Intergenerational incest aversion: self-reported sexual arousal and disgust to hypothetical sexual contact with family members

Publication date: Available online 22 June 2018Source: Evolution and Human BehaviorAuthor(s): Paula Kresanov, Jennifer Kotler, Michael Seto, Debra Lieberman, Pekka Santtila, Jan AntfolkAbstractThe biological costs of inbreeding are expected to have shaped human incest aversion. These costs depend on biological sex, relatedness, and age. Whereas previous studies have focused on investigating how these factors modulate incest aversion in siblings and cousins—family members of the same generation—here we examined relatives of different generations. In a population-based sample, 2499 respondents reported reactions to imagined sexual behaviors with either a biological child or parent, a niece/nephew or aunt/uncle, or a stepchild or stepparent; these responses were compared to reactions to imagined sexual behaviors involving a friend's child or parent. Replicating prior results, women report stronger incest aversions than do men. We extend previous findings by showing that incest aversions tended to be stronger between close (vs. more distant) intergenerational relatives. Indeed, for biological relatives, decreased degree of relatedness was associated with decreased incest aversion, and for biological relatives, the certainty in relatedness was also positively associated with incest aversion. As expected, age modulated sexual aversion for unrelated, but not related, target individuals. Sexual aversions towards step-relatives did not differ from sexual aversions to biological re...

Source: Evolution and Human Behavior - July 10, 2018 Category: Psychiatry & Psychology Source Type: research