Introduction

Patterns of social organization reflect the cooperative and competitive interactions occurring among animals within local populations relating to survival and reproduction. Generally different age/sex classes differ in their spatial dispersion, i.e. group membership and the spatial relationships both within and between groups. Other social relationships may be evident from the patterns of behavior displayed in encounters, for example those signifying dominant/subordinate relations. Dominance is particularly a feature of adult males, which are inevitably competitors for reproductive opportunities. Females in turn may exert some selection over the sire of their offspring. Anti-predator responses are also appropriately considered in this chapter, since the affiliative relationships established among adult females serve largely to reduce the risks of predation, not only for self but also for progeny.

Group structure

The term group refers to a close spatial association between individuals. However, socially the temporal cohesion of the group is relatively more important than short-term spatial proximity. Groups may vary in size, and in the age/sex classes of animals composing them. Different groups may either move independently of one another, or tend to associate together, or space themselves out with respect to other groups. Grouping patterns may furthermore change seasonally, particularly in relation to variations in reproductive activity.

Elephants

Among African elephants, the nuclear group comprises an adult female together with 1–3 immature progeny of varying ages. However, generally one finds 2–4 mothers plus young associated together to form family units typically numbering about 4 to 12 animals (Fig. 7.1).