Stability of social status rankings of female cynomolgus monkeys, of varying reproductive condition, in different social groups.

Abstract

In order test the hypothesis that adult female macaques display a tendency to attain a certain level of social status independent of the social situation, the social status rankings of 41 wild-caught adult female Macaca fascicularis were determined in different social groups. About one-third of the females were intact and housed with vasectomized males. About one-third of the females were ovariectomized and housed with intact males, and the remaining females were intact and housed with intact males in order to allow pregnancy to occur. Within each of these experimental groups, females were housed in social groups of 4-6 females and 1 male, and the constituency of these groups was changed every 3 months for 22 months. Thus, females lived in eight different social groups. The correlations between the social status rankings of individual females while living in different social groups were positive and significant. The majority of the females were either stable dominants or stable subordinates in 75% of the groups in which they lived, which was a significant proportion of the study population. The stability of social status rankings was higher in the ovariectomized than in the pregnant and intact groups; however, this was not a significant difference. In the context of the results of previous studies, these findings suggest that the social status of an individual is the result of both the immediate social environment and some inherent characteristic(s) of the individual that promotes the likelihood that under most social circumstances an individual will display a predictable level of social status.