Tibetan macaque males at Huangshan (Macaca thibetana huangshanensis) display highly skewed mating success and highly asymmetric patterns of aggression, but also high levels of tolerance. We examined affiliation, tolerance and agonistic support to test the hypothesis that increased tolerance in otherwise despotic males may occur when high-ranking males require support from other males to prevent (1) potentially destabilizing revolutionary coalitions

We examine variation in grooming kin bias intensity (KBI) among wild female Tibetan macaques (Macaca thibetana huangshanensis) in one group over time. We test three hypotheses based on socioecological theory, time constraints and risk-related responses. Only the time constraints hypothesis was supported. Grooming KBI was higher when the group was larger, but was unrelated to other indicators of within-group competition. Allies were not necessarily

Human mothers interact emotionally with their newborns through exaggerated facial expressions, speech, mutual gaze, and body contact, a capacity that has long been considered uniquely human [1,2,3,4]. Current developmental psychological theories propose that this pattern of mother-infant exchange promotes the regulation of infant emotions [4,5,6] and serves as a precursor of more complex forms of social exchange including perspective taking and empathy.