Societal gender norms suggest that women should be most concerned with declarations of love, especially during the early, uncertain phase of relationships. After all, who are all those romantic comedies and chick flick movies marketed toward? But recent research demonstrates that in fact, it’s the men who are more likely to say “I love you” first in relationships.1 Not only that, but hearing “I love you” from a romantic partner for the first time makes men even happier than it makes women. And although this may not jive with gender stereotypes, it makes a lot of sense from an evolutionary perspective.

Because of the differences in our biological make-up, women take nine months each time they wish to reproduce, whereas men can take only a few minutes. According to parental investment theory, this difference makes women a lot choosier when it comes to mates: not only do they want to ensure that they pick a partner with good genes, but they also want to end up with a partner who’s likely to stick around to help with child rearing.2

From this perspective, it makes sense that men would have evolved a willingness to profess their love early on, whereas women would have reason to be more cautious or sceptical. Indeed, Ackerman and colleagues demonstrated that whereas men value love professions most before the couple has had sex for the first time, women are most impressed with love professions if they are made after the couple has had sex. And this may not be just a gender difference: the researchers also found that people (of both genders) who desire more casual relationships prefer to say or hear “I love you” prior to having sex, whereas people who want long-term relationships place greater value on such statements after sex. It seems that early on, professions of love may be a sign of impending sex (“This person really likes me… I might get lucky!”). However, for someone who is hoping to keep it casual, professions of love made after sex can create feelings of obligation and guilt. In contrast, for those who are looking for the “real deal”, emotional sharing after the sex may seem more genuine: it gives them some assurance that their partners are not just trying to get into their pants.

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1Ackerman, J., Griskevicius, V., & Li, N. (2011). Let’s get serious: Communicating commitment in romantic relationships. Journal of Personality and Social Psychology, 100, 1079-1094. DOI: 10.1037/a0022412

2Buss, D. M., & Barnes, M. (1986). Preferences in human mate selection. Journal of Personality and Social Psychology, 50, 559-570.

Samantha Joel – Science of Relationships articles

Samantha’s research examines how people make decisions about their romantic relationships. For example, what sort of factors do people take into consideration when they try to decide whether to pursue a potential date, invest in a new relationship, or break up with a romantic partner?