- The largest mass extinction in Earth’s history was due to methane-producing microbe.
- Around 90% of all species on earth were wiped out 252 million years ago,as seen through fossil remains.
- To reveal the culprit, evidence has been found by MIT researchers and to examine the killers they would require a microscope.
- The earlier implicated perpetrators asteroids, volcanoes or raging coal fires were not responsible. Rather,a form of microbes,methane-producing Archaea called “Methanosarcina” were the cause which suddenly explode in ocean, spewing huge amount of methane into atmosphere, changing the climate and chemistry of the oceans.
- Geochemical evidence – there was increase of carbon dioxide in the oceans at end-Permian extinction.
- Genetic evidence – a change in “Methanosarcina”, previously an accumulator of carbon dioxide,became a emitter of methane.
- Sediments evidence – sudden increase in the amount of nickel deposited at that time.
Exams Perspective:
- Asteroids
- Methanosarcina
- Reasons for Mass Extinction of Species