Drunken rowdiness at sports facilities, dangerous driving in heavy traffic, stupid and risky financial decisions, and other behaviors associated with jerks could be explained by the newly formulated "Crazy Bastard Hypothesis."

The hypothesis, outlined in the latest issue of Evolution of Human Behavior, says that part of the population -- mostly young men -- are predisposed to nonviolent risk-taking, which can improve their status.

"Specifically, the less that someone cares about their own welfare, the more dangerous they are as an opponent, because they will not be deterred by threats, and will be less likely to retreat if injured," lead author Daniel Fessler explained to Discovery News.

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"A considerable part of the psychology of young men is dedicated to competition, including potentially violent competition with other young men," added Fessler, an evolutionary anthropologist at the University of California, Los Angeles. "Advertising that one is indifferent to injury or death makes one a feared adversary and a valuable friend."

Fessler was inspired to conduct the study because he wondered why anyone would engage in non-violent risk-taking. For example, he noticed that young men in California are vastly more likely than other people to be bitten by rattlesnakes. Guys often pick up the snakes sometimes as a dare or to show off in front of others.

For the study, Fessler and his team conducted five experiments. Most looked at how both men and women perceived the size and strength of unseen risk takers. Risk-prone vignettes included things like not wearing a seat-belt, eating and texting while driving, speeding, driving through a red light, sunbathing without sunscreen, betting a day's income at a high-stakes poker game, and other risky behaviors.

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A similar study was conducted in Fiji among villagers, only this time the risky behavior vignettes including things like climbing tall coconut trees and sailing rough seas without a life vest.

In most cases, and particularly among men, knowing that a man voluntarily engages in dangerous, nonviolent activities leads others to conceptualize him as larger and stronger.

"In other words, in your 'mind's eye,' you form a mental picture that is a summary of all of the various tactical assets and tactical liabilities that you and your opponent would bring to a fight (such as weapons, the presence of allies, etc.)," Fessler said. "Conceptualizing a risk-taker as bigger and stronger thus reveals that you think of that person as more dangerous in a fight."

Texting while driving is a risky behavior that could be linked to a new theory on why some men act out.IntelFreePress, Flickr

Prior studies have found genetic links to risk-taking tendencies among both men and women, so some of the "crazy bastard" behavior appears to be hard-wired.

As for why men tend to engage in it more than women, Fessler explained that there is greater variance in male reproductive success than in female reproductive success. This is a consequence of the greater female investment in reproduction, due to pregnancy and lactation. Young men tend to become less risk-prone as they get older. They essentially grow out of it.

Daniel Kruger, a researcher and faculty member of the University of Michigan"s School of Public Health, finds the Crazy Bastard Hypothesis "intriguing and intuitively plausible."

Kruger said, "It helps to remember that our psychological architecture evolved in a world much different from what you and I experience. Only very recently have we had rule of law and near universal police protection in modern societies."

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"Even just a hundred years ago," he continued, "people were at risk of physical confrontations both within their social group and with other groups. Having formidable allies and creating a deterrent to threats were very real and prominent concerns through most of human history."

Such concerns live on to this day.

Fessler said that women who feel that they are in need of physical protection tend to go after daredevils, while certain countries tend to always support "Crazy Bastard" leaders.

"As for electing leaders," Fessler said, "if one lives in a setting where violent conflict occurs between groups, then one should place greater value on having a leader who will intimidate enemies."