Does your man drives a little too fast and doesn't care much about traffic rules? Well, then take a close look at his ring finger.
A new research has said that men with long ring fingers are more likely to drive too fast, overtake on dangerous roads and park illegally.
The study has indicated that bad driving may be programmed from birth because finger length is directly linked with exposure to the hormone testosterone in the womb.
Many previous studies have shown that a long wedding ring finger compared to the index finger in men can have a powerful effect on health and behaviour.
According to researchers, it is linked with increased male aggression and risk-taking.
However, it also means men are better at sports such as athletics and football, more successful in business and may even be more fertile than those with shorter ring fingers.
Scientists believe exposure to greater levels of testosterone in the womb affects the way the brain works later in life. It is believed that the hormone promotes more masculine behaviour.
But it also seems to activate growth of the wedding ring finger by stimulating testosterone receptors in bone.
In the current study, researchers at the University of Mainz, in Germany, recruited 77 male drivers at an average age of 38, who had their left hand scanned to measure the difference in length between the ring and index fingers.
Later, they had to provide details of all driving offences within the previous five years.
More than one third of the drivers reported having penalty points on their licences, ranging from one to 20, for offences ranging from speeding to drink driving.
The results showed that men with longer ring fingers were more likely to have offended.
"A longer ring finger than index finger was related to more traffic violations. Hormone exposure in the womb might increase traffic violations in later life," the Telegraph quoted the researchers as saying in a report on their findings.
The study was published in the journal Accident Analysis and Prevention.