Finger Length Can Predict Achievement

Exposure to high levels of testosterone in the womb can play a role in determining success in certain forms of financial trading.

March 12, 2009

(originally published by Booz & Company)

Title:
Second-to-Fourth Digit Ratio Predicts Success Among High-Frequency Financial Traders
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Authors:
John M. Coates, Mark Gurnell, and Aldo Rustichini

Publisher:
Proceedings of the National Academy of Sciences, vol. 106, no. 2

Date Published:
January 2009

Could success as a securities trader be a function not of intelligence, experience, or preparation, but rather of biology? Yes, say the authors of this study, who tracked the performance of 44 traders at a London exchange, all of them male, for nearly two years. The researchers focused on brokers who specialized in “high frequency” trading, a physically taxing job that entails the buying and selling of securities, sometimes in a matter of seconds. To determine whether some traders were biologically predisposed to excel in such a demanding work environment, the researchers looked at an unlikely predictor: the length of the traders’ ring fingers. Scientists have previously shown that when a male fetus is exposed to high levels of testosterone in the womb, as can be indicated by the length of the ring finger in relation to the index finger, it can lead to greater success in competitive sports. The authors of this paper hypothesized that the same phenomenon may predict performance on the trading room floor. After examining the P&L statements of each trader over 20 months, the authors found that traders with longer ring fingers earned 11 times as much as those with similar work experience but shorter fourth digits. They thus conclude that prenatal testosterone levels were as important a predictor of a trader’s long-term success as his or her experience on the job.

Bottom Line:
Exposure to high levels of testosterone in the womb can play a role in determining success in certain forms of financial trading.