Epigenetic rules and Darwinian algorithms: The adaptive study of learning and development

Recent efforts toward a Darwinian psychology of human behavior will profit from taking account of prior investigations of proximate phenomena and adaptive mecha-nisms conducted within the science of biology, and from realizing that adaptive sig-nificance and underlying mechanisms must be investigated in concert. Contrary to some recent arguments, evidence of adaptive design is usually manifested initially and most prominently in the behavior (or other “ultimate ” phenotypic expressions) of organisms, human or nonhuman, rather than in underlying psychological, physiological, or de-velopmental mechanisms, which are often obscure, and in any case, as adaptive mech-anisms, must be investigated secondarily. The reason is that selection acts most directly on behavior, and on its underlying mechanisms only as they influence the behavior. This is as true for learned and cultural behaviors as for any others. Adaptive significance of behavior, and evidence of its underlying design, is thus examined only by studying the behavior itself, its complexity, the situations in which it is expressed, and its effects in different situations. Biological mechanisms of any kind cannot even be identified with confidence, or understood, until, at the least, reasonable inferences have bee