Why Evolutionary Issues are Reviving Interest in Proximate Behavioral Mechanisms

Information about proximate behavioral mechanisms is required to answer a variety of important questions about the evolution of behavioral and other traits. For instance, theoretical studies of maternal effects indicate that the behavior of parents may have profound effects on the evolution of phenotypic traits in their offspring, and that maternal effects may provide nongenetic pathways for the inheritance of both behavioral and nonbehavioral traits. Similarly, the recent emphasis on genetic correlations among traits cautions that correlations among behavioral traits may have surprising effects on behavioral evolution, and provides further impetus for studies of the proximate bases of behavioral trait syndromes. Finally, the literature on information acquisition suggests that the behavioral processes used in assessment may affect the evolution of behavioral and other traits. For instance, if information is costly to obtain, individuals may prefer familiar to unfamiliar situations. In a social context, a preference for familiar individuals could have a variety of effects on the evolution of social and nonsocial behavior patterns. These and other examples suggest that interest in behavioral processes will continue to grow during the next decade, and that proximate and ultimate approaches to behavioral problems will be more closely integrated than was true in the past.