Mating season influence on allogrooming in a confined group of Japanese macaques: A quantitative analysis

Abstract

Three different quantitative parameters (frequency, duration and distribution) were used for studying allogrooming behavior in and outside the mating season in a Japanese macaque social group confined at the Rome Zoo. On the whole, 106 hr of observations were made using an “all occurrences” recording technique. Although individual grooming scores were collected, the quantitative analyses were mostly focused on the relationships between and within the age/sex classes. The mating season caused two basic changes in allogrooming: (1) an amount increase; and (2) a widening of individuals' range of interactions. Strikingly, the former variation proved to be widely independent of the latter. Relationships between the age/sex classes changed so that the mature females became the main target of grooming from other group members, male and female. On the contrary, two interactional trends did not seem to be affected by the mating season: the tendencies to groom agemates chiefly and to interact with relatives closely. However, the reorganization of grooming relationships did not appear to weaken the group cohesion.