Do humans reason about cultural group identities as if they were fixed? Participants must decide the group identity of a hypothetical child who is born to parents from one group, but raised by parents from a different group

Do humans reason about cultural group identities as if they were fixed? Cristina Moya, Richard McElreath, Joseph Henrich. Human Behavior and Evolution Society 31st annual meeting. Boston 2019. http://tiny.cc/aa1w6y

Abstract: In some societies people expect children will inherit social group identities from their birth parents, even in their absence. This belief in intergenerationally inherited and fixed identities is puzzling given the importance of socialization for membership in most cultural groups. We meta-analyse results from over 3000 decisions made by children and adults from different societies in switched-at-birth vignette studies. In these, participants must decide the group identity of a hypothetical child who is born to parents from one group, but raised by parents from a different group. We compare these to studies where people were asked about the species identities of animals in a similar scenario. We find that across development beliefs about species identity beliefs homogenize towards notions of identity being stable, whereas social identity beliefs diversify and tend to move towards beliefs that identities are not fixed at birth. This diversity of beliefs is patterned, with groups marked by status differences being associated with more fixed notions about identity. Importantly, phenotypic differences are not particularly likely to trigger essentialist inferences in children or adults. These patterns suggest that the cognitive mechanisms used for reasoning about human cultural groups are qualitatively different than those used for reasoning about species.