Reluctant males: why blue monkey males reject female sexual advances

Abstract

Abstract Classical sexual selection theory predicts that males should mate eagerly, yet blue monkey males often reject females’ sexual invitations. We evaluated how males’ responses to female solicitations related to female characteristics, number of males and conceptive females present, and the male’s recent copulations. Using 12 years of data from a wild population, we found that males accepted only 20% of female solicitations. Odds of acceptance (copulation) increased for conceptive females, for females with whom the male copulated recently, and when fewer males were present. Odds of accepting nulliparous females decreased when more conceptive females were available, consistent with market models. Male responses did not relate to female rank or matings with other females the same day. When males responded negatively, nulliparous females were especially likely to receive aggression vs. mere refusal. Overall, males’ decisions to mate with willing females depended both on female characteristics, especially fertility, and on social context.