Small Fossilized Snails (IMAGE) University of Texas at Austin Caption These are fossilized snail shells from the time period directly following the end-Permian extinction. The 20 cent Euro coin is for scale. Credit William Foster/The University of Texas at Austin. Usage Restrictions Credit photo 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.