Data from: The socio-genetics of a complex society: female gelada monkey relatedness patterns mirror association patterns in a multi-level society.

Multi-level societies with fission-fusion dynamics - arguably the most complex animal societies - are defined by two or more nested levels of organization. The core of these societies are modular social units that regularly fission and fuse with one another. Despite their convergent evolution in disparate taxa, we know strikingly little about how these societies form and how fitness benefits operate. Understanding the kinship structure of complex societies could inform us about the origins of the social structure as well as about the potential for individuals in these societies to accrue indirect fitness benefits. Here, we combined genetic and behavioral data on geladas (Theropithecus gelada) to complete the most comprehensive socio-genetic analysis of a multi-level society to date. In geladas, individuals in the core social ‘units’, associate at different frequencies to form ‘teams’, ‘bands’, and, the largest aggregations, ‘communities’. Units were composed of closely related females, and females remained with their close kin during permanent fissions of units. Interestingly, female-female relatedness also significantly predicted between-unit, between-team, and between-band association patterns, while male-male relatedness did not. Thus it is likely that the socio-genetic structure of gelada society results from females maintaining associations with their female relatives during successive unit fissions – possibly in an attempt to balance the direct and indirect fitness benefits of group living. Overall, the persistence of associations among related females across generations appears to drive the formation of higher levels of gelada society, suggesting that females seek kin for inclusive fitness benefits at multiple levels of gelada society.