On Wednesday, the Santa Cruz Museum of Natural History announced that it's now in possession of a prehistoric left arm bone belonging to a Jefferson’s ground sloth (Megalonyx jeffersonii ...

Their discovery turned out to be a prehistoric left arm bone of an ancient Jefferson's ground sloth (known as Megalonyx jeffersonii). The fossil is believed to be between 11,500 and 300,000 years old.

New research painted a more accurate picture of the megafauna that spread widely around the Americas before they went extinct.

New research revealed that the first humans to arrive in the Americas lived alongside giant ground sloths for thousands of years, challenging previous theories about human migration and megafauna ...