Migration Mystery: Who Were the First Americans?

Not so long ago there was a simple and seemingly incontrovertible answer to the question of how and when the first settlers made it to the Americas. Some 13,000 years ago, a group of people from Asia walked across a land bridge that connected Siberia to Alaska and headed south.

These people, known to us as the Clovis, were accomplished toolmakers and hunters. {snip}

For decades this was the received wisdom. So compelling was the Clovis First model that few archaeologists even contemplated an alternative. Some with the temerity to do so complained of a “Clovis police”, intent on suppressing dissent.

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