Meet the killer microbe that caused Earth's worst mass extinction

Methanosarcina, an ancient group of methane-producing microbes, has been named as the culprit behind the Permian mass extinction 252 million years ago, the worst mass extinction in Earth's history that killed off 95% of all life.

Sometimes bad things come in small packages, as in the case of Methanosarcina, a methane-producing microbe that's been blamed for the worst mass extinction in Earth's history. 

A microbe that spewed humongous amounts of methane into Earth’s atmosphere triggered a global catastrophe 252 million years ago that wiped out upwards of 90% of marine species and 70% of land vertebrates.