Edmontosaurus is your classic hadrosaur, nothing fancy here, except, you know, it’s a massive reptile and it’s a dinosaur.
Meaning of name: ‘Edmonton lizard’
Species: E. regalis and E. annectens.
Classification: Dinosauria, Ornithischia, Ornithopoda, Hadrosauridae, Saurolophinae, Edmontosaurini, Edmontosaurus.
Size: depending on the species, 9m (30ft) long seems to be the general maximum length, but individuals have been found ranging from 12-13m (39-43ft) in length; E. annectens is regarded as the smaller species but recent fossil analysis suggests the species to be just as large as E. regalis.
Weight: 4 metric tonnes (4.4 Imperial tons).
Time: Maastrichtian Stage of the Late Cretaceous.
Location: Alberta (Canada), Wyoming, South and North Dakota (all three USA).
Named by: Lawrence Lambe, in 1917. E. annectens was named by Othniel Charles Marsh in 1892 but as Claosaurus annectens.
When people think of hadrosaurs, more specifically, when they aren’t thinking about those with the odd-looking crests on their heads, they think of Edmontosaurus; which is probably one of the most generic-looking hadrosaurs out there (to the layman, there may as well be no difference between Edmontosaurus, Maiasaura, Tanius and Shantungosaurus).
Edmontosaurus was arguably one of the most abundant herbivores towards the end of the Cretaceous. It was recently found that the crests and features on hadrosaur skulls, more specifically those on Edmontosaur skulls, change drastically as they age, which means that many E. annectens fossils have been found to, in truth, belong to E. regalis. In much the same way, there were once more Edmontosaur species, but with this new information having come to light, it seems that Anatotitan copei, Edmontosaurus saskatchewanensis, Hadrosaurus longiceps and Thespesius edmontoni are all Edmontosaurus regalis.
These animals lived in herds and were possibly migratory. Their biggest threat would have been Tyrannosaurus, which was certainly not afraid to charge at a large herd and single out a lone hadrosaur in the fray; but living in herds lowered the possibility of young being picked off and the chances of smaller predators managing to take one of them down.
Possibly the most famous Edmontosaurus is Dakota, a near-perfectly preserved fossil found in the Hell Creek formation in North Dakota, she will be the topic of the next post.
This has been Edmontosaurus, this has been me; and you’ve been reading Dinosaurs Made Easy.
Image credit: March of the Dinosaurs Wikia