The film's character designer David Krentz said, 'Although the production veered away from being very realistic, the animation still plays independently. In its final version, the movie has a narration and goes inside the heads of the animals, so you can hear what they're thinking.' Executives at 20th Century Fox, one of the film's main distributors, viewed a rough cut and thought the film needed voiceovers so children in the audience could connect to the characters.
You can turn the soundtrack off and still get involved with the story and feel the emotions of the characters. He said, 'I think originally, we were looking at a film that could stand alone as a virtual silent movie. Director Barry Cook said the original plan was for the film to be without dialogue or narration. In the film, actors provide voiceovers for the main creatures.