Male-Female Co-evolution in Laboratory Populations of Drosophila melanogaster Subjected to Different Levels of Sexual Conflict

Abstract

The divergent evolutionary interests of males and females in a promiscuous species lead to sexual antagonism or sexual conflict. Males are selected for traits that are competitively superior and harming to females (as a by-product) whereas females are selected for evolving resistance to such male harassment. Reproductive behaviour and life-history of organisms have been predicted to evolve under the influence of such evolutionary conflict. Using Drosophila melanogaster laboratory populations as model system, we studied the mentioned conflict. We used experimental evolution approach. Three outcomes of sexual conflict were studied. First, longevity of populations experiencing different levels of sexual conflict was shown to have evolved. Second, mate induced harassment to females, more interestingly the plasticity of such effect was found to have evolved. Third, we found no evidence of evolution of resource utilization and allocation by females under different levels of sexual conflict. Results are discussed in the light of existing theories of sexual conflict and life-history evolution.