Just look at that! This sail-backed dinosaur is Ouranosaurus, an ornithopod related to both the thumb-spiked iguanodonts and the duck-billed hadrosaurs.

It might be difficult to imagine having to haul around such an impressive structure on your back, but the spines of ornithischian dinosaurs were stiff and strong thanks to a criss-crossing lattice... ... that supported their vertebrae made out of ossified tendons - literally, tendons that turned into bone!

Why the long face? Even though it isn't quite a hadrosaur, Ouranosaurus has a remarkably long, hadrosaur-like face. The beak and snazzy little crest really complete the rest of the look!

I wouldn't get too close. Just like it's iguanodontian cousins, the thumbs of Ouranosaurus sport a sharp, conical claw. When they're feeling feisty, they come out swinging like a boxer!