The DNA analysis of the human remains found in Tianyuan in Beijing showed that it belonged to a person who lived 40,000 years before present. It also showed that today's Asians and Native Americans could trace their ancestry to the likes of that man of that time. My article written on that report was published earlier here:
Yet another article written by me sheds more light on the movement and mix-up of people in Sundaland – China – Siberia corridor. It can be read here:
The movement of people in the immediate past, say within 3500 to 5000 years BP is shown below.