Research supports correlation between finger lengths and stress hormones

If you find yourself lacking in motivation to go for a run or hit the gym, you may want to check your fingers. According to a joint University of Alberta/ University of California- Riverside research study to be published by PLoS ONE, the online, open-access journal from the Public Library of Science, there is a direct correlation between digit length and voluntary exercise.

The study also casts some doubt on a previously released study which linked digit length and male aggression.

While both situations were first thought to have been caused by exposure to elevated levels of prenatal testosterone in the womb, research conducted using lab mice yielded no concrete evidence to support that original hypothesis.

The new study, conducted using 1,000 white mice, seems to support a stronger connection between digit length, voluntary exercise and high levels of prenatal stress hormones, which was indicated by the difference in activity level between the control mice and the selectively-bred active mice. Given the results, the findings suggest that prenatal stress rather than prenatal testosterone levels in the womb, forms a component of the inherent desire for physical activity.

"The research shows a link, or relationship, between the brain, behaviour and personality traits and the shape of the hand," said Peter Hurd, University of Alberta psychology professor and one of the lead researchers. "It opens the door to the notion that aspects of one's personality, in this case the desire to exercise, are fixed very early in life."

Citation: Yan RHY, Malisch JL, Hannon RM, Hurd PL, Garland T Jr. (2008) Selective Breeding for a Behavioral Trait Changes Digit Ratio. PLoS ONE 3(9): e3216. doi:10.1371/journal.pone.0003216 dx.plos.org/10.1371/journal.pone.0003216

Source: Public Library of Science