The (bit buzzwordy) name for organisms that live in 'extreme' conditions. Since this extremeness is only defined by what
we like it is somewhat relative. However, it is true to say that most types of
life live in mesophillic conditions of 30° Centigrade, low salt, low pressure environments. Some argue that large amounts of
biomass exist in the subsurface regions in the
deep hot biosphere, and some calculations suggest that
more life exists below the surface than on top (measured in terms of weight). Here are some types of extremophile:
When first encountered, some of these organisms helped to reconstruct the
classification system for life. Indeed, some have even used their abilities as justification for
extraterrestrial life, although not in the form of bug eyed aliens as such. Amazingly, some soil bacteria survived a long trip on a space probe - which suggests that
life could spread between planets.
Most of the known extremophiles are microorganisms, although there are a few exceptions, such as the larger plants and animals that live in the superheated waters near volcanic vents on the floors of the oceans.
See also: archaea and extremozyme.