According to folklore, blondes are pretty dumb as in the Marilyn Monroe film Gentlemen refer blondes. Not so, according to Jay Zagorsky, Prof of Economics at Ohio State University. According to the Longitudinal Survey of Youth 1979 those between 14 and 21 who later took the US Armed Forces IQ tests gave the following results: blondes 103.2; brown hair 102.7; redheads 101.2; black hair 100.5.
It’s a nonsense that all of the hair colours should be above 100; there should be as many below 100 as above. Hair colour is dependent on two or three genes at the most. They have no correlation with brain genes that have multiple associations with other genes when developing in the foetus.
It is not a fact that half the population with IQ less rhan 100 have hair which has no colour at all! The study, published in Economics Bulletin should have been returned to sender.