While the old adage that “beauty is in the eye of the beholder” is very true, any examination of cultures around the world will reveal a pattern in mating selection that seems to rise above individual ideals of beauty and attraction. This pattern is so strongly presented and occurs with such frequency that it seems almost natural. And in fact, there is a biological basis for it.

The pattern that is seen is that of an older gentleman of status and resources pairing with a younger, physically fit woman. This is the classic “May-December” relationship and the biological basis for it underpins the differences between the sexes when it comes to what is attractive and also the apparently different attitude toward monogamy.

So what exactly is this biological basis?

Put simply. It has to do with the difference between men and women when it comes to procreation. Think about it. How much minimum investment does a man have to make in order to successfully procreate? The answer is not much at all--for some of you, only a matter of minutes. :-) After fertilization, there is no further commitment of resources that is absolutely required for success.

Conversely, how much minimum investment does a woman have to make in order to procreate? First, there is the gestation period itself. For nine months more or less she will undergo major physical, hormonal and emotional changes. Then, after birth, if the child is to live (and reach successful reproductive age itself), she must feed and care for it for many more years. So for the woman the minimum investment is very significant indeed.

It is these inherent and fundamental differences that influence our views of attraction. This is true even if we are not consciously considering procreation or even if we are adverse to the idea. That is because these differences are understood by our brains and hardwired into the background human operating system. Like any other genetic predisposition, we can exercise free choice but we can’t ignore it entirely.

How exactly do these biological differences influence what men and women find attractive?

As for men, because a man’s minimum investment in procreation is relatively low, the primary concerns in terms of a potential mate are whether she will be fertile and a good caregiver. For the most part then, in today’s modern societies the aspect of “fertility” is best characterized by youthfulness and good physical health. Further attributes of a woman pertaining to the ability to be a good caregiver such as industriousness, tenderness and resourcefulness will also be highly prized by males. Thus the man in summary typically desires a young beautiful woman.

On the issue of monogamy, since fertility is not guaranteed even when these prerequisites are met, a man’s biological best bet is covered through mating frequency and variety. So this biological influence in combination with high testosterone levels (testosterone is the main hormone responsible for “sex drive”) results in the innate urge for men to seek out multiple partners and to be less discriminating when it comes to sex with potential partners.

Now contrast this with females.

As mentioned, the female’s biological investment is very great. She is going to need someone with the tangible material goods resources to support her during the pregnancy and afterwards (especially for the portion of time when she would be unable to work.) Therefore, rather than attributes like beauty and athletic ability, the primary concern will be whether the man has the appropriate amount of tangible material goods resources—or at least possesses qualities that are likely to lead to the accumulation of these.

Typically among the available pool and especially in contrast to men of her own age group, the most desirable men then possessing this biologically attractive attribute are going to be older males—who have obtained status and tangible material goods.

As for “commitment”, a woman is going to highly prefer a gentleman that gives every indication that he is willing to devote the body of his entire tangible material goods resources to her and her future offspring. When a woman speaks of commitment this is EXACTLY what she is talking about—even if she can’t articulate it in this fashion.

As for monogamy and most women’s general disapproval of anything else, it should now be obvious that unless the man’s total pool of resources is large enough to adequately support her and the second woman (think about Hugh Hefner), she is going to find it extremely threatening that you might potentially or actually be diverting some of the resources to the sustaining of someone else. This is in fact why many more women than men are willing to overlook or forgive their partner’s casual sexual encounter with another person, provided that there is not an emotional connection or a squandering of material resources involved.

It is interesting to note that of the approximately 1,154 societies that have existed, past or present, 980 allow polygamy. But observe that virtually all of these polygamist societies allow it only in accord with strict rules that provide that the multiple wives are completely provided for in a material way. (That is why it is usually only the “chief” or “sheik” or head clansman that is permitted to enjoy this state.) It is unlikely that the women in those societies would tolerate it if the situation were otherwise.

Yes, women are very choosey. Sometimes it even seems like they are even “shallower” than men. But they have to be. They have to be selective about the man that is going to be half of the gene machine.

Of course, fortunately for all of us, biology is not destiny. After all studies have found a genetic predisposition towards alcoholism in some persons and we don’t say to such ones: “Hey, have a drink, it’s who you are.”

Likewise, while we can’t totally escape the influence that the biological basis of attraction exerts upon us, we can and generally do modify our requirements, desires and behaviour. For a number of reasons, both practical and even moral or religious, we conform our conduct in a fashion acceptable to our society.

Yet, understanding even embracing the biological basis of attraction, helps us to explain why we do what we do and who we are. It helps us to be less cynical about women who want a man with “good” genes and a healthy bank account and less judgmental about a man that is highly attracted to a “pretty young thing.” Although, while women can easily see the former point, they will often never be happy about admitting that it is not only acceptable but apparently biologically advisable for men to lust after younger women. This is for obvious reasons and because men too often put away the wife of their youth and trade her in for a younger model. (Not a practice that I approve of by the way.)

Nevertheless, should you ever find yourself trying to justify your own “May-December” relationship or puzzling over why THAT girl is with THAT guy, there is no need to wonder or make excuses. Just smile and say: “Mother Nature. She’s a beautiful thing.”