Artifacts of ancient Americans
A sampling of the stone tools found by a team from Texas A&M University, showing that humans have been int he Americas far longer than thought previously. Michael Waters/Texas A&M

Researchers at an archaeological site have found proof that the earliest humans lived in North America far earlier than previously believed.

The researchers, led by a team from Texas A&M University, found the oldest known archaeological evidence for human occupation in not only central Texas, but North America. The discovery was made in conjunction with researchers at Baylor University, University of Illinois-Chicago, the University of Minnesota and Texas State University, at the Debra L. Friedkin site 40 miles from Austin.

Michael Waters, director of Texas A&M's Center for the Study of the First Americans, said his research team found record of human occupation 15,500 years ago, 2,500 years earlier than previously believed. The researchers found artifacts that proved Late Prehistoric and Archaic occupants lived in the region.

Most of these are chipping debris from the making and resharpening of tools, but over 50 are tools. There are bifacial artifacts that tell us they were making projectile points and knives at the site. There are expediently made tools and blades that were used for cutting and scraping, Waters said in a statement. The researchers will publish their work in an upcoming issue of Science.

The researchers used a method called luminescence dating to authentic the artifacts were 15,500 years old. This technique involves dating the sediment surrounding the artifacts, finding out the last time it was exposed to sunlight.

Prior to the research, it was widely believed the Clovis people were the first inhabitants of North America around 12,000 to 13,000 years ago. While some research has been made to disprove that theory, Waters says it wasn't concrete until now.

What is special about the Debra L. Friedkin site is that it has the largest number of artifacts dating to the pre-Clovis time period, that these artifacts show an array of different technologies, and that these artifacts date to a very early time, Waters said. This discovery challenges us to re-think the early colonization of the Americas. There's no doubt these tools and weapons are human-made and they date to about 15,500 years ago, making them the oldest artifacts found both in Texas and North America.

Credit: Texas A&M