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When Dinosaurs Roamed America (shortened to When Dinosaurs Roamed outside of the U.S.) is a two-hour American television program (produced in the style of a traditional nature documentary) that first aired on Discovery Channel in 2001. It was directed by Pierre de Lespinois and narrated by actor John Goodman. The featured dinosaurs were designed by Paleo-artist and art director Mark Dubeau, noted for creating dinosaurs for many other Discovery Channel and National Geographic specials. The dinosaur animation was accomplished by animator Don Waller at Meteor Studios, in Montreal, Canada. The music was composed by Christopher Franke (ex-member from Tangerine Dream).

When Dinosaurs Roamed America premiered to 5 million viewers.


Late Triassic segment (New York, 220 million years ago)


  1. Coelophysis
  2. Rutiodon
  3. Desmatosuchus
  4. Icarosaurus
  5. Traversodon
  6. Unidentified Mammal (live-acted by an Eastern Quoll)
  7. Locust

The program starts in the Late Triassic, in New York City. The narrator explains how the Permian mass extinction led to new forms of life, including, eventually, the most extraordinary creatures ever to walk the planet, the dinosaurs. The camera tracks a Coelophysis through the woods. The program depicts Coelophysis as preying mainly on small animals, such as insects and Icarosaurus. It encounters other, larger non-dinosaurian archosaurs such as Rutiodon and Desmatosuchus. The quick Coelophysis is portrayed as a very successful inhabitant of this world.

Early Jurassic segment (Pennsylvania, 200 million years ago)


  1. Megapnosaurus (Identified as its synonym Syntarsus)
  2. Anchisaurus
  3. Dilophosaurus

The program moves on to the Early Jurassic of Pennsylvania, showing a pack of Syntarsus. These dinosaurs, closely related to Coelophysis, are hunting the primitive herbivorous dinosaur Anchisaurus, only to be driven away by a Dilophosaurus, which kills the Anchisaurus to feed its young. The narrator then explains Syntarsus and Dilophosaurus will become the gigantic carnivores such as Allosaurus and T. rex, while Anchisaurus will become the sauropods.

Late Jurassic segment (Utah, 150 million years ago)


  1. Ceratosaurus
  2. Allosaurus
  3. Apatosaurus
  4. Dryosaurus
  5. Stegosaurus
  6. Camarasaurus
  7. Unidentified Pterosaur

The show skips to prehistoric Utah during the Late Jurassic period. The region has been engulfed by a severe drought as the seasonal rain has failed to arrive. A predatory Ceratosaurus stalks a mother and two young Dryosaurus. The predator eventually breaks its cover and charges after the small dinosaurs as they scatter. The Dryosaurus can only flee but the Ceratosaurus is quick too and catches up, grabbing and killing one of the juveniles. The Ceratosaurus feasts while the others escape into a grove of pine trees and run into a herd of sauropods called Camarasaurus. They will be safe around the gentle giants. A male Stegosaurus fights off the attacking Ceratosaurus, the same individual from the earlier sequence, later on using his spiked tail and follows a female Stegosaurus constantly displaying his plates. Eventually, the female decides that he is a healthy individual and the two mate. With the onset of the rainy season, a herd of Apatosaurus arrive, followed by an Allosaurus who launches an assault against the herd while the sauropods graze but is unsuccessful due to their size and strength. The Allosaurus subsequently kills the Ceratosaurus that attacked the Dryosaurus and finally is able to feed. Later whilst following its herdmates, one Apatosaurus stumbles over a fallen tree and tumbles off of a 20 foot high cliff. The sauropod is mortally wounded with a broken leg, and its agonized bellowing is picked up by a pack of hungry Allosaurus. When the Allosaurus arrive, they begin to eat the sauropod alive.

Mid Cretaceous segment (New Mexico, 90 million years ago)


  1. Dromaeosaurus (identified as a Dromaeosaur & raptor most likley suskityrannus fossil 2)
  2. Nothronychus
  3. Zuniceratops
  4. Coelurosaur (suskityrannus specimen 1)

The program then shows a forest located in New Mexico during the Middle Cretaceous period. Small predatory coelurosaurs scamper through the foliage and steal pieces of meat from a dead Zuniceratops. This smaller cousin of Triceratops had been killed by raptors and the hungry dinosaurs are feasting. The raptors chase off a lone Dromaeosaurus as it tries to steal some meat. The lone Dromaeosaurus then tries to attack a grazing Nothronychus, only to be slashed by its long claws and knocked over. Uninjured, the raptor retreats. An old male Zuniceratops is battling for dominance with a younger but healthier male whilst the herd members look on. The younger dinosaur gores the older herd leader in the frill with its right horn, wounding it. The sounds of battle are picked up by raptors and the hungry creatures follow the sounds to a clearing and watch from the foliage as the battle plays out before attacking.

The injured horned dinosaur is attacked by the pack of Dromaeosaurus and is fatally wounded. Another Zuniceratops headbutts the raptor and tosses it off the struggling male. The dromaeosaurs retreat but the old Zuniceratops will not last long. Weeks later, a thunderstorm blows in and lightning illuminates the darkened skies. Panicked dinosaurs scatter but the old Zuniceratops cannot get up. As it sounds its distress call, the Dromaeosaurus return and surround the wounded dinosaur. The raptors attack and soon kill it. Meanwhile, lightning ignites the dry vegetation. Fire springs up, and most of the dinosaurs scatter in all directions. Zuniceratops panic for safety and the Nothronychus follows. However, the feasting raptors are too distracted by eating and fire surrounds the region. The raptors burn to death along with their prey. But some raptors do flee and make it to safety along with some of the other creatures.

Late Cretaceous segment (South Dakota, 65 million years ago)


  1. Tyrannosaurus rex
  2. Triceratops
  3. Ornithomimus (not identified, revealed on website)
  4. Edmontosaurus (identified as its synonym Anatotitan)
  5. Quetzalcoatlus
  6. Purgatorius (live-acted by opossums)
  7. Turtle (live-acted)
  8. Bird (live-acted)
  9. Spider (live-acted)

The program explains that dinosaurs similar to Zuniceratops evolved into the famous Triceratops. In the Late Cretaceous of South Dakota, Anatotitan and Triceratops browse on a rolling grassland bordered by tropical jungle, while Ornithomimus peck at roots and other plants in the area. Flying pterosaurs such as Quetzalcoatlus soar overhead, looking for carcasses. A young Tyrannosaurus arrives on the scene, and the Triceratops form a defensive circle around the juveniles and display their powerful horns whilst the young Tyrannosaurus attempts to get through and roars repeatedly but the horned creatures stay to fight instead of fleeing. Unable to get past the horns of the defensive Triceratops, the T. rex attacks a Quetzalcoatlus, but the pterosaur launches off and flies away from the hungry theropod. The T. rex goes back into the trees and the Triceratops become less agitated. At night, the young Tyrannosaurus returns to its parents. His sister starts to playfully fight with him, but she accidentally hits the mother in the leg with her tail, causing her to roar loudly, waking some bats up in the process. The next day, the young Tyrannosaurus and its family are hunting. They target a herd of Anatotitan grazing in a forest clearing and after bursting from the trees, the herd scatters and flees, the boy and sister T. rexes chase after one individual and it runs straight into the forest where the mother emerges from the bushes, and, grabbing it, kills the hadrosaur by breaking its neck. The mother Tyrannosaurus roars before they feast.

Before they can eat, a huge asteroid, 6 miles across, hurtles towards the planet at 45000 miles an hour and as it enters the atmosphere friction turns it into a blazing missile. The asteroid crosses the ocean in just 4 minutes, crashing into the Gulf of Mexico. The impact gouges out a crater 120 miles wide and sends an incandescent plume of dust, glass and ash into the atmosphere which falls back to earth as fiery debris. The blast wave radiates outward from the impact in a circle and in minutes, everything for hundreds of miles is incinerated by the intense heat or blown apart by the blast wave. Dinosaurs in the region are vaporized in a matter of minutes.

In South Dakota, plants and animals suffer a different fate. Some are incinerated by the mounting heat whilst others succumb to shock waves generated by the collision. Fleeing Triceratops and Anatotitan are caught by the speeding ejecta cloud and destroyed. The feasting Tyrannosaurs watch in horror as a burning blast wave hurtles towards them and flee as pieces of fiery rock rain down. Eventually, all the region's dinosaurs die including the Tyrannosaurus family. A few hours after impact, a heavy cloud of dust and ash settles over America, and temperatures drop as sunlight and heat can no longer reach the surface of the planet. Gasses such as nitrogen and carbon dioxide are burned by the heat and are washed out of the atmosphere as acid rain.

Two months after impact, the sun finally reaches the surface as the heavy cloud of ash clears away. The disaster is over, but 90% of all leaf bearing trees, ferns, vines and plants have been obliterated, and 70% of the animals have died out. Most dinosaurs are extinct.

Despite the depressing and traumatic event, life is described as being resilient, and a turtle is shown emerging from the water and a bird flies overhead, explained by the narrator as the only dinosaurs left. Out of the ashes and charred debris, several small possum-like mammals (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".

Awards and nominations

Primetime Emmy Awards

  1. 2002 - Outstanding Sound Editing for Non-Fiction Programming (Single or Multi-Camera) (Won).
  2. 2002 - Outstanding Outstanding Animated Program (For Programming One Hour or More) (Nominated).
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