Do Primate Females Gain Nonprocreative Benefits by Mating with Multiple Males? Theoretical and Empirical Considerations

Abstract

In Batsman's 1 landmark experiments, he placed male and female fruit flies in bottles with varying numbers of opposite-sex mates. Male production of offspring increased with increasing numbers of female mates, but female production of offspring did not increase with increasing numbers of male mates. This phenomenon was caused by a fundamental reproductive difference between the sexes: Fertilization and gestation occur In the female, which limits her maximum reproductive output compared to that of males. 2 From an adaptationist perspective, this insight led to the generalization that males should mate indiscriminately, whereas females should be more discriminating. Empirical observation has not supported the generalization that females are always so choosy, however. In a wide variety of animals, females are known to mate with multiple partners. 3,4.