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  • Print publication year: 2008
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9 - Social interactions, social relationships and the social system of spider monkeys



Primates live in a variety of social systems that differ in terms of spacing, grouping and mating patterns as well as the quality of social relationships between individual members (Crook and Gartland, 1966; Clutton-Brock, 1974; van Schaik and van Hooff, 1983; Wrangham, 1987; Dunbar, 1988; Strier, 1994; Janson, 2000; Isbell and Young, 2002; Fuentes, 2007). Three important components of a social system are social organization, social structure and mating system (Kappeler and van Schaik, 2002). In this chapter we focus on the social structure of spider monkeys and its components; social interactions and social relationships. First we start with fission–fusion dynamics, an aspect of social organization that is critical for the understanding of the spider monkeys' social system.

Fission–fusion dynamics

According to Kappeler and van Schaik (2002), social organization describes the size, sexual composition and spatiotemporal cohesion of a social system. The aspect of spatiotemporal cohesion is typically not emphasized in group-living primates because groups are usually viewed as cohesive units. Although variation in spatiotemporal cohesion also occurs in “cohesive” groups, it has mainly been used to characterize species living in so-called “fission–fusion societies.”

The term “fission–fusion” was introduced by Hans Kummer (1971) to describe a social system in which group size can be temporarily adjusted to the availability and distribution of resources by means of the fission and fusion of subunits called parties or subgroups.

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