Thescelosaurines were a group of small to medium-sized, plant-eating dinosaurs that inhabited North America during the Late Cretaceous epoch. The newly-discovered thescelosaurine species Fona herzogae shows evidence that these dinosaurs spent at least part of their time in underground burrows. Fona herzogae. Image credit: Jorge Gonzalez. Fona herzogae lived approximately 99 million years ago (Cretaceous period) in what is now Utah. At that time, the...