The Rational Animal: How Evolution Made Us Smarter Than We Think

by Kenrick, Douglas T.

  Men’s preference for youthful and beautiful women is not limited to the patrons of strip clubs and escort services. Social scientists studying people’s mate preferences have found that men generally prefer and marry partners younger than themselves, whereas women are interested in somewhat older men. Researchers initially speculated that this difference was linked to gender roles perpetuated by American media. But that explanation did not hold up to careful examination. For starters, men’s attraction to younger women is in no way limited to American or even Western society. When Rich Keefe and Doug investigated singles ads and actual marriage ages around the world, including places that had never been exposed to American media, men everywhere preferred women in their early twenties. Even fifteen-year-old boys fantasized about college-age women, who are eighteen to twenty-two years old, despite the fact that the young guys are painfully aware that college women want nothing to do with them.

  Why are both older men and teenage boys around the world attracted to women in their early twenties? If you asked a man, he might simply say that women of this age have the most attractive features—a curvaceous figure combined with youthful hair and well-toned skin. But this explanation only provides a surface-level proximate reason. It does not address the deeper question of why the combination of features found in a woman of twenty-two is generally more attractive than the features found in a woman of forty-two, sixty-two, or eighty-two.

  From an evolutionary perspective, though, there is a clear reason—women in their early twenties are most fertile. Women at this age not only conceive more easily but also have many more childbearing years remaining. Even if a man says, “I don’t want children,” his brain is nevertheless wired to light up when he sees a woman whose smooth skin, youthful hair, and rounded hips signal fertility.

  The preference for youthful beauty can be seen most clearly in men with enough wealth and status to choose between many possible mates. Multimillionaire Donald Trump has been married three times, when he was thirty-one, forty-four, and fifty-four. He met each of his wives while she was in her twenties and married her shortly thereafter.

  King Henry VIII was first married at age seventeen to a woman in her early twenties. He married five other women over the next several decades of his life. His oldest wife, whom he married when he was fifty-one, was herself all of thirty-one on the day of the wedding (he had met her when she was still in her twenties).

  Male rulers throughout history, including Roman and Chinese emperors and Middle Eastern sultans, have frequently had hundreds of wives and concubines—and generally all of these men had a preference for young and beautiful virgins. Every year at Swaziland’s annual Reed Festival, tens of thousands of young maidens dance topless before King Mswati III, hoping to be chosen as his next wife. Rajinder Singh, the fabulously wealthy Sixth Maharajah of the state of Patiala in India, had 350 wives. There are clear evolutionary benefits to desiring to fornicate with so many young and fertile females. Ismael Ibn Sharif, who ruled Morocco at the turn of the eighteenth century and kept hundreds of wives, had over one thousand recorded children.

  The equation of youth + beauty = fertility is even more true in traditional societies than in the developed world. Rich Keefe and Doug found that the tendency for older men to marry younger women was more rather than less pronounced outside North America and Europe. Why? In the United States, Canada, and Europe, women tend to stay beautiful for many years longer than their counterparts in Third World societies, who begin having children earlier and have less access to adequate nutrition, health care, and beauty-enhancing consumer goods. In traditional societies, even Demi Moore and Jennifer Aniston would look their age.

  DESIGNING A MATE: HERS VERSUS HIS

  Thus far, our discussion of sex differences has been somewhat one-sided: women bear the children, which makes them selective in choosing partners; men expend energy and resources to gain access to women, especially when the women are young and fertile. But if a woman were buying a man, would she be shopping for the same features as a man seeks in a woman or for something different?

  Norm Li trained as an economist before earning a PhD in social psychology. He used his economics background to solve an important puzzle regarding men’s and women’s mate preferences. Some researchers had found big sex differences, with men and women saying they looked for very different characteristics in a mate. But others had found much smaller sex differences. The latter group accused the former of exaggerating the sex differences, arguing that men and women really want more or less the same thing in a mate.

  Li suspected that the question of sex differences and similarities had been ignoring a fundamental economic idea: the difference between luxuries and necessities. If, as many previous researchers had been doing, we merely ask, “What would you like in a mate?” we’ll get an answer analogous to what we’d get if we asked what you’d like in a car, a house, or a vacation. Whether you are a man or woman, you might say you’d very much like an all-expense-paid week on a secluded, private beach in Hawaii with a charming and sensitive traveling companion who looks like a movie star, followed by a drive home from the airport to your architect-designed home in your sporty new Mercedes. But of course, real people are not in a position to afford everything, so most of us need to settle.

  Li wanted to know what would happen if he had men and women work within a more limited (and realistic) budget when it came to mating. He asked men and women to design their ideal mate from a menu that included several desirable characteristics, such as physical attractiveness, social status and resources, warmth and kindness, creativity, and so on. To distinguish those characteristics that were necessities as opposed to luxuries, people were given a budget of “mate dollars” to spend on designing their ideal mate. If they spent more on one feature, they would have less left to spend on other features.

  When people had a high mate budget, men and women wanted similar things in a mate: both sexes wanted everything—the equivalent of a kind and affectionate movie star with a PhD, a villa in southern France, and a great sense of humor. But when faced with a more realistic, lower budget, men and women started spending very differently, prioritizing their necessities in distinct ways. Men placed first priority on physical attractiveness, with kindness second and status and resources way down in the list. Women, on the other hand, placed first priority on a man’s status and resources, followed by his kindness, with physical attractiveness way down in the list.

  This sex difference is, once again, not something peculiar to North America. Like American women, Japanese, Zambian, and Serbian women rate good financial prospects in a mate as more important than do men in those countries. Women everywhere place a great deal of emphasis on a mate’s status, ambition, and resources, regardless of his physical attractiveness. Men, by contrast, tend to prefer the good-looking woman regardless of her social class.

  WHY DO WOMEN SOMETIMES PAY FOR MEN?

  Given that women are the evolutionarily more valuable sex, it makes sense that most of the world’s societies impose a bride price, with men paying good money for a young and fertile wife. But then why do several societies have the custom of dowry—a payment made by the bride’s family at the time of a wedding? Why would women ever have to pay for men?

  An important clue comes from asking which societies have bride price and which have dowry. The more common practice of bride price is found in the majority of traditional societies, which tend to be poor. Dowry only arose more recently with the emergence of large nation-states, such as in China, India, and parts of Europe. In these societies, citizens for the first time in history were able to accumulate substantial wealth, and families were able to pass their accumulated wealth, and thereby their status, on to their children. The increased wealth created a new opportunistic niche for dowry.

  But the relatively modern custom of dowry is not the mirror image of bride price. Whereas bride price entails a man paying for sexual access to a fertile woman, dowry does not entail a woman paying for se
xual access to a fertile man. As we saw in the college campus study, a woman can have that for free. Instead, dowry involves a woman’s family making an investment to ensure that the daughter ends up with a husband who is well positioned to make investments in their grandchildren.

  In “Sociology of Bride Price and Dowry,” Shalini Randeria and Leela Visaria explain that “dowry is property given to the bride by her kin, to take with her to her husband’s family.” Dowries are essentially resource supplements that a bride receives from her kin to start a new family with her husband, who is required to bring his own resources as well. As Randeria and Visaria explain, dowry is “property which belongs to the woman, and which may be controlled jointly by her husband, who does not have the right to dispose of it.” If the couple were to divorce, for example, the dowry would revert to the woman.

  In a society where some families have much more status and wealth than others, a woman’s family can make an investment in a daughter’s future family by paying a dowry that will allow her to secure a husband from one of those wealthy, high-status families. But rather than payment for access to a fertile man, a dowry reflects a woman’s family investing in an alliance that promises to provide resources for her and her offspring.

  HIS AND HERS MATING SUBSELVES

  The recurring argument in this book is that our choices are guided by seven subselves, which take turns steering decision making. Most of the subselves work similarly in men and women, because both sexes needed to solve similar ancestral challenges. When it comes to avoiding disease, for example, men and women need to do similar things to ward off pathogens. But when it comes to mating, men and women face a slightly different set of challenges.

  The mating game involves solving two very different evolutionary challenges: acquiring mates and retaining them. As a consequence, we have different subselves assigned to each task. And not only do these subselves influence decisions that go far beyond sex and mating, but they also come in a his and hers version.

  SWINGING SINGLES: THE MATE-ACQUISITION GAME

  Back during our discussion of home economics, we observed that people use different rules to negotiate in different types of relationships. The decision about who pays for dinner, for example, is different when we’re dining out with our family or with our coworkers. When you’re trying to woo a new lover, the rules change once again. Both the man and the woman are trying to show off their positive attributes. Both sexes, for example, become more generous tippers when their mate-acquisition subself has been primed. But while both sexes put on displays of blatant generosity, men and women are actually advertising different things.

  Sex differences in the mate-acquisition game stem from the biological principle of minimum parental investment discussed earlier. Singles ads written by a man are more likely to advertise his own status or wealth (“company president,” “own home near beach,” “make six figures,” “enjoy skiing and yachting”), showing off the human equivalent of a peacock’s feathers. Women’s ads are instead likely to specify that their future partner must meet some minimum level of status or wealth (“college education a must,” “must make six figures”). And on the receiving end, men are more likely to respond to ads written by women in the years of peak fertility (perhaps accompanied by an attractive photo), whereas women are more likely to respond to ads that advertise men’s income and educational levels.

  Long before there were personal ads, of course, men and women did their best to advertise to the opposite sex. Throughout history and across human cultures, young men in their teens and twenties have taken great risks to acquire wealth and status—and to show it off. One consequence of all this showing off is that men are much more likely to die in accidents or conflicts with other men, especially during their teens and twenties, when the competition for mates is fiercest. In Spain, for example, men aged twenty-four to thirty-five are, compared to women of the same age, fully five times more likely to die in accidents and homicides rather than from natural disease processes. In areas where there is especially high income disparity (where the local poor are especially poorer than the local ricos), it’s even worse—with those desperate young men being six times more likely to die in accidents or violent altercations. And it isn’t just a Spanish machismo thing; the exact same pattern is seen in data from eighty-two countries around the globe. Young men everywhere are literally killing themselves for attention and status.

  In dozens of our own studies, we have activated men’s mate-acquisition subself by having them look at photos of attractive women or imagining going on a date or watching a romantic movie. We repeatedly find that a lustful state of mind leads men to start showing off and competing in various ways: becoming more reckless, adventurous, creative, aggressive, heroic, independent, and inclined to spend money on flashy products. In effect, men motivated to attract a mate turn into peacocks and scream to the world, “Look at me! I stand out from the crowd!”

  ALL THE SINGLE LADIES

  Women too want to stand out. But instead of showing off their wealth and bravado like men, women advertise something different. When a woman’s mate-acquisition subself is running the show, she becomes more agreeable, cooperative, and helpful. Ladies in a romantic frame of mind are more supportive and likelier to go along with the group; they’re also eager to assist other people in need. But this veneer of benevolence doesn’t mean that mating-minded women are less competitive. Rather, the competition involves being the nicest, the most supportive, and the most helpful.

  Recall that both men and women become more generous tippers when their mate-acquisition subself is in charge. Why? For a man, tipping is a way to advertise his wealth. Leaving large bills on a table or making a generous charitable donation shows that a man can afford to give money away. We know that giving money to charity for romance-minded men is about the money because when men are given the opportunity to be helpful in a way that doesn’t involve money or heroism, having romance on the mind no longer leads them to be more helpful. Activating the mate-acquisition subself did not lead men to want to go out and pick up trash in the park or do volunteer work. Men seem to ask: What’s the point in helping if there is no opportunity to flaunt money or machismo?

  For a woman, on the other hand, generous tipping is one way to advertise her caring nature. Leaving a large tip or making a donation can be a way for a woman to demonstrate that she cares about the well-being of others. As long as someone is around to see the act, a mate-attraction motive leads women to become more helpful, regardless of whether it involves money. Mating-minded women are more eager to volunteer to serve soup at a homeless shelter, dedicate their time to teach underprivileged kids to read, or spend the weekends nursing sick people back to health at the hospital. Whereas men want to draw attention to the size of their charitable spending, women want to draw attention to the charitable nature of the spending.

  Women seek to stand out in another way that gets to the heart of men’s and women’s biological difference in reproduction. Unlike men, women’s mate-acquisition subself does not lead them to throw caution to the wind and take brazen risks. But there is one telling exception. Women take more risks if doing so enhances their appearance. Women primed with a mate-attraction motive are more willing to take diet pills, for example, even when they know that the pills can cause heart problems later in life. And they are more willing to tan their bodies to enhance their appearance, even when they are aware that doing so can cause skin cancer.

  Women go to great lengths to be the fairest in the land and to advertise their beauty. They spend a great deal of time, energy, and money choosing clothes, accessories, and shades of makeup that enhance their attractiveness. Yearly spending on women’s fashion apparel in the United States alone is well over $100 billion—more than twice the amount the entire US national government spends on education!

  Americans also spend $11 billion per year on medical interventions to improve their looks, and 92 percent of the customers are women. Many women regularly risk in
fection, disability, and death to have their bodies surgically cut into, invasively rejiggered, and stitched together—all in the hope of enhancing signs of apparent fertility. The most popular cosmetic surgical procedure is breast augmentation, but the options on the menu include everything from facelifts to tummy tucks to the Brazilian butt lift, in which a woman’s own fat is transferred to enhance the shape and size of her buttocks. And if surgery sounds too invasive, consider the most popular nonsurgical procedure—a Botox injection, which involves pumping a paralyzing toxin into the facial muscles to reduce wrinkling around the eyes and mouth. Besides all that, women spend additional billions on books, magazines, and fitness classes designed to help them reduce the age-related accumulation of midsection fat and tone their leg muscles to look more like college students.

  Social psychologist Sarah Hill has found that women regard money spent on beauty as a necessity rather than a luxury. Hill and her colleagues examined what happens to women’s spending on beauty products in economic downturns. Normally during economic recessions, consumer spending decreases, especially on nonessential luxuries. But spending on necessities can actually increase in times of recession. For example, someone who normally eats cheap Top Ramen noodles once a week and homemade gourmet pasta on the other nights might need to start eating Top Ramen daily in a recession, increasing his or her proportionate spending on such inexpensive foods to ensure at least a bare minimum of calories.

  When Hill and her colleagues examined women’s spending in economic recessions, they found that while economic downturns lead women to spend less on most products, they spend more money on products that enhance appearance. For instance, sales figures from one of the world’s biggest cosmetics companies, L’Oreal, showed that during 2008, a year when the rest of the economy was suffering record declines in sales, L’Oreal experienced sales growth of 5.3 percent. Why the seemingly irrational splurging on cosmetics during economic recessions? Because when times are tough, it becomes even more important to attract one of those desirable guys with a good job. Just as economic inequality magnifies men’s competitiveness, economic hard times also magnify women’s investments in their appearance.