The sociobiological theory of incest

The sociobiological theory of incest

Titre de l'ensemble: Incest

This chapter examines the socio-biological theory of incest. Incest is a special case of mating between relatives, called inbreeding. Every behavior can be advantageous or disadvantageous to the individual's genetic fitness. Close inbreeding is usually harmful in higher organisms. Therefore, it is expected that through evolution close inbreeding will somehow be eliminated or rendered rare in higher organisms, including humans. The co-evolutionary process creates the human universal of incest regulations (inhibitions, preventions, and prohibitions) that becomes central in human social life. This centrality assures its persistence mainly because, once established, the universal has very important secondary functions. As a technical term, inbreeding is reserved for cases in which discernible traces can be followed back to common ancestors within two to three generations. Inbreeding increases homozygosity and hence, the chance that a deleterious recessive gene will manifest itself in the phenotype. Incest, a specific case of reproduction, underwent evolutionary change.