The Westermarck Effect: The Lack Of Desire For Childhood Friends
Many people are interested in knowing what characteristics and behavioral styles enhance personal attractiveness, but fewer also try to know things about the factors that kill any possibility of attraction in the bud.
That is why it is not surprising that so little is known about the Westermarck effect a hypothetical psychological phenomenon according to which human beings are predisposed to not feel sexual desire towards the people with whom we interact continuously during our early childhood, regardless of whether they are related or not.
Why might this curious trend occur? The explanation proposals that many researchers are considering to resolve the mystery of the Westermarck effect have to do with the phenomenon of incest
In all current societies there are taboosthat is to say, behaviors and ideas that are not socially accepted for reasons that have to do, at least in part, with the dominant morality or the religious beliefs associated with that culture. It is easy to find drawbacks to some of these taboos, such as intentional homicide or cannibalism, from a pragmatic point of view, because if they become widespread, they could destabilize the social order and produce an escalation of violence, among other things.
However, there is a universal taboo that we can find in practically all cultures throughout history but whose prohibition is difficult to rationally justify: the incest.
Taking this into account, Many researchers have wondered what is the origin of the omnipresent rejection that generates everything related to relationships between family members Among all the hypotheses, there is one that has gained strength in recent decades and is based on a psychological effect based on the combination between genetic innatism and learned behaviors. This is the Westermarck effect hypothesis.
question of probabilities
Edvard Alexander Westermarck was a Finnish anthropologist born in the mid-19th century known for his theories about marriage, exogamy and incest. Concerning the latter, Westermarck proposed the idea that incest avoidance is the product of natural selection For him, avoiding reproduction between relatives would be part of an adaptive mechanism that we carry in our genes and that would have spread among the population due to the advantageous nature of this behavior in evolutionary terms.
Since offspring resulting from incest can have serious health problems, selection would have carved into our genetics a mechanism for us to feel aversion to it, which in itself would be an adaptive advantage.
Ultimately, Westermarck believed that natural selection has shaped the sexual tendencies of our entire species by preventing relationships between close relatives.
Suppressing sexual attraction to avoid incest
But how would natural selection promote incest-avoidance behaviors? After all, there is no trait by which we can recognize brothers and sisters at a glance. According to Westermarck, evolution has decided to use statistics to create a mechanism of aversion between family members. Since people who see each other daily during the first years of life and belong to the same environment are very likely to be related, the criterion used to suppress sexual attraction is the existence or not of proximity during childhood.
This predisposition to not feel attraction to the people with whom we come into contact periodically during the first moments of our lives would be genetically based and would represent an evolutionary advantage; but, as a result of this, We would not have sexual interest in old childhood friends either
The anti-oedipus
To better understand the mechanism through which the Westermarck effect is articulated, it is useful to compare this hypothesis with the ideas about incest proposed by Sigmund Freud.
Freud identified the incest taboo as a social mechanism to repress sexual desire towards close relatives and thus make possible the “normal” functioning of society. The Oedipus complex would be, according to him, the way in which the subconscious takes this blow directed against the sexual inclinations of the individual from which it follows that the only thing that makes the practice of incest widespread is the existence of the taboo and the punishments associated with it.
The biological conception of the Westermarck effect, however, directly attacks what was proposed in the Oedipus complex , since in his explanation of the facts the taboo is not the cause of sexual rejection, but the consequence. This is what makes some evolutionary psychologists support the idea that it is evolution, rather than culture, that speaks through our mouths when we express our opinion about incest.
Some studies on the Westermarck effect
The Westermarck effect proposal is very old and has been buried by a barrage of criticism from anthropologists and psychologists who defend the important role of learned behaviors and cultural dynamics in sexuality. However, little by little it has been raising its head until accumulating enough evidence in its favor.
When talking about the evidence that reinforces Westermarck’s hypothesis, the first case that is usually mentioned is that of J. Sheper and his study on the populations residing in kibbutz (communes based on the socialist tradition) of Israel, in which many unrelated girls and boys are raised together. Although contacts between these children are constant and continue until they reach adulthood, Sheper concluded that The occasions on which these people have sexual relations are rare at some point in their lives, being much more likely to end up marrying others.
Other interesting examples
Since Sheper’s article was published, criticism has been made about the methodology used to measure sexual attraction without cultural or sociological factors interfering and, however, many other studies have also been published that reinforce the hypothesis of the Westermarck effect.
For example, research based on questionnaires given to the Moroccan population showed that the fact of having close and continuous contact with someone during early childhood (regardless of whether they are related or not) makes it much more likely that upon reaching adulthood they will feel aversion to the idea of ​​marrying this person.
Lack of attraction present even in ‘Westermarck marriages’
Furthermore, in cases where two people who have grown up together without sharing blood ties marry (for example, by adult imposition), They tend not to leave offspring due perhaps to lack of attraction This has been found in Taiwan, where there has traditionally been a custom among some families of letting the bride be raised in the house of the future husband (marriage Shim-pua).
The taboo is linked to continued coexistence
Evolutionary psychologist Debra Lieberman also helped reinforce the Westermarck effect hypothesis through a study in which she asked a series of people to fill out a questionnaire. This sheet contained questions about her family, and also presented a series of reprehensible actions such as drug use or homicide. The volunteers had to order according to the degree to which they thought they were bad, from most to least morally reprehensible, so that they were placed in a kind of ranking.
In the analysis of the data obtained, Lieberman found that the amount of time spent with a brother or sister during childhood positively correlated with the degree to which incest was condemned In fact, one could predict the extent to which a person would condemn incest just by looking at the degree of exposure to a sibling in childhood. Neither the attitude of the parents nor their degree of kinship with the brother or sister (adoptions were also taken into account) significantly affected the intensity of the rejection of this practice.
Many doubts to resolve
We still know very little about the Westermarck effect. It is unknown, first of all, whether it is a propensity that exists in all societies on the planet, and whether or not it is based on the existence of a partially genetic trait. Of course, It is also not known what genes could be involved in its functioning either and if it manifests differently in men and women.
The answers about the psychological and universal propensities typical of our species, as always, are long in coming. Only decades of continued research can bring to light these innate predispositions, buried in our body under thousands of years of adaptation to the environment.
Bibliographic references:
Spiro, M. E. (1958). Children of the Kibbutz. Cambridge: Harvard University Press. Cited in Antfolk, J., Karlsson, Bäckström, M. and Santtila, P. (2012). Disgust elicited by third-party incest: the roles of biological relatedness, co-residence, and family relationship. Evolution and Human Behavior, 33(3), pp. 217 – 223.
Talmon, Y. (1964). Mate selection on collective settlements. American Sociological Review, 29(4), pp. 491 – 508.
Walter, A. (1997). The evolutionary psychology of mate selection in Morocco. Human Nature, 8(2), pp. 113 – 137.
Westermarck, E. (1891). The history of human marriage. London: Macmillan. Cited in Antfolk, J., Karlsson, Bäckström, M. and Santtila, P. (2012). Disgust elicited by third-party incest: the roles of biological relatedness, co-residence, and family relationship. Evolution and Human Behavior, 33(3), pp. 217 – 223.
Wolf, A. (1970). Childhood Association and Sexual Attraction: A Further Test of the Westermarck Hypothesis. American Anthropologist, 72(3), pp. 503 -515.
