Look into the "japanese ainu people" and their genetic history. Their only living relatives according to dna testing are a few isolated island groups who are still black. They look like europeans, but are a second evolution of the lineage due to winter adaptation. This adaptation also occured in china, but they were purged over the course of china's long history of purging different people within their borders. China also did the same with a muslim city along their western border. Rounded up all males, sent them to re-education camps, which they never returned from, and the city is now covered in chineese signs and advertizements, and not a single muslim is to be seen. Only the pale pointed eye faces of chineese now walk the streets.