According to Howard University researchers, aggressive men tend to turn down free money if they are being offered a very small share of the stakes involved.
During a study, 26 male students were presented with ultimatums. Each of them was offered five dollars out of a possible 40 dollars by another person. A student could either take the offered amount or leave the rest to the offerer, or both parties would not get anything.
Harvard economist Terence Burnham took saliva samples from the students before the experiment began, and tested it for testosterone levels later on.
It was found that while 20 men accepted the offer of five dollars, the rest with higher-testosterone levels rejected it.
"It's strange but it's true—people at times walk away from free money. If you knew the testosterone levels of these people, you didn't need to know much more to predict behaviour. Not what culture they were from, not their political beliefs," Live Science quoted Burnham as saying.
He further said that people even tend to reject relatively large sums of money, such as two weeks' wages, if such offers are roughly one-fifth or less of the stakes involved.
Burnham explains that testosterone is linked with aggression, and people with high levels of it may become more aggressive upon receiving low offers, believing that they are being insulted.
"In a real negotiation, people have to understand that there's often more than money at stake. There are other parts of the psyche to deal with," Burnham said.
"No savvy coach who wants players to work hard will tell them they can make more money—they challenge them on some other level. Money isn't everything—if you thought that way, you'd likely be a bitter, unhappy and unsuccessful person," he added.
The researcher is of the opinion that the new findings may lead to the revision of economic models "that are the language of public policy". They may apply to areas "such as Social Security and environmental policy," he says.