Using behaviour observations to study personality in a group of capuchin monkeys (Cebus apella) in captivity

This article presents a novel approach to the study of primate personality and illustrates it with a study of capuchin monkeys. While most personality studies with capuchin monkeys have used rating questionnaires, the research method of this study relies instead on direct behaviour observations. In an effort to capitalize on the full richness of behavioural observation data, we used both statistical and non-statistical methods to analyse data from behavioural observations of a group of capuchin monkeys in captivity. Interest in capuchin monkeys as a species has increased due to their cognitive capacities, behavioural flexibility and complex social structure, as well as many similarities with great apes in dimensions of personality. In this study we focus in three aspects of personality: Diversity, flexibility and complexity. Our results provide a detailed picture of these aspects of capuchins' personality, including the degree of "predictability" and "unusualness" of individual capuchins' behaviour.