Introduction: Assessments of chimpanzees with the Hominoid Personality Questionnaire (HPQ) has revealed the presence of a broad chimpanzee-specific Dominance factor and five factors analogous to those in humans --- Extraversion, Conscientiousness, Agreeableness, Neuroticism, and Openness. These factors were reliable, generalized to naturalistic and laboratory settings, and related to behavior and subjective well-being. In Japan, 80 chimpanzees at Sanwa were assessed using the Yatabe-Guilford Personality Inventory (YG). We wanted to determine whether the HPQ yields similar personality domains in Japanese chimpanzees and whether they were related to the YG domains and subjective well-being.
Methods: Three raters assessed each of the 80 chimpanzees on the Y-G and HPQ and at least 2 raters assessed 30 additional chimpanzees on the HPQ and a subjective well-being questionnaire.
Results: Principal components analyses (PCA) revealed 4 YG domains and 6 HPQ domains. YG Extraversion was correlated to HPQ Extraversion, Dominance, Openness, and Agreeableness; YG Neuroticism was negatively correlated to all HPQ domains except Openness; YG Depression was negatively correlated to HPQ Dominance and Extraversion; and YG Dominance was correlated to HPQ Dominance, Extraversion, Conscientiousness, and Agreeableness. As expected, HPQ Dominance, Extraversion, and Neuroticism were correlated to subjective well-being.
Discussion: The HPQ can be used to compare the personality of Japanese chimpanzees to that of chimpanzees in other countries or related species, including humans.
