Durability and flexibility of chimpanzee grooming patterns during a period of dominance instability

Growing evidence from studies on primates and other taxa has shown that the maintenance of long‐term affiliative patterns influences fitness. Thus, understanding how individuals regulate social interactions in response to environmental and social factors contributes to our understanding of the evolutionary basis of sociality. We investigated the durability of affiliation patterns in chimpanzees across three 3‐month periods of varying social uncertainty depending on the degree of stability in the male hierarchy, with a 2‐year gap between each period. Periods were unstable (no clear alpha male), recently stable (new alpha male just established) and stable (alpha male in place for 2 years). We focused on three features of social exchange shared by human and non‐human primates: consistency of exchanges across periods, durability of preferred partners, and degree of reciprocity in each period. We compared male‐to‐male, female‐to‐female, male‐to‐female, and female‐to‐male grooming patterns. Overall, more grooming was exchanged in the stable period. Grooming patterns were not consistent across the three periods, but were only consistent between the recently stable and stable periods for female‐to‐female and male‐to‐female dyads. As predicted from the opportunistic nature of male relationships, male‐to‐male grooming was least likely to be correlated across all periods and males had relatively fewer durable (i.e., preferred partners in all periods) ...
Source: American Journal of Primatology - Category: Psychiatry & Psychology Authors: Tags: RESEARCH ARTICLE Source Type: research