Staffan Persson (IMAGE) University of Copenhagen - Faculty of Science Caption Professor Staffan Persson of the University of Copenhagen’s Department of Plant and Environmental Sciences Credit Staffan Persson Usage Restrictions The image may be used with appropriate caption and credit 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.