<i>Science</i> Cover (IMAGE) U.S. National Science Foundation Caption The researchers' findings are described in the March 11, 2011, issue of the journal Science. Credit Copyright AAAS 2011 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.