Iguanodon

Iguanodon (meaning “iguana tooth”) is a genus of the ornithopods. It is currently assumed to stand on its hindlimbs, and yet normally walk on all fours. If attacked, it could dissuade a predator with its powerful thumb spike.

Iguanodon has become quite famous as a result of its starring role in the Disney animated film Dinosaur, but before that it helped people understand what dinosaurs really looked like. Iguanodon was one of the first dinosaurs discovered, and this allowed scientists who had never seen a complete dinosaur, to figure out what it would have looked like in life. In fact, the first time this common dinosaur was found as just a partial skeleton, scientists put its thumb spike on its nose thinking it was a horn.

This was only the second dinosaur to be described, after Megalosaurus. Its teeth were discovered in the early 1820s in England – these original fossils were “rediscovered” in the British Museum in 1977. As nothing like it had ever been described in scientific literature, the teeth of this creature were a puzzle that an amateur paleontologist named Gideon Mantell solved by comparing them to the teeth of living animals. Mantell found that the teeth looked like those of a modern iguana and named it Iguanodon. He speculated that it was a huge extinct version of this modern reptile. It was in 1878 in a coal mine in Belgium that 24 fairly complete and articulated specimens were found. Although they were of a larger species, they clearly showed what this creature looked like in life.