Fruit fly Drosophila mercatorum (IMAGE) University of Cambridge Caption Researchers have identified the genes that are switched on, or switched off, when these flies reproduce without fathers. Credit Jose Casal and Peter Lawrence Usage Restrictions With credit License Original 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.