Length of finger holds key to your manliness

Length of finger holds key to your manliness

A glance at your boy’s relative length of index to ring finger can tell whether he would look masculine, a new study has suggested.

Researchers at the University of Vienna found that if a boy has low finger length ratio, or digit ratio, where the index finger is shorter than the ring finger, it indicates that he was exposed to high testosterone levels before birth that can lead to “manlier” faces even before he hits puberty.

Before a baby is born, testosterone seems to have what the researchers call an “organising effect” on the face and also controls how other parts of the body, including the sex organs and fingers, develop, the researchers said.

This means, they said, digit ratio can be used to measure testosterone exposure before birth, which comes from the mother and the developing baby, LiveScience reported.
Past studies on digit ratio and adult male faces showed that the lower the ratio the more “robust” the man’s face is, the researchers said.

The new finding, published in the journal Proceedings of the Royal Society B: Biological Sciences, suggests this robust and masculine face is already present before puberty, since prepubescent boys with low digit ratio have features of a characteristically masculine face. For the study, the researchers studied a group of 17 boys aged between four and 11 years, and measured their finger lengths, and took images of their faces.

They digitised these images by marking 70 measurement points to compare the face shapes. Analysing the data on the computer, the researchers were able to see what parts of the face could be linked to digit ratio, and how strongly they were correlated.

They saw that prenatal testosterone levels account for about 15 per cent of the variety in a boy’s face shapes. The researchers found that low digit ratio corresponded to this “robust” masculine face with a more prominent jawline and smaller eyes, even before puberty hits. And boys with higher digit ratios have smaller chins and larger foreheads and eyes, what the researchers refer to as a “more childlike/female appearance”.

“The overall shape patterns associated with high and low digit ratios depicted in our sample of boys closely resemble the ones found for adult men,” study author Sonja Windhager, an anthropologist at the University of Vienna, said.