3550000000 BC-02-23 21:40:38
New studies suggest all life (plants and animals) came from a single celled organism and this organism lived 3.55 bya. http://news.nationalgeographic.com/news/2010/05/100513-science-evolution-darwin-single-ancestor/ Advanced forms of life existed on earth as early as 3.55 billion years ago as evidenced by structures in Australia that resemble stromatolites. Uncontested microfossils and chemical traces of life were present at least by 2.7 billion years ago
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