Individual, social, and sexual niche traits affect copulation success in a polygynandrous mating system
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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.
Social networks describe with whom individuals consort. The complex patterns of sexual relationships in animal societies can also be expressed as networks of mating-related interactions. During our long-term study on the dynamic social relationships of wild rock hyraxes, we observed complex sexual interactions. Our results show that hyraxes choose mating partners from their available mate pool (or sexual niche) taking into account the traits of their actual mates, other potential mates, and those of their competitors. These findings suggest that the sexual niche, describing the subset of available mating partners, is important for mate choice, with significant implications to the study of sexual selection.
KeywordsMate guarding Mating success Mating system Mating strategy Sexual network Sexual niche Social rank
We are obliged to the many research assistants, undergraduate students, field guides, and park rangers who helped us trap and mark the hyraxes over the last 15 years. We thank the Israeli Nature and Parks Authority (NPA) for permission to work at the Ein Gedi Nature Reserve and the Ein Gedi Field School for hospitality and logistic help. Comments from Ally Harari, Roi Dor, Richard Wagner, and two anonymous referees greatly improved the manuscript, as did editorial comments by Naomi Paz.
Compliance with ethical standards
This study was supported by three grants from the Israel Science Foundation (577/99, 488/05, 461/09).
Conflict of interest
The authors declare no conflict of interests.
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. Permits for capturing, handling, and marking the hyraxes were issued and reviewed annually by the Israeli Nature and Parks Authority (permit numbers: 1999/5983, 2000/8871, 2001/8871, 2002/14674, 2003/14674, 2004/17687, 2005/20737, 2007/27210, 2008/31138, 2009/32871, 2010/37520, 2011/38061, 2012/38400).
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