The Secret Extinctions Of The Silurian Period

Take the PBS Digital Studios Audience Survey: The Eons Calendar: What graptolites tell us is a story of incredible changes in the ocean, of periods where the oceans became poisonous and suffocating before eventually clearing up again. They unlock extinctions and recoveries that scientists didn't see. And, most of all, they show us how unpredictable the Silurian period really could be. ***** PBS Member Stations rely on viewers like you. To support your local station, go to ***** Produced by Complexly for PBS Digital Studios Super special thanks to the following Patreon patrons for helping make Eons possible: Collin Dutrow, Pope John XII, Steven Kern, Aaditya Mehta, AllPizzasArePersonal, John H. Austin, Jr., Alex Hackman, Amanda Ward, Stephen Patterson, Karen Farrell, Trevor Long, Jason Rostoker, Jonathan Rust, Mary Tevington, Bart & Elke van Iersel - De Jong,