Edmontosaurus

edmontosaurus
Edmontosaurus (Wikimedia Commons).

Name:

Edmontosaurus (Greek for "Edmonton lizard"); pronounced ed-MON-toe-SORE-us

Habitat:

Swamps of North America

Historical Period:

Late Cretaceous (70-65 million years ago)

Size and Weight:

About 40 feet long and 3 tons

Diet:

Plants

Distinguishing Characteristics:

Muscular jaws with numerous teeth; duck-like bill

 

About Edmontosaurus

Originally unearthed in Canada (hence its name, honoring the city of Edmonton), Edmontosaurus was a widely distributed plant-eating dinosaur whose strong jaws and numerous teeth could crunch through the toughest conifers and cycads.

With its occasionally bipedal stance and medium height, this three-ton hadrosaur (duck-billed dinosaur) probably ate leaves from the low-lying branches of trees, and also got down on all fours when necessary to browse ground-level vegetation.

The taxonomic history of Edmontosaurus would make for a good-sized novel. The genus itself was formally named in 1917, but various fossil specimens had been making the rounds well before that; as far back as 1871, the famous paleontologist Edward Drinker Cope described this dinosaur as "Trachodon." Over the next few decades, genera like Claosaurus, Hadrosaurus, Thespesius and Anatotitan were thrown around pretty much indiscriminately, some erected to accommodate Edmontosaurus remains and some having new species stuffed under their umbrella. The confusion persists even today; for example, some paleontologists still refer to Anatotitan (the "giant duck"), even though a strong case can be made that this was actually an Edmontosaurus species.

In a stunning feat of retroactive detective work, one paleontologist investigating a bite mark on an Edmontosaurus skeleton determined that it was inflicted by a full-grown Tyrannosaurus Rex. Since the bite was clearly not fatal (there's evidence of bone growth after the wound was incurred), this counts as solid evidence that a) Edmontosaurus was a regular item on T.

Rex's dinner menu, and b) T. Rex did occasionally hunt for its food, rather than contenting itself with scavenging already-dead carcasses.

Recently, paleontologists discovered a partially mummified Edmontosaurus skeleton bearing an unexpected feature: a fleshy, round, rooster-like comb on top of this dinosaur's head. As yet, it's unknown whether all Edmontosaurus individuals possessed this comb, or just one sex, and we can't yet conclude that this was a common feature among other Edmontosaurus-like hadrosaurs.