Finger length can reveal a man's aggressiveness

To investigate the relationship between the ratio of the index finger to the ring finger and physical aggression, the researchers asked 298 psychology students to complete questionnaires on aggression measures. The questionnaires measured four types of aggression.

The smaller the ratio of the index finger to the ring finger, the more aggressive the man is.

The results of the study show that the smaller the ratio of the index finger to the ring finger, the more aggressive a man is, but not other types of aggression. Moreover, this research result only applies to men and has nothing to do with women.

Researchers explained that male testosterone is an important factor in determining whether a man is aggressive. The study found that if male fetuses are exposed to high levels of testosterone in the womb, their index fingers will be shorter than their ring fingers. A shorter index finger in men may indicate that the fetus was exposed to higher levels of testosterone in the womb, which would lead to an increased tendency for males to attack humans when they grow up. In addition, testosterone and finger length may also be affected by a "mysterious third variable." But no matter what, this study still shows that changes in testosterone levels in the womb have a subtle effect on children's personality.

Finger ratios 'just one of the things that confuses people'

The researchers cautioned that the findings suggest that while the ratio of the index finger to the ring finger is associated with aggressive tendencies, it does not mean that men with smaller ratios are more aggressive, and some may never do anything aggressive to others. In addition, human behavior is influenced by many other factors, and the ratio of fingers "is just one thing that confuses people."