A new study composed of three experiments by the University of Toronto and Tufts University shows that male sexual orientation can be accurately identified by heterosexual women close to the peak of ovulation. Results from the first experiment showed that women closer to the peak of ovulation were more accurate in judging male sexual orientation based on grey-scale photos of gay and straight men. In the second experiment, the women tended to identify photo targets of straight and lesbian women mostly as straight, suggesting that fertility during ovulation is only useful when determining male sexual orientation. The photos used in these two experiments were controlled for emotional expression and attractiveness. The third experiment went further by manipulating the reproductive relevance of the male subjects. Women induced to have romantic or mating-related thoughts were drastically more precise in judging male sexual orientation than women who were not.
Source: Science Daily
