Subjective assessment of individual rhesus monkeys

Abstract

Using behaviourally-defined adjectives, observers rated individuals in a colony of rhesus monkeys on a seven-point scale. Principal component analysis of the ratings produced three main components: CI and CII were stable over three years, and CIII arose from the introduction of new items in the third year. Component I can be described as ranging from Confident to Fearful; and adult males scored higher on it than did adult females or one- to five-year olds. Component II ranged from Active to Slow; and adult males scored higher on it than did adult females. Component III ranged from Sociable to Solitary; and adult males scored less on it than did adult females or one- to five-year olds. In addition, there was a positive correlation between scores of mothers and their one year olds on CI and CIII. © 1978 Japan Monkey Centre.