Casey Holliday (IMAGE) University of Missouri-Columbia Caption Casey Holliday, an associate professor of anatomy in the MU School of Medicine, and a team of researchers found that crocodiles -- and even their plant-eating ancestors -- had thin tooth enamel, a trait that is in stark contrast to humans and other hard-biting species. Credit University of Missouri Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.