"With some exceptions, the vast majority of couples select partners who are similar to themselves in both status and in attractiveness," says University of Notre Dame Sociologist Elizabeth McClintock, who studies the impacts of physical attractiveness on mate selection (in humans, to be clear).

To start your relationship out happily, it may be important to pick someone at your same attractiveness level! The latest research reveals three truths, ranging from not surprising to more interesting: McClintock sums it up by saying that just as good looks may be exchanged for status and money, attractiveness may be traded for control over commitment and the progression of sexual activity.

• For women, the number of sexual partners decreases with increasing physical attractiveness, whereas for men, the number of sexual partners increases with increasing physical attractiveness.
• Very physically attractive women are more likely to form exclusive relationships than to form purely sexual relationships; they are also less likely to have sexual intercourse within the first week of meeting a partner.
• For women, the number of reported sexual partners is tied to weight: Thinner women report fewer partners. As thinness is an indication of attractiveness for many women, this finding is consistent with the reporting that more attractive women have fewer sexual partners.

McClintock notes: "the woman's beauty and the man's status (education, income) are positively correlated, that is, they tend to increase and decrease together." But, she notes that oft-ignored factors include, "People with higher status are, on average, rated more physically attractive—perhaps because they are less likely to be overweight and more likely to afford braces and nice clothes and trips to the dermatologist, etc."

But also: "The strongest force by far in partner selection is similarity—in education, race, religion, and physical attractiveness," says McClintock. This would suggest: "With some exceptions, the vast majority of couples select partners who are similar to themselves in both status and in attractiveness."

Just in time for Valentine's Day—find a mate who is equal to you!

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