The Surprising Archaea: Discovering Another Domain of LifeAlthough they comprise one of the three fundamental branches of life, the Archaea were only recognized as a group about twenty years ago. This recognition was based on similarities between their RNA sequences, similarities all the more striking because of the diversity of archaeal lifestyles. They include microorganisms that live in boiling water, within the guts of animals, or in concentration brines. It is also evident that the Archaea diverged