7 Milestones in the history of ‘digit ratio’!
September 28, 2008
A short history of major the developments in the concept of ‘digit ratio’:
More than a hundred years ago, a very entertaining paper concerning various customs and superstitions associated with the hand – titled: ‘Anthropological Notes on the Human Hand‘ (1888) – was presented to the Antropological Society of Washington by Frank Baker, Professor of Anatomy at the University of Georgetown. Following some fascinating tales, and a debunking of palmistry, he concluded by discussing the comparative lengths of the digits, and noted that the second (index) finger is usually shorter than the fourth (ring) finger.
Some years later R. George described in a paper – titled: Human Finger types (1930) – a sex difference in the distribution of finger length ratios in that males are more likely to show the 2 < 4 pattern (i.e. a longer ring finger relative to the index finger), while females are more likely to show the opposite pattern (2 > 4).
Two decades later the sex difference findings reported by George (1930) were confirmed in the work of V.R. Phelps – titled: Relative index finger length as a sex-influenced trait in man (1952) – noting that such differences were observed in foetuses, and then appeared to be stable throughout life.
* In 1983 Psychologist Glenn Wilson introduced the word ‘digit ratio’:
Dr Glenn Wilson of King’s College, London published a study – titled: ‘Finger length as an index of assertiveness in women‘ – which introduced the 2D/4D ‘digit ratio’ as a marker of exposure to prenatal testosterone + examining the correlation between assertiveness in women and their digit ratio. This was the first study to examine the correlation between digit ratio and a psychological trait within members of the same sex.
* In 1998 Psychologist John T. Manning presented a link between ‘digit ratio’ and testosterone + sperm counts:
This link was described by Manning in a study – titled: ‘The ratio of 2nd to 4th digit length: a predictor of sperm numbers and concentrations of testosterone‘.
* In 2002 Psychologist John T. Manning presented the book ‘Digit ratio’:
Psychologist John T. Manning presented his first book about the 2D:4D ratio – titled: ‘Digit ratio: A Pointer to Fertility, Behavior and Health‘.
In this book Manning presents a first overview of the digit ratio research which has been presented uptill the year 2002.
* In 2008 Psychologist John T. Manning presented the book ‘The finger book’:
Psychologist John T. Manning presented his first book about the 2D:4D ratio – titled: ‘The finger book‘.
Quote from New Scientist:
“According to evolutionary psychologist John Manning, who has spent years researching the secrets they betray, your digits reveal all sorts of things, from your sexuality to whether you are socially disadvantaged or likely to suffer a heart attack. They even, as the legend goes, give away the size of a man’s penis.”