Here are eight of the most intriguing pieces of pre-Clovis evidence. One of the first sites to undermine the Clovis-First theory was a rock shelter, known as Meadowcroft, found deep in the forest ...

In recent years, however, researchers have unearthed many sites that appear to be pre-Clovis, some of them potentially doubling the time frame people have been in the Western Hemisphere.

But others kept offering data that the Americas were inhabited before Clovis. The vituperative debate ended only when strong evidence for a pre-Clovis settlement turned up in Chile in the late 1990s.

“Unless and until numerous discrepancies in the final report are convincingly clarified, this site should not be construed as conclusive proof of a pre-Clovis occupation in South America.