This giant browser herbivore, from the family of duck-billed dinosaurs (hadrosauridae), once roamed the coastal plains along the western interior seaway in large herds. Their fossil skeletons are found sometimes numbering hundreds of individuals in one locality. These bone-bed deposits can be found from Canada to Colorado, and provide evidence that Edmontosaurus lived in groups and possibly even migrated. This is also one of the dinosaur species found by researchers to have evidence of Cancer in it's fossil bones, making them an important group for further study. One of the last non-avian dinosaurs on earth, these were dominant land animals at the time of the great extinction event at the end of the Cretaceous period.