the hard, variously colored, calcareous skeleton secreted by certain marine polyps. 2. such skeletons collectively, forming reefs, islands, etc. 3. the solitary or colonial polyp that secretes this calcareous skeleton.
Ancient methanogens are the source of natural gas. Halophiles are bacteria that thrive in high salt concentrations such as those found in salt lakes or pools of sea water. Thermophiles are the heat-loving bacteria found near hydrothermal vents and hot springs.
archaebacteria belong to the domain archaea and are single celled organisms that tend to live in extreme environments like hot springs or in high salt regions in fact these organisms boldly go where others cannot they have been called extremophiles which means lover of extremes