Lake Nakaumi (IMAGE) Shinshu University Caption Ostracod shells were collected from the bottom of the lake Nakaumi. Credit Katsura Yamada, Shinshu University, Japan 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.