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Evolutionary Psych Strikes Back

New theories hold gender is in our genes.

Experts agree that men and women have more than just biological differences. But what does that mean for society? Culture? Family? Work? With primarily women researchers on one side and men on the other, the battle of the sexes rages on.

It's boys against girls yet again. Schoolyard taunting, but the stakes are higher. In place of spitballs, though, this time they're hurling serious research at one another.

The latest skirmish in the war between the sexes has flared up between psychologists studying the origins of gender differences. Research has shown that despite feminist advancements, gender differences persist. The question no longer is whether there are differences between the sexes but what to make of them.

On one side are those who claim that it is evolution and biology that make us significantly different, and that no amount of feminist agitation will change that. Men will continue to be philandering, non-nurturing and sex-focused, and women will continue to be mothering keepers-of-the-hearth. On the other side are those who claim there's a lot more variation to our gender roles. Society, they say, and not our genes, determines how we react to our biological course. Change, this latter group says, is possible and evident.

So to what extent does biology, despite feminist objections, mean destiny? How willingly does our biology respond to our environment? And even if biology plays a role, how much of the male/female split is nonetheless reinforced by the culture we live in? During this era of great change in women's and men's roles--as we work out collectively who we will be in the coming generations--we need to know: Where do these differences come from and where might they go?

No little amount of rancor has been stirred up in the attempt to answer these questions, in no small measure because the psychologists themselves who are studying the origins of gender differences seem divided along gender lines. In undertones, some researchers suggest that all the evolutionary psychologists (EPs) are men, and those with theories about more varied etiology are women. Some accuse male EPs of seeing feminists as "the enemy," while others accuse female researchers of dismissing evolutionary theories which seem to reinforce male dominance out of hand. Each side tries to take the scientific high ground, pointing to the gender split with a cough or a sly look. They mean that, perhaps, these details are no accident: Maybe men, who still hold positions of relatively high status in American society, are promoting theories that maintain the patriarchal status quo; women, some of them self-described feminists, see a science that allows for more change.

This gender split raises important questions about the current research. Each of these social scientists has looked at hundreds of studies to support his or her claims. There's relevant data from cultures on every continent, from cultures in every era dating back hundreds of thousands of years, and from every species from chimps to phalaropes (a small shorebird) to mice. Faced with thousands of studies, each theorist must look selectively at the data. And if theory drives research, we need to ask how much of the narratives of human development we read come from the way the personal narratives of the individual researchers color their world view.

The latest round of hostilities in this gendered war started in the mid-1990s, when a group of evolutionary psychologists began publishing research that looked at the origins of gender differences through Darwin's eyes. These EPs claimed (and continue to claim) that differences between the sexes do exist and that, try as we might, we can't change them. (That's the spark in the political tinder-box.) Whether in pre-modern Africa or current-day America, they say, gender-specific skills come from distinct psychological mechanisms that can be traced back directly and very nearly wholly to the Darwinian principle of sexual selection. In other words, it's in our genes.

The narrative of sexual selection goes something like this: In the mating and survival game, we all have a choice. One option, as David Geary, Ph.D., of the University of Missouri-Columbia puts it, "is to take all your energy and focus it on competing to get as many mates as you can. The other option is to have few mates and invest your reproductive energies on raising [offspring]." Men--who for biological reasons can have as many children as women they impregnate--follow the former path. Women, bound to their offspring by pregnancy and nursing, follow the latter.

True in many species, this drama is complicated among humans because many men parent their children, albeit not as much as women. Women, for their part, will compete for those men who invest in their children, thus raising their value. While the impact of these elements varies from one culture to the next, the pattern remains: Women invest in children more than men, and men, all other things being equal, prefer more sexual partners than do women.

Given these facts, the EPs suggest, men will naturally be inclined to pursue multiple partners. Their efforts, from an evolutionary point of view, will be put into finding a beautiful woman (genetically more appealing), finding as many partners as possible, and honing their physical skills in order to battle with other men for desirable women. Emotional skills that might lead to long-term relationships, in this view, have little role. Women, on the other hand, will pursue men who are more likely to stick around the morning after and help provide the food and protection mother and child will need to survive.

Sounds a lot like gender stereotypes today: a species of aggressive philandering men and nurturing, monogamous women. (Much cited research to bolster this view by David Buss, Ph.D., a leader in this field at the University of Michigan, found that male college students who were offered the chance to sleep with a beautiful stranger that night, were more likely than their female counterparts to say yes.)

The situation may vary among cultures but, says Geary, culture will never change the fact that men can potentially reproduce more frequently than women. "It will always lead to some level of conflict of interest between men and women. Women want men to invest in their kids and them, and by doing so, men lose the opportunity to have multiple mates." And, he adds, there is no culture in which there is equality between men and women in childcare. "Women," he adds, "hate to hear that."

He's right. Women do hate to hear that. Not only women of the general public, but women researchers as well. Riled psychologists, many of them women, sat up in alarm when the evolutionary psychology theories started snowballing in academic journals and in the popular press as well. Articles appeared, television shows hosted EP spokespersons. Social conservatives started using the "biological" evidence of gender differences to claim validity for the women-as-natural-homemaker model of society.

Upsetting to critics of EP theories is the suggestion, popularized in the press, that what is biological is unchangeable. "One of my objections to evolutionary psychology," explains Mary Gergen, Ph.D., professor of psychology and women's studies at Pennsylvania State University-Delaware County and a hard-core believer that gender is primarily a social construct, "is that it tends to stabilize and justify existing patterns of social relationships. They say they are presenting 'just the facts ma'am,' but it justifies the status quo."

Certainly, the idea put forth by evolutionary psychologists about the origins of gender differences is a conservative take on the matter. Conservative in the old sense of the word: inclined to preserve existing conditions and to resist change. Conservative, too, in the political sense of the word, as these debates quickly descend from the ivory tower and onto the ground, where policy is determined and intimate relationships are worked out. It's a position that offers an in-your-face challenge to feminists and other women activists who have tried to move American society in the direction of the egalitarian ideal, bolstered by the philosophical perspective that human psychology is eminently mutable.

Researchers, a good number of them self-identified feminists, who had been happily testing sex differences, suddenly felt called to action not only to "put out fires," as one said, but to come up with alternative solutions to the question of origins.

"I started to address [the origins question] because it was being addressed very directly by evolutionary psychologists," explains Mice Eagly, Ph.D., a professor of psychology at Northwestern University who had been working on questions of sex differences for 20 years. To her, their explorations of evolution were becoming "imperial," suggesting that all sex differences had biological basis.

All of these researchers agree on some theoretical basics: the nature-versus-nurture debate is moot; the differences between men and women are the result of humanity moving through the environment. Even EPs, though they believe change is slow, agree that "evolution," as Geary explains, "does not lead to a fixed point. Women harassing their men [over childcare] will lead to more investment in their children. There's some kind of wiggle-room."

"This is more than wiggle room," Eagly insists, and it's there that the battles begin. "Yes, there is a lot of sexual selection for the biological side of things," agrees Janice Juraskca, Ph.D., professor of psychology at the University of Illinois, "but one of the things that got selected that these guys [EPs] often forget is a flexible human brain." It's the flexibility question that's key, and it's on that question--a question that has major political and personal implications--that all battle-lines between the girls and the guys are drawn.

Eagly and a former student, Wendy Wood, Ph.D., now a professor at the Texas A&M University, have been working together to offer an alternative, what they call their "bio-social" model. Their work spans the fields of psychology, investigating hormones, cultural bias and other cross-cultural and cross-species evidence to determine what they consider a more complex understanding of gender differences.

Like the EPs, Eagly and Wood reject social constructionist notions that all gender differences are created by culture. But to the question of where they come from, they answer differently: not our genes but our roles in society. This narrative focuses on how societies respond to the basic biological differences--men's strength and women's reproductive capabilities--and how they encourage men and women to follow certain patterns. If you're spending a lot of time nursing your kid, explains Wood, "then you don't have the opportunity to devote large amounts of time to developing specialized skills and engaging tasks outside of the home." And, adds Eagly, "if women are charged with caring for infants, what happens is that women are more nurturing. Societies have to make the adult system work [so] socialization of girls is arranged to give them experience in nurturing."

According to this interpretation, as the environment changes, so will the range and texture of gender differences. At a time in Western countries when female reproduction is extremely low, nursing is totally optional, childcare alternatives are many, and mechanization lessens the importance of male size and strength, women are no longer restricted as much by their smaller size and by child-bearing. That means, argue Eagly and Wood, that role structures for men and women will change and, not surprisingly, the way we socialize people in these new roles will change too. (Indeed, says Wood, "sex differences seem to be reduced in societies where men and women have similar status," she says. If you're looking to live in more gender-neutral environment, try Scandinavia.)

Certainly these are more optimistic theories for women who have themselves moved into the "male" world of work outside the home. "I think," continues Eagly, that "we would expect the shift only toward women taking on masculine qualities, because that's where the social change has been in terms of roles," she explains. "Women have moved into a lot of male-dominated [areas]. You don't see the reciprocal shifts psychologically--men becoming kinder and more nurturing," she says, because the social changes haven't produced more contact between men and babies. What's critical for more equality, she says--equality being one of her goals--is a "less sharp division of labor."

In a footnote in his book Civilization and Its Discontents, Sigmund Freud offers a bizarre account of the origin of differences between the sexes. When left alone with a campfire, he explains, primitive man could not help but urinate on it. It was in his nature, a working out of his homosexual struggle with a competitive penis-symbol, the flame. It was part of being anatomically able and competitively-prone. See a fire, piss it out. That's how women--clearly less able in this sport--become the tenders of the hearth.

Certainly no one would debate that--were we able to put Freud on his own couch--this theory would tell us more about its author than about the origins of gender differences. We might interpret the theories of some liberal psychologists in a similar vein. In the heady revolutionary 1960s and '70s, they believed you could banish gender differences with a little re-education. "We thought," explains Diane Halpern, Ph.D., a professor of psychology at California State-San Bernadino, who began her research in the late 1970s, "that there weren't going to be many [differences], that they weren't going to be significant, and those that there were could be attributed to bias." (She has since revised her thinking.)

In the development of current theories, there's a lot more research going on. Eagly and Wood are working on a series of papers to prove their "social roles" theory. In his book, Male, Female (APA, 1998), Geary used some 1,200 references. "I had to do overkill in order to prove the point," he reflects, "because there's so much resistance to the idea that there are real biological differences."

But even with all this research, dramatic differences in interpretation come into a relief, along with a clear gender divide over the question of whether men and women must--biologically--adhere to certain behaviors. That story of philandering fathers developed by the EPs, for instance, could be just a story.

Indeed, says Lynn Miller, Ph.D., professor of communication and psychology at the University of Southern California, it's possible to tell an entirely different evolutionary tale. Forget the abandoning fathers. To her, "we were adapted for the important role of fathers as well as mothers." Miller argues that because human birthing is so difficult--the newborn's head is larger than the birth canal--and because human infants are so fragile, humans depend on fathers' active involvement. "We probably are the descendants of men who gave that additional care," she says. And, she adds, "When you look across cultures, where fathers are more heavily involved with offspring, their children are more likely to delay sexually activity, less likely to be violent, and more likely to be in a monogamous and more enduring relationship."

Raises eyebrows, doesn't it? The guys are telling us that men will naturally wander, and the gals, whether they follow evolutionary, social-role or social-constructionist theory, are telling us that's not so. They've all got something to back up their narrative, but there's one thing to remember: Each of these narratives was born creatively, at least in part, from the head of the researcher who promotes it. So before we are drawn into their battle of the sexes, perhaps we should be putting today's gender explorers on the couch as well.