The Mating Mind: How Sexual Choice Shaped the Evolution of Human Nature (50 page)

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Authors: Geoffrey Miller

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BOOK: The Mating Mind: How Sexual Choice Shaped the Evolution of Human Nature
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Gentlemen and feminists understand the difference between contractual prostitution and male courtship gifts. When a man buys a woman dinner, she is emphatically not obliged to have sex with him. He would be a sexist cad for suggesting that she was. He cannot take her to a small claims court if she says, "Thank you for a lovely meal, but I do not believe we are suited to one another." Of course, an amorous male may be frustrated and resentful if his courtship fails, but that is not to say that the female has cheated him according to the terms of some implicit contract. It means that she has rejected him. It is her power of sexual choice that determines whether the relationship will escalate to intercourse, not his imposition of a gift. (However, in some cultures, if a couple continues to date and a woman accepts an escalating series of gifts over a long time period, this may create an implicit sexual contract.),

What's more, most males could not possibly afford to buy a woman's reproductive potential if courtship were a simple economic exchange. What would be an appropriate market price for a nine-month pregnancy, the pain of childbirth, the exhaustion of breast-feeding, and twenty years of maternal care? At least half a million dollars at a basic salary of $25,000, one would think. How much do men spend on courtship in the first few months? Perhaps a tenth of 1 percent of the proper market price. Their generosity might continue after a baby arrives, but it might not. One could do the same sort of analysis for hunter-

gatherers, in terms of the calorie cost of pregnancy and maternal care versus the calorie value of the meat that males offer. Are women just undervaluing themselves by a factor of a thousand? It seems unlikely that evolution could have produced such low female self-esteem, if the reciprocity theory is correct. Mutant women who demanded more should have replaced those who demanded so little, since their offspring would materially benefit.

Finally, male generosity during courtship is relatively inefficient as a way of transferring resources to females. It is like charity: we don't seem to care about the efficiency, only the cost of donation and the good intention. Efficient benefit-transfer is extremely unromantic. If human courtship evolved under the reciprocity model, it would be very, very simple. Today, women would auction their reproductive potential on the Internet, accepting wire transfers of bank funds from all male suitors, awarding their favors to the highest donor, and keeping all the money. Women would have emotions well adapted to falling in love with the most generous bidder—even though there were no interbank electronic transfers during the Pleistocene. The fact that we find this scenario so unappealing is psychological evidence against the reciprocity model.

Romantic gifts are those that are most useless to the women and most expensive to the man. Flowers that fade, candles that burn, overpriced dinners, and walks on exotic beaches are the stuff of modern romance. They do not increase a woman's survival prospects as much as they reduce a man's bank account. One might say that these things bring pleasure, but, as we have seen, pleasure is what evolution must explain. How could evolution possibly have favored humans who fall in love with individuals who provide them with useless luxuries that bring no survival benefit? The fact that a diamond engagement ring happens to be made out of durable matter does not make it a biologically relevant material benefit to a woman. If she wanted the diamond as a purely material benefit, she should not mind if her suitor bought it on sale from a mail-order catalog. But in reality, she wants him to pay the full retail price at Tiffany's,

because that is more "romantic," which is to say, costly. Moral philosophers might not consider male courtship generosity very "moral" behavior. But to a woman receiving a romantic gift, it is a capital virtue.

Sexual Selection for Sympathy

Empathy is the mental capacity to understand the suffering of others, while sympathy is the emotional capacity to care about that suffering. Much of human courtship consists of sympathy displays. We show kindness to children; we listen to sexual prospects enumerating their past sufferings. The development of emotional intimacy could be viewed as the mutual display of capacities for extremely high levels of sympathy.

When we favor kindness in courtship, we are favoring a real personality trait that has been measured and dissected by psychologists. In the leading "5-factor" model of personality, one of the factors is "agreeableness." People who score high on this trait are compassionate, loving, sincere, trustworthy, and altruistic. Empirical research shows that these personality features really do cluster together, and are fairly independent of other personality traits like conscientiousness, extroversion, and intelligence. When people are asked to rate personality features as positive or negative, the agreeableness feature always tops the charts. The worst-rated adjectives describe the opposite of agreeableness: dishonest, cruel, mean, phony. Also, agreeableness appears to be moderately heritable, so agreeable parents tend to produce agreeable children.

By looking for sympathy during courtship, people may also be trying to avoid psychopaths. True psychopathy ("antisocial personality disorder") is very rare, occurring in less than 1 percent of the population, but psychopaths account for a very high proportion of murders, rapes, assaults, and other serious crimes. Psychopathy is basically the absence of sympathy. There are fewer female psychopaths, perhaps because female psychopaths would not have shown sufficient sympathy to their babies in past generations. But an absence of parental sympathy

did not consign male psychopaths to reproductive oblivion. On the contrary, male psychopaths tend to seduce women, get them pregnant, and abandon them. Women prefer to avoid this, so psychopaths know they must feign agreeableness during courtship. Very few psychopaths flaunt their lack of sympathy like Hannibal Lecter, because very few of them are glamorous, urbane geniuses. Mostly, they are just ordinary creeps who beat their girlfriends, stab guys in bars for no reason, get caught, and then apply for parole four times as often as non-psychopaths because they don't think they've done anything wrong.

If sexual preferences evolved to avoid anything, they should have evolved to avoid psychopaths. During human evolution there may have been a three-way arms race: females developed better tests for male sympathy, male psychopaths developed better ways to fake sympathy, and male non-psychopaths developed sympathy-displays that were harder and harder to fake. Just as fitness indicators evolved to advertise freedom from harmful mutations, perhaps sympathy indicators evolved to advertise freedom from psychopathy.

The psychologist Hans Eysenck argued that, apart from true psychopathy, there is a much more common personality trait of psychoticism in which people are aggressive, cold, egocentric, impersonal, antisocial, unempathetic, and tough-minded. Like psychopathy itself, these features are not generally favored in sexual relationships, though they may bring advantages in dominance contests. In our current context, the interesting thing about psychoticism is that the innate depravity view of human morality mistook one extreme of this personality dimension for the whole of human nature. People with extreme psychoticism are perfectly capable of nepotism and strategic reciprocity when it suits them—they just lack the sympathy and agreeableness that average people have. If one equates evolutionary egoism with psychological egoism, it looks as if all humans should be psychopaths. That prediction is wrong, because there is a hidden sexual-selective advantage to sympathy.

Our sexually selected instincts for displaying sympathy tend to

affect our belief systems, not just our charity and courtship behavior. When individuals espouse ideological positions, we typically interpret their beliefs as signs of good or bad moral character. Individuals feel social pressure to adopt the beliefs that are conventionally accepted as indicating a "good heart," even when those beliefs are not rational. We may even find ourselves saying, "His ideas may be right, but his heart is clearly not in the right place." Political correctness is one outcome of such attributions. For example, if a scientist says, "I have evidence that human intelligence is genetically heritable," that is usually misinterpreted as proclaiming, "I am a disagreeable psychopath unworthy of love." The arbiters of ideological correctness can create the impression that belief A must indicate personality trait X. If X is considered sexually and socially repulsive, then belief A becomes taboo. In this way our sexually selected instincts for moralistic self-advertisement become subverted into ideological dogmas. I think that human rationality consists largely of separating intellectual argument from personality attributions about moral character. Our difficulty in making this separation suggests that political, religious, and pseudo-scientific ideologies have been part of moralistic self-display for a very long time.

Sexual Fidelity and Romantic Love

Sleep around with too many people, and your lover will probably leave you. Sexual choice is not just the power to initiate relationships, but the power to end them. Our capacity for sexual fidelity, imperfect though it may be, is a result of our ancestors favoring the faithful by breaking up with the unfaithful. As David Buss has emphasized, humans have evolved specialized emotions for detecting and punishing infidelity in sexual relationships, distinct from our instincts for detecting cheats in reciprocity relationships.

Evolutionary psychology has rightly stressed how pervasive human sexual infidelity is when compared with the cultural ideal of monogamous commitment. The greater tendency of males to philander is certainly consistent with the predictions of sexual

selection theory. However, I also find it astonishing how faithful most humans are when compared with other mammals. Some male birds are relatively faithful, but most male primates never turn down an opportunity to copulate with a willing female. Other female primates show no sense of sexual commitment to a particular male. If a better male comes along and a female is not too afraid of a jealous beating (as can often happen to female chimpanzees), she may switch partners. Humans are different. We value sexual fidelity in others, and have the capacity to inhibit our own courtship and copulation behavior, even in the face of awesome temptation.
Fidelity could be viewed as an example of reciprocity, insofar as cheating by one individual tends to provoke punishment by the other. However, the punishment is usually implemented by sexual choice. The "punisher" ends the relationship, denies further sexual access, or chooses to have sex with someone else. It may not matter whether we view this as sexual choice in the service of reciprocity, or reciprocity in the service of sexual choice. In either case, sexual preferences favor the virtue.
Sexual selection produced a sort of two-stage defense against sexual infidelity: romantic love, and then companionate sexual commitment. Romantic love powerfully focuses all courtship effort on a single individual to the exclusion of others. For at least a few weeks or months, it inhibits infidelity. Needless to say, romantic love is sexually attractive. It may not increase the appeal of an otherwise unattractive individual enough to provoke mating, but, all else being equal, it is clearly valued in mate choice. Love evolved through sexual selection, not least because it signaled fidelity.
However, passionate sexual love, "being in love," rarely lasts more than a couple of years. That is not nearly long enough to keep a couple together to raise a toddler, which they may have a shared interest in doing. Much more important over the long term is the feeling of friendly, mutually respectful sexual commitment. This does not work by shutting off all sexual attraction to others, but by managing that attraction through flirtation and

sexual fantasy. The human capacity for flirtation (sexually inhibited pseudo-courtship) is one of the modern world's most underrated virtues, the principal spice of adult social life throughout history Equally important is sexual fantasy the spice of adult mental life. It permits sexual infidelity in the virtual reality of the imagination, without offending one's real sexual partner as much as a real affair would.

Our sexual fidelity evolved as a compromise between two selection pressures. On the one hand there was sexual selection favoring high fidelity through romantic love and sexual commitment. On the other hand there were the potential reproductive benefits of philandering. Especially for males, those potential benefits made it maladaptive to completely turn off their sexual attraction to everyone other than their partners. Flirtation and fantasy sometimes escalated into real affairs, and those affairs sometimes gave our ancestors net reproductive benefits. Sexual choice could not reach into our minds and totally eliminate polygamous desires. It could only punish observable infidelity and blatantly wandering eyes. We are not always sexually faithful, but that does not mean that our capacity for fidelity is a flawed adaptation. It may be perfectly adapted to a Pleistocene world in which the highest reproductive success went to those who were almost always faithful, except when a significantly more attractive option arose.

Virtues of Good Fathers

Male courtship generosity does not usually end after the first copulation, or even after the first baby arrives. As we saw in Chapter 7, many men are fairly good and generous fathers, even to their step-children. They do nowhere near as much hands-on child care as mothers, of course, but do vastly more than most male primates. We saw how fatherly solicitude could be interpreted as courtship effort rather than parental effort. Women may break up with bad fathers and continue to sleep with good fathers, and that would have been sufficient sexual selection to favor good fathers. There is not much more to say about that here,

other than to put the virtues of fatherhood in this chapter's moral context.
The generosity of step-fathers in particular cannot be explained by nepotism or reciprocity. The step-children will probably never reciprocate, and to say that their mother "reciprocates" with sex just trivializes her mate choice. Of course, good mothering is a virtue as well, but natural selection has already been favoring it for 200 million years of mammalian evolution. Indeed, the maternal virtues of female mammals, including their capacity for milk production, were a major factor in the success of mammals. Beyond that mammalian legacy, male mate choice may have favored some indicators of mothering ability in women, such as a conspicuous interest in unrelated babies and children, and a verbose pride in the achievements of one's own children. Sarah Blaffer Hrdy has recently analyzed these human maternal virtues in her book
Mother Nature.

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