There is now proof of racial differences in form of genetic evidence.

The two and three allele version of the MAO-A gene, which is associated with violence, shows up much more often among Blacks than Whites. Crime statistics have Blacks committing about half the murders in the U.S. even though they are only 14 percent of the population.

It's been known for generations that Blacks have a smaller average brain size than Whites, but this truth has been brutally suppressed by the Jewish media, politically correct public schools and gutless politicians.