MIT: Earth’s End-Permian Mass Extinction Occurred More Quickly Than First Thought

Asteroid impact, volcanic eruptions, and cataclysmic environmental events are all thought to have contributed to the world's largest mass extinction 252 million years ago when 96% of marine species and 70% of land inhabitants were wiped out. Researchers from the Massachusetts Institute of Technology believe that the catastrophic occurrence happened much quicker than previously believed.

Sam Bowring, the Robert R. Shrock Professor of Earth and Planetary Sciences at MIT, has been conducting this study since 2006 with students and colleagues. It wasn't until now, though, that they have been able to determine that the end-Permian extinction occurred over 60,000 years, which is ten times faster than previously projected. The extinction was the closest life has come to being completely eliminated. Other statistics and facts about the extinction can be found in this MIT News article.

Bowring and one of his graduate students, Seth Burgess, discovered that the oceans experienced a pulse of light carbon 10,000 years before the die-off. They believe that this may have attributed to ocean acidification, which would have increased the water temperature by ten degrees Celsius, in turn killing most of the sea life. The presence of carbon in the ocean as well as the atmosphere was believed to be caused by long-lasting volcanic eruptions from the Siberian Traps. Bowring and Burgess are currently using similar dating techniques they used to determine the extinction to unveil the Permian period's volcanic eruptions.

"It is clear that whatever triggered extinction must have acted very quickly," says Burgess in this EurekAlert! article."...fast enough to destabilize the biosphere before the majority of plant and animal life had time to adapt in an effort to survive." Burgess is also the lead author of a paper that reports the results in this week's Proceedings of the National Academy of Sciences.

Bowring and Burgess have been examining rock samples from Meishan, China; a region whose rock formations are believed to provide evidence of the end-Permian extinction. The team reported back in 2011 that the extinction lasted less than 200,000 years based on the analysis of the rocks. But their research wasn't extensive or precise enough to determine what actually caused the extinction.

They believe they have found concrete answers from their most recent measurements after determining a more precise "age model" for the extinction, citing the ocean behavior the most revealing determinant.

To read more about this study, visit this EurekAlert! article.