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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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A Brief History of Geologic Time
12:08
Geologists have been able to identify crucial episodes in life’s history.
An Illustrated History of Dinosaurs
12:20
Our image of dinosaurs has been constantly changing since naturalists started studying the
When Whales Walked
4:56
We know whales as graceful giants bound to the sea.
Living Fossils' Aren't Really a Thing
5:05
Even the most ancient-looking organisms show us that evolution is always at work.
When The Earth Was Purple
5:37
But imagine a time when the Earth looked a little … purple.
How Did Dinosaurs Get So Huge?
5:42
Creatures as tall as a five-story buildings shook the Earth.
History's Most Powerful Plants
5:20
Fossil fuels are made from the remains of extinct organisms.
The Age of Giant Insects
5:28
Insects and other arthropods weren’t always so small.
The Strange Case of the Buzzsaw Jaws
3:54
A 270-million-year-old sea creature called Helicoprion that once swam the seas.
The Extinction That Never Happened
7:36
Natural history is full of living things that were long thought to have gone extinct only
Dimetrodon: Our Most Unlikely Ancestor
5:21
Take a close look and you might see a little bit of yourself.
The Biggest Thing That Ever Flew
4:27
Today, we’re familiar with two types of flying vertebrates -- birds and bats.
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