Mountain gorilla chewing plant in wild (IMAGE) University of California - Davis Caption Mountain gorillas spend much of their time chewing and spitting out plants. Veterinary scientists found that collecting and analyzing the discarded plants can help them detect viruses. Credit Tierra Smiley Evans/UC Davis 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.