By creating an account, you acknowledge that PBS may share your information with our member stations and our respective service providers, and that you have read and understand the Privacy Policy and Terms of Use.
Become a WSIU member to enjoy
WSIU | Passport
Get extended access to 1600+ episodes, binge watch your favorite shows, and stream anytime - online
or in the PBS app.
Season 3 Episode 12 | 7m 42s
| Video has closed captioning.
The rise and fall of ancient walruses, and how modern ones got their tusks, is a story that spans almost 20 million years. And while there are parts of the story that we’re still trying to figure out, it looks like tusks didn’t have anything to do with how or what these animals ate.
Join hosts Hank Green, 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.