In the spring of 1978, a professor at Florida State University gave the students in his seminar on experimental social psychology an unusual assignment. For the next few weeks, they were to approach undergraduates of the opposite sex and compliment them: “I’ve been noticing you around campus lately and find you very attractive.” Then they would ask one of the following questions:

(a) “Would you go out with me tonight?”

(b) “Would you come over to my apartment tonight?”

(c) “Would you go to bed with me tonight?

Roughly equal numbers of men and women on the FSU campus accepted invitations for dates from strangers: in response to question (a), 50 percent of men and 56 percent of women said yes. However, the responses to (b) revealed a dramatic split, which followed gender lines in exactly the manner the professor had predicted: while 69 percent of men were willing to meet a female stranger at her apartment, only 6 percent of women would meet a male at his. And while 75 percent of the male students approached said they were game for casual sex, not one female did.

The professor, whose name was Russell D. Clark III, never recounted how many actual hookups (or hurt feelings) resulted from the experiment. He did, however, develop a novel approach to analyze his data. Clark argued that men and women reacted differently to being propositioned in part because they had evolved differently. Contemporary attitudes toward sex were not the product of social norms; they constituted adaptations. Nature selected swagger in men and prudishness in women over eons, just as it favored gazelles with limbs quick enough to flee predators and birds with beaks sharp enough to break seeds: such traits increased the fitness of our ancestors, their ability to survive and reproduce themselves.

The first colleagues to whom Clark sent his article dismissed it. “This paper should be rejected without possibility of being submitted to any scholarly journal,” one peer reviewer wrote. “If Cosmopolitan won’t print it…then Penthouse Forum might.” Clark had given up on finding a publisher when, in 1980, he met Elaine Hatfield, a psychology professor at the University of Hawaii who shared his research agenda and convinced him that it was worth fighting for. In the spring of 1982, Clark and Hatfield repeated the FSU study and obtained almost identical results. Still, fellow scientists were skeptical. “Who cares what the result is to such a silly question,” read one rejection letter the pair received in 1984. “I mean, who cares other than Redbook, Mademoiselle, Glamour, or Self—all of which would cream their jeans to get hold of this study.”

It wasn’t until July 1988 that the Journal of Psychology & Human Sexuality accepted Clark and Hatfield’s article. When it appeared in 1989, “Gender Differences in Receptivity to Sexual Offers” passed mostly unnoticed. Among the few of their colleagues who did take note, some pointed out that it used evolution to excuse chauvinistic behaviors. “The devil (or Darwin) made me do it,” joked one feminist critic. But Clark and Hatfield would have the last laugh: their claim that the insights of evolutionary biology could be used to cast light on the human mind and human behavior became the first principle of a new field that took off in the 1990s. Dubbed “evolutionary psychology” (“ev psych” or “EP” for short), it has gained an ever-stronger hold on the popular imagination.

Ironically, the haters who mocked “Gender Differences in Receptivity to Sexual Offers” as fare suitable only for women’s magazines also anticipated the terms of its wild success. Within the academy, many of EP’s methods have been questioned and even discredited. Yet even as academics continue to point out its flaws, the mainstream media have increasingly accepted evolutionary psychology as a mode of explaining human behavior. What we want to know is: Why? How has the kind of claim that made Clark the butt of bad academic jokes for a decade become so widely disseminated that by 2014 it sounds obvious, even banal?

In order to understand why there is such an insatiable appetite for this kind of explanation—why even the readers of center-left publications like The New York Times are willing to accept the idea that gender roles and relations are hardwired—we need to investigate how evolutionary psychology itself evolved. We propose that its popular success has nothing to do with how plausibly its proponents describe the struggle to survive on the plains of the Pleistocene Era. What it does reflect is the brutally competitive economic environment today. Evolutionary psychology may just provide an ideal theory of love for the precarious age in which we live.

It makes sense that psychologists would want to use evolutionary theory to interpret human behavior. Darwin himself argued that the processes of natural selection that he described in On the Origin of Species (1859) had shaped our minds as well as our bodies. “The individuals who were the most sagacious, who invented and used the best weapons or traps, and who were best able to defend themselves, would rear the greatest number of offspring,” he wrote in The Descent of Man (1871). According to Darwin, our mental and moral powers were simply traits that we inherited because our ancestors who possessed them were more likely to make it, and to mate, than were their brethren.

Scholars have tried to apply his theories to human society ever since. The philosopher Herbert Spencer famously argued that competition among men for survival was not only inevitable but good. His 1864 book Principles of Biology glossed On the Origin of Species as proof that “survival of the fittest” was the innate law of all things. In retrospect, it is easy to recognize his theory of nature as an unacknowledged description of nineteenth-century England—a country cast into upheaval by rapid industrialization and urbanization, which was jostling with France to gain control of the largest empire in history. Victorians troubled by urban poverty now had a reassuring explanation for the suffering they saw in the streets of London and Liverpool. It was only natural that the factory owner survived, thrived and reproduced, while his laborers suffered illness, injury and early death. It was only natural that colonial regimes brutally extracted resources from Asians and Africans unable to resist their guns. Those who survived at the expense of others were simply proving their own fitness, and their enemies’ weakness.

When he hailed natural selection as a force driving the improvement of the human species, Spencer conferred value on a process that Darwin had merely described. He saw evolution as a kind of market competition that produced the “best” creatures, just as classical economists believed the free market produced superior products and services. Over the course of the twentieth century, evolutionary science would continue to co-evolve with theories of capitalism: economic theory influenced evolutionary theory, and vice versa.

After World War II, the idea that human history was a story of progress seemed less plausible. The term “social Darwinism,” which critics of Spencer had coined to attack his work in the 1870s, was revived in the 1940s to explain the intellectual origins of Nazi eugenics. At the same time, breakthroughs in genetics were changing the way scientists understood evolution—and would change how public intellectuals attempted to apply it to society.

On the Origin of Species had asserted that nature selects biological traits based on the ability of individuals to survive and procreate. But Darwin could not account for how, exactly, parents passed down traits, or how their children came to express what they received in their bodies and behaviors. The revelation that genes carried this information transformed the understanding of natural selection. While Darwin had focused on individual survival, his twentieth-century successors studied gene survival. This fusion of evolutionary theory with genetics turned the eye of science and social theory on reproduction. Selection was no longer a matter of struggle, but a matter of sex.

The neo-Darwinians measured fitness not only in terms of how likely a person was to survive, but also how likely she was to pass on her genes. A spinster who lived until the age of 100, but did not have a child, was less genetically influential than the teenage cad who knocked up his sweetheart and promptly died in a car crash. Some theorists further expanded their idea of “fitness” to incorporate the idea of kin selection. An individual’s genetic material survives if he or she reproduces, but it also survives if his or her siblings do. Therefore, there are evolutionary incentives to help one’s family and even one’s in-laws thrive.

In 1975, the Harvard naturalist E.O. Wilson published Sociobiology: The New Synthesis, a book that heralded a new movement. Wilson became fascinated with how the members of insect colonies cooperated with one another, even when it seemed to go against their own individual interests. In Sociobiology, he argued that such cooperative behaviors were genetically inherited in a wide range of species.

In retrospect, the shift from “survival of the fittest” to sociobiology clearly seems to mirror dramatic changes that were taking place in the economy. Wilson updated Spencer’s analogy between biology and capitalism for the era of the corporate drone. While business self-help guru Dale Carnegie taught Americans that they could get ahead by “winning friends and influencing people,” sociobiologists argued that charisma and social savvy had trumped brute force among our prehistoric ancestors. Humans, according to new theories of “inclusive fitness,” spread their genes most effectively by gaining allies and lovers.

Evolutionary theory’s new emphasis on sexual selection made sense in a consumer economy in which desire—for products, for clothes, for rock singers and movie stars—ruled the market. Evolution no longer explained the victory of the fiercest fighters. The survival of the fittest had become the survival of the sexiest.

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Not everyone bought it. many scientists rejected sociobiology for its lack of methodological rigor. The Harvard paleontologist Stephen Jay Gould described Wilson’s work as a series of Just So Stories, after Rudyard Kipling’s volume fancifully explaining phenomena like “How the Tiger Got Its Stripes.” Gould’s point was that the new discipline created fictional origin myths, projecting modern ideas onto an imaginary past. Without hard evidence of how our prehistoric ancestors met and mated, how could scientists make claims about the evolutionary basis of our behavior? Gould feared that sociobiology would give conservatives ammunition to argue that a sexist, racist, xenophobic status quo was natural, and therefore could not be changed.

By the early 1980s, sociobiology desperately needed a rebrand. Evolutionary psychology rose to the task. The founders of the discipline hoped to establish a more rigorous method for making claims about our evolved nature. First came Leda Cosmides and John Tooby—a husband-and-wife team who hold PhDs in psychology and anthropology, respectively. Cosmides and Tooby proposed that Wilson’s sociobiology had lacked a concrete, material link between biology and social life. Instead, it treated all of social behavior as one complex “organ.”

Cosmides and Tooby proposed instead that the mind was made up of hundreds, even thousands, of “organs” that they called “modules,” and that each of these had evolved independently of the others. Every person, they claimed, is born with something like a Swiss Army knife in the head, a set of cognitive tools that nature selected because our ancestors found them advantageous. Suddenly, adaptationist thinkers could imagine various behaviors as having evolved individually, in response to specific challenges that their environment presented. Poisonous snakes? Cosmides and Tooby propose that the brain naturally developed a snake-fear module. Con artists prowling the bushveld? There’s a cheat-detection module for that.

Another husband-and-wife team, Margo Wilson and Martin Daly, hoped that they could find empirical evidence that certain behaviors were hardcoded into the brain. They set about gathering data on infanticide from nonprofit and social-service organizations in order to prove Wilson’s intuitions about kin selection. Their findings showed that stepparents neglect or kill their stepchildren at a much higher rate than biological parents neglect or kill blood descendants. Voilà!—a kin-selection module.

Throughout the 1980s, Randy Thornhill and his ex-wife Nancy Wilmsen Thornhill published several articles on rape in the new journal Ethology and Sociobiology. The Thornhills argued that rape conferred a reproductive advantage on men who otherwise couldn’t secure mates. They also conducted empirical studies with rape victims and used the findings to argue that their psychological pain was an adaptive response—one that, in effect, teaches victims to stop asking for it. The article about propositioning undergrads on the FSU quad, which Russell Clark and Elaine Hatfield struggled ten years to publish, seems tame in comparison.

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An entire discipline now existed to tell the cold, hard truths about human nature, and the public was ready to listen. In the early 1990s, evolutionary psychology went mainstream: popular-science writers discovered that their readers had an insatiable appetite for evolutionary explanations of human behavior. Prominent scientists in the field, including Steven Pinker and David Buss, wrote trade books explaining the evolutionary theory of the mind to a popular audience; Robert Wright’s The Moral Animal: Evolutionary Psychology and Everyday Life was named one of The New York Times’s “Best Books of 1994.” Pinker’s lecture class became one of the most popular at Harvard. The University of California, Santa Barbara, and the University of Texas, started laboratories to train the next generation of acolytes. Buss wrote an early ev-psych textbook in 1999.

Given the preponderance of couples at the forefront, and their desire to win attention (and thus funding), it may have been inevitable that the new discipline would be sex-crazed. Sex and gender differences became evolutionary psychology’s most important topics. EP had inherited one major insight from sociobiology: it was not enough to talk about how or why individuals survived. In order to influence the course of evolution, we have to reproduce. Researchers started proposing that various mental modules would have conferred “reproductive advantage” on our ancestors. But men and women have different stakes in reproduction; therefore, their Swiss Army knife brains evolved to contain different tools.

Evolutionary psychologists argued, for example, that women have a mental module that makes them attracted to older, high-status males who have the resources and authority to protect their young, while men have a module that makes them attracted to young females with a lifetime of childbearing ahead of them. The popular press ate it up. A 1996 Newsweek cover story, “The Biology of Beauty,” featured cameos from all the major EP players: Randy Thornhill, Donald Symons, Helen Fisher. Meanwhile, New York Times science reporter Natalie Angier took on the sex-and-science beat, explaining the newest evolutionary theory to readers.

Within the academy, doubts about evolutionary psychology abounded. A wide range of scholars contributed to a 2000 anthology called Alas, Poor Darwin: Arguments Against Evolutionary Psychology. In 2005, the philosopher David Buller wrote a book called Adapting Minds that captured the growing discomfort with EP among historians of science. Both historians and scientists criticized evolutionary psychologists for making broad claims about what humans desired in a prehistoric past to which we have very little access. Adaptationist narratives rarely qualify as scientific hypotheses, quite simply because they are impossible to prove right or wrong. Evolutionary psychology does draw on empirical data and laboratory studies, and those data are falsifiable. But the adaptationist explanations that evolutionary psychologists offer are not. We can know what today’s college students say they want in a mate, but it’s impossible to know what our Pleistocene ancestors were after by reading our own preferences backward.

Despite these critiques, the popularity of evolutionary psychology in mainstream media has only increased with the rise of Internet journalism throughout the new millennium. The headline of the typical story on evolutionary psychology entices us with a question. Usually it’s a question that the writer seems to imagine we have scratched our heads about—or wrung our hands over—before: “Why Do Men and Women Talk Differently?” “Why Do Men Cheat?” “Why Do Men Find Blondes So Very Attractive?” “Why Do Men Show Off Around Women?” “Why Do Nice Girls Fall for Bad Boys?” “Why Do Women All Seem to Want Taller Men?” But some headlines are more frivolous: “Can Evolution Explain High Heels?” (Spoiler alert: it can!) Still others pose questions that we never thought to ask: “Why Do Women Have Sex?”

In each case, we are presumed to believe in the phenomenon under analysis already. All we require is an explanation, a story that tells us why we are the way we are. Ultimately, the explanation is always the same: evolution—i.e, reproductive advantage. Click on one of these stories and you will find two things: first, the results of a recent psychological study that verifies an observation about a common human behavior; and second, an evolutionary explanation for why that behavior was advantageous for our ancestors. Because their standard operating procedure is to begin from behaviors that they perceive as universal (despite the fact that blond hair, for example, could hardly be considered universally valorized), evolutionary psychologists tend to confirm received wisdom. Many EP studies tautologically assert that widely held social values are… well, widely held. Study finds that most men are attracted to women who are deemed conventionally attractive by society!

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The articles about one 2011 study, whose results spread recently like wildfire, are exemplary. On November 18, 2013, The New York Times picked up an article from the journal Proceedings B on female aggression. The post that ran on the “Findings” blog, “A Cold War Fought by Women,” begins with an observation that we all know to be self-evident: women compete with one another. Now, the Times reported, researchers have found hard proof.

In 2011, a Canadian professor of psychology named Tracy Vaillancourt and her colleagues recruited groups of young women from a university in southern Ontario, telling them that they were to participate in a study on female conflict. They were, in fact, part of a setup—one staged to reveal their bitchiness. Vaillancourt exposed this bitchiness with the help of an undercover collaborator whom the study calls the “Sexy Confederate,” another young woman who had been selected using scientific criteria for “sexiness.” The scientists equipped her with two disguises: one normal outfit and one “promiscuous” outfit. Then they gave her her mission: to wander into rooms that contained pairs of female test subjects and ask them whether they knew where “the experimenter” was.

As expected, when the Sexy Confederate entered a room wearing her miniskirt and deep V-neck, the unwitting subjects said mean things—both to her face and in her absence. When she wore “normal” clothes, they barely noticed her. Vaillancourt used evolutionary theory to explain these reactions. “Sex is coveted by men,” she informed the Times. “Accordingly, women limit access as a way of maintaining advantage in the negotiation of this resource. Women who make sex too readily available compromise the power-holding position of the group, which is why many women are particularly intolerant of women who are, or seem to be, promiscuous.” The results could easily have been interpreted to mean that the test subjects live in a culture of “slut-shaming,” which punishes women for open displays of sexuality. But the Times story concluded otherwise: in the words of reporter John Tierney, “there’s no longer any scientific doubt that both sexes are in it to win it.”

Three weeks before publishing his story, Tierney appeared with Vaillancourt on CBS News. The pair offered a winning image of the co-dependence between a social-sciences expert and her popular translator. The response around the web was more divided. Bloomberg Businessweek and New York magazine’s “The Cut” simply paraphrased the Times article, taking it at its word. Jezebel ran a snarky takedown that was viewed by nearly 20,000 people. A longer and more scientifically grounded essay appeared in The Atlantic and was shared online more than 14,000 times. But however they got there, hundreds of thousands of people viewed Tierney’s article. Whether or not his claim that women are “in it to win it” is true, it took on a kind of reality online.

Why do we swallow this clickbait? Stories about sexy science reliably draw readers because they address questions about our identities and intimate lives that matter deeply to almost everyone. We live in a time when people of every political stripe stress about how the changing economy is changing gender roles and relations. Even the most retrograde EP stories about gender and sex can offer reassurance. EP comforts women who feel disappointed that they still do not have it all, by insisting that no feminist movement could have changed things. Nor are our everyday failures our fault. Your boyfriend or husband isn’t being selfish when he forgets to pick up the dry cleaning; he evolved not to do laundry! At the same time, EP tells conservatives anxious about the disappearance of traditional gender roles that they don’t have much to worry about, because the fundamental facts of how we interact are deeply programmed.

Yet like every previous attempt to apply evolutionary science to social life, evolutionary psychology is far less convincing as a description of unchanging human nature than it is as a sketch of contemporary capitalism. Spencer and his followers read Darwin’s On the Origin of Species as a justification for unregulated market competition and colonization. Wilson celebrated cooperation among insects and other creatures as men in gray flannel suits kept postwar American corporations humming. In this light, the Pleistocene hunter-gatherers who are the protagonists of EP start to look like people we know: freelancers and interns, working on temporary contracts and without benefits.

The scholars who created EP—Cosmides, Tooby, Symonds and others—argued that human evolution stopped at the end of the Pleistocene Era: with the rise of agriculture, they reasoned, humans stopped competing so much for resources. In this age of economic strife, we too are less apt to think of humans as naturally agrarian creatures. The office worker once resembled the farmer: he worked the same field his whole life, according to stable rhythms. Today’s ideal worker, by contrast, is always on the move. She scans the horizon for her next gig, and when she sees competition, she goes right for the jugular. Is it any accident that so-called “Paleo diets” have taken off during the same years as pop EP? Our own brutish world resembles the one EP depicts, and so we are increasingly eager to hear that our savageness is only natural.

What we now believe about our genes, we also believe about our search engines and consumer goods: that they gain value and utility through massive processes of selection. Our technologies succeed and fail and transform themselves based on the unorchestrated coordination of millions of consumer desires. Google and Facebook use our search histories and shopping habits to refine their algorithms. If enough consumers find the iPhone sexy, we know the iPhone will succeed. And it will pass along certain of its most advantageous traits—like glass touchscreens and wireless access—to its technological heirs. It is as if our ever-evolving tech devices were living beings, and we humans the nature that selects among their myriad features.

It’s not too much of a stretch, then, for us to imagine our species as evolving and changing on the basis of our individual sexiness, our popularity, our market appeal. Popular EP preaches the wisdom of the genetic market: that selection made us strong, clever and socially adept. It makes a lot of seemingly random interactions add up to a kind of mass intelligence.

Humans tend to think of their lives as narratives; some evolutionary psychologists even say that we have evolved to be that way. But now more than ever, we are materially and spiritually dependent on institutions that work by algorithm: the market, the virus, the search engine. In this context, evolutionary psychology helps make the random seem less random. Its appeal may be precisely that it turns impersonal processes of selection into coherent stories. But EP has not gotten us any closer to understanding “human nature.” Instead, its provocations about gender have distracted us from what is truly interesting—and radical—about Darwin.

Several EP scholars argue that human nature was fixed in the Pleistocene Era, that modern culture is merely a flimsy cover for our cave-dweller minds. But a great deal of evidence suggests that evolution occurs at a much faster rate than evolutionary psychologists think. And in any event, not all of the genes we inherit will express themselves. New research on “gene expression” is exploring the environmental factors that “switch on” genes. Even if there were a “rape gene,” many factors would limit its expression, and a truly anti-rape culture might eliminate it for good.

Many academics have criticized EP for lacking a healthy—and scientific—skepticism. But it also lacks a humanistic approach, attentive to the subtlety and nuance of human relationships. Assertions about how we are “pre-programmed” shut down our most interesting conversations about gender roles and sexual relations. Our desire to speculate about human nature may be our most distinctive feature. Along with one other constant: whether by nature or nurture, human beings can change, are changing, and will continue to change.