Why female crested tits copulate repeatedly with the same partner: evidence for the mate assessment hypothesis

Abstract

That repeated copulation with the same partner within a single fertile period is beneficial to the male is generally accepted, but why it should be adaptive to die female it controversial and clear evidence supporting any hypothesis is lacking. Hunter et al. (1993) presented seven hypotheses explaining repeated mating from the female perspective. Four of them are consistent with the occurrence of male refusal to copulate: females might trade copulations for (1) immediate and/or (2) future material benefits, or use mating as a mechanism for (3) mate-guarding and/or (4) mate-assessment To test these hypotheses in a population of crested tits Parus cristatus, we collected data on variation in female solicitation rate, proportion of male refusal, and extra-pair paternity. We found that (1) female solicitation rate was independent of male condition, (2) die proportion of male refusal was higher in poor-condition males and (3) females paired to poor-condition males sought extra pair paternity. These findings agree with predictions stemming from the mate assessment hypothesis. Therefore, it is suggested that, in crested tits, male response to female copulation solicitation reflects male condition and is' used by females to assess male quality.