3.7-billion-year-old fossils show early life


A sample from the 3.7-billion-year-old stromatolite fossils. The stromatolites are small wave-like mounds in this image. Image via Allen P. Nutman/ Nature.

Scientists have uncovered 3.7-billion-year-old fossils in Greenland that have set a new record for the earliest-known evidence of life on Earth. They show that stromatolites, which are layered sediments produced over time by single-celled microbes. The fossils indicate that these living microbes were already present in an ancient shallow sea on our very young planet. Australian researchers made the discovery. Their findings were published in the September 1, 2016 issue of Nature.
Prior to this discovery, the earliest-known traces of life were in 3.5 billion-year old stromatolite fossils found in western Australia. The new findings predate it by 220 million years.

Allen Nutman and Vickie Bennett hold one of the fossil specimens from Greenland that date to 3.7 billion years. Image courtesy of Allen Nutman.

Earth scientist Allen Nutman from the University of Wollongong led the team that made the discovery. In a statement, he said: