The Ends of the World: Volcanic Apocalypses, Lethal Oceans, and Our Quest to Understand Earth's Past Mass Extinctions

by Peter Brannen

What is going on today is extremely unusual. We’re hunting and destroying animals at unfathomable rates, but if humanity were to disappear tomorrow, the planet might quickly recover. If we stopped dumping carbon into the atmosphere and ocean, in a few thousand years it would come out of the system as limestone. But we’re not likely to stop anytime soon, and alas, our plunder can’t go on forever without unleashing geologically significant devastation. In 2011, UC Berkeley paleontologist Anthony Barnosky and his colleagues published the paper “Has the Earth’s Sixth Mass Extinction Already Arrived?” Judging by the coverage of the paper in the popular press, the answer seems to be an unequivocal yes. But in fact the paper predicted that the planet would reach Big Five levels of extinction only after hundreds to several thousands of years of continued and unabated environmental destruction. This outcome would still be instantaneous from a geological point of view, but from a human perspective the sixth mass extinction is still, thankfully, a little ways off.