EDMONTON, Alberta, March 3 (UPI) -- Canadian scientists say a man's finger length can predict how physically aggressive he is likely to be.
Psychologist Peter Hurd of the University of Alberta, in a study published this month in the journal Biological Psychology, reviewed surveys and conducted hand measurements on 300 students to predict how inclined a man is to be physically aggressive.
Hurd said it has been known for more than a century that the length of the index finger relative to the ring finger differs between men and women. More recently, researchers have found a direct correlation between finger lengths and the amount of testosterone a fetus is exposed to in the womb.
The shorter the index finger relative to the ring finger, the higher the amount of prenatal testosterone, and -- as Hurd and an associate have now shown -- the more likely he will be physically aggressive throughout his life.
"More than anything, I think the findings reinforce and underline that a large part of our personalities and our traits are determined while we're still in the womb," Hurd said.
