No. 124: Jul-Aug 1999
After learning that mutations in a single gene in mice affected not only the development of their digits but also their ovaries and testes, J. Manning and his colleagues decided to see if there is a link between human hand shape and fertility. There is!
Men with hands that are not precise mirror images of each other tend to produce fewer sperm. Manning asserts, "The more asymmetry, the fewer sperm."
Easier to test yourself are the relative lengths of your ring and index fingers. Men tend to have ring fingers that are longer than their index fingers. The greater this difference in males, the higher their levels of testosterone, a hormone associated with fertility.
In women, the same fingers are usually about equal in length. However, in contrast to males, larger index fingers are correlated with the increased presence of fertility hormones, such as estrogen and lutenizing hormones.
(Motluk, Alison; "Fertility Index," New Scientist, p. 10, August 22, 1998.)
|A virile male's hand?|