Story highlights Finger size, rather than hand size may give a clue about a man's genitals

Hormone exposure in the womb may determine finger and penis size

(CNN) Republican candidate Marco Rubio wandered into a recent debate perhaps more fitting for the playground than a political battleground when he criticized the size of Donald Trump's hands. The Republican front runner, now famously, struck back in the debate reassuring voters that there was "no problem" with the size of his hands, or anything else for that matter.

The candidates were playing off an age-old assumption that if a man's hands were small so must be the size of his penis. The source of Rubio's comment refers back to a 1988 Spy magazine article that called Trump a "short-fingered vulgarian," perhaps insulting both his tongue and his manhood.

As a medical story, this is low-hanging fruit, so to speak, but given the pervasiveness of the myth (or reality), we decided to investigate what the science says on the matter. If this were a political reality check story our meter would be stuck on "half true."

Republican candidate Donald Trump reassures voters there was "no problem" with his hands or anything else for that matter

Sifting through a handful of studies we can conclude that while you won't see the size of a man's hands listed on a Tinder profile any time soon, a description of a man's fingers may actually give you a tiny, and we mean tiny, bit of insight.

One finger, and no, not the middle one, holds the key. If a man's ring finger is longer relative to his index finger, chances are his penis is slightly longer than average. By "slightly" we mean a difference of centimeters, in a game normally scored by inches.

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