Dinosaurs are divided into two orders according to the structure of their pelvis: from an anatomical point of view, the Saurischia resembled lizards while the Ornithischia were similar to flightless birds such as the ostrich. Our Iguanodon is an exclusively herbivorous oviparous ornithischian ornithopod. The classification of Ornithischia is based on their way of life determined by their teeth, the position of their pelvis and their limbs. The seven valid species of the Iguanodon genus are: I. bernissartensis, I. anglicus (ou mantelli), I. atherfieldensis, I. dawsoni, I. fittoni, I. hoggi and I. lakotaensis.

Although it was presented as a biped during the first reconstructions, it would now seem that the Bernissart Iguanodon was most probably a quadruped. In fact, it was necessary to break its tail to install it the wrong way... The position on all fours would have been normal for running and walking, and it would have stood on its hind legs in a defensive position or when grazing. Its skin was probably delicately grainy with small mosaic elements whose size and positioning would have varied according to where they were on the body. In the majority of reconstitutions, the Iguanodon is greenish-brown.

It was a terrestrial animal, though it could well have sought refuge in marshes and swum using its tail like a crocodile in case of danger. The Iguanodon was undoubtedly devoured by the ferocious carnivorous dinosaurs that terrorised the living world at the time! To defend itself, it could have used its thumb spike and its powerful muscular tail.

At the beginning of the Cretaceous, Bernissart must have been a marshy valley surrounded by hills covered in conifers. The valley was undoubtedly filled with enormous ferns, which were probably the Iguanodons main source of food. There must have been moss but very few flowering plants because angiosperms had only just appeared. The subtropical climate was quite hot and humid with alternating dry and rainy seasons. This was the case all over Europe, whose contours were very different from today’s Europe. Our Iguanodons would have lived alongside insects similar to cicadas, thousands of fish, salamander-like amphibians, turtles and crocodiles, but very few mammals: they were in their infancy back then and lived in the shadow of the dinosaurs.