Geology: Evidence of life in Earth's oldest rocks

  title={Geology: Evidence of life in Earth's oldest rocks},
  author={Abigail C. Allwood},
  • A. Allwood
  • Published 31 August 2016
  • Geology, Environmental Science, Geography
  • Nature
When did life first arise on Earth? Analysis of ancient rocks in Greenland that contain structures interpreted as bacterial in origin suggest that Earth might have been an abode for life much earlier than previously thought. See Letter p.535 Stromatolites are sedimentary formations created by the layered growth of microorganisms in shallow marine settings. Fossil stromatolites constitute some of the earliest evidence for life on Earth. Allen Nutman et al. describe metamorphosed stromatolites… 

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An objective Bayesian analysis of life’s early start and our late arrival

  • D. Kipping
  • Geology
    Proceedings of the National Academy of Sciences
  • 2020
The chronology of Life emerged on Earth within the first quintile of its habitable window, but a technological civilization did not blossom until its last, and for intelligence evolution, it is found that a rare-intelligence scenario is slightly favored at 3:2 betting odds, but intelligence may not be as inevitable.



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