Kuehn Research Image Evolutionary Trajectory (image) University of Illinois College of Engineering Share Print E-Mail Caption This is a 3-D graph depicting evolutionary trajectories constrained by a phenotypic trade-off. Credit Image by David T. Fraebel, U. of I. Department of Physics and Center for the Physics of Living Cells. Usage Restrictions None Share Print E-Mail 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.