Oxygen arrived early to support life on Earth: Study

London, Feb 17 (IANS) The oxygenation of Earth’s atmosphere to support life happened 3.8 billion years ago — some 0.7-0.8 billion years earlier than previously thought, scientists report.

Researchers across the world agree that oxygenation happened in two major steps: the first during the so-called “Great Oxidation” Event about 2.5-2.4 billion years ago and the second during the Late Neoproterozoic Era around 750 to 540 million years ago.

The latter is thought to have been the cause for the emergence of animals during the so-called “Cambrian explosion” nearly 540-520 million years ago.

The discovery opens up for the possibility of evolution of the earliest primitive photosynthetic life forms as early as 3.8 billion years ago.

“It is generally believed that early Earth was completely anoxic (without oxygen) but our study shows that the surface of the Earth was exposed to a low oxygen atmosphere already by this time,” explained lead researcher Robert Frei from University of Copenhagen.

To reach this conclusion, the researchers analysed Earth’s oldest banded iron formations (BIFs) from Western Greenland.

BIFs are marine chemical sediments and retain information on the composition and presence of oxygenation/reduction processes in ambient seawater and on the interaction of the atmosphere with Earth’s surface.

The analyses of the BIF layers from Western Greenland show elements that require presence of oxygen in the atmosphere.

“This has far reaching implications for how we investigate the pace of evolution of life and its biodiversity on our planet,” the authors noted in a paper published in Nature’s Scientific Reports.

Leave a Reply

Please enter your comment!

The opinions, views, and thoughts expressed by the readers and those providing comments are theirs alone and do not reflect the opinions of www.mangalorean.com or any employee thereof. www.mangalorean.com is not responsible for the accuracy of any of the information supplied by the readers. Responsibility for the content of comments belongs to the commenter alone.  

We request the readers to refrain from posting defamatory, inflammatory comments and not indulge in personal attacks. However, it is obligatory on the part of www.mangalorean.com to provide the IP address and other details of senders of such comments to the concerned authorities upon their request.

Hence we request all our readers to help us to delete comments that do not follow these guidelines by informing us at  info@mangalorean.com. Lets work together to keep the comments clean and worthful, thereby make a difference in the community.

Please enter your name here