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Season 1 Episode 38 | 8m 5s
The ancestors of modern, squishy cephalopods like the octopus and the squid all had shells. In ancient times, their shell was their greatest asset but it eventually proved to be their biggest weakness.
Aired: 05/07/18
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.
Why Triassic Animals Were Just the Weirdest
Why the Triassic was full of creatures that look a lot like other, more modern species.
Before a group of fish could live on dry land, they acquired the ability to breathe air.
Insects were the first animals to fly. Scientists are still working on how it happened.
420 million years ago, some fish wore armor – and it may have served a surprising purpose.
How Horses Took Over North America (Twice)
Horses vanished from North America for 10,000 years until a mammal brought them back.
Life, Sex & Death Among the Dire Wolves
Dire wolves were real! Their remains taught us a lot about how they lived.
When Giant Scorpions Swarmed the Seas
Sea scorpions thrived for 200 million years, coming in a wide variety of shapes and sizes.
