Edmontosaurus

Edmontosaurus annectens was a large hadrosaurid, or 'duck-billed' dinosaur, that roamed the coastal plains of western North America during the Late Cretaceous period, making it one of the last non-avian dinosaurs to exist before the mass extinction event. Reaching lengths of up to 12 meters (40 feet) and weighing several tons, it was a formidable herbivore characterized by its distinctive broad, flattened snout resembling a duck's bill, which was toothless at the front but packed with hundreds of tightly-packed grinding teeth in the cheeks, known as a dental battery. This adaptation was ideal for processing tough plant material like conifers, cycads, and flowering plants. Edmontosaurus was a facultative biped, capable of walking on all fours to graze but likely running on its powerful hind legs to escape predators like Tyrannosaurus rex. Fossils suggest they lived in large herds, migrating across the landscape. The significance of Edmontosaurus in paleontology is immense, largely due to the discovery of several exceptionally well-preserved 'mummy' specimens. These fossils, such as the famous 'Dakota' specimen, preserve not just bones but also fossilized skin impressions, tendons, and even internal structures. These mummies have provided unprecedented insights into dinosaur anatomy, revealing scaly skin patterns, the presence of a fleshy comb-like frill on its head, and the true bulk and musculature of these animals, revolutionizing our understanding of hadrosaur biology and appearance beyond what skeletons alone can tell us.