The Queen - Matt Ridley

Nonetheless, attempts have been made. The 570 or so Ache people of Paraguay were hunter-gatherers until 1971, living in twelve bands. They then gradually came into contact with the outside world and were lured onto government reservations run by missionaries: Today, they no longer depend on hunted meat and gathered fruit but grow most of their own food in gardens. But when they still depended on men's hunting skills for much of their food, Kim Hill of the University of New Mexico found an intriguing pattern: Ache men would donate any spare meat they had caught to women with whom they wanted to have sex. They were not doing so to feed children they might have fathered but as direct payment for an affair: It was not easy to discover. Hill found that he was gradually forced to drop questions about adultery from his studies because the Ache, under missionary influence, became increasingly squeamish about discussing the subject. The chiefs and the head men were especially reluctant to talk about it, which is hardly surprising in view of the fact that they were the ones having the most affairs. Nonetheless, by relying on gossip Hill was able to piece together the pattern of adultery in the Ache: As expected, he found that high-ranking men were involved most, which is consistent with the idea of having your paternal-genetic cake and eating it: However, unlike in birds, it was not just the wives of low-ranking men who indulged. It is true that Ache adulterers frequently ply their mistresses with gifts of meat, but Hill thinks the most important motive is that Ache women are constantly preparing for the possibility that they will be deserted by their husbands. They are building up alternative relationships and are more likely to be unfaithful if the marriage is going badly. That is, of course, a double-edged sword: The marriage could break up because the affair is discovered:''

Whatever the motive for women, Hill and others believe that adultery has been much underemphasized as an influence in the evolution of the human mating system. In hunter-gatherer societies the male opportunist streak would have been far more easily satisfied by adultery than by polygamy. In only two known hunter-gatherer societies is polygamy either common or extreme. In the rest it is rare to find a man with more than one wife and very rare MONOGAMY AND THE NATURE OF WOMEN

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to find a man with more than two. The two exceptions prove the rule. One is among the Indians of the Pacific Northwest of America, who depended on abundant and reliable supplies of salmon and were more like farmers than hunter-gatherers in their ability to stockpile surpluses: The other is certain tribes of Australian aborigines, which practice gerontocratic polygamy: Men do not marry until they are forty, and by the age of sixty-five they have usually accumulated up to thirty wives: But this peculiar system is far from what it seems. Each old man has younger assistant men whose help, protection, and economic support he purchases by, among other things, turning a blind eye to their affairs with his wives. The old man looks the other way when the helpful nephew carries on with one of his junior wives.28

Polygamy is rare in hunter-gatherer societies, but adultery is common wherever it has been looked for. By analogy with monogamous colonial birds, therefore, one would expect to find human beings practicing either mate guarding or frequent copulation: Richard Wrangham has speculated that human beings practice mate guarding in absentia: Men keep an eye on their wives by proxy.

If the husband is away hunting all day in the forest, he can ask his mother or his neighbor whether his wife was up to anything during the day. In the African pygmies Wrangham studied, gossip was rife and a husband 's best chance of deterring his wife 's affairs was to let her know that he kept abreast of the gossip. Wrangham went on to observe that this was impossible without language, so he speculated that the sexual division of labor, the institution of child-rearing marriages, and the invention of language—three of the most fundamental human characteristics shared with no other ape—all depend on another. 29

WHY THE RHYTHM METHOD DOES NOT WORK

What happened before language allowed proxy mate guarding?

Here, anatomy provides an intriguing clue: Perhaps the most startling difference between the physiology of a woman and that of a

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The Red Queen

female chimpanzee is that it is impossible for anybody, including the woman herself, to determine precisely when in the menstrual cycle she is fertile. Whatever doctors, old wives ' tales, and the Roman Catholic Church may say, human ovulation is invisible and unpredictable. Chimpanzees become pink; cows smell irresistible to bulls; tigresses seek out tigers; female mice solicit male mice—

throughout the mammal order, the day of ovulation is announced with fanfare. But not in man. A tiny change in the woman 's temperature, undetectable before thermometers, and that is all. Women 's genes seem to have gone to inordinate lengths to conceal the moment of ovulation:

With concealed ovulation came continual sexual interest.

Although women are more likely to initiate sex, masturbate, have an affair with a lover, or be accompanied by their husband on the day of ovulation than on other days,'° it is nonetheless true that human beings of both sexes are interested in sex at all times of the menstrual cycle; both men and women have intercourse whenever they feel like it, without reference to hormonal events. Compared with many animals, we are astonishingly hooked on copulation.

Desmond Morris called mankind " the sexiest primate alive " " (but that was before anybody studied bonobos): Other animals that copulate frequently—lions, bonobos, acorn woodpeckers, goshawks, white ibises—do so for reasons of sperm competition.

Males of the first three species live in groups that share access to females, so every male must copulate as frequently as he can or risk another male 's sperm reaching the egg first. Goshawks and white ibises do so to swamp any sperm that might have been received by the female while the male was away at work. Since it is clear that humanity is not a promiscuous species—even the most carefully organized free-love commune soon falls apart under the pressure of jealousy and possessiveness—the case of the ibis is the most perti-nent for man: a monogamous colonial animal driven by the threat of adultery into the habit of frequent copulation. At least the male ibis need only keep his sex-six-times-a-day routine up for a few days each season before egg laying. Men must keep up sex twice a week for years."

MONOGAMY AND THE NATURE OF WOMEN

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But concealed ovulation in women cannot have evolved for the convenience of the man. In the late 1970s there was a flurry of speculative theorizing about the evolutionary cause of concealed ovulation. Many of the ideas apply only to human beings. An example is Nancy Burley 's suggestion that ancestral women with unconcealed ovulation learned to be celibate when fertile because of the uniquely painful and dangerous business of human childbirth; but such women left behind no descendants, so the rare exceptions who could not detect their own ovulation mothered the human race. Yet concealed ovulation is a habit we share with some monkeys and at least one ape (the orangutan). It is also a habit we share with nearly all birds. Only our absurdly parochial anthropocentrism has allowed us to think that silent ovulation is special.

Nonetheless, it is worth going through the attempted explanations of what Robert Smith once called human "reproductive inscrutability " because they shed an interesting light on the theory of sperm competition. They come in two kinds: those suggesting concealed ovulation as a way of ensuring that fathers did not desert their young, and those suggesting the exact opposite: The first kind of argument went as follows: Because he does not know when his wife is fertile, a husband must stay around and have sex with her often to be sure of fathering her children. This keeps him from mischief and ensures he is still around to help rear the babies."