8-4 Death Of The Dinosaurs

Narrator: It is one of the greatest untold stories in the history of life on Earth. From floods to fire, famine to fratricide, one punishment after the next will rain down on our planet, the ultimate precursor to the biblical plagues.

And as in the book of Exodus, the ruling class will be cut down, freeing the lowly mammals, once their vulnerable prey, to forge a dynasty of their own. Now, you will experience the harrowing final year of the dinosaurs. Panic in the sky on Animal Armageddon. Animal Armageddon.

This world ever was and is and shall be ever-living fire. Heraclitus, 6th century BC.

65 million years ago, a world was destroyed when a six-mile-wide asteroid struck the coast of Mexico's Yucatan Peninsula. 100 million megatons of energy were released, shaking the entire planet, sending mega-tsunamis crashing across coastlines and pummeling the surface with falling debris. And that was just the first 24 hours.

Peter D. Ward: We didn't kill everybody off on the first day, but we sowed the seeds that would kill them off. It was as if nature planted a minefield. For every day in the next year, some more of you are going to walk on this mine and get killed off by the killers, which would have been heat, acid rain, darkness, starvation, disease, you name it.

Narrator: The next 12 months would see the fall of one dynasty and the surprising rise of another. Day one has passed, but the final destruction of 150 million years of dinosaur rule over the Earth has barely begun.

Extinction clock, plus two days. From space, Earth looks like an alien planet with rings of debris that will linger for years. Not a single corner of the globe has been spared. Red-hot meteor fragments thrown into space by the impact rain down from the sky. They start fires wherever they hit. The land is trapped in a raging, unstoppable, all-consuming inferno.

Matthew Wedel: Everything would be on fire. Fires would be starting up all over the place. The entire world would be going up in a conflagration, and so the animals have no safe place to go. The herds would be split up and confused. They wouldn't have a safe place to run. They'd be blinded by smoke. Many of them probably died from smoke inhalation as well as from the heat or from the fire outright.

Narrator: High oxygen levels in the prehistoric air make the fires burn even hotter and faster than they would today. Surface temperatures spike. Some places may have reached 1,200 degrees. Untold numbers of dinosaurs are burned alive. North and South America are hit hardest, with fires so intense they are whipped into giant storms of smoke and flame.

Peter D. Ward: Fires create their own problems. They create winds because you've got hot here and cool here. All that cool air is going to rush into that fire, and you start getting these winds themselves that are sucking air into that fire. And fairly soon, the entire continent, as far as we can tell, is on fire.

Narrator: But even in these killing fields, there are a few survivors. In what is now Alaska, our humble ancestor, the small mammal Purgatorius, scrambles for shelter in the raging firestorm. This small creature is a proto-primate, believed to be a precursor to today's primates.

On the outside, it looks like a small rodent, but its teeth are shaped much more like our own than those of a mouse or rat, leading scientists to believe that Purgatorius helped give rise to modern primates. Everything from monkeys to gorillas and even human beings.

Greg Wilson: It probably scurried about, maybe had some climbing ability, but it wasn't a primate that we think of today.

Narrator: For millions of years, Purgatorius has been nothing but a food source for bigger, more powerful dinosaurs.