The Westermarck effect, also known as reverse sexual imprinting, is a psychological hypothesis that people tend not to be attracted to peers with whom they lived like siblings before age six. This hypothesis was first proposed by Finnish anthropologist

Edvard Westermarck Edvard Alexander Westermarck (Helsinki, 20 November 1862 – Tenala, 3 September 1939) was a Finnish philosopher and sociologist. Among other subjects, he studied exogamy and the incest taboo. Biography Westermarck was born in 1862 in a ...

in his book '' The History of Human Marriage'' (1891) as one explanation for the

incest taboo An incest taboo is any cultural rule or norm that prohibits sexual relations between certain members of the same family, mainly between individuals related by blood. All human cultures have norms that exclude certain close relatives from ...

Research since Westermarck

The Westermarck effect has achieved some empirical support.''Inbreeding, Incest, and the Incest Taboo: The State of Knowledge at the Turn of the Century'', Arthur P. Wolf and William H. Durham (Editors), Stanford University Press, 2004, . Introduction Proponents point to evidence from the Israeli

kibbutz A kibbutz ( he, קִבּוּץ / , lit. "gathering, clustering"; plural: kibbutzim / ) is an intentional community in Israel that was traditionally based on agriculture. The first kibbutz, established in 1909, was Degania. Today, farming h ...

system, from the Chinese

Shim-pua marriage Tongyangxi (), also known as Shim-pua marriage in Min Nan dialects (; and in phonetic Hokkien transcription using Chinese characters: 新婦仔), was a tradition of arranged marriage dating back to pre-modern China, in which a family would ado ...

customs, and from closely related families. In the case of the Israeli

im (collective farms), children were reared somewhat communally in peer groups, based on age, not biological relations. A study of the marriage patterns of these children later in life revealed that out of the nearly 3,000 marriages that occurred across the kibbutz system, only 14 were between children from the same peer group. Of those 14, none had been reared together during the first six years of life. This result suggests that the Westermarck effect operates during the period from birth to the age of six. In Shim-pua marriages, a girl would be adopted into a family as the future wife of a son, often an infant at that time. These marriages often failed, as would be expected according to the Westermarck hypothesis. Studies show that cousin-marriage in Lebanon has a lower success rate if the cousins were raised in sibling-like conditions, first-cousin unions being more successful in Pakistan if there was a substantial age difference, as well as reduced marital appeal for cousins who grew up sleeping in the same room in Morocco. Evidence also indicates that siblings separated for extended periods of time since childhood were more likely to report having engaged in sexual activity with one another.

Criticism

Eran Shor and Dalit Simchai revisited the kibbutzim results and found sexual attraction where it hadn't been acted on. They conclude that any innate aversion needs to be backed up by social pressures and norms.

Research since Westermarck

Criticism

See also

References

Further reading