Archaebacteria, or simply Archaea, are single-celled, complex prokaryotic organisms, according to the University of California Museum of Paleontology. Archaebacteria is a misnomer because these organisms have a different genetic makeup from bacteria.
Comprising a separate domain from the Eukarya and Bacteria, Archaea have no nucleus, reproduce by binary fission, do not perform photosynthesis and do not produce spores. They can swim by using their flagella. Archaea live in a variety of conditions and environments, including the hot and molten areas of the deep seas, inside geysers and in the polar seas. Considered extremophiles, Archaea can live in temperatures exceeding 212 degrees Fahrenheit. Some forms of Archaea live in sewers, soil and in marshes, states the Encyclopedia of Life. Archaea make up approximately 20 percent of Earth's biomass, but most Archaea have not been studied.
Archaea were first discovered in the late 1970s when scientists found a group of organisms with different DNA sequences from bacteria and eukaryotes. Some Archaea were found in the hot springs of Yellowstone National Park, according to class notes from Rhode Island College. Carl Woese, a microbiologist, first suggested the separation between Archaea, Eubacteria and Eukarya, but the separation did not occur until 1977 when genetic coding allowed scientists to determine the genetic differences between organisms, explains the Encyclopedia of Life.