Initially, the directors were to use the popular Tyrannosaurus as the film's antagonistic predator but at around the time of production, The Lost World: Jurassic Park (1997) was released, which depicted a somewhat softer, motherly side to the classic dinosaur. Thus, a Carnotaurus was used. However, they still changed the Carnotaurus's size and ferocity to that of a Tyrannosaurus. In real life, Carnoaurus were smaller than Iguanodons.
One original concept for the dialogue in the film would have seen the characters not moving their lips and beaks to talk but rather as voice-overs, similar to Homeward Bound: The Incredible Journey (1993).
The elderly Brachiosaurus named Baylene was initially meant to be a much younger male Brachiosaurus named Sorbus who was described by the makers as a sort of Chris Farley-like character who had a fear of heights and so kept his head close to the ground. The character was revised to become Baylene, who, according to her official background story, was the last of a group of elderly Brachiosaurus.
The plot hole pointed out by some as to why the Herd went to have their babies in the Nesting Grounds but didn't remain there (hence the desert exodus) was explained in the "Essential Guide" of the film: the land in the Nesting Grounds becomes too cold and infertile in the winter, driving the Herd to leave it and return when they begin to breed.
The attraction called Dinosaur (previously called Countdown to Extinction) at Disney's Animal Kingdom Theme Park was originally to be created/opened at the same time as the movie's release as part of the company's "synchronicity" between branches of the WDC, but due to the overwhelming technology development required to begin production, the film's opening was delayed. Even though it was started after the film was in-production, the theme park ride opened first (by almost 18 months) before the movie's release; hence, the ride's name change later.
One creature that was designed but cut from the final film was a Mosasaurus, a large, sea-dwelling reptile that would have been used in a scene where the Herd goes to a river to drink and encounters the Mosasaurus. In some video game versions of Dinosaur (2000), however, the Mosasaurus makes an appearance.
The original Script by Walon Green was green lit and set to go into production under the auspices of Effects Master David Allen, utilizing his patented stop motion animation technique in conjunction with live action scenes of actors playing the lemurs which were designed and to be fabricated by Rick Baker. This version was canceled when word came out that Jurassic Park was using full CGI created creatures.
The pack of Velociraptors that chase the Herd were initially intended to sport small feathers along their necks so that they would resemble a pack of Native Americans attacking covered wagons, but the idea was scrapped when animating the feathers proved to be too challenging.
In Sweden and Denmark, Dinosaur (2000) is not considered a film in the Disney Classic canon, and instead includes the film The Wild (2006) to that list to match up to the same number of films. Both films were released theatrically in Sweden.
The movie originated from Phil Tippett's short film Prehistoric Beast (1985), featuring realistic stop-motion dinosaurs. He suggested the idea of adapting it into a feature film to director Paul Verhoeven. The proposed movie would have similarly been mostly animated via stop-motion and would have been a dark, gritty and violent silent film, very much unlike what the eventual movie became. The story would have involved a Styracosaurus fighting against a Tyrannosaurus, and at least one mammal (called Suri, same as in the finished movie) would have appeared as well, live-acted by a human in a suit. It would have had a dark and sad ending due to the asteroid impact, and none of the dinosaurs were to be anthropomorphised (i.e. no talking). Under Disney, the production of the movie took a drastically different route: the stop-motion was replaced with advanced CGI, the animals talked, the dinosaur species were changed, and it was a much more family-friendly and lighthearted movie. The film's opening scene, which features no talking and involves a Carnotaurus brutally killing a mother Iguanodon, was the only surviving remnant of the movie's originally intended tone.
First Disney Animated Feature Film to be Computer Animated instead of Traditionally Hand Drawn. Starting with Chicken Little (2005) 5 years later, all films in the Animated Feature Film line up would be 3D Animated, with the exceptions of The Princess and the Frog (2009) and Winnie the Pooh (2011)
First Disney Film to use the Orange Disney Logo in a Dark Background, which would generally be used for Live Action Films up until 2006. Only Other Animated Film to use this logo had been Brother Bear (2003).
The trivia item below may give away important plot points.
In one version of the ending, Aladar and Kron were to have a fight near a river of lava and Kron would have drifted off in it; the concept was scrapped, possibly as it would've given the film a PG-13 Rating.