Childhood familiarity theory. Also called as westermarck effect. Proposed by Edward westermarck in 1891.
Israel Kibbutz and Chinese sim-pua marriage (where children raised as brother (son) and sister (adopted girl) are married in adulthood which leads to high divorce rate) is cited as an example for this theory.
This theory is counted by studies of
Zikri baluch in Pakistan - Pastner 1986.
Arapesh; The Chukchee - Leavitt 2007
There is still debate about biological and cultural basis of incest taboo.
Confirm Sir about conclusion. Any recent development ?