Multituberculate Teeth (IMAGE) University of Washington Caption The teeth of multituberculate mammals evolved from simpler dentition around 150 million years ago (top) to a substantially more complex form by the time dinosaurs died out 66 million years ago (bottom). Blade-like teeth farther forward in the mouth, at right in each image, became continually less prominent in plant eaters. Credit Gregory P. Wilson/University of Washington Usage Restrictions News use only. 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.