by Matt Sitman
Michael Lemonick profiles the work of archaeology professor James Adovasio, whose excavations of the Meadowcroft Rockshelter in western Pennsylvania helped upend our ideas about the peopling of North America:
A young archaeologist at the University of Pittsburgh, he intended to use Meadowcroft to train students. But what he found here helped demolish his colleagues’ long-held ideas about the timing of humans’ first steps in the New World. Since the nineteen-thirties, the conventional wisdom had held that humans crossed over into North America from Siberia around thirteen thousand years ago, then spread over the next five hundred years through North and South America—wiping out mammoths, mastodons, and other large mammals as they went. This hypothesis became known as the “blitzkrieg model” of species extinction.
But Adovasio, now a professor at Mercyhurst University, in Erie, Pennsylvania, discovered evidence that humans had camped at Meadowcroft, under a protective rock overhang, sixteen thousand years ago—a few thousand years before the Siberian crossing.
Adovasio at least partly blames old-fashioned prejudices for the persistence of the theory he rejects:
In part, he attributes the longstanding acceptance of this implausible story to the fact that, until relatively recently, most archaeologists were men. “I mean, who but a male would think that the ancestors of modern Native Americans sprinted to South America and killed everything in their path?”
If the first immigrants did arrive much earlier, the ice-free corridor through the glaciers wouldn’t have been available. But there’s an alternate route: they could have travelled down the coast in boats. “The colonization of Australia occurred even earlier,” Adovasio said. “It’s, in my opinion, simple racism that we never recognized before that the earliest populations in the Americas were capable of building boats.”