Cope (IMAGE) University of Wisconsin-Madison Caption Lead researcher Olivia Cope holds on to two aspen trees in the experimental plots. The two trees are the same age, but the larger tree is genetically predisposed to focus on growth, outcompeting its smaller neighbor. Over time, the faster-growing trees survived better, changing the genetic structure of the forest. Credit Rick Lindroth / UW–Madison Usage Restrictions None 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.