Isotopic Ecology (IMAGE) University of Barcelona Caption The analysis of stable carbon and nitrogen isotopes aims to compare the structure of the trophic networks of the late and modern Holocene. Credit María Bas/ Lluís Cardona (UB-IRBio) Usage Restrictions The image may only be used with appropriate caption or credit. License Licensed 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.