Old Leaf (IMAGE) Columbia Climate School Caption A 23-million-year-old leaf preserved in a onetime New Zealand lake bed, key to past atmospheric conditions. One can see veins, glands along the teeth, and holes gnawed by insects, with resulting stunted growth and scar tissue. Credit Jennifer Bannister/University of Otago Usage Restrictions Credit must be given. 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.