Microbial life and biogeochemical cycling on land 3,220 million years ago

  title={Microbial life and biogeochemical cycling on land 3,220 million years ago},
  author={M. Homann and Pierre Sansjofre and Mark A. van Zuilen and C. Heubeck and Jianmin Gong and Bryan A Killingsworth and Ian S. Foster and Alessandro Airo and Martin J. Van Kranendonk and Magali Ader and Stefan V. Lalonde},
  journal={Nature Geoscience},
The colonization of emergent continental landmass by microbial life was an evolutionary step of paramount importance in Earth history. Here we report direct fossil evidence for life on land 3,220 million years ago (Ma) in the form of terrestrial microbial mats draping fluvial conglomerates and gravelly sandstones of the Moodies Group, South Africa. Combined field, petrographic, carbon isotope and Raman spectroscopic analyses confirm the synsedimentary origin and biogenicity of these unique… 

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