5. Juravenator
At the opposite end of the size spectrum from Argentinosaurus, Juravenator was one of the smallest dinosaurs at only about 2.5 feet in length. One of the ways Jurassic World can top its predecessors is not necessarily in going with the bigger scale creatures, but also the very, very small. When the novels were first written and the films made, Compsognathids were the smallest known dinosaurs. Discoveries over the last twenty years have meant that this is no longer the case. Jurassic World could reflect that with some truly tiny dinosaurs like Juravenator. Initially thought to be a relative of Compsognathus, paleontologists now think that Juravenator is more closely related to the raptors. The one fossil specimen that exists shows an animal with both extensive scales and some simple feathers, so that would be a way to acknowledge the increasing likelihood that many dinosaurs were feathered whilst keeping them mostly scaly (something like the feathery crests the Velociraptors were given for Jurassic Park III). In the novels Procompsognathus dinosaurs were used as the park's waste disposal system, running freely around eating the dung of the bigger dinosaurs. That they had managed to breed and get off the island is the first sign that something is wrong. Although small, they preyed on children, the infirm and elderly. In the film of The Lost World Compsognathus was used to similar effect in one scene, but the films haven't got much use out of little dinosaurs. A small predator and scavenger would, once again, give Jurassic World a little more variety of scale.