One of the icons of the dinosaur world, this is one of those that is instantly recognisable.
Meaning of name: Roof lizard.
Size: 8-9 meters (26-29 feet) long.
Species: Stegosaurus armatus and Stegosaurus stenops.
Classifications: Thyreophora, Stegosauria.
Time period: Kimmeridgian and Tithonian stages (Upper Jurassic).
Named by: Othniel C. Marsh in 1877.
Once upon a time we thought that the plates on this creature’s spine were paired (one next to another in sets of two), we now theorise that the plates were placed in an alternating double row. Back when it was first discovered, though, there were those who thought that the plates were placed flat on the back, jutting out to the sides.
In comparison to it’s total weight (6800 pounds, or 3100 kilograms), Stegosaurus has the smallest brain of any dinosaur; but evidently that tiny brain was enough for this animal as it survived just fine until the end of the Jurassic.
The true use of the plates on a Stegosaurus’ back is unknown, the plates may have been covered in keratin and used for defence (as a form of armour) or they may have simply been covered in skin and used for temperature control. There is evidence to suggest that the latter of the two possibilities was true, as the plates have many vein-like openings and cavities that blood vessels could once have fed through, allowing the animal to quickly cool down on a hot day or warm up on a cold morning. The spikes on it’s tail, on the other hand, were definitely used defensively. It is thought that a swipe from a stegosaur’s tail could easily break an allosaur’s leg or cause serious bleeding at the least.
This was Stegosaurus, this has been me, and you’ve been reading Dinosaurs Made Easy.