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How 7,000 Years of Epic Floods Changed the World

How 7,000 Years of Epic Floods Changed the World

Season 2 Episode 13
9:28
The Island of Huge Hamsters and Giant Owls

The Island of Huge Hamsters and Giant Owls

Season 2 Episode 14
11:41
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
Ancient Fauna, Flora & Fungi

When Giant Scorpions Swarmed the Seas

Season 2 Episode 17
11:38
When We Tamed Fire

When We Tamed Fire

Season 2 Episode 18
11:46
The Mystery Behind the Biggest Bears of All Time

The Mystery Behind the Biggest Bears of All Time

Season 2 Episode 19
10:41
The Croc That Ran on Hooves

The Croc That Ran on Hooves

Season 2 Episode 22
8:41
The History of Climate Cycles (and the Woolly Rhino)

The History of Climate Cycles (and the Woolly Rhino)

Season 2 Episode 23
13:14
The Hellacious Lives of the "Hell Pigs"

The Hellacious Lives of the "Hell Pigs"

Season 2 Episode 24
7:17
How Evolution Works (And How We Figured It Out)

How Evolution Works (And How We Figured It Out)

Season 2 Episode 25
12:09
When the Synapsids Struck Back

When the Synapsids Struck Back

Season 2 Episode 26
10:10
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Eons

The Evolution of the Heart (A Love Story)

Season 2 Episode 12

In order to understand where hearts came from, we have to go back to the earliest common ancestor of everything that has a heart. It took hundreds of millions of years, and countless different iterations of the same basic structure to lead to the heart that you have today.
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