A Triceratops may have been the last dinosaur standing, according to a new study that determined a fossil from Montana's Hell Creek Formation is "the youngest dinosaur known to science."
The Triceratops, described in the latest Royal Society Biology Letters, dates to 65 million years ago, the critical period of time associated with the Cretaceous-Tertiary (K-T) extinction event that wiped out all non-avian dinosaurs and many other animals and plants.
Since this rhinoceros-looking, three-horned dinosaur lived so close to the mass extinction moment, it could negate an earlier theory that dinosaurs gradually died out before 65 million years ago.
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"Our paper suggests that dinosaurs did not go extinct prior to the impact," lead author Tyler Lyson told Discovery News. "The fact that this dinosaur is so close to the K-T boundary lends support to the idea that they went extinct as a result of a meteorite impact."
Lyson, a researcher in Yale University's Department of Geology and Geophysics, and his team discovered the remains of the Triceratops, including its over 1.5-foot-long horn, just 5 inches below the pollen-calibrated K-T boundary at Camel Butte, a hill at the Hell Creek Formation in southeastern Montana.