ARCHAIC HUMANS AND MODERN HUMANS INTER MIXING AS LITTLE AS 50K YEARS AGO

Plus Archaic Humans mixing with each other: 
Denisovans and Neanderthals in Asia. David Reich.

This was Reich's Introductory talk, in Seattle:

https://www.youtube.com/watch?v=fHdCuhYRHqo

You can't not drink it: It is hard science, baby!