I'm persuaded there's a connection between the Tarim mummies and Caucasian migration. Whether it originated in China and spread out from there or whether it came into China from elsewhere I'm not sure.
In Oppenheimer's book, which type of Mongoloid was found at Lake Baikal, northern or southern?
Northern. He goes on to say that the Northern Mongoloid types (via the DNA trail) derived from the Southern Mongoloids.
I should have said in the previous post that the earliest undisputed Mongoloid type ever found was 10k years old. There is one skeleton that is 21k years old that some claim is Mongoloid but the discussions become so heated about it that everyone has quit talking about it, so...
Another correction: The Southern Mongoloids do not have the epicanthic eyelid, that was apparently a Northern adaptation.