Eons

Join hosts Michelle Barboza-Ramirez, Kallie Moore, and Blake de Pastino as they take you on a journey through the history of life on Earth. From the dawn of life in the Archaean Eon through the Mesozoic Era — the so-called “Age of Dinosaurs” -- right up to the end of the most recent Ice Age.

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Episode 62, Season 1
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.

8:44
Episode 61, Season 1
Your Place in the Primate Family Tree

How did we get from a mouse-sized creature that looked more like a squirrel to you?

11:35
Episode 60, Season 1
When Giant Amphibians Reigned

A look at when Temnospondyls Amphibians existed for 210 million years

9:51
Episode 59, Season 1
Can We Get DNA From Fossils?

Scientists have been working for decades to unlock the genetic secrets of the past.

11:22
Episode 57, Season 1
When We First Walked

Human ancestors were already walking 3.6 million years ago. But who was first to walk?

10:56
Episode 56, Season 1
Life, Sex & Death Among the Dire Wolves

Dire wolves were real! Their remains taught us a lot about how they lived.

9:15
Episode 58, Season 1
Did Raptorex Really Exist?

Is LH PV18 a Tarbosaurus bataar? Or a different theropod named Raptorex kriegsteini?

12:27
Episode 55, Season 1
The Rise and Fall of the Bone-Crushing Dogs

What happened to the biggest dogs that ever lived?

8:29
Episode 54, Season 1
How a Supervolcano Made the Cenozoic’s Coolest Fossils

Yellowstone contains some of North America's most amazing fossil deposits.

9:15
Episode 53, Season 1
How Horses Took Over North America (Twice)

Horses vanished from North America for 10,000 years until a mammal brought them back.

9:08
Episode 52, Season 1
When Birds Had Teeth

How did Archaeopteryx relate to today’s birds? Its teeth provide a major clue.

11:29
Episode 51, Season 1
When Fish Wore Armor

420 million years ago, some fish wore armor – and it may have served a surprising purpose.

9:37
Episode 50, Season 1
The Mystery of the Eocene’s Lethal Lake

In the 1800s, miners found beautifully preserved fossils of animals from the Eocene.

7:59
Episode 46, Season 1
When Fish First Breathed Air

Before a group of fish could live on dry land, they acquired the ability to breathe air.

8:40
Episode 49, Season 1
When Insects First Flew

Insects were the first animals to fly. Scientists are still working on how it happened.

8:38
Episode 48, Season 1
FAQs From Our First Year

To celebrate our first anniversary together, we’d like to answer some of your questions.

9:20
Episode 45, Season 1
Where Did Viruses Come From?

Where did viruses come from and how did they evolve? Are viruses alive?

7:29
Episode 47, Season 1
How the T-Rex Lost Its Arms

Tyrannosaurus rex had tiny arms. How did this happen, and why did it keep them?

6:54
Episode 42, Season 1
From the Fall of Dinos to the Rise of Humans

The Cenozoic marks the rise of organisms that look a lot like us.

12:34
Episode 41, Season 1
The Weird, Watery Tale of Spinosaurus

In 1912, a fossil collector discovered the world’s only known semi-aquatic dinosaur.

7:28
Episode 44, Season 1
Why Triassic Animals Were Just the Weirdest

Why the Triassic was full of creatures that look a lot like other, more modern species.

9:07
Episode 43, Season 1
That Time It Rained for Two Million Years

234 million years ago, the climate suddenly changed for the wetter.

7:31
Episode 40, Season 1
The Age of Reptiles in Three Acts

Reptiles in time grew to become some of the largest forms of life ever to exist on earth.

10:45
Episode 39, Season 1
How the Chalicothere Split In Two

How did two of the same kind of animal end up looking so different?

7:03
Episode 38, Season 1
How the Squid Lost Its Shell

Ancestors of cephalopods all had shells until it proved to be their biggest weakness.

8:05
Episode 37, Season 1
What Was the Ancestor of Everything?

The search for our origins go back to a single common ancestor.

11:06
Episode 36, Season 1
Inside the Dinosaur Library

We talk to Amy Atwater, Collections Manager at the Museum of the Rockies.

7:19
Episode 35, Season 1
The Most Useful Fossils In The World

Mysterious fossils can be used to tell time in the deep past.

5:49
Episode 34, Season 1
What a Dinosaur Looks Like Under a Microscope

What has been observed and learned from putting dinosaur bones under a microscope.

8:09
Episode 33, Season 1
How the Turtle Got Its Shell

Where did turtles come from? And how did the they get their shells?

8:29
Episode 32, Season 1
The Other Explosion You Should Know About

The Sudden burst of diversity that marked the dawn of truly complex life on our planet.

6:25
Episode 30, Season 1
From the Cambrian Explosion to the Great Dying

The Paleozoic Era is one of the most chaotic times in Earth's history. Find out why!

10:28
Episode 31, Season 1
How Sex Became A Thing

Follow the early history of how (and why) sex became a thing.

5:39
Episode 28, Season 1
The Great Snake Debate

90 million years ago, an ancient snake known as Najash had...legs.

6:28
Episode 29, Season 1
The Whole Saga of the Supercontinents

So if we want to know how we got here, we have to understand how "here" got here.

8:40
Episode 27, Season 1
Untangling the Devil's Corkscrew

In the late 1800s, paleontologists in Nebraska found huge coils of hardened sand.

6:11
Episode 26, Season 1
The Time Terror Birds Invaded

5 million years ago, a predator made its way onto the coastal plains of North America.

5:32
Episode 25, Season 1
How Two Microbes Changed History

More than two billion years ago, a tiny living thing started to live inside another thing.

7:39
Episode 24, Season 1
When Giant Fungi Ruled

An unlikely group of pioneers ultimately made life on land possible -- the fungi.

6:37
Episode 21, Season 1
The Facts About Dinosaurs & Feathers

Dinosaurs have been found with some sort of fluff or even full-on plumage.

10:01
Episode 22, Season 1
The Last Time the Globe Warmed

Imagine an enormous, lush rainforest teeming with life...in the Arctic.

9:54
Episode 17, Season 1
When Whales Walked

We know whales as graceful giants bound to the sea.

4:56
Episode 19, Season 1
A Brief History of Geologic Time

Geologists have been able to identify crucial episodes in life’s history.

12:08
Episode 20, Season 1
The Search for the Earliest Life

Even in a hellish environment, life found a way.

5:37
Episode 15, Season 1
When The Earth Was Purple

But imagine a time when the Earth looked a little … purple.

5:37
Episode 18, Season 1
An Illustrated History of Dinosaurs

Our image of dinosaurs has been constantly changing since naturalists started studying the

12:20
Episode 16, Season 1
Living Fossils' Aren't Really a Thing

Even the most ancient-looking organisms show us that evolution is always at work.

5:05
Episode 23, Season 1
What Happened to the World's Greatest Ape?

Gigantopithecus is the greatest great-ape that ever was.

7:01
Episode 13, Season 1
History's Most Powerful Plants

Fossil fuels are made from the remains of extinct organisms.

5:20
Episode 14, Season 1
How Did Dinosaurs Get So Huge?

Creatures as tall as a five-story buildings shook the Earth.

5:42
Episode 12, Season 1
The Age of Giant Insects

Insects and other arthropods weren’t always so small.

5:28
Episode 10, Season 1
The Extinction That Never Happened

Natural history is full of living things that were long thought to have gone extinct only

7:36
Episode 9, Season 1
Dimetrodon: Our Most Unlikely Ancestor

Take a close look and you might see a little bit of yourself.

5:21
Episode 11, Season 1
The Strange Case of the Buzzsaw Jaws

A 270-million-year-old sea creature called Helicoprion that once swam the seas.

3:54
Episode 8, Season 1
The Biggest Thing That Ever Flew

Today, we’re familiar with two types of flying vertebrates -- birds and bats.

4:27
Episode 7, Season 1
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?

4:45
Episode 6, Season 1
The Story of Saberteeth

Smilodon was a fearsome Ice Age cat, the size of a modern-day tiger.

5:26
Episode 5, Season 1
What Colors Were Dinosaurs?

We know a lot about dinosaurs but there’s one question that has plagued paleontologists..

5:02
Episode 4, Season 1
Stegosaurs: Tiny Brains & Thagomizers

If you take it as a given that extinct dinosaurs were all weird and wonderful, then you go

4:49
Episode 3, Season 1
The Tully Monster & Other Problematic Creatures

There are animals in the fossil record that challenge some of our most basic ideas..

4:01
Episode 2, Season 1
When Did the First Flower Bloom?

During the Cretaceous Period, dinosaurs were more diverse, more fierce, and more strange.

4:21
Episode 1, Season 1
The Trouble With Trilobites

Trilobites are famous not just because they were so beautifully functional..

6:46

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