The oldest fossil evidence of life on land has been discovered in Australian rocks, potentially extending the known era of land-based life by over 500 million years.
Ancient deposits from a hot spring in Western Australia’s Pilbara region were found to contain minerals created by microbes, and researchers from the University of NSW were able to show that the deposits were created by land-based hot springs, rather than in the ocean.
The extraordinary finding suggests the earliest life may have actually originated in the hot springs on land, rather than in thermal vents deep in the ocean. It also has implications for the search for evidence of ancient life on Mars, because the Dresser Formation in the Pilbara region where the deposits were found shares some characteristics with Martian rock sites.
“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 the lead researcher, University of NSW PhD candidate Tara Djokic.
“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,” said Ms Dokic, the lead author in the study published in the journal Nature Communications.