Manning zu Digit Ratio und Fußball:
Fetal and adult testosterone may be important in establishing and maintaining sex-dependent abilities associated with male physical competitiveness. There is evidence that the ratio of the length of the 2nd and 4th digits (2D:4D) is a negative correlate of prenatal and adult testosterone. We use ability in sports, and particularly ability in football, as a proxy for male physical competitiveness. Compared to males with high 2D:4D ratio, men with low ratio reported higher attainment in a range of sports and had higher mental rotation scores (a measure of visual–spatial ability). Professional football players had lower 2D:4D ratios than controls. Football players in 1st team squads had lower 2D:4D than reserves or youth team players. Men who had represented their country had lower ratios than those who had not, and there was a significant (one-tailed) negative association between 2D:4D and number of international appearances after the effect of country was removed. We suggest that prenatal and adult testosterone promotes the development and maintenance of traits which are useful in sports and athletics disciplines and in male:male fighting.
In seinem Buch „The Finger Book“ geht er hierauf auch sehr lange ein, weil es einer der Beispiele ist, an denen er bestimmte Punkte erläutern will. Er hat diverse Messungen näher dargestellt, die auch noch einmal auf der Seite Handresearch wiedergegeben sind:
Manning published in his books detailed reports about sample of amateurs & professionals from England, including: 304 professional players (e.g. from the Premier Division clubs: ‚Liverpool‘ and ‚Coventry City‘), and 99 players from Brazil (e.g. First Division club: ‚Sport Club Internacional‘).
The results of Manning’s reports on football players should be seen in the perspective that populations from England are known for having a relative high average digit ratio: 0.98 for males, and 1.00 for females.
A few of the reported digit ratio facts:
• Average ‚2D:4D digit ratio‘ in football amateurs (N=533) = 0.98;
• Average ‚2D:4D digit ratio‘ in football professionals (N=267) = 0.95;
• Average ‚2D:4D digit ratio‘ in football internationals (N=37) = 0.94;
• Average ‚2D:4D digit ratio‘ in black football professionals (N=13) = 0.93;
• Average ‚2D:4D digit ratio‘ in football professionals (N=99) = 0.93;
• Average ‚2D:4D digit ratio‘ in first team professionals (N=20) = 0.92;
Manning führt aus, dass man in jedem Land natürlich Personen haben kann, die eine sehr niedrige Digit Ratio haben. Aber um so niedriger die Digit Ratio im Schnitt ist, um so größer ist der Talentpool, der zur Verfügung steht, womit dann auch die Wahrscheinlichkeit steigt, dass ein Talent gefunden und genutzt werden kann (zu den unterschiedlichen Digit Ratios einige Völker (wie meist bei Artikeln zur Digit Ratio mit viel Kritik))