Around 252 million years ago, more than 96 percent of marine species and 70 percent of land species disappeared in a geological instant. This mass die-off has become known as the end-Permian mass extinction. What was its cause?

Scientists now think that massive volcanic activity, in a Large Igneous Province called the Siberian Traps, raised air and sea temperatures and released toxic amounts of greenhouse gases into the atmosphere over a very short period of time. Massachusetts Institute of Technology researchers Samuel Bowring and Seth Burgess explain in this video how they figured out that the Siberian Traps erupted at the right time, and for the right duration, to have been a likely trigger for this great dying.