I came across this when reading the works of Charles Darwin. Race originally meant a significant variation within a species and it didn't just refer to people but to other animals and plants. Darwin used it this way when he talked about different races of farm animals. Now we talk about race in reference to the human animal. And we refer to different breeds of animals and different varieties of plants but the principle is the same. That being the case is why I think it is improper to speak of a human race because all humans cannot be a significant variation from all humans.
And your comment about how we came by pale skin is not quite right. I like to watch archeology shows and shows about the evolution of life including people. Both homo sapiens and neanderthals evolved from the same common ancestor. Homo sapiens evolved in Africa and because of the amount of sunlight, evolved dark skin. About that time a group of those common ancestors migrated to Europe and evolved into Neanderthals. Because of less sunlight they evolved pale skin. Later homo sapiens started to migrate to Europe and were able to interbreed with neanderthals because different species of primates can interbreed if they have a common ancestor within the past 2 million years. That is how homo sapiens in Europe picked up the gene for pale skin among a few other traits.

Race is a word that was chosen to divide groups of people and in doing so created dissension that is now described a racism.

I have heard it said that. The average family of chimps, has more genetic diversity than the whole human species.