Generally speaking, racism will use any tool that is handy. And if cultural evolutionism seems to imply that Europeans are biologically superior to native Americans, then it is a handy tool. Still, it is important to understand that, logically, cultural evolutionism implies no such thing. The psychic unity of humankind is the reason that around the world, on every continent, cultural evolution has moved in the same direction. The arrow of human history begins with the biology of human nature.
Interdependence expands, and social complexity grows in scope and depth.
The ancestral cultures of all modern societies were hunter-gatherer cultures. Archaeologists have found their remnants their spearheads and stone knives, the fireside bones of their prey across Africa, Europe, Asia, the Americas. But archaeologists can't reconstruct the social lives of these peoples in much detail. Kung San of southern Africa to the Ainu of Japan, from the aborigines of Australia to the Eskimo of the Arctic, from the Fuegians of South America to the Shoshone of North America. To study these vanishing mostly vanished ways of life is to dimly glimpse the early stages of our own cultural evolution.