Coral rings (IMAGE) University of Tokyo Caption A cross-sectional scan of coral reveals growth rings. These correspond to different years, so researchers can look for markers to see when certain atmospheric changes took place. Credit © 2022 Yokoyama et al. Usage Restrictions Credit © 2022 Yokoyama et al. License Original 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.