Looks may matter more than anything else to men and women when it comes to finding a partner for short-term sexual relationships, according to a study in the March Journal of Personality and Social Psychology (Vol. 90, No. 3). The study, by Norman Li, PhD, of the University of Texas at Austin, and Douglas Kenrick, PhD, of Arizona State University, finds that although men and women differ in their willingness to participate in one-night stands, when they choose to, both genders prioritize looks in their partners.

The findings contrast with Li and Kenrick's previous finding that in the case of long-term mates, both sexes desire well-rounded mates, but women tend to prize status and men first seek out physically attractive mates.

Li and Kenrick ran five studies to explore short-term mate selection. In the first two, 394 heterosexual undergraduates designed their ideal short-term mate using "mate budgets" in which participants had varying amounts of "mate dollars" to assign to different characteristics, effectively forcing participants to rank the degree to which they seek characteristics such as "kindness," "physical attractiveness" and "social status" in a short-term mate. In both studies, men and women allocated more than double the portion of their budget for physical attractiveness than for any other characteristic or trait. However, when the students were asked if they would have a one-night stand or short-term relationship with the mate they created, men were much more willing to respond affirmatively.

In a follow-up study, the researchers asked participants to recall the last time they considered having casual sex and to rate the extent to which they were motivated by factors such as physical attraction, a desire for a long-term relationship with the partner or an effort to enhance their social reputation. Of the participants who had considered having casual sex, the highest-rated reason was "I was physically attracted to the person, and I thought it would feel good."

Although men and women are similarly motivated in choosing short-term sexual relationship partners, they differ in their willingness to actually engage in such relationships, the findings indicate. As a result, "Higher-quality men often hook up with lesser-quality, though reasonably attractive women," Li says.

The five studies, Li suggests, add to a growing body of research on gender similarities and differences in mate choices, as well as what people seek in mates for different levels of involvement, whether they are willing to consider such involvements and why those variations may exist.

In future studies, Li and his colleagues aim to investigate how people's standards for mates change over time.