Figure 1 (IMAGE) Tohoku University Caption Two fish swimming at short distances interact via vortex flow and synchronize their tailbeat, resulting in a significant reduction of energy consumption. Credit Susumu Ito Usage Restrictions Reporters may use freely these materials in news coverage with appropriate credit information. 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.