males, while th e longevity of males declines where the sex ratio is biased toward fem ales, Neither irradiation of males nor prevention of copulation by blo cking or damaging the external male genitalia increased the longevity of females caged with them, suggesting that female longevity was reduc ed by the physical aspects of male harassment rather than by component s of the ejaculate.