The Carnotaurs seen in the film were much bigger than their real life counterparts. In reality the were smaller than Iguanodon (Aladar’s species), whereas here they are made even larger than some of the biggest dinosaur predators (like Tyrannosaurus). This was presumably done for dramatic effect and wouldn’t be the first time such a change has been made (the Velociraptors from Jurassic Park
are also several times the size of the actual animals).
Throughout the film, all of the Iguanodonts (including Aladar, Neera, Kron and Bruton) are shown running on all four legs. According to modern paleontological theories, however, it is likely they would’ve been able to rear up on their hind legs to run, if they chose.
The raptors in this film are scaly, even though in real life they were covered in feathers. The movie makers knew this, but animating feathers at the time proved too difficult. Only when the movie was almost done did animation software developments allow for feathers to be animated, but by that time it was too late to include them.
In one scene where Zini is trying to wake up Aladar by pulling on his eye, Aladar’s sclera appears black, as the white of his eye had not been rendered. Shortly after, the tail of one of the lemurs clips into his side.
Incorrectly regarded as goofs
Many scenes contain grass. Grass didn’t evolve until the early Cenozoic era, shortly after the dinosaurs died out. However, recent discoveries indicate that grass did, in fact, exist in at least the Cretaceous period. Naturally, according to science at the time of the production, it was still incorrect.
When Aladar goes back to rescue the herd. He exits the cave and its night time but the cuts of the herd before and after its day time.