Fun Facts About Stegosaurus!

The Stegosaurus was a large, four-legged dinosaur with a long, narrow body and a small head that lived on Earth millions of years ago. The most notable features of the Stegosaurus were the row of bony plates that ran down its back and the spikes on its tail. The Stegosaurus was a herbivore, which means it ate plants for food. It had a small beak and teeth that it used to eat plants and leaves. Although the Stegosaurus was not as fast or agile as some other dinosaurs, its bony plates and spikes helped protect it from predators. 

Who First Discovered Stegosaurus?

The first Stegosaurus was discovered by fossil hunter M.P. Felch in the American state of Colorado in 1876, and then named by a scientist called O C Marsh in 1877. As well as naming the Stegosaurus, Marsh and his team discovered and named almost 500 new species of animals, including dinosaurs like Triceratops,  Brontosaurus, Apatosaurus and Allosaurus. Marsh competed with a rival scientist called Edward Drinker Cope to find the most dinosaurs and people called their competition, the Bone Wars.

What Does The Name 'Stegosaurus' Mean?

The name Stegosaurus means ‘Roof Lizard’ in Greek, from the words ‘Stegos’ meaning ‘Roof’ and ‘Sauros’ meaning ‘Lizard’. But the Stegosaurus didn’t have a roof, did it? You’re right, it didn’t! As the Stegosaurus’s kite-shaped armor plates weren’t attached to the bones of the skeleton they easily separated from the body when a Stegosaurus died, which made it hard to work out how they were arranged. When the scientist O C Marsh first named the Stegosaurus in 1877 he thought the plates were arranged on its back like a turtle’s plates, forming a protective shell or roof. That’s how the Stegosaurus got its name. Marsh later found another Stegosaurus that had been covered in mud which held the plates vertically along its back either side of the spine and he realized he’d made a mistake, but the name stuck.

What Does A Stegosaurus Look Like?

With massive armored plates running down its back, sharp spikes at the end of its tail and a teeny weeny head, the Stegosaurus is one dinosaur that you won’t be able to forget. Plodding around on four legs with its tail in the air and its face pushed near to the ground, the Stegosaurus was the size of a normal school bus. And if it looks like the Stegosaurus was always eating low lying ferns and plants, that's probably because it was! The Stegosaurus had a tiny head, particularly compared to the size of its body, and had to eat a lot of plants to support itself. So, it was helpful that the Stegosaurus’s front legs were actually a lot shorter than its back legs, tilting its head downwards near the ground so it could munch on plants and giving its back a distinctive curve.

How Did Stegosaurus Defend Itself?

Stegosaurus has massive spikes on the side of its tail which it could swing powerfully from side to side to defend itself from predators like Allosaurus and Ceratosaurus. In fact, an Allosaurus fossil has been found with a hole in it the exact size of a Stegosaurus tail spike. That must have hurt! Scientists have found lots of broken and healed spikes on Stegosauruses which they think broke when the Stegosaurus wacked other dinosaurs.

Scientists are not sure whether the plates on Stegosaurus’s back were to help it defend itself from attackers too. They might have helped scare predators off, but they wouldn't have been great as armor because they left the sides of the Stegosaurus exposed, which is why scientists think they probably evolved for different purposes.

What Were Stegosaurus Plates For?

Stegosaurus was easily recognizable because of the two-alternating rows of kite-shaped armored plates called ‘scutes’ that stuck up on either side of its back. There were up to 17 plates in total along the length of Stegosaurus’s back.

The bony plates were embedded in the skin of the Stegosaurus, like an alligator's scales, and weren’t connected to the skeleton. This meant the plates often separated from the fossils of the body after Stegosaurus died, which made it difficult for scientists uncovering Stegosaurus fossils to work out where the plates were positioned and what they were used for. This helps explain the errors which led to Stegosaurus getting its name. 

Stegosaurus’s plates could have done lots of different things. The plates could have been protective armor, but as they only covered the top of Stegosaurus’s back they couldn’t have done a very good job. Scientists have found tiny grooves for blood vessels in the plates and think the plates would have been covered in skin when Stegosaurus was alive, which could also have helped the Stegosaurus cool itself down in the hot temperatures. Most scientists think the main purpose of the plates was display, to help Stegosaurus recognize each other, to show which group of dinosaurs they were from and to attract mates. So, the plates were like colorful feathers on a Parrot, like antlers on a deer, or like the frill on a Triceratops.

How Big Is A Stegosaurus?

The Stegosaurus grew to lengths of 9 meters (30 feet) from the top of its beak to the tip of its tail. That’s about the same size as a normal school bus or two cars parked bumper-to-bumper. That might sound massive today, but back then it was a medium sized dinosaur, dwarfed by even bigger dinosaurs like the Diplodocus.

How Tall Was Stegosaurus?

The Stegosaurus grew to heights of 4.3 meters (14 feet) tall. That’s almost the same height as female giraffes, who can reach 4.8 meters (16 feet) tall and taller than a basketball hoop which is 3 meters (10 feet) off the ground!

Where Did Stegosaurus Live?

Stegosaurus lived mainly in North America in the states of Colorado, Utah, and Wyoming, although a fossilized Stegosaurus skeleton has also been found in Portugal. The land would have been very different from today, a flat, dry environment with a carpet of ferns on the ground and woods of conifer trees. There would have been no flowering plants or grasses anywhere!

When Did Stegosaurus Live?

Stegosaurus lived in a time called the Late Jurassic Period which was 152 - 140 million years ago. At that time in North America the dominant predators were the Allosaurus and the Ceratosaurus and there were a lot of other dinosaurs wandering around like the giant Diplodocus, Camarasaurus and Brachiosaurus. 

How Much Did A Stegosaurus Weigh?

Scientists estimate that an adult Stegosaurus weighed between 1.6 - 7 metric tons (3,500 - 15,500 pounds), which means it weighed somewhere between the size of a small hippopotamus to the size of the largest male elephant, or between 17 - 78 grown-up men.

What Does A Stegosaurus Eat?

The Stegosaurus was a herbivore, which means it ate plants for food. Given how big the Stegosaurus was and how small its head was, it must have been constantly eating to keep that big body full.

As the Stegosaurus walked on 4 feet and had back legs which were almost twice as long as its front legs, its head was angled down towards the ground. Unlike the Diplodocus which had a very long neck, and could reach its head up into the trees to eat leaves, the Stegosaurus had a short neck and would mainly eat plants that grew close to the ground.

The Stegosaurus had a bite force similar to a sheep or a cow, but half the power of a dog, and a lot smaller than other beaked dinosaurs like Triceratops and Parasaurolophus. This means Stegosaurus was able to eat soft plant leaves and moss, chewy ferns and maybe small shrubs, but couldn’t chomp through thicker woody plants. Scientists think that in the late Jurassic period, when the Stegosaurus lived, there may not have been any flowering plants or grasses to eat.

The Stegosaurus also swallowed stones, like crocodiles do today, not because they liked the taste, but because the stones helped break down the plants in the Stegosaurus’s stomach.

Does Stegosaurus Have Teeth?

The Stegosaurus didn’t have any front teeth but instead had a beak to tear leaves off plants. Stegosaurus also had around 78 small leaf-shaped teeth in the cheeks at the back of its jaw. Stegosaurus’s jaw was not very flexible though and only allowed up and down movements, so it couldn’t chew grass like a cow which uses lots of side-to-side movements to grind up its food.

Stegosaurus vs. T-Rex

The Stegosaurus and the T-Rex might have both lived in North America, but they lived over 50 million years apart, so they would never have met each other in real life. The T-Rex lived at the end of a time called the Late Cretaceous Period, which was 90 - 66 million years ago. The Stegosaurus lived a lot earlier in a time called the Late Jurassic Period, which was 152 - 140 million years ago, when the Allosaurus was the main predator.

Even though they would never have met in real life, it’s fun to compare the plant-eating Stegosaurus with everyone’s favorite meat-eating dinosaur, the Tyrannosaurus Rex. The Stegosaurus could reach 9 meters (30 feet) in length, whereas the T-Rex grew up to 12 meters (40 feet) in length from its nose to the tip of its tail, so was a lot longer. The Stegosaurus grew to a height of 4.3 meters (14 feet) from the ground to the top of its armored plates, whereas the T-Rex reached 3.6 meters (12 feet) from the ground to the top of its hips. Both of these dinosaurs are a lot taller than grown-ups, with the average man reaching 1.75 meters (5 feet 9 inches) tall.

How Fast Can A Stegosaurus Run?

The Stegosaurus was a slow moving dinosaur. With front legs that were a lot shorter than its back legs and its head tilted down to the ground, the Stegosaurus was not developed to move quickly. 

Is Stegosaurus Intelligent?

Compared with its bulky body, the Stegosaurus had a very small head and its brain was around the size of a plum! When scientists examine the fossilized skull of a dinosaur, they can see from the dinosaur’s brain cavity how big their brain was and whether they had particularly developed senses, like sight or smell. These kinds of traits are more important for predators to hunt their prey. The Stegosaurus’s brain was so small that scientists once thought it had a second brain near its hips, that controlled the back of its body. Actually Stegosaurus only had one small brain. How could such a small brain manage such a big body? Scientists think this means complex behaviors were unlikely and the Stegosaurus was programmed to just eat.

Stegosaurus Coloring Pages

Sources

https://www.nps.gov/dino/learn/nature/stegosaurus-ungulates.htm

https://www.nhm.ac.uk/discover/dino-directory/stegosaurus.html

https://www.amnh.org/exhibitions/permanent/ornithischian-dinosaurs/stegosaurus

https://nhmu.utah.edu/stegosaurus-armatus

https://www.britannica.com/animal/Stegosaurus

https://www.nhm.ac.uk/discover/news/2016/may/dinosaur-eating-habit-insights-stegosaurus-stenops.html

https://www.fossilera.com/pages/dinosaur-teeth

https://www.nhm.ac.uk/discover/stegosaurus-interview-dinosaur-expert.html

https://www.livescience.com/24184-stegosaurus-facts.html

https://www.sciencefocus.com/nature/stegosaurus