252 million years ago 90% of the life on the planet got snuffed. A new hypothesis suggests that it wasn't the butler, but rather zillions of methane-making microbes that did it.
http://www.latimes.com/science/scie...n-extinction-microbes-20140401,0,818600.story
http://www.latimes.com/science/scie...n-extinction-microbes-20140401,0,818600.story