The effects of dominance rank on males in social mammals

In many social mammals, conflict among males leads to the establishment of dominance hierarchies, where high-ranking individuals consistently outcompete other group members. Based on sexual selection theory, it is generally assumed that the investment into competition to gain a high dominance rank is one of the key strategies for mammalian males to have higher reproductive success. Previous reviews have however indicated that the relationship between male rank and reproductive success can show substantial variation across mammals. In this programmatic registered report research, we propose to perform a series of meta-analyses to determine 1) whether higher rank is generally positively associated with higher reproductive success for males and which socio-ecological factors explain variation in this association; 2) whether dominance rank is more important for the reproductive success of males than it is for females; and 3) whether variation in the association between male dominance rank and reproductive success is potentially linked to the physiological costs of competition as detected in the levels of glucocorticoid or androgen hormones. Our aim is to identify which factors shape male reproductive strategies in social mammals and how these link to social inequalities. The files in this collection are materials for the pre-study assessment of this registered report.