As long ago as forever and as far away as home, life was withering away wherever you looked. At the end of the Permian, around 250 million years ago, the creatures of Earth were devastated by an extinction that outstripped any seen before or since. Marine species suffered the most — 96% of them died out — but even among their terrestrial cousins, seven out of every ten species were lost. For countless generations, life struggled towards recovery, but it took 10 million years to rebuild the lost diversity. The cause of the catastrophe has long puzzled scientists; global warming, massive volcanos, ocean acidification, and widespread oceanic oxygen depletion have all been implicated. In a paper appearing in Science, researchers from the UK, Germany and Austria showed that increased carbon released into the atmosphere eventually acidified the oceans just as the Permian extinction reached its peak; comparing their findings with how quickly our societies release carbon, they reveal an alarming difference together with a sobering insight.
Clarkson MO, Kasemann SA, Wood RA, Lenton TM, Daines SJ, Richoz S, Ohnemueller F, Meixner A, Poulton SW, & Tipper ET (2015). Ocean acidification and the Permo-Triassic mass extinction. Science (New York, N.Y.), 348 (6231), 229-32 PMID: 25859043