The Iguanodon was a dinosaur that could measure up to 16 feet tall, 32 feet long and weigh over 4 tons. It had a horny beak, ideal for pulling vegetation, and moved as well on 2 as on 4 legs. Distinctive features include large thumb spikes, which were possibly used for defense against predators, combined with long prehensile fifth fingers able to forage for food.
