THURSDAY, Feb. 19, 2004 (HealthDayNews) -- When and how women criticize each other relates to their competition for mates, contends a new Canadian study.
"One potential strategy for competition is competitor derogation -- using tactics to make a rival inferior to oneself," says study author Maryanne Fisher, from York University in Toronto.
The researchers, who compared how women rate the attractiveness of other women's faces during periods of low and high fertility, found that women in a highly fertile phase of their menstrual cycles gave much lower ratings to other women's facial attractiveness than did women in a less fertile phase.
Women in the study rated men's facial attractiveness almost identically, whether the women were in high or low fertility phases. In both phases, however, their ratings of male attractiveness were lower than their ratings of other women's attractiveness.
Previous research indicates that female attractiveness is seen as a potential means of competing for mates best able to provide adequate food and shelter and protect children.
"Devaluing the facial attractiveness of a same-sex rival would indicate this phenomena occurring," Fisher says in a prepared statement.
"And it was further hypothesized that during periods of high fertility -- when the potential for conception and competition for a 'good mate' was greatest -- women would be most critical of a rival's appearance," she says.
The study will be published in the online journal Biology Letters.
To learn more about preparing for marriage, visit the American Association for Marriage and Family Therapy.