in scientific tests, women become aroused when they watch a film of two copulating bonobos (men don’t, by the way), and that they strongly deny this arousal when asked. The explanation, proffered tentatively by Bergner, is that female sexuality is as raw and bestial as male sexuality. But, unlike men, our animal urges are stoutly denied, by society and by ourselves, so that when they surface, it is not as a manageable stream, but as a rushing torrent that will sweep up everything it passes, even a pair of shagging primates.
As they enrolled in the study, Chivers’ subjects identified themselves as straight or lesbian. They were shown images of sex between men and women, women and women, men and men, and a pair of bonobos (a species of ape). The subjects, straight and lesbian, were turned on right away by all of it, including the copulating apes. While they watched, they also held a keypad on which they rated their own feelings of arousal. So Chivers had physiological and self-reported scores. They hardly matched at all. Chivers’ objective numbers, tracking what’s technically called vaginal pulse amplitude, soared no matter who was on screen and regardless of what they were doing, to each other, to themselves. The keypad contradicted the plethysmograph entirely. The self-reports announced indifference to the bonobos. But that was only for starters. When the films were of women touching themselves or enmeshed with each other, the straight subjects said they were a lot less excited than their genitals declared. During the segments of gay male sex, the ratings of heterosexual women were even more muted.
Chivers put heterosexual and homosexual males through the same procedure. Strapped to their type of plethysmograph, they responded in predictable patterns she labelled “category specific”. The straight men did swell slightly as they watched men masturbating and slightly more as they stared at men together, but this was dwarfed by their physiological arousal when the films featured women alone, women with men and, above all, women with women. Category specific applied still more to the gay males. Their readings jumped when men masturbated, rocketed when men had sex with men, and climbed, though less steeply, when the clips showed men with women; the plethysmograph rested close to dead when women owned the screen.
As for the bonobos, the genitals of both gay and straight men reacted to them the same way they did to the landscapes, to the pannings of mountains and plateaus. And with the men, the objective and subjective were in sync. Bodies and minds told the same story.
How to explain the conflict between what the women claimed and what their genitals said? Were the women either consciously diminishing or unconsciously blocking out the fact that a vast scope of things stoked them instantly toward lust?