What Do Women Want?: Adventures in the Science of Female Desire - Daniel Bergner (2013)

Chapter 4. Monkeys and Rats

Her unruly red-blond hair tufting atop her head, Deidrah sat beside Oppenheimer. She lipped his ear. She mouthed his chest. She kissed his belly over and over, lips lingering with each kiss. After a while, he pulled himself up and strolled away from her attentions, glancing back over his shoulder to see if she was following. She was.

Deidrah, who was probably the most reserved female monkey in the compound, started in again on his white-haired torso as they sat together on a concrete curb. The habitat, a one-hundred-and-twenty-foot square, was filled with ladders and ropes and assorted apparatus donated by a local fire department and by McDonald’s; an environment of trees and vines would have been too expensive to create and maintain. A trio of monkey children sprinted toward a tube, disappeared inside it, burst from the other end, and raced around for another run-through, berserk with joy.

From a platform on a steel tower, I watched with Kim Wallen, his beard silver, his eyes alight. A psychologist and neuroendocrinologist, he spent much of his time here at Yerkes, an Emory University research center outside Atlanta that was home to two thousand primates. We gazed down at the habitat’s seventy-five rhesus, a monkey species that had been sent into orbit in spaceships, in the fifties and sixties, as stand-ins for humans to see if we could survive trips to the moon. Wallen had lived on a farm as a child when his father, a psychologist, decided to try out a utopian dream of cooperative goat-rearing. Wallen’s observation of animal sexuality had begun then. He’d been watching monkeys now for decades.

“Females were passive. That was the theory in the middle seventies. That was the wisdom,” he remembered the start of his career. Deidrah’s face, always a bit redder than most, was luminous this morning, lit scarlet with lust as she lifted it from Oppenheimer’s chest. “The prevailing model was that female hormones affected female pheromones—affected the female’s smell, her attractivity to the male. The male initiated all sexual behavior.” What science had managed to miss in the monkeys—what it had effectively erased—was female desire.

And it had missed more than that. In this breed used as our astronaut doubles, females are the bullies and murderers, the generals in brutal warfare, the governors. This had been noted in journal articles back in the thirties and forties, but thereafter it had gone mainly unrecognized, the articles buried and the behavior oddly unperceived. “It so flew in the face of prevailing ideas about the dominant role of males,” Wallen said, “that it was just ignored.”

What mostly male scientists had expected and likely wanted to see appeared to have blinded them. Wallen’s career had been about pulling away the blinders. At the moment, below us, one female clawed fiercely at another, bit into a leg, whipped the weaker one back and forth like a weightless doll. Harrowing shrieks rose up. Four or five more monkeys joined in, attacking the one, who escaped somehow, sped away, was caught again. The shrieks grew more plaintive, more piercing, the attackers piling on, apparently for the kill, then desisting inexplicably. Assaults like this flared often; Wallen and his team usually couldn’t glean the reasons. Full battle—one female-led family’s attempt to overthrow another—was rare. That tended toward death: death from wounds and, some veterinarians thought, from sheer fright and shock. Occasionally the compound was littered with corpses.

When he thought about the way science had somehow kept itself oblivious to female monkey lust for so long, Wallen blamed not only preconceptions but the sex act itself. “When you look at the sexual interaction, it’s easy to see what the male is doing; he’s thrusting. It takes really focusing on the entire interaction to see all that the female is doing—and once you truly see it, you can never overlook it again.”

Deidrah fingered Oppenheimer’s belly, caressing, desperate to win his favors. He flopped down on his front, inert in a strip of sun. She kissed where she could get access, his ear again. The red of her face bordered on neon. She was near or in the midst of ovulation, her libidinous hormones high. When it comes to their cycles and sex, female monkeys are somewhere between lower mammals and humans; rhesus mating isn’t limited to the time of ovulation, but in most situations, that’s when it’s a lot more likely to occur.

What was happening between Deidrah’s ovaries and her brain as she stalked and stroked Oppenheimer is only partially understood, and the ways that biochemistry affects desire in women is even more complicated. Basically, though, sex hormones produced by the ovaries and adrenal glands—testosterone, estrogen—prime the primitive regions of the brain, territory lying not far from the brain stem and shared by species from Homo sapiens to lizards. This hormonal bathing then affects the intricate systems of neurotransmitters, like dopamine, that send signals within the brain, and this, in turn, alters perception and leads—in people and monkeys, in dogs and rats—to lust. The belief that animals, especially species less advanced than primates, don’t experience lust, that their mating is scripted to the point of making them sexual automatons, is wrong, as Jim Pfaus, a neuroscientist at Concordia University in Montreal, would soon explain to me. Now, on the far side of the ladders and ropes, Deidrah was mouthing Oppenheimer’s ear more and more ardently.

Bulky and torpid, Oppenheimer and the habitat’s other adult male didn’t fully take part in the life of the compound. They didn’t belong to any particular family. They were merely breeders—and their peripheral status mimicked the male role in the wild. There, in Asian mountains or lowland forests, adult males lurked at the edges of female-run domains. The females invited them in to serve sexually. The males remained—desirable, dispensable—until the females lost interest in them. Then they were dismissed, replaced. In his compounds, Wallen removed the breeders and introduced new males about every three years, the time it took for them to become irrelevant, for their charms to wane, for the frequency of their copulations—almost always female-initiated—to fade. In the wild they seemed to stay attractive only slightly longer.

“Rhesus females are very xenophobic when it comes to other females,” Wallen said. “Introduce a new female into the compound and she’ll be hounded until she dies. But when it comes to males, females have a bias toward novelty.”

With his pale muzzle and russet back, Oppenheimer loped off once more and Deidrah trailed him. A child of hers, less than a year old, hurried behind her. Wallen’s assistants adored Deidrah. They loved her sprigs of out-of-control hair; they loved her personality, the quiet dignity she emanated most of the time, if not at the moment; and they loved the devotion of her mothering. Last year, upheaval in the compound had left her and her children vulnerable. Horribly frightened, they latched on to her and wouldn’t let go. “Literally, she could barely get up and walk without being dragged down by her kids,” Amy Henry, an assistant, said. “One held on to her tail. They wouldn’t let her go. She accepted it all with grace. She knew it was her responsibility to reassure them that it was okay. She’s always been a low-key monkey. But she gets very excited when she gives birth. And she gets very attached. I watched her carry her daughter on her back for a long time, right up to when she had a new baby. Not all moms will do that.”

With hustling after Oppenheimer on her mind, though, maternal instinct was gone. She didn’t seem to see let alone know her baby; she kept leaving it alone, and it kept having to scoot after her. She positioned herself in front of Oppenheimer, crouched, and tapped a hand on the ground in a staccato rhythm. She tapped like this persistently, the rhesus equivalent of unbuckling a man’s belt. Yet her gesture contained a touch of hesitance. “She’s being careful, because all the females around her are higher ranked,” Wallen said. If they decided, for any reason, that they didn’t want her having sex with him, they and their families might tear and bite her to death.

Wallen’s realization, in the seventies, that rhesus females are the aggressors in sex had begun with a pattern he noticed in graduate school. At his university, pairs of adult monkeys—one female, one male—were observed in ten-by-eight-foot cages. At a lab in Britain whose work he read about, the cages were markedly smaller. On both sides of the ocean, the females had their ovaries removed; the scientists were tallying the copulations of the rhesus in the absence of ovarian hormones. And Wallen, who found himself contemplating the two sets of results against each other, was captivated by the fact that the couples in the tighter cages had a lot more sex. “So I pulled the literature on a range of similar tests that were done in different-sized cages, and the relationship was quite clear. In the smallest cages there was the most sex, in the largest ones there was the least, and the in-between ones had an in-between amount.”

Soon Wallen arrived at Yerkes, and, watching the rhesus in the center’s broad compounds—habitats whose size came closer to natural conditions—he developed his thinking about the way the tight confines in many experiments had helped to mold the accepted vision of monkey sexuality: lessening the female role and distorting the truth.

Put a male and female in a small cage, and no matter what the female’s hormonal state—no matter whether she had ovaries at all—the pair would have plenty of sex, in part, Wallen came to understand, because their proximity to each other mirrored the kind of stalking Deidrah was doing now. This sexual signaling, created by the cramped dimensions, stirred the males to mount. The males appeared to be the initiators of the species. But put rhesus in a less artificial situation, and sex depended almost completely on the female’s tracking, her ceaseless approaching, her lipping and stroking and belly-kissing and tap-tapping, her craving. Without her flood of ovulatory hormones, without the priming of her brain, copulation wasn’t going to occur.

Are females the main sex-hunters in most other monkey species? The answer isn’t yet known, Wallen said; not enough meticulous science has been done. Capuchins, tonkeans, pigtails—he named three types whose females are the stalkers. With their sweeping tails and ebony faces, female langurs initiate fervently. And among the massive orangutans, scenes like this were documented, for the first time, in the late eighties: males lying on their backs, showing off their erections to females, and waiting passively; and females closing in, mounting, pumping. As for bonobos, with their strangely parted hair and reputation for abandon, females avidly get sex going with males and with each other.

At last, with Deidrah tapping her crazed Morse code on the dirt, Oppenheimer reached out. Standing behind her, he set his hands on her hips. And suddenly she had what she sought, his swift thrusts. He pumped back and forth in a flurry. Then he paused, pulled out briefly, touched her flanks, and slid inside her again for another bout of thrusting. He humped and pulled out repeatedly. When he came, thighs quivering and eyes going fuzzy, she twisted, turned her face to his, smacked her lips at high speed, reached back to seize him, and yanked him violently forward.

Her fulfillment was short-lived. Within minutes, she was hounding him again. At other moments, she might have moved on to the other male. “She has sex,” Wallen said, about rhesus females on the whole, “and when he goes into his post-ejaculatory snooze, what does she do? She immediately gets up and goes off and finds another.” Tracking the action of the compound, he asked himself, as he had so many times, whether the libido in women has similar drive, and whether “because of social conventions and imperatives, women frequently don’t act on or even recognize the intensity of motivation that monkeys obey.” He answered, “I feel confident that this is true.”

Wallen didn’t mean to imply perfect correspondence between Deidrah and the average human female. The distinctions included the impact of ovulation, so much more subtle in women. He and his former doctoral student Heather Rupp had been trying to grasp the ways that women’s monthly hormones spur the neurotransmitters of desire. In one study, they had taken three groups of straight females and showed them hundreds of similar pornographic pictures—all featuring women with men—in three rounds, at different points in the women’s cycles. Again, Wallen and Rupp used viewing time as a measure of the subjects’ interest in the porn. One result was predictable: in the first round, the women who were near ovulation stared longer than the other subjects. But something else caught them by surprise. These same women, whose first round of porn came at mid-cycle, when testosterone and estrogen peaked, stayed riveted when they returned to the lab for their second and third rounds, as the month wore on and these hormones faded. The women whose initial viewing came during lower hormonal stretches didn’t become transfixed when they ovulated. They continued to be less moved. Maybe, Wallen thought, some kind of conditioned arousal or indifference took hold. In later rounds, he guessed, the subjects still unconsciously linked the surroundings of the lab, the equipment, the porn to their reaction to their first viewing.

“One lesson,” he said, “is that you don’t want a woman to form her first impression of you when she’s in the wrong menstrual phase. You’ll never recover.” He laughed.

Our conversation, on the platform above the compound, veered back to primatology, to the insights offered by our animal ancestors. He spoke about Deidrah’s abundance of lust and about its constraint in women—about a communal sense of danger, a half-conscious fear of societal disintegration, that lay behind the constraining. And as I listened, and afterward as I dwelled on things, I thought of the historic terrors, the carnal archetypes: of witches, whose evil “comes from carnal lust, which in women is insatiable,” according to the Christian doctrine of the Inquisition, “the mouth of the womb … never satisfied … wherefore for the sake of fulfilling their lusts they consort even with devils”; and of Eve, upon whose sinfulness all of Christianity is constructed, Eve, for whose evil the Son of God has to die, to sacrifice himself so that humanity can have a chance at redemption. This was the foundation, what lay beneath our culture’s primary religion; it was imbedded in our societal psyche. And I thought, too, of monogamy: our inchoate idea that monogamy girds against social chaos and collapse, and our notion—the desperate inversion of our terror—that the female libido is limited and that women are monogamy’s natural guardians. So we managed our fear.

Why, from beginnings in equally obscure academic publications, had parental investment theory come to permeate cultural assumptions over recent decades while monkey realities, ancestral facts, remained much less known? We embraced the science that soothed us, the science we wanted to hear.

“This organ serves a pleasure god,” Jim Pfaus said. He held a plastic replica of the human brain in his hands. A Van Dyke beard and a hoop earring adorned his animated face. His expertise as a neuroscientist and his Concordia University labs were called on by the major pharmaceutical companies whenever they wanted to test, in rats, a new drug that might serve as an aphrodisiac in women—none had worked out in women so far. His labs sat in a university basement. There he studied his rats in a variety of cages and, in a surgical theater, removed their brains—about as big as a person’s thumb from the middle knuckle to the tip.

Pfaus was obsessed with rat ways of seeing and feeling, learning and lusting, and when he wanted to investigate, say, exactly which set of neurons were sparked by a type of stimulation, by copulation-like prodding of the cervix or by the excitement of glimpsing a desirable male, one method was to provide a female rat with the experience, kill it, extract and freeze her brain, place the organ on a device resembling a miniature cold-cut slicer at a delicatessen, and shave off a specific, infinitesimally thin cross section. Peering at the slice through a microscope, he could pinpoint recent neural activity by noting the tiny black dots that told him where certain protein molecules—by-products of cell signaling—had been manufactured.

It was due to one woman that Pfaus—in his spare time the lead singer in a punk band called Mold—had been drawn to his specialty. Until the late seventies, scientists didn’t study desire in rat females; they didn’t see it; it didn’t exist: as with the rhesus, scientists fixated on what the rat female did in the act of sex, not what she did to get there. And what she did in the act was go into paralysis. She froze in a position called lordosis, with her spine slung low and her butt cocked high, so the male could penetrate. Rat intercourse required female rigor mortis. It was easy to understand the female as absolutely passive, without will, a vessel whose involuntary perfume pulled the male in. Similar scientific ignorance had pervaded our idea of females across the animal kingdom, with “receptivity” being the key term.

But then Martha McClintock, like Wallen, helped take scientists deeper. McClintock had begun to make herself famous years earlier while still an undergraduate at the all-women Wellesley College. She built a case that women living in close proximity responded to each other’s hormonal scents, causing the timing of their menstrual periods to converge, and her work was published in the revered journal Nature. Soon she was calling attention to female rat solicitations, to the female’s specific hops and darts, her head-pointings and prancings away—her methods of inciting the male to put his forepaws on her flanks; to set his paws into the whir of flank-patting that instantly immobilized her, as though by hypnosis; and to slide himself into her. While Pfaus and I talked about this in front of a bank of his Plexiglas cages, one of his females went further, as regularly happened. Dealing with a stolid, sexually uninterested male, she stood behind him, mounted his backside, and humped, as though to put ideas in his head. How, Pfaus marveled, could science not have noticed this?

McClintock documented, too, that the female, if her cage allowed her to evade her partner, made sure to slip away from him, constantly, in the midst of his pumping, so the sex didn’t end too quickly for her. Under any circumstances, in rat as in monkey sex, the animals attach, copulate, detach, and reattach repeatedly until the male ejaculates. The female rat, experiments showed, likes to prolong the process, to make it last longer than the male otherwise would. All of this, the solicitations and the preference for more drawn-out intercourse, suggested will and desire.

And McClintock established that by controlling the pace of mating, by getting the protracted stimulation and the rhythm that pleases her, the female can raise her odds of getting pregnant. She can raise them a lot. The extra thrusts, Pfaus said, cause contractions that aid sperm on their way into the uterus. And the deeper thrusts—for the male rat, forestalled from ejaculating, starts to pump harder—plies or jolts the cervix in a way that leads to a hormonal release that then helps to sustain a fertilized egg.

Pregnancy, though, is not an animal motivation, as McClintock and Pfaus, like Wallen with his monkeys, saw clearly. This was a critical point. Animal species have been designed by evolution to perpetuate themselves, to reproduce, but in the individual animal, it isn’t reproduction that impels. The rat does not think, I want to have a baby. Such planning is beyond her. The drive is for immediate reward, for pleasure. And the gratification has to be powerful enough to outweigh the expenditure of energy and the fear of injury from competitors or predators that might come with claiming it. It has to outweigh the terror of getting killed while you are lost in getting laid. The gratification of sex has to be extremely high.

Pfaus had been following the early light shone by McClintock. Partly because of her research, he saw that a rat’s brain was not merely a brain but a mind, that a rat’s psychological experience could be a revealing version of our own. An array of experiments, of brain shavings, of injections of chemicals that boosted or blocked one neurotransmitter or another, of observations of rats making choices in all sorts of carefully constructed habitats and scenarios, fed his knowledge. One line of studies building on McClintock’s work used a special cage with a Plexiglas divider down the middle. The divider had holes just big enough for a female rat—but not a male—to squeeze through. A female could determine the pace of sex by slipping from one side of the partition to the other and back again. “Female rats do what feels good. With the divider, she’s having better sex. Better vaginal and clitoral stimulation. Better cervical stimulation.” He described a study showing that intercourse stimulated the rat’s clitoris: a colleague had painted males with ink, then charted the inky areas on their mates. About orgasms, Pfaus couldn’t be sure whether female rats were having them; there was no easily measured sign, like ejaculation in males, to mark subjective explosion. But about pleasure and very intense desire, he was certain.

Proof ran like this: If, right after a rat finished a long-lasting session of mating, she was placed alone in another chamber, she would associate the new chamber with the sex she’d just had. Next, when given a choice between this new chamber and yet another, she would spend her time in the one linked with mating. She would make this choice even if the alternate chamber was set up to be much more inviting in other ways—even if the alternate space was dark, speaking to the nocturnal rat’s sense of safety, while the chamber linked with pleasure was brightly lit, screaming of mortal danger. Run the same test with a female who’d just had quick—unsatisfying—intercourse and she would, afterward, opt for the dark space.

One of Pfaus’s graduate students had lately performed and filmed a straightforward demonstration of desire—of motivation derived from the learned expectation of reward, just as desire develops in humans. Sitting with me in his office a few floors above his rat chambers, Pfaus played the video. The student picked up a female rat and, with a tiny brush, stroked the clitoris, which protruded from the genitalia like a little eraser head. She stroked a few times, then put the animal back down in her cage. Swiftly the creature poked her nose out of the open door. She clamped her teeth on the white sleeve of the student’s lab coat and tugged the woman’s hand inside the cage. The student brushed the rat’s clitoris again, set her down again. And again the rodent bit into the sleeve, pulling, communicating unmistakably what she craved. This went on and on and on.

As we watched, Pfaus mentioned the anatomical oversights that had squelched our understanding of the clitoris—rat and human—until a decade before. The organ has sizeable extensions, lying internally in the shape of bulbs and wings. These are positioned, in part, just behind the front wall of the vagina. Yet these nerve-rich formations had gone mostly unnoted by modern anatomists, who either left them undrawn or gave them no import. Science seemed almost to have willfully diminished the organ, cutting it metaphorically away. It was another lesson in the minimizing of women’s desire. Then, beginning in the late nineties, Helen O’Connell, an Australian urologist, detailed the organ’s sprawl, its many inches in reach. And she championed its sensitivity to pressure through the vaginal sheath—sensitivity perhaps responsible for vaginal climaxes and possibly the explanation for the fabled and debated G-spot. O’Connell was blunt about the averted eyes of her scientific predecessors. “It boils down,” she said, “to the idea that one sex is sexual and the other is reproductive.”

Now Pfaus pulled apart his plastic model of a human brain, his fingers in the folds. He spoke about the neurotransmitters that define eros for women as well as men. The libido is, in a sense, two-tiered. There’s the lower realm, in which hormones rise up from the ovaries and adrenal glands, float along the bloodstream to the brain, and fuel the production of the brain’s neurotransmitters. How exactly this fueling happens is still a mystery; so is the quantity of fuel needed to keep the production line running well. The higher realm is the brain itself, the domain of the neurotransmitters. These biochemicals, not the lowly hormones, form the essence of lust.

Dopamine—its atoms arranged like an antennaed head with a spikey tail—is, in a way, the molecular embodiment of desire, its main chemical carrier. It isn’t only that; it speeds through a multitude of the brain’s subregions and exists in infinite relationships with other neurotransmitters and has all sorts of effects, from motor control (the trembling and sluggishness of Parkinson’s patients stem from a shortage of dopamine) to memory. But dopamine is the substance of lust. And by way of his mini deli slicer, Pfaus had narrowed his sights on two tiny territories at the brain’s primal core, the medial preoptic area and the ventral tegmental area. These were the heart of dopamine’s sexual system, he said, “the ground zero of desire.”

From this primitive epicenter, dopamine radiates outward. “A dopamine rush is a lust-pleasure,” Pfaus continued. “It’s a heightening of everything. It’s smelling a lover up close—a woman inhaling that T-shirt. It’s starting to screw; it’s wanting to have; it’s wanting more.”

Yet for the excitement of dopamine to fix on an object, for it to be felt as desire rather than as a splintering into attentional chaos, it has to work in balance with other neurotransmitters. Serotonin plays an indispensable part. Unlike dopamine’s keen drive, he said, serotonin dampens. Unlike dopamine’s lust, serotonin instills satiation. Flood female rats with antidepressants—like the selective serotonin reuptake inhibitors, the SSRIs—that bolster serotonin, and the females will spend less time courting males. They will also bend their spines less fully, raising their butts less completely, to accommodate the males they do mate with.

It was important, Pfaus emphasized, to understand serotonin’s virtues. They go beyond keeping depression at bay. The neurotransmitter also allows the brain’s frontal lobe, more precisely the prefrontal cortex, the region of planning and self-control, to communicate effectively within the organ, to exert what’s known as executive function. Serotonin reduces urgent need and impulse; it facilitates sensible thoughts and orderly actions. The problem, though, is that if serotonin is too strong in relation to dopamine, a woman making love is likely to find herself thinking about the next day’s schedule rather than feeling overtaken by sensation and craving. But with serotonin and dopamine in the right balance, erotic energy will be neither displaced by tomorrow’s to-do list nor permitted to fracture into chaos. With the frontal lobe and the libidinous core in harmony, desire can have both form and force.

For all the agility of his deli slicer, which could be set to the width of a micron, Pfaus was nowhere near to completely capturing the interplay of neurotransmitters. But a third type of transmitter essential to eros, he said, are the opioids, which surge with orgasm and also spike in tandem with dopamine’s drive, so that glimpsing a lover’s muscular chest or reading a paragraph of erotica offer a minor wave of opioid bliss. Describing this pleasure, he talked about the opioids’ most potent varieties, the products of poppies: morphine, heroin. Send these drugs into the brain and satisfaction is so thorough—so much stronger than serotonin’s well-being—that inertia takes hold. Both the executive region and the lustful center are quelled; direction and drive are nullified. In the less potent forms supplied by orgasm, the opioid rush lulls to lesser degrees. Meanwhile, a paradoxical process kicks in. Even while the opioids are quieting motivation, they are preparing the brain to be motivated again by somehow stoking the dopamine system. Orgasms simultaneously subdue the brain and teach it to seek more climaxes. Maybe even regardless of orgasm—for Pfaus couldn’t be sure his female rats were climaxing—he saw the power of opioid bliss in his lab. Infuse female rats with a chemical that blocks this ecstasy, and they lose their desire to have sex at all.

Pfaus, whose hoop earring cast a gleam, whose mind bounced always between rodents and humans, translated this finding into a few words of advice: men had better perform; they’d better learn, they’d better deliver, and they’d better keep on delivering.

Not that this would solve men’s problems, not that it should calm their worries. One morning he lectured his undergraduates on the Coolidge effect, a standard in sexuality textbooks, an expression of what Pfaus scorned as evolutionary psychology’s “shtick.” The Coolidge effect comes from a tale that goes like this: One day President Coolidge and his wife were visiting an experimental government farm. They took separate tours. When Mrs. Coolidge came to the chicken yard she noticed the rooster’s frequent mating and asked the attendant how often this went on. “Dozens of times each day,” he informed her, to which she replied, “Please tell that to the president when he comes by.” The attendant did as she requested when the president arrived. “Same hen every time?” the president asked. “Oh, no,” the man answered, “different hen every time.” And the president said, “Please tell that to Mrs. Coolidge.”

The tale is used to hammer home the principle that male lust feeds on multiple partners. Pfaus mocked the faith that this is somehow less so for females. Rodent females, he informed his undergrads, do more hopping and darting to score with new mates. And they dip their spines deeper, so the new male has an easier time thrusting in.

During one of our talks, Pfaus swerved from the evidence he’d accumulated; he careened down a road of speculation. “When this generation of young people is fully studied,” he said, words gathering speed, “we’re going to see more supposedly male-like behavior, more women picking up men, more women getting laid and leaving, having sex without waiting to bond, more girls up in their rooms at their computers clicking on porn and masturbating before they get started on their homework.”

It wasn’t clear which age group he was thinking about, whether he meant girls who were now twelve or women who were now twenty-four, and it wasn’t clear how he explained the unfettering he believed was underway, though it seemed to have partly to do with the Internet. Were there any concrete signs, I wondered, that the trend he imagined was real? Were girls and women staring more and more at the X-rated? Was their porn-surfing nearing that of men? There were only scattered answers, slivers of evidence. The most credible came from Nielsen, the consumer tracking company, in a report that one in three online porn users was female—four years earlier, the figure had been one in four. And porn-addiction counselors were quoted in the press saying that their ratios of female clients were rising. Yet the most vivid clue was probably James Deen’s fan base.

Deen—who’d chosen his name and its spelling himself—was a porn star who’d shot two thousand scenes over the last eight years, scenes in which a delivery man is asked inside for a blow job, in which a principal teaches a lesson to a new high school teacher, in which a chained and gagged blonde submits or a MILF has her way, scenes made, like most of the films produced by the thirteen-billion-dollar-a-year porn industry, with men in mind. But the scenes had caught on among teenage girls. Teens and young women seemed to make up most of his tens of thousands of Twitter followers. They watched him on PornHub and Brazzers and Kink.com; they traded his images, set their computers to pick up any mention of his name, sent him proposals of marriage. A profile on Nightline—“the young man your teenage girl may be secretly watching,” the introduction intoned, “a porn star for the Facebook generation”—added to the craze. GQ, the New York Observer, the Guardian in England swarmed next. Some fans said they were attracted by his boy-next-door looks, some by the way he held a woman’s eyes amid doing everything else, but along with his slender build and the possibility that he gave slightly more eye contact than the average porn stud, the basics were the basics: a maximally sized erection, a minimum of dialogue, a dose of violence (“I’ve been into rough sex pretty much my whole life,” he told one interviewer, “so I’m not, like, bad at it”), lots of female moaning, many genital close-ups.

Like Deen’s popularity, Suki Dunham’s nascent success as an entrepreneur pointed to changes taking place. In her case, the changes ranged over age groups. In a New Hampshire town of four thousand, in a farmhouse bordered by a white picket fence, with a tree house out back for her two kids, Dunham designed state-of-the-art vibrators like the Freestyle and the Club Vibe 2.OH.

The predecessors to her devices had been around for over a century—initially as aids to doctors and nurses who believed they needed to massage patients to “paroxysm” as a cure for hysteria—but during the last few decades the percentage of women saying they’ve used a vibrator has gone from one to over fifty, and a few years ago vibrators appeared on the shelves at Walmart, at CVS, at Duane Reade. Trojan spotted an opportunity, entered the market, advertised its Tri-Phoria on TV, and watched sales leap in a period of cataclysmic economic decline. Durex, another condom maker, did the same and had the same results. And Dunham, who grew up in a coal-mining town in Pennsylvania, the daughter of a man who ran a small excavation outfit, was developing a high-end niche.

Dunham, who has an eager, thin-lipped smile, had worked at Apple for nine years, marketing iMacs. One Christmas in her mid-thirties, she received in her fireplace stocking an iPod and a vibrator from her husband, who traveled a great deal on business. Using the two devices together started her thinking, and now she had a warehouse packed with merchandise. She was shipping to thirty countries and had just begun teaming with a reality TV star who was turning the products and Dunham herself into a regular part of the show. Dunham’s company sold sleekly curved vibrators, aggressively bifurcated vibrators, discreetly streamlined vibrators, and an app that let the user program a vibrator to pulse and tremble to the rhythm of an iPod’s music. The newest item, the bullet-shaped 2.OH, slipped into a bullet-shaped pocket stitched into a thong. The 2.OH massaged, at an array of intensities, to the music of a club or party. It had enough charge to last three hours.

With females hopping and darting in front of us, Pfaus asked, “Why do we have Pandora’s box—why have we boxed in women’s sexuality? Why do we keep women’s desire relatively repressed? We men are afraid that if we open the box, open her control, we’re opening ourselves to being cuckolded. We’re afraid of what’s inside.”

He laughed over a memory of mine: not too long ago, porn on cable TV in New York had, by law, included a blue dot. Always, the dot covered the male member. Women’s bodies were thoroughly exposed, yet the dot floated wherever the penis went.

And I thought, as well, of trips I’d made in other parts of my writing life, trips to places where the blue dot took other, not so comical forms. Once, in a remote village in northern Kenya, I’d asked a group of Samburu men why their culture practiced clitoridectomy. They answered matter-of-factly, “So our wives will be faithful.”

Sometime later I spoke again with Chivers. She’d been designing a new experiment that would use subliminal images as another means to tunnel beneath consciousness and perhaps beyond culture. She outlined the study, then said that she’d been thinking about the scene in her college lecture hall twenty years before, about the sound of “Eeew,” about that fleeting, unforgettable, half-funny syllable as an expression of a history and prehistory of “all kinds of prohibitions and restrictive perspectives on female sexuality.” Suddenly her voice leapt: “Look at all the barriers! Look at all the obstacles! But that isn’t what amazes me.”

She was a fastidious scientist who chose to surround herself with surfaces of barely adorned cinder block, to spend her days in an almost monk-like cell, to avoid pronouncements, to let her data speak for itself. Now, though, she ignored the scientific restraints. “Those barriers are a testament to the power of the drive itself. It’s a pretty incredible testament. Because the drive must be so strong to override all of that.”