Personality and subjective well‐being in captive male western lowland gorillas living in bachelor groups

Abstract

The purpose of this study was to determine the personality structure of eight male gorillas (five silverbacks and three blackbacks) housed at the Sedgwick County Zoo in Wichita, Kansas and to determine if personality predicts behavior and subjective well-being in male gorillas living in bachelor groups. We used the Hominoid Personality Questionnaire which contains 54 descriptive adjectives with representative items from the human five-factor model. Rates of 12 behaviors that are broadly defined as agonistic or affiliative were independently recorded and calculated. Principal components analysis yielded three reliable personality factors: Dominance, Extraversion/Agreeableness, and Conscientiousness. These results are the first potential quantitative evidence for a Conscientiousness factor in a hominoid other than chimpanzees and humans. This suggests that Conscientiousness originated with the common ancestor of male gorillas and humans around 10 million years ago. These results indicate that humans can reliably assess the personality and subjective well-being of captive male gorillas living in bachelor groups with robust levels of inter-rater reliability and validity. Furthermore, personality can accurately predict behavior (r = 0.79; n = 13) and subjective well-being (r = 0.83; n = 5) in gorillas and provide convergent and discriminant validity for the personality factors. The results advocate for the use of personality questionnaires in the captive management of bachelor gorillas over long-term multi-institutional behavioral studies.

Personality in Bonobos

“…These factors showed interrater reliabilities and test-retest reliabilities comparable to those of human personality factors (e.g., Costa & McCrae, 1992) and personality traits and dimensions in other species (Bell, Hankison, & Laskowski, 2009;Gosling, 2001). The bonobo Assertiveness factor was similar to chimpanzee dominance (King & Figueredo, 1997;Weiss et al, 2007Weiss et al, , 2009 and to components and factors identified in other primate species (Eckardt et al, 2015;Konečná et al, 2008;Konečná et al, 2012;Morton et al, 2013;Schaefer & Steklis, 2014;Weiss et al, 2006Weiss et al, , 2011. In contrast, the evidence for chimpanzee analogues of extraversion and attentiveness was weak.…”

“…Extraversion in bonobos differed from dimensions labeled extraversion, sociability, or friendliness in other species (Eckardt et al, 2015;King & Figueredo, 1997;Konečná et al, 2008;Morton et al, 2013;Schaefer & Steklis, 2014;Weiss et al, 2006Weiss et al, , 2007Weiss et al, , 2009Weiss et al, , 2011. The items "solitary," "depressed," "autistic," and "individualistic" all had negative loadings on this factor.…”

“…In chimpanzees (King & Figueredo, 1997;Weiss et al, 2007Weiss et al, , 2009, these items defined high dominance and high conscientiousness. In gorillas, these items defined high dominance (Eckardt et al, 2015;Schaefer & Steklis, 2014). In rhesus macaques, these items defined high confidence, friendliness, and activity (Weiss et al, 2011).…”

“…Traits such as "solitary" and "depressed" are associated with low extraversion in humans (Costa & McCrae, 1992) and chimpanzees (King & Figueredo, 1997), low sociability in brown capuchin monkeys (Morton et al, 2013), and low friendliness in rhesus macaques (Weiss et al, 2011). The item "individualistic" is associated with extraversion in chimpanzees (Weiss et al, 2009) and components or factors labeled sociability (Eckardt et al, 2015) or extraversion (Schaefer & Steklis, 2014) in gorillas. The item "individualistic" is associated with extraversion in chimpanzees (Weiss et al, 2009) and components or factors labeled sociability (Eckardt et al, 2015) or extraversion (Schaefer & Steklis, 2014) in gorillas.…”

Studying primate personality in zoos: implications for the management, welfare and conservation of great apes

“…Vazire et al, 2007); therefore, links between the two have been found and tend to be evident. For example, gorilla Dominance is related to received and given displacement (negative and positive, respectively) (Kuhar et al, 2006;Schaefer & Steklis, 2014); and Extraversion/Agreeableness is related to affiliative, grooming, playing, approach and touching behaviours (Schaefer & Steklis, 2014). Similarly, Chimpanzee Extraversion is related to affiliative behaviour (Pederson et al, 2005;Massen & Koski, 2014).…”