Switching spatial scale reveals dominance-dependent social foraging tactics in a wild primate

PeerJ

article

Alexander E.G. Lee¹  Guy Cowlishaw² 

[1]Department of Zoology, University of Oxford

[2]The Institute of Zoology, Zoological Society of London

[3]Centre of Excellence in Biological Interactions, Department of Biological and Environmental Sciences, University of Jyväskylä

关键词: Social dominance;    Producer-scrounger;    Individual differences;    Competition;    Phenotype-limited strategy;    Resource defence;    Social foraging;    Resource ecology;   

DOI  :  10.7717/peerj.3462

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

When foraging in a social group, individuals are faced with the choice of sampling their environment directly or exploiting the discoveries of others. The evolutionary dynamics of this trade-off have been explored mathematically through the producer-scrounger game, which has highlighted socially exploitative behaviours as a major potential cost of group living. However, our understanding of the tight interplay that can exist between social dominance and scrounging behaviour is limited. To date, only two theoretical studies have explored this relationship systematically, demonstrating that because scrounging requires joining a competitor at a resource, it should become exclusive to high-ranking individuals when resources are monopolisable. In this study, we explore the predictions of this model through observations of the natural social foraging behaviour of a wild population of chacma baboons (Papio ursinus). We collected data through over 800 h of focal follows of 101 adults and juveniles across two troops over two 3-month periods. By recording over 7,900 social foraging decisions at two spatial scales we show that, when resources are large and economically indefensible, the joining behaviour required for scrounging can occur across all social ranks. When, in contrast, dominant individuals can aggressively appropriate a resource, such joining behaviour becomes increasingly difficult to employ with decreasing social rank because adult individuals can only join others lower ranking than themselves. Our study supports theoretical predictions and highlights potentially important individual constraints on the ability of individuals of low social rank to use social information, driven by competition with dominant conspecifics over monopolisable resources.

【 授权许可】

CC BY