nprfreshair:Rebroadcasting today: Elizabeth Kolbert author of The Sixth Extincti...printnprfreshair:Rebroadcasting today: Elizabeth Kolbert author of The Sixth Extincti...January 24, 2015 · originally posted on Tumblrnprfreshair:Rebroadcasting today: Elizabeth Kolbert author of The Sixth ExtinctionIn The World’s ‘Sixth Extinction,’ Are Humans The Asteroid?