Abstracts (first author)
Understanding promiscuity: when is seeking additional mates better than guarding an already found one?
Male monogamy is expected when a male spends his entire time budget guarding one female rather than acquiring multiple mates. The consensus from theoretical work is that mate-guarding intensifies with an increasing male bias in the adult sex ratio (ASR). Given that both male and female biased ASRs are observed, why is it that promiscuity is more common than male monogamy? We address this question with a model that allows males to combine paternity protection from guarding with searching for additional females to maximize paternity, i.e. temporally limited guarding. In contrast to existing models we combine pre- and postcopulatory mate guarding in a single model. Our model confirms that the ASR is an important predictor for mate guarding duration. Guarding durations increase with the number of male competitors and decrease with a decrease in female availability. However, a male biased ASR alone does not select for male monogamy. We identify conditions for promiscuity, temporally limited guarding and monogamy. These confirm our suspicions that frequency-dependent payoffs explain the relative infrequent occurrence of male monogamy.