Second-to-fourth digit ratio predicts success among high-frequency financial traders

"We found that 2D:4D predicted the traders’ long-term profitability as well as the number of years they remained in the business. 2D:4D also predicted the sensitivity of their profitability to increases both in circulating testosterone and in market volatility. Our results suggest that prenatal androgens increase risk preferences and promote more rapid visuomotor scanning and physical reflexes."

PNAS article - Coates et al. (2009)