Dr. Saunders remembers the day well. It was May 6, 1980, when Dr. Leo Carson Davis literally picked up the fossil from a gravel bar he was standing on as they were preparing the site to excavate a mastodon. The partial skeleton of the mastodon that included a knee cap attached to the femur, a tusk and other pieces was exciting. But the piece that they thought could only be a fragment of a plastron or belly plate of a giant tortoise (along with a few other fragments) was record setting in paleontological journals.

Fillmore, Illinois is the farthest north that any signs of Ice Age giant tortoise have been found. The team dated the tortoise to the Sangamon Interglacial Period — approximately 124,000 years ago. The theory is that gulf coast winds converged more northerly to create a microclimate that suited the giant tortoise. A re-creation of the tortoise and its habitat is on display at the Changes exhibit in the Illinois State Museum, located at the intersection of Spring and Edwards streets in Springfield.

Read More Information and view photos from the dig:
Aliens Among Us
Dig Into Local History
Ice Age Giant Tortoise
Mastodon Tusk