Scientists excavating an Ice Age ecosystem in the resort town of Snowmass Village say they have found the first Jefferson's ground sloth ever discovered in Colorado.

Denver Museum of Nature & Science research associate Greg McDonald confirmed Saturday that a bone found earlier this week is the upper arm of the Jefferson's ground sloth. He says that other sloths have been found in Colorado, but they were a different species called Harlan's ground sloth. The bone found this week is the first from a Jefferson's ground sloth in Colorado.

So far, scientists working at the site also have found a Columbian mammoth, American mastodon, Ice Age bison and an Ice Age deer.