Kin bias and male pair-bond status shape male-male relationships in a multilevel primate society

Abstract Male-male social relationships in group-living mammals vary from fierce competition to the formation of opportunistic coalitions or development long-lasting bonds. We investigated male-male Guinea baboons ( Papio papio ), a species characterized by tolerance and affiliation. live multi-level society, with units one reproductively active “primary” male, 1–6 females, offspring at core level. Together “bachelor” males, several form party, 2–3 parties constitute gang. aimed clarify which degree male relationship patterns varied relatedness pair-bond status, i.e., whether males had primary bachelor status. Data were collected 24 two near Simenti Niokolo-Koba National Park Senegal. Males maintained differentiated equitable affiliative (“strong bonds”) other that stable over 4-year period, irrespective their Remarkably, most strong bonds multiple indicating play an important role cohesion parties. A clear dominance hierarchy could not be established due high uncertainty individual rank scores, yet more likely found low end hierarchy. Average was significantly higher between strongly bonded suggesting kin biases contribute preferences males. Long-term data will needed test how affect tenure ultimately reproductive success. Significance statement living groups may employ different strategies increase success, fighting alliance long-term To shed light on factors shape strategies, we multilevel society ) where are associated small number females “units” while “bachelors.” Strong occurred among were, average, closely related. Bachelor typically bond partners thus fabric baboon societies. Across primate species, neither dispersal nor organization clearly map onto presence routes evolution