Level of life
Organism
An individual living thing, from a single bacterium to a tree or a person.
Archaea
Single-celled organisms without a nucleus that form a separate domain of life from bacteria.Source: Woese & Fox, 1977Source: Woese et al., 1990
Step 2 of 7ReadingOrganism or group
How Archaea connects
Archaea is an example of
Archaea is described by
Idea or model
Three domains of life
Comparing ribosomal RNA divides life into three domains: Bacteria, Archaea and Eukarya.
Archaea is related to
Organism or group
Thermophiles
Microbes that thrive in heat, such as Thermus aquaticus from hot springs, the source of a heat-stable enzyme used in PCR.
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Sources & further reading
The explanations on this page are our own summaries of these sources. Follow a link to read the original; if anything here disagrees with it, the original wins. How we choose and check sources.
Phylogenetic structure of the prokaryotic domain: the primary kingdoms (opens the original in a new tab)
Woese CR, Fox GE (1977). Proceedings of the National Academy of Sciences 74:5088-5090.
Ribosomal RNA comparisons revealed the archaea as a separate lineage.
Peer-reviewedPrimary researchTowards a natural system of organisms: proposal for the domains Archaea, Bacteria, and Eucarya (opens the original in a new tab)
Woese CR, Kandler O, Wheelis ML (1990). Proceedings of the National Academy of Sciences 87:4576-4579.
Peer-reviewedPerspective