Personality in free-ranging Hanuman langur (Semnopithecus entellus) males: subjective ratings and recorded behavior.

The authors obtained behavioral observations and personality ratings for 27 free-ranging Hanuman langur males. Subjects were rated using a questionnaire based on the human Five-Factor Model (FFM). Behavioral observations were taken over 5 months using an ethogram that included 50 behaviors. Principal Component Analysis (PCA) of ratings revealed Agreeableness_(R), Confidence_(R), and Extraversion_(R) components. Each personality dimension was associated with a unique set of observed behaviors. PCA of 36 behavioral indices revealed Dominance_(B), Involvement_(B), and Activity_(B) components. Bivariate correlations showed that Agreeableness_(R) was negatively correlated with Dominance_(B); Confidence_(R) was positively correlated with Dominance_(B) and Involvement_(B) but negatively correlated with Activity_(B); and Extraversion_(R) was positively correlated with Activity_(B). Dominance rank was positively correlated with Confidence_(R) and Dominance_(B) but negatively correlated with Agreeableness_(R) and Activity_(B). These results highlight the comparability of behavioral coding and personality ratings and suggest that some aspects of personality structure were present in the common ancestor of Old World monkeys.