Researchers Propose a Solution to the Delayed Earth's Oxygenation

Saturday, July 13, 2019 - 13:05

The existence evidences of the earth history and planetary science claims that oxygen-releasing photosynthesis evolving much earlier, perhaps as early as 3 billion years ago.

According to the web-based science, research, and technology news service,, the oxygen-rich atmosphere we take for granted today has existed for only about 10 percent of Earth's 4.5-billion-year history.

Recently, researchers of the School of Earth and Atmospheric Sciences (EAS), Christopher Reinhard, an assistant professor, former EAS postdoctoral researcher Kazumi Ozaki, and collaborators published their findings in Nature Communications; suggest that in the oceans of early Earth, oxygen-releasing photosynthesizers could not compete effectively with their primitive counterparts.

Modern photosynthesizers consume water and release oxygen. Primitive ones instead consume dissolved iron ions—which would have been abundant in the oceans of early Earth. They produce rust as a byproduct instead of oxygen.

Using experimental microbiology, genomics, and large-scale biogeochemical modeling, "we found that photosynthetic bacteria that use iron instead of water are fierce competitors for light and nutrients," says Ozaki, the paper's first author and now an assistant professor in the Department of Environmental Science at Toho University, in Japan.

"We propose that their ability to outcompete oxygen-producing photosynthesizers is an important component of Earth's global oxygen cycle. We want to understand the timing of major biological innovations and their impact on the chemistry of Earth's oceans and atmosphere. We consider these principles to be central in understanding our own evolutionary origins and the search for life beyond our solar system."


Popular News

Latest News