Incest is human sexual activity between family members or close relatives. This typically includes sexual activity between people in consanguinity, and sometimes those related by lineage. It is forbidden and considered immoral in most societies, and can lead to an increased risk of genetic disorders in children in case of pregnancy.
Egyptian king Tutankhamun married his half-sister Ankhesenamun.
Maya king Shield Jaguar II with his aunt-wife, Lady Xoc AD 709
Charles II of Spain was born physically disabled, likely due to centuries of inbreeding in the House of Habsburg, and suffered a particularly pronounced case of Habsburg jaw
Maximilian II, Holy Roman Emperor married his first cousin Maria of Spain.
In anthropology, kinship is the web of social relationships that form an important part of the lives of all humans in all societies, although its exact meanings even within this discipline are often debated. Anthropologist Robin Fox says that the study of kinship is the study of what humans do with these basic facts of life – mating, gestation, parenthood, socialization, siblingship etc. Human society is unique, he argues, in that we are "working with the same raw material as exists in the animal world, but [we] can conceptualize and categorize it to serve social ends." These social ends include the socialization of children and the formation of basic economic, political and religious groups.
A multi-generational extended family in Chaghcharan, Ghor Province, Afghanistan.
A multi-generational extended family of Eastern Orthodox priest in Jerusalem, c. 1893
An illustration of the bi-relational and tri-relational senses of nakurrng in Bininj Kunwok.
