Jan Taucher working on a Mesocosm (IMAGE) Helmholtz Centre for Ocean Research Kiel (GEOMAR) Caption Biological oceanographer Jan Taucher is working on a Mesocosm. Mesocosms are a type of large-volume, oversized test tube in the ocean with a capacity of tens of thousands of liters, in which changes in environmental conditions can be studied in a closed but otherwise natural ecosystem. Credit Ulf Riebesell / GEOMAR Usage Restrictions May be used for editorial purposes only, in context with this specific press release. Credits must be mentioned as follows: Ulf Riebesell / GEOMAR 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.