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Cyanobacteria

Diversity and Versatility, Clues to Life in Extreme Environments

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Book cover Algae and Cyanobacteria in Extreme Environments

Part of the book series: Cellular Origin, Life in Extreme Habitats and Astrobiology ((COLE,volume 11))

Bacteria have inhabited Earth for 3.8 billion years and life on our planet was microbial for 3.2 billion years (Schopf, 1994). During this long period, microorganisms have evolved an incredible diversity, although a major part of this diversity may have already existed in the Archean. Cyanobacteria and, hence, oxygenic photosynthesis evolved 2.7–2.2 billion years ago and had therefore ample time to diversify and adapt to newly evolving niches that emerged on Earth (Schopf et al., 2002; Blank, 2004; Tice and Lowe, 2004). Through the advent of oxygenic photosynthesis (Blankenship, 1992), cyanobacteria were responsible for the oxygenation of the Earth’s atmosphere (Buick, 1992), thereby allowing the evolution of plants and animals 0.6 billion years ago and eventually were shaping the present biosphere.

Cyanobacteria combine the fixation of CO2 and N2, the two most important biogeochemical processes on Earth. They are globally important primary producers and contribute greatly to the global nitrogen budget (Karl et al., 2002). Cyanobacteria are essential players in the Earth’s present and past ecosystems. For any understanding of the evolution of life and of the biogeochemical cycles on Earth, knowledge about the ecology and evolution of the cyanobacteria is a prerequisite.

Cyanobacteria colonized successfully almost any illuminated environment on Earth, many of which are considered to be hostile for life. Cyanobacteria play a prominent role in many of these extreme environments. This chapter attempts to find clues explaining the evolutionary and ecological success of cyanobacteria.

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  1. Netherlands Institute of Ecology, 140, 4400 YC, Yerseke, The Netherlands

    Lucas J. Stal Ph.D

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  1. The Hebrew University of Jerusalem, Mevo Hadas 20, 1132, 90435, Efrat, Israel

    Joseph Seckbach Ph.D

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Stal, L.J. (2007). Cyanobacteria. In: Seckbach, J. (eds) Algae and Cyanobacteria in Extreme Environments. Cellular Origin, Life in Extreme Habitats and Astrobiology, vol 11. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-6112-7_36

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