Friendship affects gaze following in a tolerant species of macaque, Macaca nigra

Gaze following, the ability to follow the direction in which others are looking, is thought to allow individuals to acquire valuable information from their physical and social environment. Recent studies, using artificial stimuli, showed that gaze following can be modulated by social factors such as dominance or social context, suggesting the importance of integrating these […]

Friendship among Adult Female Blue Monkeys (Cercopithecus mitis)

A study group of blue monkeys in the Kakamega Forest, Kenya, provides data on friendly relationships between adult females. Females are invariably antagonistic toward members of other groups, and collaborate with their own groupmates in defending territorial boundaries. Females are primarily responsible for these aggressive intergroup encounters, which occur every other day on average. Encounters […]

Longitudinal stability of friendships in rhesus monkeys (Macaca mulatta): Individual- and relationship-level effects

The longevity of children’s friendships is influenced by a multitude of individual- and relationship-level attributes, but little is known about the factors that impact friendship maintenance in nonhuman primate juveniles. We investigated whether the following predicted the longitudinal stability of friendships in juvenile rhesus monkeys (Macaca mulatta): (1) individual characteristics including sex, dominance rank, matriline […]

Stable heterosexual associations in a promiscuous primate

Close associations between adult males and females are rare among group-living, nonmonogamous mammals but may mark the transition from life in promiscuous bisexual groups to groups of pairs or pair living. Although heterosexual friendships have been described in baboons, these are short-term affairs serving as protection against infanticide and thus tightly linked to the presence […]