Races are inherently different, National Review writer notes. Opinion Column on Human Sciences That there are natural, intractable differences between the human races seems apparent to me on both rational and empirical grounds. First, the rational grounds. If a species is divided into separate populations, and those populations are left in reproductive isolation from each other for many generations, they will diverge. If you return after several hundred generations have passed, you will observe that the various traits that characterize individuals of the species are now distributed at different frequencies in the various populations. After a few ten thousands of generations, the divergence of the populations will be so great they can no longer cross-breed; and that is the origin of species. This is Biology 101. Our species separated into two parts 50, 60, or 70 thousand years ago, depending on which paleoanthropologist you ask.++ One part remained in Africa, the ancestral homeland. The other crossed into Southwest Asia, then split, and re-split, and re-split, until there were human populations living in near-total reproductive isolation from each other in all parts of the world. This went on for hundreds of generations, causing the divergences we see today. Different physical types, as well as differences in behavior, intelligence, and personality, are exactly what one would expect to observe when scrutinizing these divergent populations. Now, the empirical grounds. We all notice the different physical specialties of the different races in the Olympic Games. There was a run of, I think, seven Olympics in which every one of the finalists in the men's 100 meters sprint was of West African ancestry — 56 out of 56 finalists. You get less pronounced but similar patterns in other sports — East African distance runners, Northeast Asian divers, and so on. These differences even show up within sports, where a team sport calls for highly differentiated abilities in team members — football being the obvious example. We see the same differences in traits that we don't think of as directly physical, what evolutionary psychologists sometimes refer to as the "BIP" traits — behavior, intelligence, and personality. Two of the hardest-to-ignore manifestations here are the extraordinary differentials in criminality between white Americans and African Americans, and the persistent gaps in scores when tests of cognitive ability are given to large population samples. There is a huge academic literature on the gaps in cognitive test results, practically all of it converging on the fact that African American mean scores on cognitive tests fall below the white means by a tad more than one white standard deviation. There is in fact so much data on this now that we have meta-studies — studies of the studies: the one best-known to me is the meta-study by Roth et al. in 2001, which covered 39 studies involving nearly six million test-takers. That one standard deviation on cognitive testing has been so persistent across so many decades, a friend of mine, an academic sociologist, calls it "the universal constant of American sociology" — it's like the speed of light in physics.