Amos, the point I was making is that stuff moving about is not necessarily a sign of trade, but may be just as likely a sign of raiding.
It would be nice to think that there were peaceful guys dealing about the world, trading in polished jet and shell and bronze, but much of history shows more a mindset of 'He got it, me want it, smack!'

No way to tell now, of course.
I suspect early settlers weren't delicate, self-effacing people, any of them.