I assume you saw the recent articles about those writings from Olmecs. I have read that Olmec could of came from the Shang Dynasty in an article you posted. I wonder if Ancient Chinese had Jomons amongst them?
I have on occasion speculated that the Mongoloids and Caucasians both may have 'sprung' from the Jomon.
Professor Stephen Oppenheimer says that the oldest (undisputed) Mongoloid skeleton ever found is only 10,000 years old.