evolutionary psychology the subfield of psychology that explains human behavior and cultural arrangements by employing evolutionary biology and cognitive psychology to discover, catalog, and analyze psychological mechanisms. Human minds allegedly possess many innate, special-purpose, domain-specific psychological mechanisms (modules) whose development requires minimal input and whose operations are context-sensitive, mostly automatic, and independent of one another and of general intelligence. (Disagreements persist about the functional isolation and innateness of these modules.) Some evolutionary psychologists compare the mind – with its specialized modules – to a Swiss army knife. Different modules substantially constrain behavior and cognition associated with language, sociality, face recognition, and so on. Evolutionary psychologists emphasize that psychological phenomena reflect the influence of biological evolution. These modules and associated behavior patterns assumed their forms during the Pleistocene. An evolutionary perspective identifies adaptive problems and features of the Pleistocene environment that constrained possible solutions. Adaptive problems often have cognitive dimensions. For example, an evolutionary imperative to aid kin presumes the ability to detect kin. Evolutionary psychologists propose models to meet the requisite cognitive demands. Plausible models should produce adaptive behaviors and avoid maladaptive ones – e.g., generating too many false positives when identifying kin. Experimental psychological evidence and social scientific field observations aid assessment of these proposals. These modules have changed little. Modern humans manage with primitive hunter-gatherers’ cognitive equipment amid the rapid cultural change that equipment produces. The pace of that change outstrips the ability of biological evolution to keep up. Evolutionary psychologists hold, consequently, that: (1) contrary to sociobiology, which appeals to biological evolution directly, exclusively evolutionary explanations of human behavior will not suffice; (2) contrary to theories of cultural evolution, which appeal to biological evolution analogically, it is at least possible that no cultural arrangement has ever been adaptive; and (3) contrary to social scientists, who appeal to some general conception of learning or socialization to explain cultural transmission, specialized psychological mechanisms contribute substantially to that process. See also COGNITIVE SCIENCE , DARWINISM, MODULARITY, PHILOSOPHY OF THE SOCIAL SCIENCES , SOCIAL BIOLOGY. R.N.Mc.