The shape of your face can give other clues to your behavior, and can also help you pick up on clues that alert you to danger.

Imagine a thug, says an article published in The Conversation. Chances are you will have imagined him as a man with a short wide face. It's not by chance, say the authors of a study that examined the connection between face shapes and personality.

The study, which was published in PLOS ONE, examined 56 research papers and found that a clue to the ability to quickly identify potentially dangerous people lies in their facial width-to-height radio.

The researchers found that men with larger width-to-height ratios, that is shorter, wider faces —more square — exhibited more threatening behaviors. They were more aggressive, more prejudiced, and more likely to lie than people with longer, more narrow faces. The results only applied to men.

However, both men and women with larger width-to-height ratios were more dominant than men and women with smaller ratios. For instance, people with larger width-to-height ratios agreed more with the statement, "I often try to get my own way regardless of what others may want."

According to the authors, one study analyzed 29 U.S. presidents and found that those who had a larger width-to-height ratio appeared to have a stronger drive to succeed.

Other studies found that men with more square faces were more likely to succeed in business and sports.

The larger width-to-height ratio appears to be linked to higher levels of testosterone, a hormone implicated in dominant behavior, say the authors.

Although the link between face shape and behavior isn't strong, we perceive the relationship to be stronger than it is, and that may have saved our lives in the past.

"All mammals must figure out whether other organisms are likely to harm them," the authors wrote in The Conversation. "Doing so quickly would have significant advantages: the cost of making a mistake could result in death, but overestimating the danger is relatively cost free (other than a little anxiety, or missing out on a potentially fruitful friendship).

"So even if there is only a small chance of being attacked, overestimating the relationship between the facial width-to-height ratio and danger could be a life saver."