Researchers from Florida State University recently uncovered evidence that places humans in North America nearly 1,500 years earlier than what archaeologists previously believed. A stone knife, mastodon bone, and other animal bones were found in a sinkhole in Florida’s Aucilla River near Tallahassee. Radiocarbon dating shows that the items existed 14,500 years ago, much earlier than when the “Clovis People” lived—or whom archeologists believed, for 60 years, were the first North Americans. Between 2012 and 2014, researchers dove into the sinkhole more than 800 times before publishing the results of their findings in Science Advances. For more information on the findings, watch the video at the bottom.

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