Iguanodon was one of the first dinosaurs to be found and described. Its remains were discovered in England in the 20s of the nineteenth century. At first, scientists believed that it was a large, heavy animal, moving on four limbs, with a horn at the end of its snout. But after the discovery of several more skeletons, it became obvious that the iguanodon was not as large and massive as was believed.
However, it took time for scientists to come to a consensus about the way the iguanodon moved. Reconstructions depicted an iguanodon standing upright on its hind legs. At the same time, it was believed that the long tail served as an additional support to support the weight of the body, so these reconstructions made the iguanodon look like a huge kangaroo. This opinion existed until the 80s of the twentieth century, when it was found that if the animal really leaned on the tail, it would simply break in half!
Today we learn that the tail of the Iguanodon served as a counterweight and was extended straight back. The spine occupied a position close to horizontal, which means that the iguanodon could move on all four limbs.
This assumption confirms the structure of the front paws: the three middle toes are very strong and end in the likeness of a hoof. The chest bones are also massive and strong. However, the iguanodon could easily move on its hind legs alone.
The so-called nasal horn is not actually located on the nose, but is a spike on the big toe that sticks out and was a fairly effective weapon against predators.
Iguanodon was a herbivore, its jaws and teeth were well adapted to this kind of food. Iguanodon plucked plants with a wide beak, and parallel rows of teeth located on its jaws formed a wide surface for grinding food.
When the jaws closed, the upper and lower teeth touched, and special articulation in the skull allowed the upper jaw to slide sideways while the lower teeth remained in place. Such a device of the jaw apparatus and the flexible structure of the skull were necessary for thorough grinding of food. Iguanodon also had fleshy cheek pouches that trap bits of food and return them to the teeth for further processing