Sound effects
Considering nobody knew what dinosaurs really sounded like, sound designer Gary Rydstrom had a lot of creative freedom when he was tasked to come up with an appropriate sound profile for each of the beasts.
Gary gave each dinosaur a very distinctive roar, and utilised different animal vocalisations to achieve the desired effect, such as swan hissing and a baby elephant trumpeting.
Other pre-historic creatures got more adult sounds, with the squeaks of the Galimimus stemming from a female horse that is exciting by a male’s presence, and the Velociraptor's bark, which came from two tortoises mating.