One of the most recognizable dinosaurs, the Stegosaurus, has large plates going from its head to its tail. Not only did this dinosaur have plates, but it also had spikes on its tail. It is through that they used these features to defend themselves. 

The tail and spikes are used like a club to attack enemies. They’ve even found spike-shaped wounds in fossils of their predators. These famously armored dinosaurs had to protect themselves because they couldn’t outrun their predators.

Stegosaurus Quick Facts

How Was It Discovered?

The first fossil of a Stegosaurus was discovered in Colorado by Arthur Lakes in 1877. However, it wasn’t until 1885 that Marshall. P. Felch. Found one of the most complete Stegosaurus skeletons. 

Stegosaurus didn’t get its name until 1877, when the paleontologist Othniel Charles Marsh was brought to the mostly complete skeleton to dig up. This was actually during a time known as the Great Dinosaur Rush, where O. C. Marsh and Edward Drinking Cope were competing on fossil hunts. 

Where Did Stegosaurus Live?

The stegosaurus has been found in both the western United States and in Portugal. 

Their fossils have been found in:

• Colorado
• Wyoming
• Utah
• Portugal
• Spain

The land masses of the US and European landmasses used to be connected millions of years ago. Thus, fossils were found in the US as well as Portugal and Spain.

What Did Stegosaurus Eat?

The Stegosaurus was a plant-eating dinosaur, called a herbivore.

Having a downward tilting posture and a low-hanging head, they would have eaten low plants such as:

• ferns
• Horsetails
• Cycads
• Conifers
• various mosses

Let’s look at the main physical features of this dinosaur…

Stegosaurus Skull, Teeth, and Plates

These four-legged dinosaurs had shorter front legs and a very small head, leading to a forward tipping posture.

Stegosaurus had a small skull, only 16 inches long, with a tiny brain about the size of a walnut. Their teeth were small and peg-shaped, perfect for shredding vegetation. 

Known for their back plates, these massive dinosaurs had plates running from their head to their tail. The largest of the plats could be up to 3 square feet. 

How Big Was It?

This huge herbivore looks even bigger because of its back plates.

Stegosaurus was huge:

• 30 feet (9.1 meters) long
• 13 feet (4 meters) tall
• Had backplates up to 3 feet tall
• Weighed up to 4.5 tons

Next, let’s look at how strong their senses were.

Stegosaurus’ Senses

Stegosaurus was a herbivore and thus was often prey for other carnivores. It used its sight, smell, and hearing to be aware of other dinosaurs around it.

Stegosaurus had:

• Eyes on the sides of its head
• Average sense of smell
• Ear holes optimized for low-frequency sound

Unlike other longer-necked dinosaurs that could reach higher plants or were strong enough to knock over trees and such, the Stegosaurus was stooped low, and thus limited in its diet. 

Additional Facts

• Lived among other dinosaurs: The stegosaurus lived among the following dinosaurs: Apatosaurus, Diplodocus, Camarasaurus, and Allosaurus. The Allosaurus was actually its main predator
• Smallest Brain: The Stegosaurus had the smallest brain of the large dinosaurs, roughly the size of a plum. 
• Tail Spikes: The stegosaurus can have 4-10 spikes on its tail, the collection of which is called a thagomizer. 
• Armored to the Bone: The stegosaurus couldn’t flee its predators because it couldn’t run at all due to its body restrictions. Instead, it had its large plates, tail spikes, and an extremely bony neck to protect itself. 
• What are the Plates for? Scientists are still speculating on the purpose of the plates. Scientists assume that the plates may have been used to scare off predators as well as to regulate body temperature. There is proof that blood vessels could have run through the plates to cool off the stegosaurus. 

Famous Stegosaurus Skeletons

Sophie: a mostly complete Stegosaurus skeleton, 10 feet tall and 20 feet long! This fossil is on display in Europe in the Natural History Museaum in the Earth Hall.

Apex: A 150-million-year-old fossil. This skeleton is on display in the American Museaum of Natural History

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