3.7-billion-year-old fossils may be oldest signs of life on Earth
Post date: Sep 2, 2016 2:13:01 PM
By Joel Achenbach WASHINGTON POST AUGUST 31, 2016
WASHINGTON — Scientists probing a newly exposed, formerly snow-covered outcropping in Greenland claim they have discovered the oldest fossils ever seen, the remnants of microbial mats that lived 3.7 billion years ago.
It’s a stunning announcement in a scientific field that is always contentious. But if confirmed, this would push the established fossil record more than 200 million years deeper into the Earth’s early history, and provide support for the view that life appeared very soon after the Earth formed and may be commonplace throughout the universe.
A team of Australian geologists announced their discovery in a paper titled “Rapid emergence of life shown by discovery of 3,700-million-year-old microbial structures,” published Wednesday in Nature.
a, Geological map covering the described localities. The outcrops for localities A, B and C are indicated. b, Position of locality in the ISB. c, Panoramic view towards the southeast over the described localities. In the foreground are the banded iron formation and chert outcrops in the northwest corner of the map a. The 15–20 m thick Ameralik dyke forms the skyline.
Figure 1: ISB site A stromatolites and younger ones from Western Australia. a, Site A stromatolites.close
Image is inverted because layering is overturned in a fold. b, Interpretation of a, with isolated stromatolite (strom) and aggregate of stromatolites (stroms). Locally, lamination is preserved in the stromatolites (blue lines).