Rhesus macaque personality, dominance, behavior, and health

Abstract

Previous studies of nonhuman primates have found relationships between health and individual differences in personality, behavior, and social status. However, despite knowing these factors are intercorrelated, many studies focus only on a single measure, for example, rank. Consequently, it is difficult to determine the degree to which these individual differences are independently associated with health. The present study sought to untangle the associations between health and these individual differences in rhesus macaques (Macaca mulatta). We studied 85 socially housed macaques at the Oregon and California National Primate Research Centers, and used veterinary records to determine the number of injuries and illnesses for each macaque. We measured personality using 12 items from a well-established primate personality questionnaire, performed focal observations of behaviors, and calculated dominance status from directional supplant data. All twelve personality questionnaire items were reliable and were used to represent five of the six personality dimensions identified in rhesus macaques-Dominance, Confidence, Openness, Anxiety, and Friendliness (also known as Sociability). Following this, we fit generalized linear mixed effects models to understand how these factors were associated with an animal's history of injury and history of illness. In the models, age was an offset, facility was a random effect, and the five personality dimensions, behavior, sex, and dominance status were fixed effects. Number of injuries and illnesses were each best represented by a negative binomial distribution. For the injury models, including the effects did improve model fit. This model revealed that more confident and more anxious macaques experienced fewer injuries. For the illness models, including the fixed effects did not significantly improve model fit over a model without the fixed effects. Future studies may seek to assess mechanisms underlying these associations.

Individual behavioral differences and health of golden‐headed lion tamarins (Leontopithecus chrysomelas)

“…It has been suggested that high levels of sociality are usually associated with good animal health (Capitanio, 2011; Jin et al, 2013; Robinson et al, 2018). Social grooming, for instance, is important for removal of ectoparasites, maintenance of social bonds, and/or to reduce social tension in groups of nonhuman primates (Dunbar, 1991; Lehmann, Korstjens, & Dunbar, 2007).…”

“…Individual differences in sociality can influence the general health of animals, including primates (Capitanio, 2011). Nonhuman primates involved in more social interactions have more health benefits than less social individuals (baboons, Papio cynoceph alus , Silk, Alberts, & Altmann, 2003; golden snub‐nosed monkeys, Rhinopithecus roxellana , Jin, Su, Tao, Guo, & Yu, 2013; rhesus macaques, Macaca mulatta , Robinson et al, 2018). However, social interactions may also negatively influence health (Rushmore, Bisanzio, & Gillespie, 2017).…”

How long does it take? Reliable personality assessment based on common behaviour in cotton-top tamarins (Saguinus oedipus)

“…Yet, so far, not many animal personality studies have involved common behaviour coding in personality model assessment (some exceptions include Anestis, 2005;Freeman et al, 2013;Garai et al, 2016;Iwanicki and Lehmann, 2015;Konečná et al, 2008;Neumann et al, 2013;Pederson et al, 2005;Robinson et al, 2018;Sussman et al, 2014Sussman et al, , 2013.…”

A multi‐institutional assessment of a short‐form personality questionnaire for use with macaques

“…Consistent personality ratings have been identified for several nonhuman animal species and interest and knowledge of primate personality in particular has been expanding over the past couple of decades (Freeman & Gosling, ; Weiss, ). Studying macaque personality is important because this genus is commonly housed in captivity and understanding more about their individual differences might enhance our understanding of how to provide the best possible care for them (Capitanio, ; Coleman, ; Robinson et al, ; Rouff, Sussman, & Strube, ).…”