What do humans really want in a long-term partner? If people were given a limited menu of characteristics from which to choose, what would be the non-negotiables? And how much of what we value in a partner is influenced by culture and how much is innate? In a nifty new report out of the University of Swansea in the U.K., researchers got 2,700 college students from five countries to progressively narrow down which characteristics were most important to them in a lifetime mate, and the one that emerged from all cultures was kindness.

The study, which was published in the Journal of Personality on Sept. 8, compared the dating preferences of students from two countries traditionally considered as “Eastern” (Singapore and Malaysia) and three counties considered as “Western” (Australia, Norway and the U.K.).

It offered up eight attributes on which participants could spend “mate dollars”: Physical attractiveness, good financial prospects, kindness, humor, chastity, religiosity, the desire for children, and creativity. Each dollar represented an increase of 10% in one trait. To make their partner funnier than 40% of the population, for example, participants had to spend $40. At first they spent big on everything, but as their budget grew smaller in each round of the study, they had to really figure out what they wanted. After kindness, men almost universally favored physical attractiveness and women chose good financial prospects.

We asked the researcher Andrew G. Thomas, a senior lecturer in Psychology at Swansea, to explain his research.

Your study looks at the differences in mating preferences between countries that are traditionally considered “Western” and countries that are traditionally considered “Eastern.” Why were you interested in this?

Within social sciences, there’s this view that attitudes and desires are primarily the product of learning or culture. As an evolutionary psychologist, I believe that some behaviors emerge consistently across cultures – they are human “universals.” Looking at very different culture groups allows us to test this idea. If we find that men and women act in a similar way across the globe, then this adds weight to the idea that some behaviors develop in spite of culture rather than because of it.

The results suggest that across the board, men show a preference for youth and beauty, while women show a preference for ability to provide. Why is that?

This is a finding that crops up time and time again within evolutionary psychology. The most convincing theory is that ancestral men and women evolved to choose partners in ways that helped them reproduce successfully, and that modern men and women continue to do this today. Because women’s fertility declines with age, ancestral men prioritized youth and beauty to ensure they picked a fertile mate. Similarly, because resources can make raising a child easier, and because the ability to provide resources varies from one man to the next, ancestral women evolved to prioritize social status to ensure they picked a mate who could invest in them and their offspring.

After those three, which you classify as necessities, the next most popular trait was humor, at least in the Western group. Did its high prioritization surprise you?

Humor ended up being a priority in the Western group, but not the Eastern one. The fact that humor was important wasn’t too surprising, as there are a few good theories that suggest that humor is important in mate selection. However, the East-West difference was surprising. Upon reflection, I think this is because some of the traits included in the task (e.g., religiosity and chastity) are more important in Eastern cultures than the Western ones. So when budgets were tight, Western participants were able to ignore these attributes and spend more dollars on humor, while Eastern ones could not.

So how different are people from Western and Eastern cultures in terms of what we want in a partner?

We found cultural differences for almost every trait. However, in most cases, these were a simply matter of degree. For example, for men and women from both cultures the most important trait, hands down, was kindness. This far outweighed traits like creativity, religiosity and humor. Sure, there were small cultural differences in the importance of kindness, but the real finding is that this was consistently a top trait.

Were there any other significant differences between men and women?

One very interesting difference was in a partner’s desire for children. We found that this wasn’t a priority in the Eastern sample at all. However, within the Western one, women gave it priority but not men. We think this may have something to do with family planning. In cultures where contraception is widespread, a partner’s desire for children may predict the likelihood of starting a family. In contrast, in cultures where contraception use is less widespread, having children may be a natural consequence of sex within a relationship, making actual desire for children less relevant.

Are there any other circumstances in which people prioritize kindness more or less in a mate?

While the precise number of dollars allocated to kindness is different across cultures and sex, these don’t change the overall finding that kindness is king. However, one thing that we know does kill kindness is a change of relationship context. In our study we asked participants to design a long-term partner. But other versions of the task have asked people to design a short-term partner. When this happens, kindness is given much less priority.

What small difference between the groups you studied intrigued you?

It always surprises me with this task that creativity takes a back seat to most other traits, and this pattern was repeated in our large cross-cultural comparison. Highly successful creative individuals, such as musicians and artists, are often highly desirable mates, but maybe what’s actually being valued here is not creativity as such but the social status that accompanies it. It makes me wonder what groupies really like about the bands they follow.

Any takeaway from all this for people who are currently dating?

First of all, I think it’s great that kindness is king and appears to be a human universal. At the same time, this type of research can give people guidance as to what attributes the other sex prioritizes when making mating decisions. If the findings of our study are correct, then men would be able to enhance their attractiveness to a greater degree by focusing on the development of their financial prospects rather than their creativity or religiosity. And this tactic may well be as successful in Norway as in Malaysia.

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