Long in the tooth
Science & Tech Long in the tooth Kevin Uno (left) and Daniel Green look at fossil samples in the lab. Photo by Grace DuVal Clea Simon Harvard Correspondent July 9, 2025 5 min read Research finds 18-million-year-old enamel proteins in mammal fossils, offering window into how prehistoric animals lived, evolved Proteins degrade over time, making their history hard to study. But new research has uncovered ancient proteins in the enamel of the teeth of 18-million-year-old fossilized mammals from Kenya’s Rift Valley, opening a window into how these animals lived and evolved. In their new paper in Nature, researchers from Harvard and the Smithsonian Museum Conservation Institute discuss their findings. “Teeth are rocks in our mouths,” explained Daniel Green, field program director in the Department of Human Evolutionary Biology and the paper’s lead author. “They’re the hardest structures that any animals make, so you can find a tooth that is a hundred or a hundred million years old, and it will...