Researchers ran a climate model with Earth’s configuration during the Permian, when the land masses were combined in the supercontinent of Pangaea. “This is the first time that we have made a mechanistic prediction about what caused the extinction that can be directly tested with the fossil record, which then allows us to make predictions about the causes of extinction in the future,” said first author Justin Penn, a UW doctoral student in oceanography. The fossil is on display at the Idaho Museum of Natural History. The tooth whorl was located inside the shark’s lower jaw. This fossilized spiraling shark tooth is from the Helicoprion, an unusual shark that lived during the Permian. As temperatures rose and the metabolism of marine animals sped up, the warmer waters could not hold enough oxygen for them to survive. New research from the University of Washington and Stanford University combines models of ocean conditions and animal metabolism with published lab data and paleoceanographic records to show that the Permian mass extinction in the oceans was caused by global warming that left animals unable to breathe. What has been debated until now is exactly what made the oceans inhospitable to life – the high acidity of the water, metal and sulfide poisoning, a complete lack of oxygen, or simply higher temperatures. Some 96 percent of marine species were wiped out during the “Great Dying,” followed by millions of years when life had to multiply and diversify once more. Long before dinosaurs, our planet was populated with plants and animals that were mostly obliterated after a series of massive volcanic eruptions in Siberia.įossils in ancient seafloor rocks display a thriving and diverse marine ecosystem, then a swath of corpses. The largest extinction in Earth’s history marked the end of the Permian period, some 252 million years ago. Justin Penn and Curtis Deutsch/University of Washington The images below the line represent some of the 96 percent of marine species that died during the event. At the top is the supercontinent Pangaea, with massive volcanic eruptions emitting carbon dioxide. The color of the water shows the temperature change, with red being most severe warming and yellow less warming. ![]() A greater percentage of marine animals survived in the tropics than at the poles. ![]() This illustration shows the percentage of marine animals that went extinct at the end of the Permian era by latitude, from the model (black line) and from the fossil record (blue dots).
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