Follow the DNA.
Well, it isn’t a Gannett source after all (I was thinkin’ USA Today), so here’s an excerpt:
“After years of spirited debate over how and when people first reached the Americas, scientists finally seem poised to reach agreement. The emerging consensus: In contrast to what was long held as conventional wisdom, it now seems likely that the first Americans did not wait for ice sheets covering Canada to melt some 13,000 years ago, which would have allowed them to traipse south over solid ground. Instead, early nomads might well have traveled by boat or at least along the coast from Siberia to North America, perhaps navigating arctic waters near today’s Bering Strait. The telltale evidence: ancient DNA from those early people that’s been coaxed, by powerful analytical technology, into revealing its secret.”