Offspring sired by subordinate red deer males under controlled conditions: did some females prefer not to mate with the alpha male?

Abstract

Both male-male competition and female choice are important forces in sexual selection that may act in concert. In red deer (Cervus elaphus), rutting activities related to male-male competition are highly conspicuous and have received most research attention. However, there is increasing evidence that females can gain by selecting mates. Due to the additive genetic benefits of a sire’s dominance rank, females may prefer them as mates, so that selection for male traits associated with dominance can be reinforced by female choice. On the other hand, recent evidence suggests that females might prefer male features not related to dominance and thus affect the distribution of mating outcomes. This predicts mating with less dominant males, but no study has so far investigated to which extent some females may do so when the dominant male is available. Here we use controlled captivity conditions to study whether females mate with subordinate males when dominant males are present. By means of parentage analyses conducted after genoty** the offspring, we found that dominant males did not sire all the offspring, the mean percentage of offspring sired by subordinate males being 13.03%. This result has consequences for the evolutionary reinforcement of components of sexual selection in red deer and might be used as a starting point for future studies on the red deer mating system and sexual selection.