A Methodology For Nominating Behaviors To Measure Personality Traits In Nonhuman Primates

Applications of personality assessments in non-human primates have yet to be fully investigated. The present study is an exploratory technique for personality assessment that utilizes behavioral measures selected without a priori assumptions, which would permit long-term analysis of personality using behavioral proxies. During August–September, 2012, we studied a group of free-living, provisioned Tibetan macaques (Macaca thibetana) at a tourist site in Anhui province, China. Familiar humans rated 12 adult macaques using a 27-item personality survey for each monkey. Behavioral measures were recorded from observations of the same 12 monkeys. A Principal Component Analysis on the reliable elements of the personality survey revealed five personality components: Insecurity, Reactivity, Boldness, Sociability, and Leadership. Discriminant analyses were used to determine which behavior variables best predicted personality group membership for each of the components. Results indicated that the behavioral measures of avoidance, lunging, fear grinning, self-directed behaviors, touching, proximity, and chasing can be used to significantly (Ps ≤ 0.05) predict the respective personality traits in this macaque population. Strong correlations between Component and Discriminant scores show that behaviors are effective exploratory proxies for personality. General Linear Models of repeated measures also examined the situational effects of provisioning and tourists on the relevant behaviors, with significances found in three of the seven behaviors. Personality components in this population show strong comparability with other publications on primate personality. The behaviors are effective proxies for the relevant personality components in these macaque