Observations of group introductions in lowland gorillas

Data concerning group interactions subsequent to introductions of novel or familiar animals comes primarily from studies of a few cercopithecine species. This investigation attempted to supplement these data with descriptive observationd of gorillas during, and for a period following introductions. A unisexual group of females and a heterosexual group were formed. Departures from the cercopithecine pattern were observed in terms of the frequency of aggression, as well as the time course and the level of agonistic activity following group stabilization. Agonism remained high and in one case comprised 80% of the interactions six months after the introduction. The female group evidenced elevated levels of agonism as well as a possible means of appeasing such behaviors. The results are discussed in terms of the apparent absence of a status hierarchy in gorillas.