Extremophile

Organisms capable of living in extreme environments

An extremophile (from Latin extremus 'extreme' and Ancient Greek φιλία (philía) 'love') is an organism that is able to live or even thrive in extreme environments, such as extreme temperature (hot or cold), pressure, radiation, salinity, or pH level. Extremophiles are mainly species of microorganisms – bacteria and chiefly archaea, but also include some eukaryotes such as some fungi, and tardigrades. Since the definition of an extreme environment is relative to an arbitrarily defined standard, often an anthropocentric one, these organisms can be considered ecologically dominant in the evolutionary history of the planet.

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