The final chapter brings all the book’s threads together. It explores the similarities and differences between the Anthropocene defaunation and the ancient mass extinctions. It investigates how much time we have before we reach the extinction levels of the Big Five mass extinctions. It has been suggested that we should just let the defaunation run its course; but the consequences of that course of action appear dire. But all Is not lost. The fossil record shows that the Earth System is resilient, and if we quickly act to remove the climatic forcings we are creating, we have time to turn the situation around and avoid sliding into another full-blown mass extinction.