Microbe May Have Caused Permian Extinction, Scientist Says

A scientist suggests that a microbe may have caused the Permian extinction, which killed 90 percent of the Earth's species around 251 million years ago.

The Permian extinction was one of the biggest catastrophes that caused a majority of the land and aquatic species to become extinct. Until now, the causes that triggered the collapse of the Permian period have remained a mystery.

Some have hypothesized that an asteroid strike or a volcanic eruption in an area, what is now called Siberia, led to a significant rise in greenhouse gas emissions and caused the mass extinction of the Earth's species.

However, researcher Daniel Rothman of the Massachusetts Institute of Technology, insists that the analysis of sedimentary samples belonging to the end-Permian period from China does not seem to match the facts, reports The New Scientist.

Sediment samples that were examined suggest that the carbon levels increased rapidly, which Rothman believes could not have been caused by geological processes, as they do not have the ability to generate carbon that fast. But microbes have the ability to increase carbon compounds at a faster rate, he said.

Rothman and his research team examined the genome of Methanosarcina, which are anaerobic methanogens that can form multicellular colonies. They are methane-producing bacterium and are responsible for producing biogenic methane in the absence of oxygen.

According to the researchers, Methanosarcina methanogens has the ability to produce large amounts of methane quickly. To produce methane, microbes require nickel. Further analysis of the sediment cores revealed that the nickel levels increased around 251 million years ago, which matches with the time when the mass extinction of the Permian period took place.

The increase in nickel levels was probably because of the presence of Siberian lavas that were rich in the metal during that time. This could mean that the Methanosarcina microbes triggered the mass extinction, The New Scientist report said.

The findings of the study were presented at the American Geophysical Union meeting in San Francisco two weeks ago.