Goal-directed behavior: Evolution and ontogeny

Introduction The study of goal-directed behavior spans an extraordinarily broad range of disciplines, including philosophy, anthropology, economics, neurobiology, and sociology, to name but a few. Within biology, an evolutionary perspective views patterns of goal-directed behaviors as having been selected over time to maximize survival of the species by prioritizing basic goals such as feeding and reproduction. Whereas this scheme underlies most of the behavioral repertoire of lower level species, it oversimplifies primate behavior. It is particularly restrictive for such complex processes as metacognition. Nonetheless, evolutionary theories provide a starting point for study of the neural underpinnings of complex behavior. For example, microeconomics has used models of animal foraging to explain patterns of economic behavior and formulate mathematical models of economic decisions, such as those made in the stock market (e.g., Schultz et al., 1997). As discussed in more detail below, an evolutionary framework has also been used to explain typical ontogenic changes in patterns of goal-directed behavior, particularly during the adolescent period. Adolescence through the lens of evolutionary theory Adolescence is the developmental period during which individuals transition from a dependent, family-oriented state to an independent, peer oriented state. This fundamental shift is accompanied by refinements in cognitive, emotional and social skills, as well as the acquisition of sexual maturity. Despite wide interindividual variability at any one point in time, the developmental changes associated with adolescence follow a fairly stereotypical sequence. The consistency of this sequence suggests “hard-wired” mechanisms that are most likely selected through evolution to serve species reproduction and survival.