Underwater archaeologists have discovered mastodon tusks and bones showing clear signs of human tool marks at the bottom of a limestone sinkhole. This evidence suggests that early Paleo-Indians were active in the region far earlier than the traditional Clovis-first theory suggests.
The site, preserved in an oxygen-free environment, also yielded fragments of stone tools and organic remains. The discovery provides crucial data on the interaction between early humans and Pleistocene megafauna in North America.