There are many cases of Japanese junks (not Chinese) that randomly caught the currents and were washed ashore along the western America's coastline.
This has occurred for a very long time, and there are many stories that relate it.
Recent DNA evidence has also shown that some native Americans have distinctly Japanese heritage, although this is a small percentage and almost exclusively on the western coastline.
This evidence bodes well in backing up the findings about the pottery, and should be no surprise to those who have studied the subject in depth.
The chains of connection go much further though, and actually show that the ancient world was far more "globalized" than most commonly believe today.
We can connect ancient India with Polynesia and South America, as well as ancient African cultures with the South American Olmecs.
Even North America has connections to ancient Europe and Asia.
The Americas were truly the worlds first melting pot, far before contemporary history tells us. However the evidence clearly shows this to be the case.
Fun subject.



