For men, online generosity is a competition

Researchers say that they suspect this tendency is a subconscious part of human psychology that exists because it is (or was) evolutionarily beneficial to us.

"People are really generous and are right, a lot of the time, to say that their motives for giving to charity are altruistic, not self-serving," says Nichola Raihani of UCL (University College London). "This does not, however, preclude these motives from having evolved to benefit the donor in some way."

While the findings make perfect sense from an evolutionary point of view, the researchers say they were still quite surprised at how clear it was from their real-world data that people--and particularly men--engage in "competitive helping." Earlier studies had primarily involved games played in the lab.

In the new study, Raihani and Sarah Smith of the University of Bristol relied on a large, UK-based, online fundraising platform to test a key prediction of the competitive helping hypothesis: that males respond competitively to the generosity bids of other males in the presence of attractive females. On the platform, people host fundraising pages including their personal information--name, photo, charity, and the event they are being sponsored for--and collect donations, mostly from people they know. Donations are made and posted sequentially, along with the name of the donor (unless they've opted for anonymity).

"This creates a potential tournament in which donors may compete by responding to how much others have given," Smith says.

Smith's earlier work showed that existing donations on a page act as a kind of "anchor" for current donors. In other words, seeing a small or a large donation influenced what subsequent donors were willing to contribute. Raihani and Smith wanted to know whether the behavior of donors would also be influenced by the gender and attractiveness of the fundraiser, along with the gender of the previous donor. And, indeed, it most certainly was.

That's not to say that anyone is really making these decisions about giving in a conscious or purposeful way, the researchers say.

"We don't think that males are seeing large donations from other males to attractive female fundraisers, and then thinking 'Yeah, I'll give more than him because she will find me more attractive then.' In fact, I think that is quite unlikely," Raihani says.

"I think it is more likely that humans have an evolved psychology that motivates us to behave in ways that would have been, on average, adaptive in our evolutionary past--and may still be nowadays also."

The findings do suggest ways to improve the success of fundraising campaigns. First of all, fundraisers should smile. The attractiveness ratings of female fundraisers had a lot to do with their facial expression. And it may pay off to seed a campaign with larger donations early.

"Large donations can elicit other large donations, so fundraisers might raise more if they get their most generous friends or family to donate early in the appeal," Raihani says.