New research published in Social Sciences suggests that altruism is a sexually selected trait that signals a man’s competence as a potential partner and parent. The study found that women judged a man as more desirable for a long-term relationship — but not for a one night stand — when he was seen giving a considerable donation to a homeless man.
There has been much interest in understanding why people help others even if the sacrifice comes at a personal cost. While one theory suggests that people help others because they expect help to be reciprocated, this does not explain why people help strangers who are in no position to return favors.
Study authors Wendy Iredale and colleagues were motivated to explore a more recent theory that suggests that altruism is an adaptive trait that has partly evolved from female mate preferences. The idea comes from evidence that men tend to up their altruistic behavior in the presence of women, possibly because women find it attractive. A follow-up question, then, is whether altruism is adaptive because it signals good genes that will be passed on to offspring, or because it signals good parenting qualities that will promote the survival of offspring.
Iredale and her team set out to address this question by exploring women’s preferences for men who display altruistic behavior.
The researchers recruited a sample of 285 women to partake in a study. The women were shown one of three different versions of a video clip featuring the same two actors: a young man and a homeless person. In the video clips, the young man is seen using a cash machine to withdraw £30 before encountering a homeless person. Next, depending on the version of the video, the man is seen giving either £30, £1, or nothing to the homeless man.
Importantly, before watching the videos, the women were told that the man at the cash machine was either “rich” or “poor”. After viewing the videos, the women rated the man across several characteristics.
The researchers found that, regardless of whether the women had been told the man was rich or poor, the man was judged as most attractive when he gave £30, compared to £1 or nothing. Interestingly, there were no significant differences between the attractiveness ratings when the man gave £1 versus nothing — suggesting that only a sizeable donation was attractive to the women. The £1 donation, the researchers say, may have come across as inadequate after the women had watched the man withdraw £30.
The findings revealed that this altruistic behavior was seen as a favorable trait in long-term partners, but not short-term partners — suggesting that the behavior is not an indicator of genetic fitness. When the women were asked how likely they would be to consider a long-term relationship with the man in the video, those who had watched him give money to the homeless were more likely to respond positively. However, when asked how likely they would be to consider him for a one night stand, the women’s responses were not affected by his charitable behavior.
The women also rated the man as having better parenting qualities the more money he gave, suggesting that altruism signals favorable qualities to do with child-rearing and family providing. “By showing a willingness to share resources with others, men can signal good parental “dad” qualities,” the authors say, such as being able and willing to share resources with future children. “Whilst offspring’s survival can be aided by parents passing on their genetic code (good gene quality)—because, compared to other mammals, human babies are more vulnerable and require a longer period of parental care—there are also fitness benefits for mating with men who signal the potential for good future parental care (Portmann 1990; Trivers 1972).”
Iredale and her colleagues contend that altruistic behavior, despite involving a personal cost, is an adaptive trait that comes with the indirect benefit of boosting one’s attractiveness to potential partners. Among other avenues of research, the authors suggest exploring how different types of altruistic behaviors are evaluated by women, such as non-financial altruism or volunteering.
The study, “Giving Guys Get the Girls: Men Appear More Desirable to the Opposite Sex When Displaying Costly Donations to the Homeless”, was authored by Wendy Iredale, Keli Jenner, Mark Van Vugt, and Tammy Dempster.