Several bodies of research have suggested that men with wider faces tend to be more aggressive, less trustworthy, and more prone to deceiving others. But whether it’s because of evolutionary reasons or because wider faces have been associated with higher levels of testosterone, a new study says that the blame can’t be placed squarely on those with wide faces. Those who interact with wide-faced men tend to treat them more selfishly too.

The findings “clearly show that this behavior is also socially driven, not just biologically driven,” Michael Haselhuhn, an assistant professor of management at the University of California, Riverside, School of Business Administration, said in a statement.

Haselhuhn built upon two other studies that he authored with assistant professor of management at UC Riverside, Elaine Wong. In one, they found that men with wider faces tended to be CEOs of more financially successful companies, compared to narrow-faced men, who were more likely to lead financially unsuccessful companies. The second study found that with two experiments, men with wider faces were more likely to deceive in negotiations and cheat in order to achieve financial gain.

Their new study involved four experiments. The first one involved 131 men who were given money to participate in the survey. They didn’t know that they’d be subjected to a test in which they would be asked to give some of their money away. Along with answering surveys, the researchers found that the participants with wider faces tended to worry more about their financial outcome than to give their money away.

The second experiment involved the same test, however, with different participants. They were given photos of the first experiment’s participants and told their choices would affect both them and their counterpart from the first experiment. Those whose counterpart had a wide face tended to ensure their financial gain more often.

The third experiment built on the last one, but with 255 new participants, and photographs that were edited to look like some faces were wider. Once again, participants were asked to allocate their money based on how they felt their counterparts would react, and how it would affect both of their outcomes. But this time, they were also told to verbally express how they felt their counterpart would act. Participants whose counterparts were wide-faced not only kept more money for themselves, but predicted that the person in the photos would as well.

The fourth experiment, once again, built on the rest. This time however, participants were told what their counterpart in the photos had decided they would do with the money. They did this to see if it would elicit selfish behavior, and surely, it did. “These results illustrate that simply treating people as if they are men with relatively [wide faces] yields more selfish behavior,” the researchers wrote.

“The current research illustrates the power of social perceptions in shaping individuals’ behavior, however, it is important to revisit the possibility that biological and social factors may work in concert to strengthen links between [wide faces] and behavior,” they wrote.

Source: Haselhuhn M, Wong E, Ormiston M. Self-Fulfilling Prophecies as a Link between Men’s Facial Width-to-Height Ratio and Behavior. PLOS One. 2013.