Personality dimensions and their behavioral correlates in wild Virunga mountain gorillas (Gorilla beringei beringei).

Abstract

Studies of animal personality improve our understanding of individual variation in measures of life history and fitness, such as health and reproductive success. Using a 54 trait personality questionnaire developed for studying great apes and other nonhuman primates, we obtained ratings on 116 wild mountain gorillas (Gorilla beringei beringei) monitored by the Dian Fossey Gorilla Fund's Karisoke Research Center in Rwanda. There were 8 raters who each had more than 1.5 years of working experience with the subjects. Principal component analyses identified 4 personality dimensions with high interrater reliabilities-Dominance, Openness, Sociability, and Proto-Agreeableness-that reflected personality features unique to gorillas and personality features shared with other hominoids. We next examined the associations of these dimensions with independently collected behavioral measures derived from long-term records. Predicted correlations were found between the personality dimensions and corresponding behaviors. For example, Dominance, Openness, Sociability, and Proto-Agreeableness were related to gorilla dominance strength, time spent playing, rates of approaches, and rates of interventions in intragroup conflicts, respectively. These findings enrich the comparative-evolutionary study of personality and provide insights into how species differences in personality are related to ecology, social systems, and life history.

Common marmoset (Callithrix jacchus) personality.

“…This may be more difficult for species that are taxonomically distant from humans; however, at least in primates, the structures derived using behavioral measures and ratings are often highly similar (compare, for example, Table 3 in Neumann et al, 2013 and Table S6 in Adams et al, 2015 or Table 6 in Morton et al, 2013 and Table 3 in Uher & Visalberghi, 2016). Moreover, construct validation typically is post-hoc without predictions of the expected correlations (but see Eckardt et al, 2015 and. We thus urge future researchers to a priori consider what correlations one should and should not expect based on the functions of these behaviors in the species of interest.…”

“…Correspondence of rated components and measured behaviors tends be better in studies on ape personality (Eckardt et al, 2015;Pederson et al, 2005;Freeman et al, 2013). As has been discussed elsewhere (e.g., Uher, 2008;Koski, 2011b), this may be because the rating method depends on the degree to which people can intuitively aggregate the study species' behavior into meaningful categories.…”

“…For example, in macaque species (Weiss et al, 2011;Adams et al, 2015), brown capuchin monkeys (Morton et al, 2013), and in mountain gorillas (Eckardt et al, 2015), traits related to gregariousness and sociopositive behavior define one factor, whereas they define two factors in chimpanzees (King & Figueredo, 1997), orangutans (Weiss et al, 2006), and in humans (Costa & McCrae, 1992). On the other hand, in bonobos, most traits related to gregariousness and sociopositive behavior define a single factor, but a few related to gregariousness define a small additional factor .…”

“…Research on nonhuman primate personality bucks this trend (e.g., Koski, 2011a;Massen et al, 2013;Neumann et al, 2013;Konečná et al, 2008Konečná et al, , 2012Morton et al, 2013;Garai et al, 2016;Weiss et al, 2006Weiss et al, , 2007Weiss et al, , 2009Weiss et al, , 2011Weiss et al, , 2012aWeiss et al, ,b, 2015Eckardt et al, 2015;Neumann et al, 2013;Adams et al, 2015;Uher & Visalberghi, 2016).…”

A human model for primate personality

“…However, studies have revealed associations between primate personality and measures related to social status [76,77], learning, cognitive performance and information processing [78][79][80][81], and health [82,83].…”