Marimo. (IMAGE) University of Tokyo Caption A researcher takes samples of algae filaments from the marimo ball. The ball is made up of green algae throughout and doesn’t have a different material at its core. Credit 2022 Akina Obara Usage Restrictions Credit must be given to the creator. License CC BY 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.