The Cretaceous Period- 146 to 65 Million Years Ago
Scientists presented strong evidence that the worst cataclysm ever to befall the planet was triggered by a comet that collided with Earth in a spectacular explosion 250 million years ago.
Fireball
The heat of impact sent up a vapor cloud which, within minutes, set the continent aflame. This fireball and the darkness that followed caused global extinction of many plants and animals, including the dinosaurs.
Tyrannosaurus rex
Dinosaurs, went into extinction, ending more than 150 million years of evolution and dominance over life on Earth.

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