Evolved Tolerance (IMAGE) Rensselaer Polytechnic Institute Caption Zooplankton descended from populations previously exposed to road salt for 5-10 generations (2.5 months) were more likely to survive concentrations as high as 1,300 mg chloride per liter. Credit Rensselaer Polytechnic Institute 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.