The extra millimetres on that digit are caused by a burst of male hormone testosterone whilst in the womb.
The study looked at the hands of 50 young men in long-term relationships then took the vital statistics of their partners. The researchers found that men with ring fingers longer than their index fingers and women with small waists would often gravitate towards each other.
"Our results suggest men's pre-natal environment has an impact on the likelihood of being in a relationship with a more attractive and presumably more fertile woman. Men with [longer ring fingers] were four times more often partnered with women who had both relatively narrow waists and large breasts," explained the study.
Lead author, human behaviour expert Berenika Kuna, added, "Eye-tracking studies have shown that, during evaluation of female body attractiveness, men focus mainly on the waist and breast areas, which deliver honest signals about a woman's reproductive status. A narrower waist in relation to wider hips is a visual sign of healthiness and youthfulness. Larger breasts may be a sign of sexual maturity and nurturing ability. However, mainly in Western cultures, they are considered a sign of attractiveness."
Men with longer ring fingers have also been found to have better spatial abilities - while those with shorter ring fingers have superior verbal ability.
A longer ring finger isn't the only side-effect of extra testosterone exposure.
Others include being more muscly and athletic, having more powerful grips regardless and better spatial abilities. (ANI)