A recent geological study revealed that Utahraptor, the largest known “raptor” dinosaur, is 10 million years older than previously thought, now estimated to be 135 million years old. This discovery impacts the understanding of dinosaur evolutionary history and bridges a significant gap in the rock record between the Jurassic and Cretaceous periods in Utah. The study, co-written by Gregory Ludvigson from the University of Kansas, examined the Stikes Quarry at Utahraptor Ridge—a site rich with well-preserved dinosaur fossils. Researchers utilized uranium/lead dating of zircon crystals and analyzed stable carbon isotopes to establish the revised age. This research indicates that the fossil-rich rocks are part of a geological unit deposited during a significant global change event known as the Weissert Event, highlighting the implications for our understanding of ancient ecosystems. The findings also reduce the previously believed 25-million-year gap between the Jurassic and Cretaceous periods in Utah, which could clarify many changes in evolutionary history during that time. Greg Ludvigson’s comments underscore the importance of this age determination, providing a more complete understanding of the evolutionary timeline of dinosaurs in the region.
