Research has found that though lesbians are much more attracted to the female form , most women who say they are straight are in fact aroused by videos of both naked men and naked women. The study, led by Dr Gerulf Rieger from the Department of Psychology at the University of Essex, involved women whose responses to being shown videos of naked men and women were analysed. This was in contrast to lesbians, who showed much stronger sexual responses to women than to men. The researchers said lesbians were the most like men in their responses because it is usually men who show distinct sexual responses to their favourite sex. Dr Rieger said: "Even though the majority of women identify as straight, our research clearly demonstrates that when it comes to what turns them on, they are either bisexual or gay, but never straight.

The dilemma I have known I was gay since I was a boy, but recently I have started having sexual feelings for women that I've spent a lot of time with at university. I went to a single-sex school and have never really had any female friends. I wonder if this might have contributed to my belief that I was gay.

Meredith Chivers is a creator of bonobo pornography. The bonobo film was part of a series of related experiments she has carried out over the past several years. She showed the short movie to men and women, straight and gay. To the same subjects, she also showed clips of heterosexual sex, male and female homosexual sex, a man masturbating, a woman masturbating, a chiseled man walking naked on a beach and a well-toned woman doing calisthenics in the nude.