Inclusive fitness in humans

Inclusive fitness in humans is the application of inclusive fitness theory to human social behaviour, relationships and cooperation.

Inclusive fitness theory (and the related kin selection theory) are general theories in evolutionary biology that propose a method to understand the evolution of social behaviours in organisms. While various ideas related to these theories have been influential in the study of the social behaviour of non-human organisms, their application to human behaviour has been debated.

Inclusive fitness theory is broadly understood to describe a statistical criterion by which social traits can evolve to become widespread in a population of organisms. However, beyond this some scientists have interpreted the theory to make predictions about how the expression of social behavior is mediated in both humans and other animals – typically that genetic relatedness determines the expression of social behaviour. Other biologists and anthropologists maintain that beyond its statistical evolutionary relevance the theory does not necessarily imply that genetic relatedness per se determines the expression of social behavior in organisms. Instead, the expression of social behavior may be mediated by correlated conditions, such as shared location, shared rearing environment, familiarity or other contextual cues which correlate with shared genetic relatedness, thus meeting the statistical evolutionary criteria without being deterministic. While the former position still attracts controversy, the latter position has a better empirical fit with anthropological data about human kinship practices, and is accepted by cultural anthropologists.