The so-called races that humans have been grouped into are cultural constructs and can not be reliably used to distinguish different ethnographic and/or cultural groups and definitely cannot be used to separate people into distinct biological groups. Variations in melanin is notoriously variable throughout the world - not specific people of African descent. Anyone that believes racial groupings are valid is a racist. Sam Clemens was a racist, but as he got older the differences in the so-called racial distinctions became less important to him - except perhaps for a possible sense of guilt. He most definitely maintained that Native Americans were an inferior peoples. Adventures of Huckleberry Finn remains my favorite all-time book. -- /Unaffiliated Geographer and Twain aficionado/