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Sign up for our mailing list!\n\nIt's another extinction event episode! This one's about the end-Permian AKA the Permian-Triassic AKA the GREAT DYING.\n\nFurther Reading:\n\nAncient mini-sharks lived longer than thought\n\nLystrosaurus's fossilized skeleton:\n\n\n\nLystrosaurus may have looked something like this but I hope not:\n\n\n\nThis artist's rendition of lystrosaurus looks a little less horrific but it might not be any more accurate:\n\n\n\nShow transcript:\n\nWelcome to Strange Animals Podcast. I\u2019m your host, Kate Shaw.\n\nIt\u2019s time for our next extinction event episode, and this week it\u2019s the big one. Not the extinction event that killed the dinosaurs, but one you may not have heard of, one that almost destroyed all life on earth. I mean, obviously it didn\u2019t and things are fine now, but it was touch and go there for a while. It\u2019s the Permian-Triassic extinction event, or end-Permian, which took place just over 250 million years ago. It was so bad that scientists who aren\u2019t given to hyperbole refer to it as the Great Dying.\n\nDon\u2019t worry, we won\u2019t talk about extinction the whole time. We\u2019ll also learn about some interesting animals that survived the extinction event and did just fine afterwards.\n\nWe have a better idea of what happened at the end of the Permian than we have about the earlier extinction events we talked about in episodes 205 and 214. Right about 252 million years ago, something caused a massive volcanic eruptive event in what is now Siberia. Some researchers speculate that the cause of the volcanic eruptions may have been a huge asteroid impact on the other side of the Earth, which was so powerful that it caused magma to move away from the impact like water sloshing in a jostled glass. The magma rose up toward the earth\u2019s crust and eventually through it onto the surface.\n\nThe result was probably the largest volcanic event in the last half-billion years and it continued for an estimated two million years. Most of the eruptions were probably pretty low-key, just runny lava pouring out of vents in the ground, but there was just so much of it. Lava covered almost a million square miles of land, or 2.6 million square km. Ash and toxic gases from some eruptions also ended up high in the atmosphere, but one big problem was that the lava poured through sediments full of organic material in the process of turning into coal. Lava, of course, is molten rock and it\u2019s incredibly hot. It\u2019s certainly hot enough to burn a bunch of young coal beds, which added more ash and toxic gases to the air\u2014so much ash that shallow water throughout the entire world became choked with ash.\n\nThe carbon dioxide released by all that burning coal caused severe ocean acidification and ocean anoxia\u2014a lack of oxygen in the water. But it gets worse! A lot of lava erupted into the ocean right at the continental shelf, where the shallow coastal water becomes much deeper. This is exactly the place where you find methane deposits in the sediments on the ocean floor. When those deposits were suddenly disturbed by lava flowing into them, all the methane in the formerly tranquil depths was released and bubbled to the surface. Methane is a powerful greenhouse gas, meaning that if a whole lot of it ends up in the atmosphere in a short amount of time, it can cause rapid global warming\u2014much faster than that caused by carbon dioxide. This global warming would have happened after a period of global cooling due to reduced sunlight reaching the earth through ash clouds, which lasted long enough and was severe enough that sea levels dropped as glaciers formed. Then everything heated way, way up. The ice caps melted, which may have led to a stagnation of ocean currents. This in turn would have contributed to the water\u2019s anoxicity and toxicity. The average temperature of the ocean would have increased by almost 15 degrees Fahrenheit, or 8 degrees Celsius. Atmospheric warming may have been as much as 68 degrees Fahrenheit in places,