Hollywood, take heed. Movies like "Fantasia" and the camp classic "Planet of Dinosaurs" show Stegosaurus duking it out with everyone's favorite bone-crusher, Tyrannosaurus rex. There's just one problem: Those two dinos never crossed paths in real life.
Tyrannosaurus had a fairly short reign that lasted from 68 to 65.5 million years ago. Stegosaurus came and went much, much earlier. The oldest specimens on record are around 155 million years of age — while the youngest were fossilized 150 million years before the present.
So the mighty T. rex actually lived closer to the dawn of mankind than it did to Stegosaurus's heyday.
The Jurassic Period, which lasted from 199.6 million to 145.5 million years ago, was drawing to a close when Stegosaurus roamed Earth. Although its range included Portugal, the beast is mainly known from fossil sites in western North America.
Stegosaurus belonged to a suborder of dinosaurs called — what else? — the stegosaurs.
Found in North America, Europe, Asia and mainland Africa, the stegosaurs walked on four legs and had long, beak-tipped skulls.
But it's the ornaments that really grab your attention. Spikes were a stegosaur mainstay, adorning the tails of every known species. Many of these creatures, like Africa's Kentrosaurus, also rocked big old spikes on the shoulders and lower back.
And where the back spikes came to an end, a much weirder feature took over. Stegosaurus and its kin are characterized by the vertical plates above their spines.