Sociometrics of Macaca mulatta: II. Decoupling centrality and dominance in rhesus monkey social networks.

The concept of the linear dominance hierarchy and a much less precise notion of a central/peripheral ordering of individuals have been prominent among the ideas about social organization of monkey groups. Although the latter has seldom been quantified, the ranks of individuals in the two orders are usually assumed to be correlated. This paper reports on a longitudinal study of a free-ranging group of rhesus monkeys. The individual histories of progression of dominance rank and an independently determined measure of centrality in the social grooming network are compared among a set of males. Centrality is not a static correlate of dominance rank as implied by the findings of short-term studies. Rather, centrality is a more sensitive indicator of status than is dominance rank, to which it is related in a dynamic fashion. Small changes in dominance rank may be followed by large changes in centrality. An increase in centrality may facilitate rise in dominance rank. These findings suggest a complex psychology of status, rather than a simple causative relation between the two variables.