Single Microbe May Have Triggered the "Great Dying"

An anonymous reader writes with an excerpt from Medical Daily about a new theory for what triggered the "Great Dying: " "Researchers believe that they may finally know why the event occurred, but the theory is not without controversy. There are several theories, including the possibility of a meteorite hitting the planet. Previously, most researchers believed that the Permian mass extinction was a result of a series of volcanic eruptions in what is now Siberia. ... However, Daniel Rothman from the Massachusetts Institute of Technology is floating around a different theory. As he presented in a meeting for the American Geophysical Union, he believes that the mass extinction could have been caused by something much smaller. His theory is that the extinction was caused by a single strain of bacteria."

Comments

Cofactor F430

[epine]

Cofactor F430

Forget the organism. This is about the advent of a novel reaction pathway, that scales on the availability of nickel. Surprisingly, geology might have something to say on that score. Any vigorous reaction pathway that bubbles madly away at an oceanic scale is almost certain to colour the infrared signature of our thin gas membrane. Imagine if everyone on the planet had an F430.

There's a lot to like about this hypothesis. I've seen worse. To determine exactly how this pathway becomes prolific at global scale would take decades of further study. It's as yet a humble beginning, of the kind that sometimes pans out.

This has happened twice ... could it happen again?

[Chrisq]

If this is correct it is the second time an organism has wiped out most existing life forms The Great Oxygenation Event is thought to have killed most existing forms of life - then single-celled organisms. It makes you wonder, could it happen again - a bacteria completely changing Earth's chemistry in a way that's incompatible with most existing life forms?