A consistent belief in evolution, natural selection, survival of the fittest, etc. would seem to be possible only for those who believe that there is no God who created all things, etc.
From the standpoint of someone who believes in the survival of the fittest [which is not what I believe], how would so-called racism be wrong since it promotes the idea that some so-called races are better than others?
If you believe that humans in their so-called races evolved to be the way they are, how can you hold that it is wrong for the so-called superior races to do what is the way everything supposedly works (natural selection, etc)?
Disclaimer: I believe what the Bible teaches about God, creation, the Golden Rule, etc and hold that evolution, natural selection, survival of the fittest, superior races, etc. are all false views.