Say it: ed-MON-toe-SORE-us · Name means: “Edmonton lizard”
Key facts about Edmontosaurus
⏳ Lived
73–66 million years ago Late Cretaceous
🌿 Diet
Herbivore (plant-eater)
📏 Length
9–12 m (30–39 ft)
↕️ Height
3–3.5 m (10–11 ft)
⚖️ Weight
3,500–7,000 kg (7,720–15,430 lb)
📍 Found in
North America
🔎 Discovered
1917 by Lawrence Lambe
About Edmontosaurus
Edmontosaurus was a big duck-billed dinosaur that lived in herds. It was one of T. rex's favourite meals!
Edmontosaurus was a large, crestless saurolophine hadrosaurid from the end of the Cretaceous in western North America, ranging from Colorado to Arctic Alaska. Exceptional 'mummy' fossils preserve its skin, beak and hooves, making it one of the best-understood dinosaurs.
Drawn to scale next to a 1.7 m adult and a 12 m school bus.
Did you know?
Edmontosaurus had hundreds of teeth packed in its mouth, and it grew new ones all the time!
Some Edmontosaurus fossils are 'mummies' that still show the shape of its scaly skin.
One Edmontosaurus escaped a bite from a big meat-eater, probably a T. rex, and its tail bones healed afterwards.
Herds of Edmontosaurus even lived in Alaska, where winters were dark and chilly.
Tooth microwear studies suggest Edmontosaurus mostly grazed or browsed on low plants such as horsetails, and its jaws chewed with a grinding, sideways motion rarely seen in reptiles.
An Edmontosaurus skeleton at the Denver Museum of Nature and Science has a healed bite wound on its tail that most researchers attribute to T. rex, evidence that it attacked living prey and not only scavenged.
Mummified specimens from Wyoming preserve scaly skin, remains of the keratin beak, mitten-like padded hands and hoof-like tips on the toes.
Huge bonebeds suggest it lived in large groups; whether herds, including those living in Arctic Alaska, migrated with the seasons or stayed put is still debated.
DinoVerse· Edmontosaurus fact sheet
Ornithopods
🌿 What did it eat?
Food: Conifer needles and twigs, Horsetails, Flowering plants, Seeds and fruits.
Cropped plants with a broad, duck-like beak, then chewed them thoroughly with dental batteries of up to hundreds of teeth, grinding food with a sideways sliding motion of the jaws.
Clues scientists use: dental batteries with grinding surfaces; tooth microwear suggesting low, gritty plants such as horsetails; possible stomach contents of conifer needles, twigs and seeds in a 'mummy'; healed T. rex bite marks on its bones.
Who might have hunted it: Tyrannosaurus rex, Albertosaurus, Daspletosaurus.
🗺️ Where fossils were found
Horseshoe Canyon Formation, Alberta, Canada (North America)
Hell Creek Formation, Montana, USA (North America)
Lance Formation, Wyoming, USA (North America)
Prince Creek Formation, North Slope, Alaska, USA (North America)
Skeleton / museum mount of Edmontosaurus: Edmontosaurus in the Rocky Mountain Dinosaur Resource Center,…
Myth or fact?
✗ Myth: Duck-billed dinosaurs like Edmontosaurus lived in lakes and ate soft water plants.
✓ Fact: Its hoof-like feet, grinding teeth and possible stomach contents of conifer needles and twigs show it was a land animal that ate tough plants.
✗ Myth: Its 'webbed' hands meant it was a swimmer.
✓ Fact: The skin on its hands formed a mitten-like pad for walking, not a paddle.
✏️ Quick quiz
Circle the right answer. Name: ______________________
What kind of mouth did Edmontosaurus have?
A A long snout full of sharp teeth
B A parrot beak
C A duck-like bill with many grinding teeth
D No mouth at all
Which predator is known to have bitten a living Edmontosaurus?
A Tyrannosaurus rex
B Velociraptor
C Spinosaurus
D Allosaurus
What are special Edmontosaurus fossils that show skin called?
A Ghosts
B Statues
C Mummies
D Shadows
Answers: 1–C 2–A 3–C
Sources and picture credits
Natural History Museum London — Edmontosaurus — www.nhm.ac.uk/discover/dino-directory/edmontosaurus.html
Wikipedia — Edmontosaurus — en.wikipedia.org/wiki/Edmontosaurus
DinoVerse · Dinosaur fact sheet
