Episode 1: What Happened to the World's Biggest Beaver?

Episode 2: The Reign of the Hell Ants

Episode 3: The Pandemic That Lasted 15 Million Years

Episode 4: When We First Talked

Episode 5: The Return of Giant Skin-Shell Sea Turtles

Episode 6: The Genes We Lost Along the Way

Episode 7: Our Bizarre, Possibly Venomous, Relative

Episode 8: How Worm Holes Ended Wormworld

Episode 9: How Humans Became (Mostly) Right-Handed

Episode 10: How Chilis Got Spicy (and Why We Love the Burn)

Episode 11: How To Survive the Little Ice Age

Episode 12: When Crocs Thrived in the Seas

Playing

Episode 13: When Trees Took Over the World

Episode 14: How Weasels Got Skinny

Episode 15: Where Are All The Squid Fossils?

Episode 16: Did These Giant Sloths Poop Themselves to Death?

Episode 17: The Traits That Spawned the Age of Mammals

Episode 18: The Island of the Last Surviving Mammoths

Episode 19: Where Are All the Medium-Sized Dinosaurs?

Episode 20: How the Starfish Got Its Arms

Episode 21: The Creature That Stumped Darwin

Episode 22: How Pollination Got Going Twice

Episode 23: How a Supervolcano Ignited an Evolutionary Debate

Episode 24: How a Mass Extinction Event Created the Amazon

Episode 25: When Mammals Only Went Out At Night

Episode 26: How Ancient Whales May Have Changed the Deep Ocean

Episode 27: How Dinosaurs Coupled Up

Episode 28: When It Was Too Hot for Leaves

Episode 29: Why The Paleo Diet Couldn't Save The Neanderthals

Episode 30: The Fossil Record In Your Mouth

Episode 31: When Pterosaurs Walked