When Hollywood stars or politicians have extramarital affairs, the whole world rumbles. However, were we to look into human biology, anthropology and sociology, we would see that the monogamous human comes off as a very weird notion. Monogamy was invented for a sense of order and as to make a profitable investment, not necessarily because it's natural - or so warn many researchers, showing that both social and sexual monogamy in humans is not a natural state.
Most primitive human societies and many evolved societies have been practicing the harem system. Monogamy only emerged as hunter-gatherer societies took up agriculture and settled in houses, which prompted the social roles of men and women to become more fixed.
Humans display a higher paternal investment than most other primates. The committed partnership between a man and a woman may have evolved just to raise the human offspring throughout the entire duration of a long childhood. Still, it is clear that males stand less to lose than females by having extramarital sex. Women, on the other hand, would lose resources and support to raise their newborn to adulthood, while female promiscuity clearly does not help increase the welfare of her children.
A strictly monogamous animal mates only within the pair. For example, in the case of geese, albatrosses or some parrots, the death of a partner totally compromises mating for the other, for that season or for it entire life in some cases. With all that, strictly sexually monogamous species are almost non-existent. In most mammals we can only talk about social monogamy since they pair up to mate and to raise offspring, but still have flings: in Arctic foxes, 25 % of the litters are not fathered by the male of the pair. Having offspring from multiple fathers increases genetic variation in the offspring, thus their survival.
Both males and females attempt to increase their evolutionary progress by seeking out high-quality mates. Evolutionary psychologists suggested that men are more likely to have extramarital sex, because of the male's urge to "spread genes" through sperm.
Family and cheating
"Although marriage implies multiple obligations, the obligation to be sexually faithful to one's spouse seems to carry the most weight. In fact, infidelity is the marital problem most likely to lead to divorce," Paul Amato, a professor of sociology at Penn State told LiveScience.
Psychologists show that men are driven to cheat primarily by the lure of sex, while women because of emotional neglect and emotional intimacy. In our modern society, the percentage of cheating women is rising, because of the ease to travel to places where they can remain anonymous and their increasing economical power, which makes them less dependent on their husbands.
A 1994 study showed that throughout their lifetime, 18% of women and 24% of men cheated on their spouse. Still, a 2006 survey showed that about 90% of the Americans view extramarital sex as intolerable.
Both genders react similarly to cheating, feeling rage, sadness, humiliation, and depression. Nevertheless, the biological evolutionary factors make men give more importance to the sexual side of infidelity, while women rather focus on the emotional side. Come to think of it, this is only normal: a cheating woman might force her husband to raise kids that are not his, thus who do not carry his genes. On the other hand, the wife is 100% the mother of the kids, and a husband falling in love with another woman may redirect the resources of the household, necessary for raising the kids, towards another direction.
This explains why women are more likely to forgive an affair not involving emotions, while also being more prone to forgive a husband that had been busted in the act. On the other hand, even if men are not that concerned about the emotional connection between their wives and a lover, they still dislike their wives fooling around. Women also tend to take the family into account when pondering the possibility of a split.
"Women are more likely to take into account their children, their economics, their general survival. Men are just crushed or upset about what happened to them. They won't think as quickly about their children as the first or second issue; but they will eventually consider that," Pepper Schwartz, a professor of sociology at the University of Washington in Seattle, told LiveScience.
Men are generally more affected by stressful reactions and perceive cheating as something more directed to him and his manhood, rather than to the relationship itself. "Wives are also less likely to consider divorce if they are economically dependent on their husbands, have children or hold strong religious views," Amato said. "Nevertheless, most wives at least consider the option of divorce," said Amato.
The most severe effect of cheating is the loss of trust. Fixing the damage inflicted upon the relationship, if such a thing is possible in the first place, may take a long period of time. "After the incident comes to light, husbands as well as wives are less happy with their marriages, report more marital conflict, experience elevated levels of psychological distress and increase their thoughts of divorce. Many spouses never fully recover from their feelings of betrayal and anger, even if they stay together. Counseling can help, however, and some couples eventually manage to repair their relationships. Re-establishing trust takes time, but if both spouses sincerely want the marriage to continue and are willing to work on it, then it is possible to have a healthy relationship again." Amato explained.
A recent research signaled that most couples remain together after one of the partners has cheated on the other, thus indicating that people can and do realize they really have something to protect.
Therapists even detect 3 stages of the emotions following cheating. "Roller-coaster" is the stage when the person experiences strong contradictory feelings, from anger and self-blame to introspection and positive evaluation of the relationship. During the "moratorium", the cheated-on spouse attempts to analyze the cheating event, going deep into the details of the affair, and at the same time interrupting physical and emotional contact with the cheater and looking for help in others. The "trust-building stage" can follow, but only for those who want to stay together and fix their marriage.