Archaeologica.org

As Adovasio and his students bore down into the layers of silt, the cultural evidence gets older and older. By the time they hit bedrock 15 feet down, Adovasio was sending specimens for carbon dating, and the word back was staggering: at least 16,000 to 17,000 years old.

But perceived wisdom in archaeology said that people arrived in the New World relatively late, about 11,500 years ago, "signaled," as Adovasio wrote, "by the appearance of a genuine North American invention: the Clovis projective point." Could Meadowcroft really be 4,000 years older?


Adovasio and his work set off a firestorm that has raged for more than 30 years. Some archaeologists claim his samples were contaminated, possibly by nearby coalfields. After results came back from four labs around the world, with no signs of contamination and identical carbon dates, some scientists changed their minds.

"by the appearance of a genuine North American invention: the Clovis projective point.

Developing a new culture to fit the new circumstances would take a little time I think.