When Dinosaurs Roamed America

***When Dinosaurs Roamed America*** (sometimes shortened to ***When Dinosaurs Roamed*** outside of the U.S.) is a two-hour American television program produced by Evergreen Films for the Discovery Channel. It follows the reign of the dinosaurs in the United States from their beginnings to their extinction. It was narrated by John Goodman and premiered on July 15, 2001.

The show was one of Discovery's first attempts to replicate the success of *Walking with Dinosaurs*, following a similar style by being produced in the style of a nature documentary and presenting the titular dinosaurs as actual animals in their natural habitat; however, this program followed a different style, being a single special with different segments as opposed to a three-hour miniseries. This show is also notable for being the first form of media to featured feathered dinosaurs.

## Synopsis

### Late Triassic (220 million years ago)

The program starts in the Late Triassic period, near modern-day New York City in the Newark Supergroup. The world has just begun to recover from the effects of the Permian-Triassic extinction event, which has led to new forms of life to appear, including the dinosaurs. The segment follows a Coelophysis as it travels through the woods, preying mainly on small animals like insects and Icarosaurus. It also encounters larger, non-dinosaurian archosaurs like Rutiodon and Desmatosuchus. The Coelophysis is portrayed as quick and a very successful inhabitant of its world.

### Early Jurassic (200 million years ago)

A pack of Syntarsus, dinosaurs closely related to Coelophysis, are hunting in the forests of Pennsylvania. They come across an Anchisaurus, a herbivorous dinosaur, which kills one of the pack members in a failed attack before retreating with the pack in pursuit. The Syntarsus are frightened off by a Dilophosaurus, which then kills the Anchisaurus to feed its offspring and fends off another intruding Dilophosaurus to protect the kill. The Syntarsus later return to scavenge a meal, but the second Dilophosaurus returns and scares them away before feeding on the carcass. The narrator explains that Anchisaurus will eventually evolve into sauropods, whilst Syntarsus and Dilophosaurus will evolve into more gigantic carnivores.

### Late Jurassic (150 million years ago)

The region of Utah has become engulfed in a drought, and rain has failed to arrive. A Dryosaurus and her offspring are digging for water when they are suddenly attacked by a Ceratosaurus, who kills and devours one of the juveniles. The mother and remaining offspring escape. A herd of Camarasaurus feed on the tall pine trees, with the Dryosaurus traveling along for protection. A male Stegosaurus is attempting to attract a resident female when the Ceratosaurus attacks; the male uses his spiked tail to drive the predator away and begins to follow the female, displaying his plates. Soon, the rains arrive, and everything is green again. A herd of Apatosaurus arrives, followed by several Allosaurus. One Allosaurus attempts to launch an attack on the herd but is driven off by their size and strength. The Dryosaurus and her remaining offspring are once again attacked by the Ceratosaurus but escape when their attacker is killed and eaten by a larger Allosaurus. The female Stegosaurus decides that the persistent male is a healthy individual and allows him to mate with her. Having eaten their fill, the Apatosaurus herd moves on in search of fresh food, but one member falls from a broken leg and into a ditch. Its bellows attract a trio of Allosaurus, who proceed to eat the sauropod alive.

### Mid Cretaceous (90 million years ago)

In the forests of New Mexico, herds of Zuniceratops, the first horned dinosaurs to appear in North America, roam, with coelurosaurs scampering around. A pack of raptors feast on a Zuniceratops they have killed. A lone male arrives to steal some meat, but the pack drives him off. The lone dromaeosaur then tries to attack a grazing Nothronychus, but is slashed by its long claws and knocked over, though it escapes unharmed. An old male Zuniceratops battles with a younger male for access to the females and position of leader of the herd. The old male is wounded when his young rival stabs him in the frill with his right horn. The sounds of the fight are picked up by raptors and they watch the battle from the foliage. One of them attacks the wounded male, but another Zuniceratops headbutts the dromaeosaur, sending it flying off the struggling male. The dromaeosaurs retreat, but the old male will not last long. Weeks later, a thunderstorm blows in and lightning spooks the herd, who run off and leave the old male behind. As it sounds its distress call, the dromaeosaurs return joined by a fourth member and kill him. Lightning strikes the dead vegetation, which quickly catches fire. The Zuniceratops and several other creatures flee to safety, with the Nothronychus close behind. But the raptors are too busy eating and are surrounded and die in the fire. However, several other raptors manage to escape with several other creatures.

### Late Cretaceous (65 million years ago)

In South Dakota, Triceratops and Anatotitan graze on a rolling grassland bordered by tropical jungle, while Ornithomimus pecks at roots in the area. Flying pterosaurs such as Quetzalcoatlus soar overhead, looking for carcasses to eat. A young Tyrannosaurus rex arrives on the scene, practicing its skills to hunt alone. The Triceratops form a defensive circle around their juveniles and wave their horns and frills at the predator, who turns its attention to a Quetzalcoatlus feeding on a dead dinosaur. The T. rex charges the pterosaur, but it gets away, and the T. rex goes back into the trees.

At night, the T. rex reunites with its family, and the mother chastises two of her young when one of them hits her scarred leg while sparring. The next day, the mother teaches her young how to hunt. They target a herd of Anatotitan grazing in a forest clearing. The herd senses the pack and flees, with the T. rex singling out one individual that is promptly killed by the mother. As the T. rex begin to feast, an asteroid, six miles across, hurtles towards the planet at 4500 miles per hour and crashes into the Gulf of Mexico. The impact creates a crater 120 miles across and sends a cloud of dust and debris into the sky. The blast wave radiates outward from the impact in a circle and in minutes, everything for hundreds of miles is incinerated by the heat or blown apart by the blast wave. Dinosaurs in the region are vaporized in minutes. The T. rex family are also killed, along with all of the other dinosaurs in South Dakota.

Two months later, the Sun finally reaches the surface as the heavy ash cloud clears away. The disaster is over, but ninety percent of all leaf-baring plants have been obliterated, and seventy percent of the animals, including the dinosaurs, have died out.

Despite the depressing and traumatic event, life is described as resilient, as a turtle emerges from the water and a bird flies overhead, described by the narrator as the only dinosaurs left. Out of the ashes of charred debris, small mammals called Purgatorius emerge, and the narrator explains that small mammals such as these will eventually evolve into humans and think back in awe to a time "when dinosaurs roamed America".

## Broadcast

*When Dinosaurs Roamed America* premiered on the Discovery Channel on July 15, 2001; its premiere served as a tie-in with the release of Universal's *Jurassic Park III* that same week. The show was one of the highest-rated programs in the summer of that year, making a 3.6 household rating on 5 million viewers and boosting that month's cable to a 29.4 average rating.

## Home media

Main article: *When Dinosaurs Roamed America (Home video)*