Carbon-dating teeth suggests two large mammal species roamed ... Previous research has noted other megafauna fossils around 6,000 and 5,000 years old in the American continent and elsewhere ...

"Future paleontologist, Molly, was out searching for fossils on Christmas morning when, what to her wondering eyes appeared…but a huge Megalodon tooth!" the museum wrote on its Facebook page.

Now researchers have found other megafauna specimens, including giant sloths and camel-like ... dated fragments of teeth from different megafauna species found at two fossil sites in Brazil ...