Fertile Feelings Lead to Wandering Eyes? Theories on why wives cheat

By: Dr. Eric Sabo

While scientists have not discovered an excuse for infidelity, they can at least offer an explanation for why some women are inclined to cheat: their fertility cycle.

In a recent study, researchers found that women were more likely to flirt with men when their chance for getting pregnant was at its highest. The handsomest of the bunch, as always, have little to worry about. The urge to be unfaithful was particularly documented by women who rated their partners low in "sexual attractiveness relative to investment attractiveness." In other words, the average boyfriend or husband is nice to have at home, but the guy across the bar looks better.

Dr. Martie Haselton, the lead author of the study, says that such desires may seem shallow and intellectually insulting, yet they are well intended and crafted through thousands of generations to foster the continuation of a strong genetic lineage. "Women can't “see” a man's genetic make up." says Haselton. "So, we are conditioned to take our hints from the physical attributes which are evident to us."

Men eternally claim they cannot understand women.  They may be well founded in their confusion, since it would appear that women do not themselves recognize the fact that they see men as a candidate for one of two very distinct categories, and treat them differently based on this subconscious classification. 

The first is as a potential long-term mate.  This individual demonstrates those characteristics often touted for a good husband, i.e., emotionally supportive, empathic, sensitive, protective and a good provider.  This is the man that a woman would be inclined to marry or partner with on a long-term basis. 

The second category is men that a woman would consider mating with.  Contrary to every socially and culturally engineered tradition, custom, rule or law, this is often NOT the same person that a woman has partnered with.  

Indeed, the characteristics of these two classes of men often are in conflict with one another.  The man that is a stable provider, husband and father is usually not the physically perfect specimen.  Similarly, the strong, physically fit, ruggedly handsome man often has his pick of willing short-term partners.  This type of man can be predisposed to a wandering lifestyle and thus not a reliable protector or provider of a woman and her offspring.  These two categories are often characterized as intellectuals vs. “bad boys” in today’s society.

Therefore, a woman may fall in love with the nerdy type, but her reproductive urges favor the masculine and attractive, regardless of whom she may partner with.  "Women have a biology that can lead them to stray, especially at certain times more than others." says Haselton. These urges served a purpose in ancient times, when a man's scruffy good looks and fit physique conferred an evolutionary advantage to a woman who wanted the healthiest, strongest offspring possible.

For the study, which was published in the journal Hormones and Behavior, Haselton had college aged women fill out a daily diary of their sexual interests and feelings. The majority of them had a boyfriend or husband. When the women neared their time of ovulation, they reported feeling more attractive and more interested in going out to meet men, even if they were already in a relationship.  Flirting increased noticably, much to the dismay of their partners.  As a result, men were more likely to become jealous and possessive during their girlfriend's peak reproductive days. The more unattractive guys were on guard all the time, especially if the women they were dating were seen as better looking than them.

Haselton says that some women are clearly slipping past their protective mates. Depending on the source and nationality, it is estimated that four to eleven percent of all pregnancies are the result of couplings between the female and a partner other than her designated. 

"Although women definitely cheat, men also have documented and logically based reasons for cheating" she says.  After five million years of evolution, no one can expect men to change in little more than 10,000 years. Simply put; men have the built-in desire to spread their seed to as many acceptable companions as possible. It is simply survival of the species: within nature, the male mates with numerous females in order to ensure the survival of the species through production of offspring. The practice of infidelity can be seen throughout the world and, for the most part, is accepted as a way of life despite the fact that many prefer to construct an artificial, socially engineered system to suppress this urge through the declaration of cheating as morally unethical.   

It is well known that for certain men cheating comes easily and with few feelings of guilt. In some cultures it is widely accepted. 

But don't start grabbing your crotch and spitting just yet; similar to the needs of men, women also have a biological urge to cheat. During ovulation, it is instinctive for them to shift into the huntress mode, seeking out the best males to impregnate them.  Realistically, in today’s culture, this urge manifests itself into actions which are largely muted, and more typically result in a heightened state of approachability and receptiveness.

Biologically speaking, when women ovulate, their bodies respond to their evolutionary conditioning, resulting in behavioral patterns intended to improve their odd of becoming impregnated by the best men available, namely those that are attractive, physically fit, strong and healthy.  This is often the dominant, or “Alpha” male of her given social circle, and is subject to the individual’s interpretation of what is attractive.  So there is still ample latitude for personal preference in the selection process. 

"Evolutionary psychologists tell us that married women are most likely to cheat on their husbands with a perceived Alpha male during that portion of her cycle when she's approaching ovulation, with the day of ovulation being the greatest risk. This is a natural response to a female's evolutionary desire to conceive children from the strongest, healthiest male available. 

While her husband may be a good provider and create a stable home environment for raising her children, a woman is instinctively compelled to conceive with the most physically appealing male.  Ironically, the extended lengths of monogamous relationships in today's society may reinforce this compulsion, as monotony can erode her perceived value of the husband in direct proportion to the increase in the appeal she perceives in the more attractive male.  

The onset of ovulation has an additional, markedly interesting offsetting effect, that being the greater risk of sub-optimal matings and resultant conception with an inferior male.  Immediately prior to and during ovulation, women demonstrated a marked increase in their lack of tolerance for men they did not consider as a potential short-term mate.  Surprisingly, this often included their current, long-term partner or husband.  Some data revealed that women became more likely to actively shun sexual advances from her husband, or fake orgasms to shorten the mating experience, and supposedly reduce the likelihood of impregnation.

Certain studies have revealed that as much as eighty percent (80%) of the entire female population, if given the choice based on physical preferences alone and without any consequences, would choose to conceive with only a select seven percent (7%) of the entire male population.  Furthermore, paternity test results, while varying from nation to nation, have indicated that somewhere between four percent (4%) and eleven percent (11%) of all husbands or men in otherwise committed relationships are not the true biological fathers of the children they are raising. 

Multiple lovers have other uses too. The anthropologist Sarah Blaffer Hardy has theorized that women copulate with more than one man to leave several men under the impression that they might be the father of particular offspring

In "Why Women Have Affairs" the author discusses many possible reasons regarding female infidelity.  Buss presents the hypothesis of mate insurance by our ancestral mothers.  He questions whether it was possible for a women to have relied solely on a single man to provide for her and her children in an era when life was a daily struggle for survival. 

Abandonment or death made it too risky for a woman to rely on one man.  The solution would be to cultivate partners as a backup mates.  The backup mate can serve many functions when the regular mate is not around.  By consenting to sexual 'favors' with another man, a woman greatly increases the possibility of a future return in material resources in the case that her regular mate could not provide sufficient resources.  Under such circumstances, women would choose backup partners based on their ability and willingness to provide resources and protection when necessary. 

Another potential theory of female infidelity is "trading up".  In this case, affairs could be used to evaluate potential husbands that may have 'better' qualities than the current mate.  There are several ancestral conditions that set foundation for this behavior.  For example, a woman's partner may decline in value due to disease or injury, or he may become abusive.  Also, a woman's value may have increased due to certain acquired skills or gained alliances. 

Lastly, due to nomadic lifestyles, contact with a new tribe may have exposed her to more desirable partners.  One critical quality for 'trading up' is a woman's own perception of her personal 'value' in the mating market.  In other words, having an affair can boost a woman's self-esteem, perception of her physical attractiveness, and sexuality.  If she has increased  confidence gained by having an affair, than the chances of her leaving her current mate for a better one are increased.  Moreover, in recent studies it was found that this increased confidence and self-esteem were rated by women who have affairs, as one of the most direct, beneficial results of having an affair. 

The importance of a woman's sexual gratification with an affair partner was further explored due in part to a theory called "sperm retention".  Proposed by two British biologists, this theory is better understood when the broader theory of sperm competition is introduced.  Sperm competition occurs when sperm from different men occupy a woman's reproductive tract simultaneously.  Although a female's egg is viable for only 12 to 24 hours after ovulation, sperm can remain viable for up to four days.  Therefore, if a woman has sex with two different men within days of each other, she activates a competitive race between the two different sperm, enjoying conception from the more successful of the two. 

Both male and female physiology and passions have evolved to the demands of this reproductive competition.  Evidence for this is provided in similar studies conducted in many countries regarding the rate of paternal discrepancy.  In such studies, roughly ten percent of children had biological fathers different from those whom they believed to be their legitimate fathers.  With these statistics, it is clear that women sometimes conceive and bear children from men other than their husbands and have probably done so throughout our ancestral history. 

Women have developed adaptive strategies to take advantage of their evolved physiology .  Human females are one of the few mammals that do not give any outward signs of ovulation.  According to Baker, women's concealed ovulation is among the major weapons women have evolved in order to 'shop around' for superior genes for their children.  With concealed ovulation women make it difficult for their regular mate to guard them during their most fertile time of the month.  Consequently, concealed ovulation sets the stage for sperm competition by giving women the opportunity to be fertilized by men of their own choosing with their regular mate being unaware.  In fact, the Calahonda study found that 37% of female participants who spent two weeks or more away from their partners participated in affairs.  Although this percentage is considered statistically high, the low risk of discovery due to the great distance apart was documented to contribute to this high rate of infidelity. 

            One of the most startling findings from these studies of sperm competition focused on a woman's sexual orgasm.  An orgasm is a factor most closely linked with a woman's sexual satisfaction.  Remarkably, women have more 'high sperm retention' orgasms with their affair partners than with their regular partner!  (As noted by the amount of sperm collected after intercourse).  This idea coincides with the fact that most women report sexual gratification as an essential ingredient in short-term extramarital affairs.  Moreover, women seem to time their sexual encounters with their affair partners to coincide more closely with their time of ovulation. 

          It was widely thought that female orgasms lacked an evolutionary function.  This idea is changing.  Sexual gratification from an affair partner and elevating self-esteem (due to the fact that more than one man found her attractive).  These rewards included sexual experimentation, more sexual orgasms, and receiving oral sex, which their regular partners may not provide. 

Short-term sexual strategists perceived these rewards to be more beneficial than monogamous women did.  The more promiscuous women were well aware of their sex` appeal and seemed capitalize on their sexuality by using multiple partners to gain status, material goods, and a wider pool of potential mates. 

The question remains, why do some women engage in a monogamous strategy while others opt for multiple partners?  One possibility is that casual strategists possess more abundant sexual assets that allow them to be more successful in reaping the various benefits from a short-term strategy.  Accordingly, a woman with less sexual appeal may be more limited in her success regarding extramarital affairs.  This explanation suggests that casual strategists should be viewed as more 'sexy' than a monogamous woman, but not necessarily more physically attractive. 

 
With all the potential benefits a woman can gain through affairs, it is puzzling that most women do not have affairs.  To understand this behavior, we could discuss the costs of infidelity.  The benefits from a woman's affair are offset by the risk of losing her regular mate.  Each woman's decision to stay or stray hinges on cost-benefit calculations based on the consequences of being discovered.  Nonetheless, it would appear that some percentage of married women do cheat on their spouses, and most of that activity peaks at or near the time of their ovulation.