Matsuo (IMAGE) PLOS Caption Genes expressed at the tip of fruit flies' legs determine which host plant they choose as their breeding grounds. Credit Image: T. Matsuo and J. Yasukawa 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.