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When Sharks Swam the Great Plains

When Sharks Swam the Great Plains

Season 2 Episode 5
11:45

When Apes Conquered Europe

Season 2 Episode 6
8:08
When Humans Were Prey

When Humans Were Prey

Season 2 Episode 8
9:21
How Blood Evolved (Many Times)

How Blood Evolved (Many Times)

Season 2 Episode 9
9:56
The Humans That Lived Before Us

The Humans That Lived Before Us

Season 2 Episode 10
11:52
The Island of Shrinking Mammoths

The Island of Shrinking Mammoths

Season 2 Episode 11
11:20
The Giant Bird That Got Lost in Time

The Giant Bird That Got Lost in Time

Season 2 Episode 15
8:33
When We First Made Tools

When We First Made Tools

Season 2 Episode 16
9:08
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Eons

How Sloths Went From the Seas to the Trees

Season 2 Episode 4

The story of sloths is one of astounding ecological variability, with some foraging in the seas, others living underground, and others still hiding from predators in towering cliffs. So why are their only living relatives in the trees?

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The Rise and Fall of the Bone-Crushing Dogs
8:29
What happened to the biggest dogs that ever lived?
Earth & Climate Science
9:15
Yellowstone contains some of North America's most amazing fossil deposits.
How Horses Took Over North America (Twice)
9:08
Horses vanished from North America for 10,000 years until a mammal brought them back.
When Birds Had Teeth
11:29
How did Archaeopteryx relate to today’s birds? Its teeth provide a major clue.
When Fish Wore Armor
9:37
420 million years ago, some fish wore armor – and it may have served a surprising purpose.
The Mystery of the Eocene’s Lethal Lake
7:59
In the 1800s, miners found beautifully preserved fossils of animals from the Eocene.
When Insects First Flew
8:38
Insects were the first animals to fly. Scientists are still working on how it happened.
FAQs From Our First Year
9:20
To celebrate our first anniversary together, we’d like to answer some of your questions.
Dinosaurs
6:54
Tyrannosaurus rex had tiny arms. How did this happen, and why did it keep them?
When Fish First Breathed Air
8:40
Before a group of fish could live on dry land, they acquired the ability to breathe air.
Early Life on Earth
7:29
Where did viruses come from and how did they evolve? Are viruses alive?
Why Triassic Animals Were Just the Weirdest
9:07
Why the Triassic was full of creatures that look a lot like other, more modern species.
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