What Do Women Want

narcissism, Sarah Blaffer Hrdy, a primatologist and anthropology professor at the University of California at Davis, raised evolutionary reasons. Her ideas challenged evolutionary psychologists who insisted that women are the less libidinous sex, the sex more suited to be monogamous. Hrdy had begun her career studying langurs in India. Within these monkeys, their jet-black faces surrounded by cloud-colored fur, the males commit rampant infanticide. They swoop in to kill newborns not their own. The same goes for the males in a number of other primate species. And female promiscuity among these types of monkeys and baboons evolved, Hrdy believed, partially as a shield: it masked paternity. If a male couldn’t be sure which babies were his, he would be less prone to murder them. This insight didn’t apply to all of our close animal ancestors; among the rhesus, the males tend toward caution and infanticide is seldom seen. Piecing together evolution’s logic was an incremental process, full of incomplete patterns, causes that weren’t universal. But Hrdy, with her theory of promiscuity as protective, added a compelling element within our ancestry.
    And alongside this theory, she put forward an idea that might be relevant to countless species. It revolved around orgasm. Female climax—in humans and, if it exists, in animals—has been viewed by many evolutionary psychologists as a biologically meaningless by-product, a hapless cousin to male orgasm, with no effect on reproduction. Male nipples fall into this category; men don’t give milk and don’t need to for the sake of perpetuating humankind. The miniature look of the clitoris, compared to the penis, has helped to make the argument that female climax has no Darwinian importance, because the clitoris can have the appearance of a puny afterthought.
    Somehow, this perspective has survived the recent mapping of the organ’s underlying bulbs and wings. And the length of stimulation some women need to reach orgasm has reinforced the by-product argument; if the event had evolutionary significance, it wouldn’t be elusive, unguaranteed. Especially during intercourse, it would happen more readily.
    But the clitoral expanse—touched through the vagina—rivals the penis in total nerve-suffused territory. And as for the slowness of ecstasy, Hrdy flipped predominant thinking upside down. Her vision was a vivid example of substituting a female lens for a male one. Female orgasm could well be thoroughly relevant among our ancestors. Its delay, its need of protracted sensation, wasn’t a contradiction but a confirmation of this; it was evolution’s method of making sure that females are libertines, that they move efficiently from one round of sex to the next and frequently from one partner to the next, that they transfer the turn-on of one encounter to the stimulation of the next, building toward climax.
    And the possibility of multiple orgasms compounded libertine motives. Another opioid rush—or a series of opioid infusions—might be in store with the next mounting. The advantages female animals get from their pleasure-driven behavior, Hrdy asserted, range from the safeguarding against infanticide in some primate species to, in all, gathering more varied sperm and so gaining better odds of genetic compatibility, of becoming pregnant, of bearing and raising healthy offspring.
    Hrdy’s stance on female orgasm as something probably much more than an evolutionary footnote was supported in another way. The data Pfaus had spoken about, of orgasm-like contractions in rats leading to greater chances of conception, matched fledgling, controversial evidence in women of climactic spasms guiding sperm up into the uterus. But even if female animals weren’t actually having orgasms, weren’t having the all-consuming subjective experience that we do, Hrdy’s basic position about female pleasure held. Abundant stimulation was its own reward, reproductive benefit was its ultimate payoff, and in our near ancestors, this augered against monogamy.
    Hrdy noted, too, proclivities in species more distant, polyandry from prairie dogs to sparrows. Or take the female of an arachnid called the book scorpion. Let her have sex with one male and, afterward, offer her that same partner. Forty-eight hours will have to go by before she’s interested in mating again, though he is full of sperm and fully motivated. She seems wired to accrue an assortment of lovers and an array of sperm. Present