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Water, Bacteria, Life on Mars, and Microbial Diversity

Water History and Culture

  1. David B. Vance1,
  2. James A. Jacobs2

Published Online: 15 JUL 2005

DOI: 10.1002/047147844X.wh1504

Water Encyclopedia

Water Encyclopedia

How to Cite

Vance, D. B. and Jacobs, J. A. 2005. Water, Bacteria, Life on Mars, and Microbial Diversity. Water Encyclopedia. 4:746–748.

Author Information

  1. 1

    ARCADIS, Midland, Texas

  2. 2

    Environmental Bio-Systems, Inc., Mill Valley, California

Publication History

  1. Published Online: 15 JUL 2005


Microbial life is extremely diverse with regard to ambient conditions, metabolic pathways, and geographic dispersion at depth in soils and sedimentary formations on Earth. Original bacterial life on Earth started in anaerobic conditions, without free oxygen in the atmosphere. Water chemistry in the primitive oceans would have been devoid of significant dissolved oxygen. The primitive atmosphere was chiefly carbon monoxide (CO), hydrogen sulfide (H2S), nitrogen (N2), hydrogen (H2), and water. Some of the more volatile trace elements such as chromium, manganese, and sodium may also have been present (1). Since that time, almost every niche on Earth has been colonized by some type of microbial life. Given the robust nature of microbial life on Earth, it is possible that microbial life existed on other planets having similar elements and compounds. As the very early history of Mars may have been somewhat similar to that of Earth, Mars may have had the conditions for microbial life. In the oceans, the gases in the primitive atmosphere were present as dissolved constituents. In addition, given the reducing conditions, soluble forms of reduced metals were also present, with ferrous iron likely being a dominant species.


  • acidophiles;
  • alkalophiles;
  • archaebacteria;
  • barotolerant;
  • denitrifiers;
  • eubacteria;
  • eukaryotes;
  • ferric iron reducers;
  • ferrous iron oxidizers;
  • halophiles;
  • hydrogen formers;
  • mars;
  • metabolic pathways;
  • methanogens;
  • microbial life;
  • multicellular life;
  • nitrate reducers;
  • primitive earth atmosphere;
  • sulfate reducers;
  • sulfide oxidizers;
  • thermophiles