Cosmos: A Spacetime Odyssey

Ninth Episode:
the Lost Worlds of Planet Earth: Few animals larger than a hundred pounds survived the catastrophes of the late Cretaceous. The dust cloud brought night and cold to the surface for months. The dinosaurs froze and starved to death. But there were small creatures who took shelter in the Earth. And when they emerged they found that the monsters who had hunted and terrorized them were gone. The Earth was becoming the Planet of the Mammals. And the Earth continued its ceaseless changing.