Episode 4: Iron Man

In this book, Leakey and Lewin discuss how human activities are leading to a catastrophic reduction in the number of plant and animal species on Earth. They argue that humans have become the primary cause of this sixth extinction, similar to the five major extinctions documented in the fossil record. The authors emphasize the need for humans to recognize their impact on the global ecosystem and to take conscious actions to mitigate this destruction.

In Under a White Sky, Elizabeth Kolbert takes a hard look at the new world we are creating. She meets biologists trying to preserve the world's rarest fish, engineers turning carbon emissions to stone in Iceland, Australian researchers developing a 'super coral' to survive on a hotter globe, and physicists contemplating shooting tiny diamonds into the stratosphere to cool the earth. Kolbert explores how human civilization's capacity for destruction has reshaped the natural world and how the very interventions that have imperiled our planet are increasingly seen as the only hope for its salvation. The book is by turns inspiring, terrifying, and darkly comic.