In the book it is the first large dinosaur the kidnapped team spot. It is described as a large Hadrosaur that move in large herds, stampeding whenever they are threatened by a predator such as the Tyrannosaurus Rex. They were said to be a yellow-brown color with dark brown camouflage stripesdown their back, similar to the Iguanodon in The Lost Island. In the Cretacous, Cutter and the team witness an Anatotitan being horribly slaughtered by a Tyrannosaurus Rex.
- The T-Rex attack on a herd of them is possibly a reference to Walking with Dinosaurs and When Dinosaurs Roamed America, as in both of these Anatotitans are attacked by a T-Rex.
- It could be the Huge Hippopotamus.
- Anatotitan is the only hadrosaur the team encounters.
- Anatotitan has recently been discovered to be simply a mature Edmontosaurus.