STEGOSAURUS: PLATED GIANT OF THE JURASSIC

Few dinosaurs are as instantly recognizable as Stegosaurus, with its double row of towering bony plates and spiked tail. This herbivore, whose name means “roofed lizard,” roamed western North America about 155–150 million years ago during the Late Jurassic. 

Fossils of Stegosaurus have been found primarily in the Morrison Formation, a magnificent rock unit famous for preserving one of the most diverse dinosaur ecosystems ever discovered.

Stegosaurus could reach up to 9 meters (30 feet) in length but had a disproportionately small head with a brain roughly the size of a walnut. 

Despite this, it thrived as a low-browser, feeding on ferns, cycads, and other ground-level plants using its beak-like mouth and peg-shaped teeth. Its most iconic features were the dermal plates, some nearly a meter tall, running down its back. Their function remains debated—some have proposed they were used for display, species recognition, or thermoregulation.

At the end of its tail, Stegosaurus bore four long spikes, known as the thagomizer. Evidence from fossilized injuries on predator bones suggests these were formidable weapons, capable of piercing the flesh of even the largest carnivores.

Stegosaurus did not live in isolation. It shared its world with a cast of iconic dinosaurs and other ancient animals:

• Sauropods such as Apatosaurus, Diplodocus, and Brachiosaurus dominated the floodplains, their long necks sweeping across the tree canopy.
• Predators like Allosaurus and Ceratosaurus stalked the ecosystem, preying on herbivores. The spikes of Stegosaurus would have been a key defense against these hunters.
• Ornithopods, including Camptosaurus and Dryosaurus, grazed alongside Stegosaurus, representing smaller, quicker plant-eaters.
• Early mammals, small and shrew-like, scurried through the underbrush, while flying pterosaurs soared overhead.
• Freshwater systems hosted fish, turtles, and crocodile relatives, rounding out the ecosystem.

Interesting Facts

• The brain-to-body ratio of Stegosaurus is one of the smallest of any dinosaur, fueling the myth that it had a “second brain” in its hips—an idea no longer supported by science.
• Tracks attributed to stegosaurs suggest they may have moved in small groups, possibly for protection.
• Despite its fearsome appearance, Stegosaurus was strictly an herbivore. Its teeth were too weak to chew tough vegetation, meaning it likely swallowed food in large chunks.
• And, being one of my best loved dinosaurs, I chose Stegosaurus as one of my logos for the Fossil Huntress. This gentle giant is one of my all time favourites!

Stegosaurus lived tens of millions of years before the rise of dinosaurs like Tyrannosaurus rex, and remains one of the most beloved prehistoric creatures. Its strange mix of delicate feeding adaptations and heavy defensive weaponry highlights the balance of survival in the Jurassic ecosystem.

For those that love paleo art, check out the work of Daniel Eskridge (shared with permission here) to see more of his work and purchase some to bring into your world by visiting:https://daniel-eskridge.pixels.com/