Evolutionary psychology is a theoretical approach in the social and natural sciences that examines psychological structure from a modern evolutionary perspective. It seeks to identify which human psychological traits are evolved adaptations – that is, the functional products of natural selection or sexual selection in human evolution. Adaptationist thinking about physiological mechanisms, such as the heart, lungs, and immune system, is common in evolutionary biology. Some evolutionary psychologists apply the same thinking to psychology, arguing that the modularity of mind is similar to that of the body and with different modular adaptations serving different functions. Evolutionary psychologists argue that much of human behavior is the output of psychological adaptations that evolved to solve recurrent problems in human ancestral environments.[1] Evolutionary psychology is not simply a subdiscipline of psychology but its evolutionary theory can provide a foundational, metatheoretical framework that integrates the entire field of psychology in the same way evolutionary biology has for biology.[2][3][4] Evolutionary psychologists hold that behaviors or traits that occur universally in all cultures are good candidates for evolutionary adaptations[5] including the abilities to infer others' emotions, discern kin from non-kin, identify and prefer healthier mates, and cooperate with others. They report successful tests of theoretical predictions related to such topics as infanticide, intelligence, marriage patterns, promiscuity, perception of beauty, bride price, and parental investment.[6] The theories and findings of evolutionary psychology have applications in many fields, including economics, environment, health, law, management, psychiatry, politics, and literature.[7][8] Criticism of evolutionary psychology involves questions of testability, cognitive and evolutionary assumptions (such as modular functioning of the brain, and large uncertainty about the ancestral environment), importance of non-genetic and non-adaptive explanations, as well as political and ethical issues due to interpretations of research results.[9][10]