World’s Most Armored Dinosaur
It was the world’s most armored dinosaur, until evolutiondid something strange.
Fossils found in Morocco have revealed that the armoredbody of Spicomellus was also covered in bone spikes that reached nearly a meterin length. The preserved remains are dated to more than 165 million years ago.They also show that the animal lost some of its armor as it evolved.
Spicomellus had a multitude of plates and spikes all overits body. These included meter-long neck spikes, huge spikes projecting upwardsover the hips, and a range of long, blade-like spikes.
Spicomellus was a type of ankylosaur, which were heavilyarmored herbivores with bony skins similar to turtles. They lived from theMiddle Jurassic to the Late Cretaceous period but went extinct 66 million yearsago when a comet wiped out most dinosaurs.
Sometimes described as ‘walking coffee tables’, ankylosaurswere four-legged, squat and under 10 feet in length.
Usually, species become better at defending themselves overtime. But this discovery showed that ankylosaurs lost some of their protection,despite their environment being more dangerous in the Cretaceous period. Thisparticular fossil is the oldest known ankylosaur. Scientists thought that laterspecies might have inherited similar features, but they didn’t. Therefore,experts believe the fearsome variety of spikes may have actually been used forattracting mates and showing off to rivals rather than for defense.
In later species, the spikes are gone, having been replacedby flat plates, which were likely used only for defense. The scientistsspeculate that as larger and more fearsome predators evolved, ankylosaur armorbecame simpler, less showy, and more defensive. This suggests they wanted todraw less attention to themselves.
The end of Spicomellus’ tail hasn’t been found, but some ofthe vertebrae have been fused together, which suggests it had a club or similartail weapon.
