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

by Peter Brannen

Along with extremely high heat, devastating ocean acidification, and ozone destruction, other proposed Permian killers include: intense forest-killing acid rain from volcanic sulfur dioxide, brief blasts of cold from sun-blocking sulfur aerosols, agonizing respiratory death from the noxious slew of gases billowing out of the volcanoes (gases that would not have been unfamiliar on a World War I battlefield), direct carbon dioxide poisoning, and mercury toxicity. With so many potential killers running amok, Doug Erwin has humorously dubbed the glut of suspects at the end of the Permian the “Murder on the Orient Express” theory of mass extinction. “Only Dante could truly do this world justice,” he writes. “Yeah, so there’s certainly no shortage of killers,” said Kump. Add to this whodunit two more suspects—the horrifying specters of ocean anoxia and anoxia’s poisonous bedfellow, hydrogen sulfide, which can be produced by bacteria only in the absence of oxygen. If you’ve ever smelled rotten eggs, you know what hydrogen sulfide is. At only one part per million, it already starts to suffuse the air with the unmistakable miasma of rank shit. At 700 to 1,000 parts per million, you die instantly.