Species' Range (IMAGE) University of Vienna Caption Species' range margins arise due to intrinsic interplay between ecological and evolutionary dynamics. The collapse of adaptation can be explained by just two dimensionless parameters -- these are depicted on the axes. Adaptation fails when genetic drift reduces genetic diversity below that required for adaptation to heterogeneous environment. Credit Polechová Usage Restrictions None 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.