The Moral Animal: Why We Are, the Way We Are: The New Science of Evolutionary Psychology (16 page)

This Darwinian analysis of marriage complicates the choice between monogamy and polygyny. For it shows that the choice isn't between equality and inequality. The choice is between equality among men and equality among women. A tough call.

There are several conceivable reasons to vote for equality among
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men (that is, monogamy). One is to dodge the wrath of the various feminists who will not be convinced that polygyny liberates downtrodden women. Another is that monogamy is the only system that, theoretically at least, can provide a mate for just about everyone. But the most powerful reason is that leaving lots of men without wives and children is not just inegalitarian; it's dangerous.

The ultimate source of the danger is sexual selection among males. Men have long competed for access to the scarcer sexual resource, women. And the costs of losing the contest are so high (genetic oblivion) that natural selection has inclined them to compete with special ferocity. In all cultures, men wreak more violence, including murder, than women. (Indeed, across the animal kingdom, males are the more belligerent sex, except in those species, such as phalaropes, where male parental investment is so high females can reproduce more often than males.) Even when the violence isn't against a sexual rival, it often boils down to sexual competition. A trivial dustup may escalate until one man kills another to "save face" — to earn the sort of raw respect that, in the ancestral environment, could have raised status and brought sexual rewards.
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Fortunately, male violence can be dampened by circumstance. And one circumstance is a mate. We would expect womanless men to compete with special ferocity, and they do. An unmarried man between twenty-four and thirty-five years of age is about three times as likely to murder another male as is a married man the same age. Some of this difference no doubt reflects the kinds of men that do and don't get married to begin with, but Martin Daly and Margo Wilson have argued cogently that a good part of the difference may lie in "the pacifying effect of marriage."
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Murder isn't the only thing an "unpacified" man is more likely to do. He is also more likely to incur various risks — committing robbery, for example — to gain the resources that may attract women. He is more likely to rape. More diffusely, a high-risk, criminal life often entails the abuse of drugs and alcohol, which may then compound the problem by further diminishing his chances of ever earning enough money to attract women by legitimate means.
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This is perhaps the best argument for monogamous marriage, with its egalitarian effects on men: inequality among males is more
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socially destructive — in ways that harm women and men — than inequality among women. A polygynous nation, in which large numbers of low-income men remain mateless, is not the kind of country many of us would want to live in.

Unfortunately, this is the sort of country we already live in. The United States is no longer a nation of institutionalized monogamy. It is a nation of serial monogamy. And serial monogamy in some ways amounts to polygyny.
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Johnny Carson, like many wealthy, high-status males, spent his career monopolizing long stretches of the reproductive years of a series of young women. Somewhere out there is a man who wanted a family and a beautiful wife and, if it hadn't been for Johnny Carson, would have married one of these women. And if this man has managed to find another woman, she was similarly snatched from the jaws of some other man. And so on — a domino effect: a scarcity of fertile females trickles down the social scale.

As abstractly theoretical as this sounds, it really can't help but happen. There are only about twenty-five years of fertility per woman. When some men dominate more than twenty-five years' worth of fertility, some man, somewhere, must do with less. And when, on top of all the serial husbands, you add the young men who live with a woman for five years before deciding not to marry her, and then do it again (perhaps finally, at age thirty-five, marrying a twenty-eight-year-old), the net effect could be significant. Whereas in 1960 the fraction of the population age forty or older that had never married was about the same for men and women, by 1990 the fraction was markedly larger for men than for women.
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It is not crazy to think that there are homeless alcoholics and rapists who, had they come of age in a pre-1960s social climate, amid more equally distributed female resources, would have early on found a wife and adopted a lower-risk, less destructive lifestyle. Anyway, you don't have to buy this illustration to buy the point itself: if polygyny would indeed have pernicious effects on society's less fortunate men, and indirectly on the rest of us, then it isn't enough to just oppose legalized polygyny. (Legalized polygyny wasn't a looming political threat last time I checked, anyway.) We have to worry about the de facto polygyny that already exists. We have to ask not
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whether monogamy can be saved, but whether it can be restored. And we might be enthusiastically joined in this inquiry not only by discontented wifeless men, but by a large number of discontented former wives — especially the ones who had the bad fortune to marry someone less wealthy than Johnny Carson.

This view of marriage is a textbook example of how Darwinism can and can't legitimately enter moral discourse. What it can't do is furnish us with basic moral values. Whether, for example, we want to live in an egalitarian society is a choice for us to make; natural selection's indifference to the suffering of the weak is not something we need emulate. Nor should we care whether murder, robbery, and rape are in some sense "natural." It is for us to decide how abhorrent we find such things and how hard we want to fight them.

But once we've made such choices, once we have moral ideals, Darwinism can help us figure out which social institutions best serve them. In this case, a Darwinian outlook shows the prevailing marital institution, serial monogamy, to be in many ways equivalent to polygyny. As such, this institution is seen to have inegalitarian effects on men, working against the disadvantaged. Darwinism also highlights the costs of this inequality — violence, theft, rape.

In this light, old moral debates assume a new cast. For example, the tendency of political conservatives to monopolize the argument for "family values" starts to look odd. Liberals, concerned about the destitute, and about the "root causes" of crime and poverty, might logically develop a certain fondness for "family values." For a drop in the divorce rate, by making more young women accessible to low-income men, might keep an appreciable number of men from falling into crime, drug addiction, and, sometimes, homelessness.
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Of course, given the material opportunities that polygyny (even de facto polygyny) may afford poor women, one can also imagine a liberal argument against monogamy. One can even imagine a liberal feminist argument against monogamy. And, in any event, one can see that a Darwinian feminism will be a more complicated feminism.

Viewed in Darwinian terms, "women" are not a naturally coherent interest group; there is no single sisterhood.
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There is one other kind of fallout from current marital norms that comes into focus through the new paradigm: the toll taken on children. Martin Daly and Margo Wilson have written, "Perhaps the most obvious prediction from a Darwinian view of parental motives is this: Substitute parents will generally tend to care less profoundly for children than natural parents." Thus, "children reared by people other than their natural parents will be more often exploited and otherwise at risk. Parental investment is a precious resource, and selection must favor those parental psyches that do not squander it on nonrelatives."
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To some Darwinians, this expectation might seem so strong as to render its verification a waste of time. But Daly and Wilson took the trouble. What they found surprised even them. In America in 1976, a child living with one or more substitute parents was about one hundred times more likely to be fatally abused than a child living with natural parents. In a Canadian city in the 1980s, a child two years of age or younger was seventy times more likely to be killed by a parent if living with a stepparent and natural parent than if living with two natural parents. Of course, murdered children are a tiny fraction of the children living with stepparents; the divorce and remarriage of a mother is hardly a child's death warrant. But consider the more common problem of nonfatal abuse. Children under ten were, depending on their age and the particular study in question, between three and forty times more likely to suffer parental abuse if living with a stepparent and a natural parent than if living with two natural parents.
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It is fair to infer that many less dramatic, undocumented forms of parental indifference follow this rough pattern. After all, the whole reason natural selection invented paternal love was to bestow benefits on offspring. Though biologists call these benefits "investment," that doesn't mean they're strictly material, wholly sustainable through monthly checks. Fathers give their children all kinds of tutelage and guidance (more, often, than either father or child realizes) and guard them against all kinds of threats. A mother alone simply can't pick up the slack. A stepfather almost surely won't pick up much, if any
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of it. In Darwinian terms, a young stepchild is an obstacle to fitness, a drain on resources.

There are ways to fool mother nature, to induce parents to love children that aren't theirs. (Hence cuckoldry.) After all, people can't telepathically sense that a child is carrying their genes. Instead, they rely on cues that, in the ancestral environment, would have signified as much. If a woman feeds and cuddles an infant day after day, she may grow to love the child, and so may a man who has been sleeping with her for years. This sort of bonding is what makes adopted children lovable and nannies loving. But both theory and casual observation suggest that, the older a child is when first seen by the substitute parent, the less likely deep attachment is. And a large majority of children who acquire stepfathers are past infancy.

One can imagine arguments among reasonable and humane people over whether a strongly monogamous society is better than a strongly polygynous one. But this much seems less controversial: whenever marital institutions — in either kind of society — are allowed to dissolve, so that divorce and unwed motherhood are rampant, and many children no longer live with both natural parents, there will ensue a massive waste of the most precious evolutionary resource: love. Whatever the relative merits of monogamy and polygyny, what we have now — serial monogamy, de facto polygyny — is, in an important sense, the worst of all worlds.

Obviously, Darwinism won't always simplify moral and political debate. In this case, by stressing the tension between equality among men and among women, it actually complicates the question of which marital institutions best serve our ideals. Still, the tension was always there; at least now it's in the open, and debate can proceed in stronger light. Further, once we have decided, with help from the new paradigm, which institutions best serve our moral ideals, Darwinism can make its second kind of contribution to moral discourse: it can help us figure out what sorts of forces — which moral norms, which social policies — help nourish those institutions.
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And here comes another irony in the "family values" debate: conservatives may be surprised to hear that one of the best ways to strengthen monogamous marriage is to more equally distribute income.
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Young single women will feel less inclined to tempt husband A away from wife A if bachelor B has just as much money. And husband A, if he's not drawing flirtatious looks from young women, may feel more content with wife A, and less inclined to notice her wrinkles. This dynamic presumably helps explain why monogamous marriage has often taken root in societies with little economic stratification.

One standard conservative argument against antipoverty policies is their cost: taxes burden the affluent and, by reducing their incentive to work, lower overall economic output. But if one goal of the policy is to bolster monogamy, then making the affluent less affluent is a welcome side effect. Monogamy is threatened not just by poverty in an absolute sense but also by the relative wealth of the wealthy. That reducing this wealth cuts overall economic output may, of course, still be regrettable; but once we add more stable marriages to the benefits of income redistribution, the regret should lose a bit of its sting.

One might imagine that this whole analysis is steadily losing its relevance. After all, as more women enter the workforce, they can better afford to premise their marital decisions on something other than the man's income. But remember: we're dealing with women's deep romantic attractions, not just their conscious calculation, and these feelings were forged in a different environment. To judge by hunter-gatherer societies, males during human evolution controlled most of the material resources. And even in the poorest of these societies, where disparities in male wealth are hard to detect, a father's social status often translates subtly into advantages for offspring, material and otherwise, in ways that a mother's social status doesn't.
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Though a modern woman can of course reflect on her wealth and her independently earned status, and try to gauge marital decisions accordingly, that doesn't mean she can easily override the deep aesthetic impulses that had such value in the ancestral environment. In fact, modern women manifestly do not override them. Evolutionary
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psychologists have shown that the tendency of women to place greater emphasis than men on a mate's financial prospects persists regardless of the income or expected income of the women in question.
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