A new study has found that men and women’s actual day-to-day experience with opposite-sex friends differs from what comes to mind when they think of an opposite-sex friend.

The study in Evolutionary Psychological Science found that men were more likely to think of an opposite-sex friend as “a member of the opposite sex to whom I am attracted and would pursue given the opportunity” while women were more likely to think of them as simply “a friend of the opposite sex.”

But the researchers found a different result when they approached students at a university who were accompanied by an opposite-sex friend — and then separated the duo to examine their perceptions of one another. They discovered that male and female friends’ attraction to one another varied widely.

PsyPost interviewed the study’s corresponding author, April Bleske-Rechek of the University of Wisconsin at Eau Claire. Read her responses below:

Why were you interested in this topic?

Bleske-Rechek: I have been interested in both same-sex and opposite-sex friendships, and close relationships of any kind, actually, since well before graduate school. In graduate school, my advisor (David Buss) and I began studying friendship with an evolutionary lens, and hence we began to consider the ways in which our evolved mating strategies might impinge on our experiences with opposite-sex friends.

We did that because, defined as a voluntary, non-reproductive alliance between non-genetically related members of the opposite sex, these relationships — at least among young adults — seem to be a bit of an evolutionary novelty.

What should the average person take away from your study?

The current set of studies, taken as an aggregate, supports my general hypothesis that young adult heterosexual men and women, on average, have somewhat different mental definitions (or characterizations) of “opposite-sex friend.” When men and women think of an opposite-sex friend, men are more likely than women to think of a friend to whom they are attracted.

Are there any major caveats? What questions still need to be addressed?

So many questions remain. First, the hypothesis above needs to be tested in multiple ways, so my conclusion is very tentative. At the least, I think we can conclude that the opposite-sex “friend” who comes to a given person’s mind when someone asks them about friends might not be the same “opposite-sex friend” they hang out with at any given time of the day. This issue does not happen with romantic partners! If I ask people to tell me about a romantic partner of theirs, I can be reasonably confident they are going to tell me about their current romantic partner because most people have one partner at a time (multiple sex partners perhaps but usually serial monogamy with romantic partners.)

I am trying to figure out whether male and female friendship partners send signals that match their stated intentions or desires (because they may not be aware of their desires). Students and I are currently beginning a study of young adult male-female dyads in which outside judges observe each dyad for 90 seconds and attempt to determine whether they are romantically involved or “just friends” (or somewhere in between). After each observation, dyad members are separated and questioned about their relationship and their attraction to one another. The point is to try to figure out whether opposite-sex friends tend to send nonverbal cues of being romantically involved (even when they are not), and whether men or women tend to send off those cues more often.

The study, “Sex Differences in Young Adults’ Attraction to Opposite-Sex Friends: Natural Sampling versus Mental Concepts,” was co-authored by Whitney E. Joseph, Heather Williquette and Bryan Donovan.