The early growth of our ring finger is sensitive to levels of testosterone – the so-called “male hormone”, in the womb (as the testosterone receptors are more densely packed along the finger), and the longer our ring finger the more “masculine” we will turn out to be.
Of course, finger length is also dependent on body size, so we must compare the length of our ring finger with that of our index finger, since the index finger’s early growth is dependent on the “female hormone”, oestrogen.
The relative length of our ring and index fingers – our “finger ratio” – therefore speaks volumes about the balance of maleness and femaleness of our body and brain.
A long ring finger is not universal, but characteristic of men. A long index finger is found in many men, but overall it is characteristic of women as a group.