David Rand and Chen-Tseh Zhu, Brown University (image) Brown University Share Print E-Mail Caption David Rand, left, and Chen-Tseh Zhu managed 18 different lines of fruit flies, feeding groups from each line five different diets. They were able to examine the effects on longevity of three different elements: diet, mitochondrial DNA, and nuclear DNA. Credit Mike Cohea/Brown University Usage Restrictions with credit 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.