Why would you even want to be on that sub

We can oppose racism on a moral, logical and ethical basis, but it's ridiculous to suggest that there is no biological basis for it to exist. Are you saying racism was invented in the 1500's or something? Evolutionary biology shows us that groups were most likely to survive if they were ethnocentric. If they didn't, they would either mingle with other groups or refuse to help their own, causing them to cease to exist as a distinct tribe. It's why we still have Bantu Hutus and Nilotic Tutsis in Rwanda thousands of years after the Bantu expansion. Besides, this is in no way a "leftist" position. It would be if you started to assign blame and so on, but acknowledging a simple consequence of Darwinian theory doesn't make someone literally Stalin.