Boesch: Primate Social Evolution 1 The Ecology and Evolution of Social Behavior and Cognition in Primates

An animal’s social life presents him with a constant yet varying series of challenges that they must solve daily if they want to survive and reproduce. An evolutionary approach to the evolution of social behavior and cognition predicts the convergent emergence of similar patterns and abilities in animal species facing similar challenges, as well as the emergence of a large diversity of behavioral and cognitive abilities within species facing different socio-ecological challenges. In primates, evidence supporting these predictions contradicts a Cartesian approach that many psychologists have adopted favoring captive studies and minimizing the role of experience and ecology. Social grouping is largely the result of a balance between increased predation protection, which is higher in larger groups, and decreased intra-group feeding competition, which is less intense in smaller groups. However, within such optimally sized groups, a great deal of flexibility in how social life can be organized is still possible. Cooperation, altruism, and reciprocity are observed with different levels of prevalence by individuals living in different ecological niches. In many monkeys and chimpanzees, we see that ecological factors play a decisive role in favoring the evolution of cooperation and altruism. The underlying cognitive abilities required to master them will develop according to how important the abilities are for the survival of the individuals. Different aspects of the ecological niche select for different abilities, which prevents a simple model of the evolution of social behavior and cognition. As a rule, the captive environment, a habitat that is particularly challengeand danger-poor, selects for less demanding social cognitive development in many primate species, including humans. If we want to gain a better understanding of the evolution of social behavior and cognition, more research should be directed towards primates that face different types and levels of ecological challenges.