From Time:

Scientists at the Karolinska Institute studied brain scans of 90 gay and straight men and women, and found that the size of the two symmetrical halves of the brains of gay men more closely resembled those of straight women than they did straight men. In heterosexual women, the two halves of the brain are more or less the same size. In heterosexual men, the right hemisphere is slightly larger. Scans of the brains of gay men in the study, however, showed that their hemispheres were relatively symmetrical, like those of straight women, while the brains of homosexual women were asymmetrical like those of straight men. The number of nerves connecting the two sides of the brains of gay men were also more like the number in heterosexual women than in straight men.

The doctor in the study writes that "For the first time, in this study it looks like there are regions of the brain not directly involved in sexuality that seem to be feminized in gay males." I used to cringe at this kind of research -- because I'm really uninterested in "proving" the biological nature of homosexual desire. I think desire is much too complicated to be linked to one gene or hormone exposure. That is to say, for many people, these things shift over time and aren't as set in stone (although, fair to say, that for many of us, desire does stay somewhat static over the life course -- at least in terms of gender).

But I'm a bit more open to this kind of data now -- as long as it is carefully applied and analyzed. It's no surprise that there might be biological differences among some gay men and other folks. While as a sociologist I believe that much of our differences come from culture, they surely may also have roots in our biology. One of these differences that sticks out in my mind is gay men's tendency -- as a group -- towards non-violence. We just aren't very violent people. Lesbians are more violent, and so are straight men. This is the kind of stuff that Dave Nimmons talks about in his book, The Soul Beneath the Skin. Is this related to our brains? In the end, we'll probably never know. But it sure does getcha thinking!