For more than a century, paleontologists have been exploring the Hell Creek Formation in western North America to search for new dinosaurs. These rocks preserve some of the last non-avian dinosaurs before the fifth mass extinction on Earth, including icons like Tyrannosaurus and Triceratops. Now, experts have discovered a new dinosaur species from the Cretaceous layer, a turkey-sized creature initially thought to be a young example of a different dinosaur.

When paleontologist Gregory Funston from the Royal Ontario Museum was contacted about some caenagnathid bones found in Hell Creek, it turned out that the foot belonged to the famous Hell Creek chicken. "Initially, my colleagues and I thought that the bones must have come from a juvenile Anzu because they were smaller than other specimens but larger than the species mentioned in 2001," said Funston. However, when Funston and his co-authors examined microscopic details inside the bones, they found evidence that the foot represented a new species.