Back and Forth on the Oxygen Train – #365papers – 2017 – 19

#365papers for January 19, 2017

Kipp, Stueken, Bekker, and Buick, 2017, Selenium isotopes record extensive marine suboxia during the Great Oxidation Event: Proceedings of the National Academy of the Sciences.

What’s it about?

Sometime longabouts 2.3 and 2.1 billion years ago, Earth’s atmosphere became oxygenated and organisms came about that utilized oxygen extensively in their metabolic processes. However, these organisms did not come to dominate on the Earth until a billion years later. During this Great Oxidation Event, despite increases in oxygen overall in the atmosphere and the oceans, there were periods of more or less oxygen, which made it hard to oxygen-dependent organisms to proliferate.

Why does it matter?

When we talk about the origins of complex life on this planet, we need to address the origins of eukaryotes, organisms whose cells have the DNA held in a nucleus and who are dependent upon oxygen for metabolic processes. Thus, the nature of the initial oxygenation of the atmosphere is important to understanding our own origins.

Why did I read this?

This paper had some components that always catch my eye, particularly isotopes and extinction. It also had been all over the news, so I decided that I ought to give it a read.