A pet peeve of mine is that a lot of non-black men in the HBD blogosphere believe everything that professor J. Philippe Rushton said about ethnic differences in IQ and brain size, but when it comes to black men having the largest penis size, they suddenly turn into HBD deniers, ranting and raving about how the research is wrong. Well, I’m sorry but HBD is not here to serve your racist supremacy, HBD is here to celebrate ALL RACES, NOT YOURS ONLY!!!! If the data shows that black men have the largest penis size, then shut up and get over it. What kind of man gets jealous over another man’s penis size anyway? A sick, twisted, perverted sinful one. Healthy well adjusted normal guys don’t even know how large their penis is, and couldn’t care less, because they have other things going for them like a girlfriend, a career, and sports, and their mind’s not in the gutter. The only legitimate reason to care is for science, so here are the FACTS:
According to data from the World Health Organization Global Programme on AIDS Specification and Guidelines for Condom Procurement (1991, p 33, Table 5), assuming a normal distribution, I estimate the average white American man has a penis length of 162 mm (SD = 19) , and the average African American man has a penis length of 170 mm (SD = 19). (since 5% of black men are longer that 200 mm, and 2% of white men are, while 27% of white men have penises shorter than 151 mm, while 15% of black men do).
But small differences is the mean have huge implications at the extremes. Assuming a normal distribution, one in 3.4 million African American men would have a penis length > 264 mm, vs only one in about 30 million white men.
What about penis circumference? Once again, black men come out on top. 9% of African American men are > 150 mm, while only 5% of white American men are. Only 2% of men in either race are < 75 mm. Assuming a normal curve, that implies white American men have a mean penis circumference of 117 mm (SD = 21), while black American men have a mean penis circumference of 121 mm (SD = 23). Note the larger SD in black men; they not only have a higher mean, but more variability. This means that black men will be dramatically over-represented among the thickest penises in America, and among the ten thickest in America, 100% should be black; unless some non-black man has some kind of freak mutation.
When it comes to scrotal circumference, I don't have exact figures, but Rushton cites scholars showing that Africans exceed Europeans: Short, 1979; Ajmani, Jain & Saxena, 1985.