Edmontosaurus
A large duck-billed dinosaur from the end of the Cretaceous.
Edmontosaurus (ed-MON-tə-SOR-əs) is a genus of hadrosaurid (duck-billed) dinosaur whose fossils have been found in western North America. It lived during the late Campanian and Maastrichtian ages of the Cretaceous period, approximately 73 to 66 million years ago, and was one of the last non-avian dinosaurs to exist before the Cretaceous–Paleogene extinction event. The genus includes two known species: Edmontosaurus regalis and Edmontosaurus annectens.
- scientific_name
- Edmontosaurus
- meaning
- lizard from Edmonton
- time_period
- Late Cretaceous (Campanian to Maastrichtian)
- length
- up to 15 meters (49 ft) in exceptionally large specimens
- mass
- up to 15.9 metric tons (17.5 short tons) in exceptionally large specimens
- diet
- herbivore
- locomotion
- bipedal and quadrupedal
Lore & Background
The first fossils named Edmontosaurus were discovered in southern Alberta, Canada, in the Horseshoe Canyon Formation. Over decades, Edmontosaurus fossils were classified under various genera including Anatosaurus, Anatotitan, Claosaurus, Thespesius, and Trachodon, reflecting a complex taxonomic history.
Reader's Guide
Edmontosaurus is significant for its abundance and preservation quality, including extensive skin impressions and possible gut contents. It is one of the best-studied hadrosaurids, with fossils found from Colorado to Alaska, suggesting a wide distribution and preference for coastal plains. Bone beds indicate it lived in groups and may have been migratory. reported the first clear detection of original dinosaur organic material—hydroxyproline, a collagen building block—in an Edmontosaurus fossil, refuting the idea that such organic matter must be contamination. This discovery has major implications for the study of dinosaur biochemistry and preservation.
Did You Know?
- Edmontosaurus was one of the last non-avian dinosaurs, living alongside Triceratops, Tyrannosaurus, Ankylosaurus, and Pachycephalosaurus.
- Edmontosaurus fossils have been found from Colorado to the northern slopes of Alaska.
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