Previously, other studies have found that women prefer "thick" faces of the opposite sex during ovulation, or that they prefer "more masculine" faces of the opposite sex when they are looking for a short-term relationship, and "softer" faces when they choose a long-term partner. ” faces are more popular.

This explanation consistent with the evolutionary perspective is clearly consistent with Gunstadt's new research results. Manuel Nyqvist, an expert on gender relations at Stockholm University in Sweden, said: "In social situations and in the field of evolutionary psychology, there is a scientific consensus that women may get better genes from men other than their partners. But the evidence to support this idea is still scant. ”

Genetic selection vs. emotional harm

Gonstadt’s research suggests that women may indeed benefit from sex with men other than their partners. Genetic advantages are obtained in relationships, but exposure of infidelity may cause serious harm. In order to enjoy the genetic advantages to the greatest extent and avoid emotional harm, Gunstadt speculated that women have stronger feelings towards other members of the opposite sex during the ovulation period (the fertile period). "Sex" interest.

Gonstadt and his team conducted a questionnaire survey of 51 women (during their ovulatory and non-ovulatory periods), 24 women said they had a single opposite-sex partner, and 7 women They said they had no fixed partners but had important partners of the opposite sex.

The research team found that women's attraction and attraction to other men increased before ovulation, while interest in their primary partners remained the same.

Women with fixed or main opposite-sex partners also reported that during ovulation, their opposite-sex partners paid at least 30% more attention to them, accompanied by "monopolistic" behavior: such as calling them from time to time to ask about their sex. whereabouts.

Gonstadt said: "The partners of women who were more interested in other men also seemed to be more alert."

However, none of the women surveyed reported being interested in other men. Partners were unfaithful, which Nyquist believed undermined their proposed evolutionary explanation.

Gonstadt admits that he doesn't know where men get their cues and react, "Perhaps there are subtle clues hidden in their partners' scent or visual signals, or a response to action." A direct reaction to seeing your partner’s interest in other men.”