The Lives of Others: Social Rationality in Animals

Why do animals attend to the lives of others? Social situations have provided important pressures in the evolution of behavior. In fact, some have argued that the complexities of social life require sophisticated mental abilities such that individuals of highly social species will evolve intelligent ways to cope with this complexity. The chapter explores three key components critical for social decision making. First, although the social milieu might be complex and ever changing, the use of simple decision mechanisms such as heuristics or "rules of thumb" may allow animals to navigate this complexity. Simple rules can provide good responses to complex problems. Reasonable decision mechanisms cannot be developed without considering the requisite cognitive capacities needed to implement these mechanisms. For example, investigating these cognitive capacities has been useful in reassessing the decision mechanisms used in cooperative situations. Finally, the animal literature is particularly useful for testing questions of ecological rationality-where decision rules are adapted to the structure of the physical and social environment-because different species have evolved in different environments. Each species' environment may uniquely shape its decision processes, and the social environment is a particularly important selective force on decision making. In summary, decision mechanisms, cognitive capacities, and the environment of a species must be investigated to understand properly its decisions. This perspective integrates the evolutionary and cognitive study of decision making to explore how animals navigate the complexities of their social worlds.