Olfactory sexual inhibition and the westermarck effect

The Westermarck effect (sexual inhibition among individuals raised together) is argued to be mediated olfactorily. Various animals, including humans, distinguish among individuals by scent (significantly determined by MHC genotype), and some avoid cosocialized associates on this basis. Possible models of olfactory mechanisms in humans are evaluated. Evidence suggests aversions develop during an early sensitizing period, attach to persons as much as to their scents, and are more powerful among females than among males. Adult to child aversions may develop similarly, but more likely result from stimulus generalization. This hypothesis accords with current evidence and yields testable predictions (e.g., anosmia will prevent inhibition) that, should they be supported, will conclusively ground the Westermarck effect in a biological mechanism. A version of this paper was originally presented at the 92nd annual meeting of the American Sociological Association in Toronto, Canada. Mark A. Schneider is a sociologist of science and author of “Sacredness, Status and Bodily Violation” (Body and Society, 1996) as well as Culture and Enchantment (Chicago, 1993). Lewellyn Hendrix has written extensively on families in cross-cultural perspective and is the author of Illegitimacy and Social Structures (Bergin and Garvey, 1996). They recently coauthored “Assumptions on Sex and Society in the Biosocial Theory of Incest” (Cross-Cultural Research, 1999).