Methanococcus lives near volcanic vents in the depths of the ocean where the temperature is near boiling. This archaebacterian is one of many others that live in extreme conditions and represent a group of organisms that differs greatly in many respects from eubacterians and the groups of eukaryotic organisms. With the first genome sequencing in the kingdom Archaebacteria completed, researchers can now compare the sequence to those genome sequences which have been obtained from other kingdoms of life. These comparisons may provide clues to the characteristics of life's first ancestor and to the patterns of the evolution of life forms.
Source: "Scientists Discover a Clue to the Origin of Life in a Microbe Rather Than a Myth" by Nicholas Wade, The New York Times, August 23, 1996