Tinguiririca River Valley (image) American Museum of Natural History Caption This photo is of the Tinguiririca River valley in the Andes Mountains of Chile, where the research team discovered the newly named rodent fossils. Credit D.A. Croft/Case Western Reserve University Usage Restrictions Credit required 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.