An eruption-fueled extinction?
Around 250 million years ago, the most devastating mass extinction in Earth’s history marked a definitive end to the Permian geologic period. The global event extinguished more than 90 percent of the planet’s marine species and 70 percent of its terrestrial species. Exactly what caused the collapse has been an ongoing puzzle for scientists: Their theories have included massive volcanic eruptions, an asteroid impact and the formation of the supercontinent Pangaea. Now researchers at MIT and elsewhere have found fresh evidence that the mass extinction may have been triggered by enormous volcanic eruptions that gave rise to the Siberian Traps, a wide expanse of volcanic rock in present-day Russia. The researchers discovered that these eruptions spewed vast amounts of gases into the atmosphere, possibly setting off a cascade of environmental effects that led to the end-Permian collapse....