PT  - JOURNAL ARTICLE
AU  - Olof Leimar
AU  - Redouan Bshary
TI  - Effects of local versus global competition on reproductive skew and sex differences in social dominance behaviour
AID  - 10.1101/2022.04.13.488121
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.04.13.488121
4099  - http://biorxiv.org/content/early/2022/04/14/2022.04.13.488121.short
4100  - http://biorxiv.org/content/early/2022/04/14/2022.04.13.488121.full
AB  - Social hierarchies are often found in group-living animals. The hierarchy position can influence reproductive success (RS), with a skew towards high-ranking individuals. The amount of aggression in social dominance varies greatly, both between species and between males and females within species. Using game theory we study this variation by taking into account the degree to which reproductive competition in a social group is mainly local to the group, emphasising within-group relative RS, or global to a larger population, emphasising an individual’s absolute RS. Our model is similar to recent approaches in that reinforcement learning is used as a behavioural mechanism allowing social-hierarchy formation. We test two hypotheses. The first is that local competition should favour the evolution of mating or foraging interference, and thus of reproductive skew. Second, decreases in reproductive output caused by an individual’s accumulated fighting damage, such as reduced parenting ability, will favour less intense aggression but should have little influence on reproductive skew. From individual-based simulations of the evolution of social dominance and interference, we find support for both hypotheses. We discuss to what extent our results can explain observed sex differences in reproductive skew and social dominance behaviour.Competing Interest StatementThe authors have declared no competing interest.