Fossil hunters have been finding samples of Illinois' state fossil in the Mazon Creek area for decades but no one has ever been able to say exactly what a Tully monster is. A recent paper published in the journal Nature adds new insight.
Researchers who include Field Museum paleontologist Scott Lidgard have found a primitive precursor to a backbone in Tully monster fossils. That makes it a vertebrate and a potential link in the search for the origins of vertebrates.
Lidgard says the discovery is also personally important since he's always wondered what the soft-bodied Tully monster really is.
Colleen Schmidt works at Mazonia-Braidwood State Fish and Wildlife Area about 50 miles southwest of Chicago. She says people still regularly find fossilized Tully monsters and other prehistoric creatures.
