The saying, "survival of the fittest" doesn't only refer to a man's physical ability to overcome physical threats. It also refers to mating. Women chose men who were strong and able to protect them against threats, build shelters and provide food. Therefore, the "fittest" were more likely to have a mate and children to carry on the family line. As mating evolved and strength was no longer a prerequisite to staying safe and well cared for, women were free to look for other traits in their mates and could take compatibility into account. Despite the evolutionary changes, studies have shown that women are more attracted to the "manly" man when they are ovulating.
Studies have shown that women are attracted to different types of men depending on their ovulatory cycle. When women are near ovulation, they are more attracted to "manly" men, those with strong physical features, are highly competitive and show traits of dominance. If their current partner doesn't fit into this category, they are more likely to be attracted to other men. If their partner is considered attractive, they are less likely to be attracted to someone outside their marriage. Researchers believe that women are attracted to "good genetics." This does not mean, however, that women acted on this attraction and sought out extra-marital affairs.
Being on birth control changes a woman's cycle. Because it simulates pregnancy she no longer ovulates each month. A study completed in 2009, indicated that the lack of ovulation while a woman is on the pill may result in her choosing a mate she would not choose had she been ovulating. The study suggested that this choice impacts her children, their health and their perceived attractiveness. [Alvergne, 2007,Trends in Ecology & Evolution]
While the study proves interesting, other doctors don't believe there is much definitive data to draw conclusions like this. Dr. William Hurd, a reproductive endrocrinologist at University Hospitals Case Medical Clinic in Cleveland, in an article that appeared on HealthDay, indicates that this study doesn't take into account social and emotional influences in choosing a mate. He explains that while a woman may change who they are attracted to during different stages of their reproductive cycle, it does not necessarily mean they would change who they would choose as a long-term partner, which is based on much more than physical attraction. According to Dr. Hurd, "I don't think there are many women who change who they would mate with at different times of the month. It might change desires or perceptions but, gee whiz, that's a long stretch to changing who you would date, or even who you would go to dinner with."
Alexandra Alvergne, the lead researcher in the study, believes further research is needed to answer questions as to whether being on the pill changes the way married couples relate to one another and whether it effects their ability to have children. But Dr. Hurd believes that compatibility plays a larger role in dating and that new socially accepted ways of meeting people, such as online dating services, take this into account and will change the way we meet, date and choose our partners.
Birth Control Pills Might Alter Mate Selection: Study, 2009, Amanda Gardner, HealthDay, HealthScout.com
Near Ovulation, Your Cheatin' Heart Will Tell on You, Find UCLA, University of New Mexico Researchers, 2006, Jan 4, Meg Sullivan, UCLA Newsroom
"Women's sexual interests across the ovulatory cycle depend on primary partner developmental instability," 2005, Aug, Steven W Gangestad, Randy Thornhill, and Christine E Garver-Apgar, Proceedings of the Royal Society of Biological Sciences