Archaeologists excavating a cave in the mountains of central Mexico have unearthed evidence that people occupied the area more than 30,000 years ago — suggesting that humans arrived in North America at least 15,000 years earlier than thought.

The timeline of human existence in the Americas continues to get older and older. We are just beginning to learn about our ancestors.

"Archaeologists say stone artefacts point to occupation more than 30,000 years ago — but not everyone is convinced."

“When I see a claim being made that is so dramatic, then the evidence has to be there to substantiate the claim,” says archaeologist Kurt Rademaker at Michigan State University in East Lansing.

Real