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Society Does Not Make Gender

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Ruth Padawer's New York Times magazine exploration of boys whose behavior doesn't fit neatly into typical male molds has tapped into an argument that appears to have gained currency recently as a skirmish in our ongoing cultural warfare. Unfortunately, neither side seems to have heard of something called the Organizational Hypothesis.

According to the hypothesis, during fetal development male and female hormones not only help direct the formation of our bodies, they also shape the wiring of our brains. Society -- toy makers, churches, parents, fashion magazines -- does not make gender.

Science had clues to this as early as 1916. But it was in 1959 that Charles H. Phoenix and colleagues conducted the keystone experiment. They gave testosterone to pregnant guinea pigs and found that daughters were often born with what human doctors would call "ambiguous genitalia." Their bodies had been masculinized.

But Phoenix's animals didn't just look more like males, they acted more male-like, too. They mounted prospective sex partners about as often as males did. The prenatal male hormone had organized their brains in a male-typical pattern.

This gender-specific brain organization is vital. After all, male and female brains have to regulate different processes, like ovulation and menstruation in women, and sperm production in men.

Some argue, tritely, that "animals aren't people." But the core systems that drive reproductive and social behaviors in humans are similar to those in animals, and research over the past fifty years has supported the basics of the Organizational Hypothesis.

Take the case of some children who lived around the small Dominican Republic town of Las Salinas. As a team from what was then Cornell University Medical College (today's Weill Cornell) discovered in the 1970s, they were born looking very much the way little girls usually look. Naturally, they were raised as girls.

But local people called them machihembra, "first woman, then man" because, at age 12 or so, they appeared to develop penises and testicles. In fact, they'd always had them but a genetic mutation caused an enzyme deficiency. That muted hormonal signals for genital growth until the overpowering rush of testosterone at puberty sent the testicles descending and the penises growing.

Despite years of socialization, and formerly looking like girls, they readily accepted their identity, they often married, and they fathered children because their brains had not been affected by the enzyme deficiency. They were always typically male.

Such organization, not advertising, is why boys, as a group, are more likely to shoot a doll full of BBs, while girls, as a group, are more likely to dress dolls and "nurture" them.

Many social conservatives tend to like this part of the story since they believe there are only two natural and proper genders, and behavior within those genders must be highly circumscribed. Meanwhile, some (not all) feminists reject it, arguing there are no important brain differences between males and females.

This has made for some odd, if unwitting, bedfellows, especially when the forces described by the hypothesis, which allow for a wide range of gender possibility, make atypical people.

For example, cells in those born with a condition called complete androgen insensitivity cannot "hear" the signals male hormones are sending. So, while they are chromosomally male, their brains are female. They are women. Yet Germaine Greer has argued that since they have a male set of chromosomes, they're men posing as women.

In 2011, when transgender people petitioned New York City to let them alter their birth certificates, Peter Sprigg, an official with the Family Research Council, called it "fraud," arguing that "you have the objective reality of their genital makeup and their chromosomal makeup."

Society can look at genitals, or chromosomes, and try to force people to conform to expectations in opposition to their wiring. It can also try to ignore real differences between typical boys and girls. Both are recipes for misery because, in the end, our brains will out.

Acknowledging difference and variety says nothing about a person's competence, or intellect, or morality. So rather than seeing threat, we should embrace all shades of gender, whether snips and snails, sugar and spice, or somewhere in between.

Emory University's Director of the Center for Translational Social Neuroscience Larry J. Young, Ph.D., and award-wining science journalist Brian Alexander, authors of the forthcoming book 'The Chemistry Between Us,' to be published September 13 by Current.