Centuries ago, Charles Darwin said the origin of life could have occurred in “some warm little pond” and now that evicence of life has been found in 3.48 billion-year-old Australian rocks.
It gives credence to the scientific belief that origin of life on Earth arose in small, terrestrial ponds, or deep in the ocean. It could lead us to find similar life origin ponds on Mars, said the researchers who are upbeat about their new finding.
Previously it was thought that the origin of life could have begun some 2.7 to 2.9 billion years ago as found in some deposits in South Africa. Now that the Australian deposits are 3.48 billion years old, the theory that life started evolving much earlier than believed so far.
Secondly, the new findings negate the belief that life began in ocean and extended to land. “Our exciting findings don’t just extend back the record of life living in hot springs by 3 billion years, they indicate that life was inhabiting the land much earlier than previously thought, by up to about 580 million years,” said Tara Djokic from the University of New South Wales (UNSW) in Australia.
“This may have implications for an origin of life in freshwater hot springs on land, rather than the more widely discussed idea that life developed in the ocean and adapted to land later.”
Djokic and her colleagues found the incredibly well-preserved deposits of the ancient Dresser Formation in the Pilbara Craton of Western Australia which they believed were remnants of a long-lost marine environment, but new evidence suggests it otherwise.
The Dresser Formation contains a clear signature of land – a mineral called geyserite, which is found exclusively in the surroundings of terrestrial hot springs and geysers.
Further, a number of potential new ‘biosignatures’ in the deposits, including two different types of stromatolites – layers of sediment packed together by ancient, water-based bacterial colonies – called iron-rich domical and conical stromatolites supported their new theory.
The team is confident that the new finding also applies to the belief that alien life is possible on Mars where similar deposits were found by NASA scientists.
The research has been published in Nature Communications.