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Stegosaurus

life science Maturity 7-9 Next article →

Stegosaurus is one of the most famous dinosaurs in the world.

Stegosaurus size comparison
Stegosaurus size comparison

These large, four-legged animals lived during the Late Jurassic period. This was between 155 and 145 million years ago. They were herbivores, which means they only ate plants. Because they had small heads and short necks, they likely ate low bushes and shrubs.

Stegosaurus stenops skull cast - Natural History Museum of Utah - DSC07228
Stegosaurus stenops skull cast - Natural History Museum of Utah - DSC07228

They lived alongside other well-known dinosaurs like Apatosaurus and Diplodocus. Some predators, like Allosaurus, may have hunted them.

Allosaurus attacks Stegosaurus
Allosaurus attacks Stegosaurus

This dinosaur had a very unique way of looking. It had big, kite-shaped plates standing upright along its back.

Stegosaurus plates
Stegosaurus plates

Scientists think these plates were used for display or for thermoregulation. Thermoregulation is a way an animal manages its body heat. The dinosaur also had sharp spikes on its tail. These spikes were used for defense against predators.

Thagomizer (spike)
Thagomizer (spike)

Their bodies were heavily built with rounded backs. They had short front legs and much longer back legs. This meant they held their tails high in the air.

Finding these fossils was part of a famous time called the "Bone Wars."

Othniel Charles Marsh first identified these remains in 1877. He worked at Dinosaur Ridge National Landmark. The first bones found were very broken and scattered. Because of this, it took many years to understand their true shape. Marsh even thought the plates laid flat like roof shingles at first. He named the animal "roofed lizard" because of this idea.

Stego
Stego

Many different types of Stegosaurus have been found.

Stegosaurus ungulatus
Stegosaurus ungulatus

Three species are widely recognized in the western United States. These are Stegosaurus stenops, S. ungulatus, and S. sulcatus. One species, S. ungulatus, was very large. It could weigh over 5,000 kilograms.

Stegosaurus size comparison
Stegosaurus size comparison

Fossils have been discovered in both the United States and Portugal. Over 80 individual animals have been found by researchers. Most of these fossils come from the Morrison Formation. This area is a famous place for finding dinosaur bones.

Today, you can see Stegosaurus in many places.

Stegosaurus ungulatus
Stegosaurus ungulatus

They appear in movies, books, and even on postal stamps. Many museums have large skeletons on display for people to see.

Stegosaurus stenops Life Reconstruction
Stegosaurus stenops Life Reconstruction

Because complete skeletons are rare, museums often make composite displays. This means they use bones from several different animals to make one display. The National Museum of Natural History has a famous mount of S. stenops. You can also find them at the American Museum of Natural History. These displays help us see how these amazing creatures once moved.

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🖼️ Images & Media (18)
File:Stego-marsh-1896-US geological survey.png
Stego-marsh-1896-US geological survey.png
File:Stegosaurus ungulatus skeleton peabody museum 1910.png
Stegosaurus ungulatus skeleton peabody...
File:Stego.jpg
Stego.jpg
File:Stegosaurus size comparison.svg
Stegosaurus size comparison.svg
File:Stegosaurus stenops skull cast - Natural History Museum of Utah - DSC07228.JPG
Stegosaurus stenops skull cast - Natural...
File:Stegosaurus ungulatus.jpg
Stegosaurus ungulatus.jpg
File:Stegosaurus stenops Life Reconstruction.png
Stegosaurus stenops Life Reconstruction.png
File:Stegosaurus ungulatus.png
Stegosaurus ungulatus.png
File:Stegosaurus dorsal plate - Museum of the Rockies - 2013-07-08.jpg
Stegosaurus dorsal plate - Museum of the...
File:HMNS Stegosaurus.jpg
HMNS Stegosaurus.jpg
File:Allosaurus attacks Stegosaurus.jpg
Allosaurus attacks Stegosaurus.jpg
File:Stegosaurus plates.jpg
Stegosaurus plates.jpg

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