Abstract
Intersexual selection involves the competition whereby individuals compete for mates through direct interaction with prospective mates. There should generally be sex-specific optima for mating frequency between males and females to the extent that they invest unequally in offspring (parental investment). Sexual conflict theory predicts that males will evolve traits to manipulate females to mate sub-optimally (e.g., too often). D. melanogaster females mate with multiple males over their lifetime exposing them to harm through increased risk of disease, predation, and increased exposure to toxic seminal fluids. Decreased exposure to toxic seminal fluid proteins has been shown to increase female lifespan and lifetime fecundity in a dose dependent manner. Therefore, it is hypothesized that pressure from males results in excessive mating that reduces females’ lifespan and decreases females’ overall lifetime reproductive success. Natural selection should favor females with traits that lower the number of mating partners, or otherwise resist the deleterious effects of male manipulation. This study aimed to determine whether there is variation in female mating rate and how such variation correlates with fitness. Additionally, the effect of male genotype on female mating rate and reproductive fitness was tested. There was no significant relationship between mating rate and female offspring production for females mated with any of three male genotypes. Wild-type females mated significantly fewer times with males of the DA outcross genotype than with males of the CA outcross genotype or LHM wild-type males, indicating that male genotype can affect female mating rate.