Archeologists have long assumed the evolutionary development of strong, thick-enameled teeth coincides with a mammals shift to a diet of field grasses. However, a new study in Nature Communications shows some Argentine mammals developed sturdy chompers in response to gritty volcanic dust that appeared in their tropical rainforest habitat. “The assumption about grasslands and the evolution of these teeth was based on animal fossils,” said co-author Caroline Strömberg, from Earth and Space Sciences. “No one had looked in detail at evidence from the plant record before. Our findings show that you shouldn’t assume adaptations always came about in the same way, that the trigger is the same environment every time.” Read the full article from Red Orbit.