In some systems of scientific classification, Biota, Vitae, Eobionti is the superdomain that classifies all life. For that reason it is often disputed how the taxon should be further divided, as the definition of "what life really is" is often changed or adjusted, and also if extraterrestrial life would be included besides the life on Earth, if extraterrestrial life is discovered. In general, all cellular life is naturally included in the Biota; when there is mention of non-cellular life the taxon Biota is most often simply divided into Cytota (cellular life) and Acytota (non-cellular life).