So how did life evolve through all of this chaos? The SETI Institute is a multi-disciplinary, highly collaborative research organization committed to exploring, understanding, and explaining the origin, nature and prevalence of life in the universe. As for the dome- and cone-forms of the fossils, those are typical shapes seen where rocks of different strengths have been squeezed and stretched.
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September 1,2016- Fossils as defined in a dictionary are the remains or impression of a prehistoric plant or animal embedded in rock and preserved in petrified form.
Many claims of early fossils have fallen on close examination. They also suggest that chemical analyses showing differences in trace element concentrations inside and outside the bumps match patterns seen in stromatolites elsewhere. Animal and plant secretion, such as amber, is also evidence of life and therefore a fossil.
That’s because most rocks this old have been heavily altered by heat and plate tectonics in the billions of years since they formed. “We have a much better window back in time, thanks to what these folks did”.
The Greenland structures are about 220 million years older than the oldest widely accepted evidence for life, a set of stromatolites from the Pilbara region of western Australia. However, the paper is contested as there could be alternate explanations for these chemical anomalies. Stromatolites are small, layered mounds of sediment built by mats of microbes living in shallow water.
Stromatolites in the Soeginina Beds (Paadla Formation, Ludlow, Silurian) near Kübassaare, Saaremaa, Estonia.
The nature of the fossil record shows these single-celled organisms were already co-operating as communities 3.7 billion years ago. Discoveries kept pushing the start date for life further into the past.
Closer to home, Mars remains the top target for the search for extraterrestrial life, and the Greenland discovery, if it holds up, suggests that the investigation on Mars should include a hunt for fossilised stromatolites. Today, they are locked away in hard metamorphic rock-particularly, a 3.7-billion-year-old belt of stone called the Isua Greenstone Belt.
The newly discovered stromatolites were found to be one to four centimetres thick, considered high. A team led by Allen Nutman, a geologist at the University of Wollongong in Australia, visited a rock outcrop that had been buried under a perennial snow patch until warmer temperatures melted it away.
The fossil discovery provides proof for a proposal first advanced way back in 1996, about geochemical signatures on these rocks as having been that of bacteria’s.
“This cataclysm, known as the Late Heavy Bombardment, hit Earth between 3.9 and 3.8 billion years ago”. Previous genetic molecular clock studies point to such a time as well. These findings take us one inch closer to legitimately using “aliens” in a headline one day. The setting and complexity of the stromatolites indicates sophisticated life systems had been established less than one billion years after Earth formed. “Give life half an opportunity and it’ll run with it”, she added.
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Professor Martin Van Kranendonk, Director of the Australian Centre for Astrobiology at UNSW, of which Professor Nutman is also an Associate Member, said it was a groundbreaking find that could point to similar life structures on Mars, which 3.7 billion years ago was a damp environment. The find may help guide scientists searching for life on other planets.
