The film was the most expensive movie of 2000, costing $130 million United States dollars, although unofficial estimates put it around $200 million. This film was rated PG by the MPAA for intense images.
Pop singer/songwriter Kate Bush reportedly wrote and recorded a song for the film but due to complications the track was ultimately not included on the soundtrack. According to HomeGround, a Kate Bush fanzine, it was scrapped when Disney asked Bush to rewrite the song and Bush refused; however, according to Disney, the song was cut from the film when preview audiences did not respond well to the track. In Asia, pop singer Jacky Cheung's song Something Only Love Can Do, with versions sung in English, Mandarin Chinese and Cantonese, was adopted as the theme song for the film.
The Countdown to Extinction attraction at the Disney's Animal Kingdom theme park was re-named and re-themed to the movie, and is now known as Dinosaur. The storyline was always intended to tie in with the movie, considering the usage of a Carnotaurus as the ride's antagonist and Aladar is the Iguanadon that guests rescued from the meteor shower and take him back into the present, seen wandering the Dino Institute in Security Camera footage seen on monitors in the attraction's unloading area.
Aladar and the four surviving lemurs go in search of a new home and eventually wander into a desert. They are soon attacked by a pack of Velociraptor but are rescued when a multispecies herd of dinosaurs crosses their path, scaring the predators away. The herd is heading for their traditional breeding grounds, believed to have been spared from the meteoroid's blast. Aladar joins the herd, despite Yar's protests, and befriends the elderly Eema (Styracosaurus), Baylene (An elderly Brachiosaurus), and their pet Edmontonia Url. Kron, the leader of the herd is a merciless Iguanodon with a strong belief in a Social Darwinism-like philosophy, wherein only those who can survive on their own power deserve to live. These beliefs are shared by his henchman Bruton. This causes strong tension between Kron and the more compassionate Aladar, which is only complicated by Aladar's instant attraction to Neera, Kron's sister – the first female of his kind that he has ever seen. Aladar and Neera's relationship is initially strained because of Zini's honest but ineffective efforts to help Aladar win her affections.
Later, when the herd arrives at the watering hole that they have relied on for past voyages only to find it empty, Kron orders the herd to move on, despite Neera's protests. Eema, growing weak of thirst, enters the empty lake bed. Aladar and Baylene follow her, and Aladar notices something is out of place about Baylene's footsteps. After digging, they find water trapped beneath the sand. He recalls the herd with a loud cry, and Kron is the first one to arrive, attacking all who try and drink the water before him. Nevertheless, Neera becomes infatuated with Aladar and the two begin to develop a positive bond when he teaches two young orphaned Iguanodons that Neera looks after, and later, Neera, how to get water. Bruton, who had temporarily left the herd along with a scout to search for water in the dry lake bed, returns alone mortally wounded, attacked by a Carnotaur. He warns Kron that there are in fact two Carnotaurs pursuing the herd, (the predators having been driven from their normal hunting grounds by the meteor) and Aladar, the lemurs, and the elderly dinosaurs get left behind as the herd picks up the pace. Bruton is also left behind, unable to keep up due to his injuries. Aladar invites him to stay with the misfits and himself. Bruton at first is reluctant to embrace this new idea and philosophy of helping others, but his loyalty is proved when the predators attack the stragglers inside of a cave. Bruton sacrifices himself to save the others, collapsing the cave onto the Carnotaurs, killing one and severely wounding the other.
The group is trapped in the cave, and Aladar begins to mold into Kron's philosophy of survival-of-the-fittest after Bruton's death and his repeated failures, only to have his friends and family to rescue him from this dark outlook, telling him that Aladar's philosophy for helping others is the reason that they are all alive. With this in mind, the group escapes the cave and eventually finds its own way to the nesting grounds. Once there, they see that the original route to the breeding grounds has been blocked by a landslide, leaving the herd without a way of entry. And even if the herd can manage to climb up the wall of rocks, they would face a sheer drop on the other end and none or only a few will survive. Aladar leaves to tell Kron of the alternate route. On his way, he discovers that the remaining Carnotaurus is close on the trail of the herd. Aladar discovers that the herd is following the leader, Kron, in a perilous attempt to scale the wall into the breeding grounds. Aladar tells them of his discovery, but Kron refuses to listen. Instead he attacks Aladar, furious that his authority has been questioned and challenged. The two fight, until Kron knocks Aladar into a nearby rock. As Kron goes in for the kill, he is knocked down by Neera, who is tired of his cruel beliefs. Neera helps Aladar to his feet. Together Aladar and Neera led the herd away from Kron and towards the exit of the canyon. Stubborn as ever, Kron attempts to climb the wall alone, refusing to submit to the leadership of another.
Suddenly, the surviving Carnotaurus comes round the rocks and corners the herd. The hungry carnivore charges, but is discouraged from a meal by the unity of the group (led by Aladar). Driven back into a corner, once the herd passes, it then spots Kron climbing the wall, and moves to attack him. Neera and Aladar follow to save Kron. Upon reaching the top of the rocks, Kron realises he is now cornered by the predator. Kron charges into battle; however, he is thrown hard against the rocks. Aladar and Neera arrive just as the Carnotaur inflicts a fatal wound to Kron. In the fight that follows, the Carnotaur gains the upper hand, but Aladar knocks it to the edge of a cliff: the ground gives way under the theropod's feet and the Carnotaurus plummets to its death. Neera rushes to Kron's side only to find that it is already too late. Kron is dead. Aladar takes over as the new leader and leads the herd through the cave into the nesting grounds, where the lemurs also find that they are not the last of their kind, and that there are lemurs in the nesting grounds. Zini finally gets a mate, Suri gets new friends and the lemurs have a new tree like the old one. This one has a lake for the lemurs to drink and swim. The movie ends with one of Neera and Aladar's eggs hatching, showing the dinosaurs' peaceful life in the valley. As the film closes, Plio's voice can be heard above the jubilant bellows of nesting mothers, saying, "None of us really know what changes, big or small, lie ahead. One thing is certain; our journey is not over. We can only hope that, in some small way, our time here will be remembered." This seems to be a comment on the idea that, while dinosaurs are extinct, they will never be forgotten, or on the nature of life itself.
| Character | Species | Role | English voice actor | French voice actor | Spanish voice actor | Japanese voice actor |
|---|---|---|---|---|---|---|
| Aladar | Iguanodon | A brave and compassionate Iguanodon who's been adopted into a family of lemurs and does what he can to make sure that the old and weak aren't left behind during the herd's migration. | D.B. Sweeney | Bruno Choël | Mariano Alameda | Yoshihiko Hakamada |
| Plio | Coquerel's Sifaka | A lemur matriarch who cares for her family. | Alfre Woodard | Micky Sébastian | Mercedes Sampietro | Gara Takashima |
| Yar | Coquerel's Sifaka | A lemur patriarch whose occasional gruff demeanor is just a front covering his more compassionate interior. | Ossie Davis | Med Hondo | Pepe Mediavilla | Takeshi Watabe |
| Zini | Coquerel's Sifaka | Aladar's stepbrother and wisecracking sidekick. Suri's older brother and Plio's son. | Max Casella | Jamel Debbouze | Javier Cámara | Ryūsei Nakao |
| Suri | Coquerel's Sifaka | Aladar's stepsister, Zini's little sister and Plio's daughter. | Hayden Panettiere | Marie Sambourg | Paula Ribó | Yumi Sudō |
| Kron | Iguanodon | The fascist ruler of the herd who doesn't care for the weak dinosaurs in his herd. He believes in survival of the fittest. | Samuel E. Wright | Richard Darbois | Alfonso Vallés | George Nakata |
| Neera | Iguanodon | Kron's sister, who ends up falling in love with Aladar because of his compassionate ways. | Julianna Margulies | Ninou Fratellini | Maribel Verdú | Makiko Esumi |
| Bruton | Iguanodon | Kron's domineering right-hand assistant. He died in a fight with the Carnotaurs, although he killed one. | Peter Siragusa | Marc Alfos | Joan Crosas | Tesshō Genda |
| Baylene | Brachiosaurus | An elderly and dainty Brachiosaurus. | Joan Plowright | Lily Baron | Marta Martorell | Miyako Shima |
| Eema | Styracosaurus | A wizened, young and slow-moving Styracosaurus, owner of Url. | Della Reese | Perrette Pradier | Enriqueta Linares | Masako Isobe |
Many of the animals in the film also bore anatomical inaccuracies. For example, there is strong evidence to suggest that both Oviraptor and Velociraptor had plumage. In fact, the initial designs depicted the Velociraptor and Oviraptor with feathers. However, due to time, technical, and budget restrictions, they ended up featherless. The animators also found it too difficult to animate beaks as mouths, and decided to give the Iguanodon lips, turning their beaks into teeth. The Iguanodon were also shown galloping when they ran; this would have been very difficult to do, as their spine was very inflexible vertically. Several dinosaurs, including Styracosaurus and Carnotaurus, were not as large as the film depicted. The Carnotaurus were resized for entertainment's sake, being closer in size to larger theropods like Tyrannosaurus. In reality, they were smaller than Iguanodon (and half their weight), and less bulky than depicted in the film. Longisquama could not fly as it did in the film, though some have suggested it could glide or parachute from trees. Also, grass evolved after the Mesozoic Era, unlike in the movie.