Hydra Regeneration (video) Cell Press Share Print E-Mail Loading video... Caption This video shows the regeneration of a hydra, starting with the ball stage all the way through full development. Credit Livshits and Shani-Zerbibet al. Usage Restrictions Credit Required. Share Print E-Mail 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.