flathead catfish (IMAGE) Penn State Caption To determine what the flathead catfish were eating, researchers collected 576 of them over two years, with 241 individuals having recoverable stomach contents. The researchers extracted DNA from those contents and identified prey tissues. Credit Julian Avery/Penn State Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND 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.