Board Thread:Movie discussion/@comment-68.97.72.113-20150725153906/@comment-192.249.47.187-20151021170622

Dr. Wu a his team used Tyrannosaurus rex as a genetic template for Indominus rex. DNA fom Carnotaurus, Rugops, Majungasaurus, Giganotosaurus, Velociraptor, and Therizinosarus as well as cuttlefish, an unspecified species of tree frog, and an unknown number of other modern animals (perhaps a viper or a boa constrictor since Indominus rex detect heat signatures).

It is stated in the film that hybrid animals are often unstable. The combination of this and the Indominus rex being complete isolation (also stated in the film to be a cause of abnormal behavior) is likely the cause of its almost psychopathic behavior.

The fact that the Indominus rex killed and ate its sibling can be seen as natural behavior. Majungasaurus is one of the few dinosaur species known to eat members of its own species.