Scientists Discover 3.7 Billion-Year-Old Fossil In Greenland, Could This Be The Oldest Fossil On Earth?
Scientists believe that they have found the oldest ever fossil on unearthed on the surface of Earth aging 3.7 billion years old. Back then during the fossil's time, Earth has orange skies and green oceans.
The fossil was found in a newly melted part of Greenland where the scientists were studying what seemed to be the leftover structure of a group of microbes living below the ancient seafloor. The fossil signifies that life may have formed quicker and easier than believed, which is half a billion years after Earth was formed.
This implies that life elsewhere other than Earth may have formed, said Martin VanKranendonk of the University of New South Wales, Director of the Australian Center for Astrobiology. He said, "It gives us an idea how our planet evolved and how life gained a foothold."
Previous studies suggest that it would take more than half a billion years before life forms on the once molten Earth. But this fossil discovery showed that it could happen quicker instead. The Phys.org reported that the newly discovered fossil is actually far too complex than the other first life forms known.
The Australian team found stromatolites (about 0.4 to 1.6 inches in height) in an outcrop of rock that used to be covered in ice and snow. Fortunately, warm spring melted the area and showed the intricately layered microscopic structures that are undoubtedly made by microbes. VanKranendonk said that the fossil looked like the house left and made by the microbes.
With the standard dating method using tiny zircon with uranium and lead, the team was able to date the fossil back to 3.7 billion years ago. "It would have been a very different world. It would have had black continents, a green ocean with orange skies," he said. He continued that the land is probably colored black due to continuous lava flow making it impossible for plants to form. In the other hand, iron made the ocean green. The atmosphere also lacks oxygen which makes the sky blue, therefore the predominant color would have been orange.
According to NASA's astrobiologist Abigail Allwood, the dating seems to be correct. She was the one who unearthed the previous oldest fossil which was 3.48 billion years old. However, she wasn't convinced that the fossil once had a life since the evidence was not as conclusive as she expected. The study was published in the journal Nature.