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Season 1 Episode 20 | 5m 37s
More than 4 billion years ago, the crust of the Earth was still cooling and the oceans were only beginning to form. But in recent years, we’ve started to discover that, even in this hellish environment, life found a way.
Aired: 02/15/18
Video has closed captioning.
The Two People We're All Related To
Two humans managed to pass on a very small fraction of their genomes to all of us.
Your Place in the Primate Family Tree
How did we get from a mouse-sized creature that looked more like a squirrel to you?
Scientists have been working for decades to unlock the genetic secrets of the past.
Is LH PV18 a Tarbosaurus bataar? Or a different theropod named Raptorex kriegsteini?
Human ancestors were already walking 3.6 million years ago. But who was first to walk?
Life, Sex & Death Among the Dire Wolves
Dire wolves were real! Their remains taught us a lot about how they lived.
How a Supervolcano Made the Cenozoic’s Coolest Fossils
Yellowstone contains some of North America's most amazing fossil deposits.
How Horses Took Over North America (Twice)
Horses vanished from North America for 10,000 years until a mammal brought them back.
420 million years ago, some fish wore armor – and it may have served a surprising purpose.
That Time Oxygen Almost Killed Everything
What if we told you that there was a time when oxygen almost wiped out all life on Earth?
How Two Microbes Changed History
More than two billion years ago, a tiny living thing started to live inside another thing.
The Other Explosion You Should Know About
The Sudden burst of diversity that marked the dawn of truly complex life on our planet.
What Was the Ancestor of Everything?
The search for our origins go back to a single common ancestor.
Where did viruses come from and how did they evolve? Are viruses alive?
