Cultural group selection

Cultural group selection is an explanatory model within cultural evolution of how cultural traits evolve according to the competitive advantage they bestow upon a group. This multidisciplinary approach to the question of human culture engages research from the fields of anthropology, behavioural economics, evolutionary biology, evolutionary game theory, sociology, and psychology.

While cultural norms are often beneficial to the individuals who hold them, they need not be.^[1] Norms can spread by cultural group selection when they are practiced within successful groups, and norms are more likely to spread from groups that are successful. But, for cultural group selection to occur, there must exist, between groups, cultural differences that when transmitted across time affect the persistence or proliferation of the groups.^[2] Cultural norms that provide these advantages will, in turn, lead to the displacement, absorption or even extinction of other, less successful cultural groups.^[3] However, game theoretic models suggest that if individuals are able to migrate between groups (which is common in small-scale societies), differences between groups should be difficult to maintain.^[4] Research in psychology reveals that humans have a particular set of traits, which include imitation, conformity, and in-group bias, that are capable of supporting the maintenance of these group differences over extended periods of time.

Cultural group selection gives a compelling explanation for how large-scale complex societies have formed.^[5] While altruistic behaviour such as kin selection and reciprocity can explain the behaviour of small social groups common in many species, it is unable to explain the large complex societies of unrelated, anonymous individuals that we see in the human species.^[4] However, one of the major distinctions between humans and other species is our reliance on social learning in acquiring behaviours.^[6] These instincts allow for the acquisition and persistence of culture.^[7] Through cultural group selection, culturally specific cooperative behaviour can evolve to support large societies.^[4] For example, in a study that spanned a variety of cultures, testing behaviour in Ultimatum, Dictator, and Third-party punishment games, it was found that standards of fairness and inclination to punish were correlated with both participation in world religions and market integration.^[8] This indicates how many of the behaviours necessary for complex societies are the result of cultural exposure rather than any evolution of our psychology.