The females of our closest primate relatives, the chimpanzees, are not exactly paragons of sexual probity. A recent DNA study of behavior. in the forest of Africa’s Ivory Coast showed that despite the hurrying of local males, the wily females were stealing off so often that half their offspring turn out to be fathered by outsiders. Of bonobos, perhaps the less said the better, at least in a family magazine. These 'pygmy chimps', as they are also known, share 98% of our genes and a tendency to what Freud termed 'polymorphous perversity'. They will have sex with anyone, male of female as readily as we humans shake hands and apparently for the same purpose. The interesting thing is that female promiscuity seems to be a reproductively advantageous trait, which may explain why it prevails in the animal world. The more males a female prairie dog mates with, for example, the more likely she is to conceive and the larger her litters. Angier reports on data, still disputed, that suggest human females are more likely to get pregnant for sex with an adulterous lover than from sex with their spouse. So, to the extent that females relied on male help in raising a family, the smartest female reproductive strategy may have involved no less treachery than the male one: behave promiscuously, so you' 11 be sure to get pregnant, but pretend to be monogamous professing undying love -- so that at least one of the fellows will think the kids are his and possibly take an interest in them. Hey, it fooled the evolutionary psychologists! Men fall for pretty faces, women fall for healthy portfolios? Here’s another object lesson sometimes drawn from the evolutionary allegory of Monica and Bill: men go for beautiful women, while women are attracted to power and money, even when it comes in a fat, gray-haired middle-bound millionaire husband, there are more cases like ex-playmate Anna Nicole Smith and her late, wheelchair-bound millionaire husband, there are like elementary school teacher Mary Letourneau and her 13-year-old boyfriend. But since men tend to accrue wealth and power as they age, it’s a bit odd, as zoologist Desmond Moils once noted, that baleness doesn't necessarily activate the feminine positive response. It may be smart for women to go for the billionaires and tribal big shots, but in practice their choices are often politically and economically irrational, if not self-destructive. For example, Juliet fell for a scion of the enemy clan. In rock-and-roll tradition and movies from The Wild One to Shakespeare in Love. It’s the penniless who makes the girls scream -- and did anyone see Titanic? There is in fact a respectable evolutionary rationale for such 'irrational' female choices. Women may want loyal, provider-type mates to help them raise their children. But if their sons are not attractive to other women -- and hence keep the lineage thriving -- it might help if dad is a heartbreaker himself. Unfortunately, though, physical attractiveness is net a re- liable guide to reproductive 'fitness', as in health and wealth. Consider the peacock, its gorgeous tall renders it fairly vulnerable to predators, so any peahen with a concern for her sons' longevity should opt for a more modestly cute one. According to the information given in the first paragraph, we can infer that ______.