VANLUE, Ohio - The discovery of prehistoric tools from an Ohio cave is one of several finds that has scientists questioning the identity of settlers thought to have moved in 11,000 years ago.

A just-completed excavation of Sheriden Cave in Wyandot County revealed tools made from flaked stone and bone. Kent State University archaeologist Kenneth Tankersley, who led the excavation over the past four years, said definite answers won't come until someone finds an Ice Age skeleton and the DNA is tested.

"Disagreement swirls around the timing of their arrival, the nature of their migration, how fast they moved across the landscape and their relationship to contemporary Native Americans," he said.

Some scientists think that the earliest colonizers could have started out somewhere in Europe, not in Asia as previously thought. That idea is rooted in a rare genetic link called haplogroup X - DNA passed down through women that dates back more than 30,000 years.

Recent genetic samples from remains in Illinois show that the rare European DNA was around centuries before European exploration. Today, haplogroup X is found in about 20,000 American Indians.

To some researchers, its presence suggests the Mongolian ancestors of most American Indians were latecomers.