RUSSIAN JOURNAL OF EARTH SCIENCES VOL. 10, ES1006, doi:10.2205/2007ES000252, 2008
Ancient biosphere: The origin, trends and eventsM. A. Fedonkin Paleontological Institute, Russian Academy of Sciences, Moscow, Russia
 The biogenesis in the electron-rich conditions of the Hadean Earth was, probably, inevitable due to the energy flow as a powerful factor of dynamic ordering of the molecular structures. Hydrogen as a primary fuel of life and the metal catalysts, in particular, tungsten, iron and nickel, played a crucial role in the initiation of life. However the physical-chemical parameters of biosphere departed form the initial ones. Subsequent biological evolution was driven in a great degree by competition for access to hydrogen from the primary sources such as the degassing of the Earth interior or radiolysis, and from the simple hydrogen compounds via splitting the molecules of CH4, NH3, H2S, and at last, H2O in the oxygenic photosynthesis. The archaic metabolic pathways in the cell were superimposed by the new metabolic modules that have been formed due to the interaction with new environmental factors. This process and compartmentalization of the ancient biochemistry in vesicles and organelles etc. were resulted in the growing complexity of the cell. Symbiogenesis based on syntrophy, mutual dependence on the waste products of each other, was a key factor of early eukaryotization of the cell and of the biodiversity growth. Multidisciplinary synthesis of data reveals the timing of the most important events in early biosphere such as the earliest activity of the methanogens, origins of oxygenic photosynthesis, eukaryotic cell, and multicellular animals. New types of physiology related to those evolutionary events strongly affected the global biogeochemical cycles, sedimentogenesis and climate.
Received 28 January 2008; accepted 18 February 2008; published 4 March 2008.
Keywords: origin of life, hydrogen, metal biocatalysts, Hadean, Archaean, Proterozoic, prokaryotes, eukaryotes, metazoans.
Index Terms: 0410 Biogeosciences: Biodiversity; 0414 Biogeosciences: Biogeochemical cycles, processes, and modeling; 0444 Biogeosciences: Evolutionary geobiology; 0461 Biogeosciences: Metals; 9622 Information Related to Geologic Time: Proterozoic; 9623 Information Related to Geologic Time: Archean.
Citation: (2008), Ancient biosphere: The origin, trends and events, Russ. J. Earth Sci., 10, ES1006, doi:10.2205/2007ES000252.
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