 Gallimimus are featured in a stampede scene where one of them is devoured by the Tyrannosaurus . The Gallimimus was the first dinosaur to receive a digital version , being featured in two ILM tests , first as a herd of skeletons and then fully skinned while pursued by the T. rex . Its design was based on ostriches , and to emphasize the birdlike qualities , the animation focused mostly on the herd rather than individual animals . As reference for the dinosaurs ' run , the animators were filmed running at the ILM parking lot , with plastic pipes standing in as the tree that the Gallimimus jump over . The footage even inspired to incorporate an animal falling in its leap as one of the artists crashed making the jump . Horse squeals became the Gallimimus sounds . 
