During the experiments, once subjects had been named either leaders or followers, they were frequently reminded of the survey results, making them aware of what their peers expected of them. When leaders’ power over a situation was relatively low, roughly half of them stayed true to the social norms they helped develop; this dropped to 19 percent when they were given more power. Also, the greediest behavior was linked to high baseline levels of testosterone.

“This is an interesting finding,” says Cornell professor Vanessa Bohns, “but I would caution against interpreting it too broadly.” According to Bohns, it’s not so much that power and testosterone cause people to behave corruptly—it’s that they make people less inhibited. “In another context, high-power people may be more likely to jump in and help in an emergency because they are similarly more likely to violate the social norm of standing around,” she says.