<HTML>Hi Jason,
Good post. If I can make one correction.
>Also, new theories reject the land-bridge hypothesis and postulate that
>America was populated by sailors sliding down the Ice Age coasts, now
>underwater.
There is evidence that people used both the inland (i.e. centre of the land bridge) and the coastal (travelling along the coast of the land brdige and subsequently down the coast of Alaska, Canada and into America. Those that came by the coast probably possessed canoe-type small vessels.
There is debate over the 30 000 BP date. The genetic evidence supports it but there are questions over the physical and anatomical evidence. It remains plausible that there was a small earlier migration into the Americas at around 30kya (which would explain the current low archaeological visibility) who were later subsumed into the larger number if immigrants, to whose genetic make-up they also contributed.
American archaeology is very complex and it's a pity that more non-American scholars don't pay more attention to it and it's also a pity there's a little bit of a bias amongst North American archaeologists towards sites and dates from South America.
Mike.</HTML>
