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Women are attracted to men who are altruistic and good-looking. But few men possess both these traits, and neither can simultaneously top a woman’s list of “must-haves.”

So, if you had to choose, what would be more important to you—a partner who is helpful or one who's handsome?

To find out, Daniel Farrelly, a psychologist at the University of Worcester in the UK, tested the preferences of more than 200 heterosexual women. He showed the women pairs of photographs of men. Each pair consisted of a handsome man and a less-than-attractive one, each labeled with a letter. While looking at the pair of men, researchers prompted the women to imagine a scenario in which the two men played a part.

In one scenario:

Man S and Man T are both at a picnic beside a river that has a fast current when they see a child being swept down the river, gasping for breath. A woman cries, "Help! Save my child!’’ One man in each pair acts altruistically: T hears the mother’s cries and jumps in the raging river to try to save the child. On the other hand, S sees the speed of the current and chooses not to try to help.

Here’s another scenario:

Two men are walking through a busy town and notice a homeless person sitting near a café. Man E decides to go into the café to buy a sandwich and a cup of tea to give to the homeless person. Man F pretends to use his mobile phone and walks straight past the homeless person.

Other scenarios were neutral, with no opportunity for selfless, altruistic reactions:

Man O and Man P both go clothes shopping. O decides to buy a green jacket and P buys a pair of blue jeans.

(This was the control condition: Buying a jacket instead of a pair of jeans tells us nothing about which man is more altruistic.)

After reading the scenarios, the women’s task was to rate the of each man—both for a long-term relationship, such as , and a short-term relationship, like a brief affair or one-night stand.

What Was Learned

As Farrelly expected, altruistic men received more attractive ratings than non-altruistic men, with average desirability scores ~3 compared to ~2.1. Physically attractive men, with average desirability scores of ~2.8, were more appealing than less handsome men, who scored only ~2.2. Altruism appears to be valuable at a premium: Non-altruistic men were less attractive than physically unappealing men, and altruistic men were more attractive than handsome men.

In simpler terms: A man’s physical appearance seems to be less important to a woman than his altruism.

In reality, of course, comparing altruism with physical attractiveness is like comparing apples with oranges: We don’t measure a man’s handsomeness and his on the same scale. Perhaps altruism only appears to be more valuable than good looks because of the types of scenarios Farrelly used. We could say the same for the photographs: If the difference in physical attractiveness between the paired men was insufficiently striking, we should not be surprised to find that women would place greater weight on altruism when judging men’s desirability.

More interesting were the results when Farrelly tested the effect of relationship type on women’s preferences: He found that altruists were rated more attractive for a long-term relationship than for a fling, which is not what I would have expected. Jumping into a raging torrent to rescue a drowning child strikes me as generosity bordering on heroism, and I would have thought that heroes — think firefighters— are more alluring for one-night stands than for marriage.

But what do I know? I am neither a hero nor a woman.

Farrelly also found that selfish, non-altruistic men were more appealing as short-term than long-term partners. Perhaps women see these men as stereotypical bad boys, always looking out for Number One. (Past research suggests that women prefer "cads" to "dads" when seeking a casual hookup.)

As Farrelly suggests:

"Future research needs to examine the effects found here in men’s ratings of the desirability of altruistic women as well. This is because there is a lack of such research in this area, as most studies have concentrated on only women’s ratings."

For an audio version of this story, see the 12 January 2015 episode of The Psychology of Attractiveness Podcast.

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