To understand who we are as a species, and why we vary as we do, we must examine our genetic diversity in the context of a common African origin, fol… - Daniel J. Fairbanks

Vibrant human diversity is now commonplace in major cities throughout the world. Some celebrate such a mix of human diversity. Others deplore it, preferring that so-called races be separated both geographically and reproductively. Even today, some people retain the once-popular belief that the 'white' race is superior in intellect, health, and other attributes. Although far more people reject the notion of white supremacy today than in the past, its legacy remains, as evidenced by economic stratification, ongoing segregation, and classification by racial categories. Even among those who reject the supposed superiority of a particular ethnicity over any other, the perception of distinct, genetically determined human races often persists.

Classification is real, but it is based much more on a set of social definitions than on genetic distinctions. Legally defined categories for race differ from one country to another, and they change over time depending largely on the social and political realities of a particular society or nation. The notion of discrete racial categories arose mostly as an artifact of centuries-long immigration history coupled with overriding worldviews that white superiority was inherent, a purported genetic destiny that has no basis in modern science.

Under the guise of eugenic improvement and racial purity, and what the implementation of eugenic measures could supposedly do to improve human society, notions of racial superiority continued in popularity, but with a purported scientific foundation.