Individual, social, and sexual niche traits affect copulation success in a polygynandrous mating system

摘要

In polygynandrous mating systems, the factors that mediate copulation success and the use of alternative mating tactics, such as mate guarding, are still poorly understood. In the rock hyrax (Procavia capensis), both sexes mate annually with multiple partners during a single month. In order to examine the factors that drive copulation success, we used 494 mating-related observations that were collected over a decade. In our analysis, we used the traits of individual hyraxes as well as the traits of members of their sexual niche, which we defined as their local competitors and potential mates. Using individual traits, we found that overall, female hyraxes rejected copulation attempts more frequently than males, supporting predictions from sexual selection theory. Females who had been mothers in previous years were mate-guarded more by resident males. When we considered the traits of competitors and potential mates in individuals' sexual niche, we found that when resident males had higher-ranking competitors, their copulation success decreased, irrespective of their own traits. Bachelor male copulation success was not influenced by their competitor's social status. Female copulation success was positively affected by maternal status and by social network position. Females that were central in the social network and those that had central female competitors had higher copulation success, supporting the benefits of social cohesion and the importance of the social niche. Thus, our results suggest that in polygynandrous mating systems, copulation success is determined not only by individual quality but also by the social and sexual niches that the individual occupies.