Editing Life (section)

=== Linnaean ===

In the late 1740s, [[Carl Linnaeus]] introduced his system of [[binomial nomenclature]] for the classification of species. Linnaeus attempted to improve the composition and reduce the length of the previously used many-worded names by abolishing unnecessary rhetoric, introducing new descriptive terms and precisely defining their meaning.<ref>{{Cite journal |author1-last=Knapp |author1-first=Sandra |author1-link=Sandra Knapp |author2-last=Lamas |author2-first=Gerardo |author3-last=Lughadha |author3-first=Eimear Nic |author4-last=Novarino |author4-first=Gianfranco |title=Stability or stasis in the names of organisms: the evolving codes of nomenclature |journal=[[Philosophical Transactions of the Royal Society of London B]] |volume=359 |issue=1444 |pages=611–622 |date=April 2004 |pmid=15253348 |pmc=1693349 |doi=10.1098/rstb.2003.1445}}</ref>

The fungi were originally treated as plants. For a short period Linnaeus had classified them in the taxon [[Vermes]] in Animalia, but later placed them back in Plantae. [[Herbert Copeland (biologist)|Herbert Copeland]] classified the Fungi in his [[Protoctista]], including them with single-celled organisms and thus partially avoiding the problem but acknowledging their special status.<ref>{{Cite journal |title=The Kingdoms of Organisms |journal=Quarterly Review of Biology |volume=13 |issue=4 |doi=10.1086/394568 |year=1938 |page=383 | last1 = Copeland | first1 = Herbert F.|s2cid=84634277 }}</ref> The problem was eventually solved by [[Robert Whittaker (ecologist)|Whittaker]], when he gave them their own [[Kingdom (biology)|kingdom]] in his [[five-kingdom system]]. [[Evolutionary history]] shows that the fungi are more closely related to animals than to plants.<ref>{{Cite journal |last1=Whittaker |first1=R.H. |title=New concepts of kingdoms or organisms. Evolutionary relations are better represented by new classifications than by the traditional two kingdoms |journal=Science |volume=163 |issue=3863 |pages=150–160 |date=January 1969 |pmid=5762760 |doi=10.1126/science.163.3863.150 |bibcode=1969Sci...163..150W |citeseerx=10.1.1.403.5430}}</ref>

As advances in [[microscopy]] enabled detailed study of [[cell (biology)|cells]] and microorganisms, new groups of life were revealed, and the fields of [[cell biology]] and [[microbiology]] were created. These new organisms were originally described separately in [[protozoa]] as animals and [[thallophyte|protophyta/thallophyta]] as plants, but were united by [[Ernst Haeckel]] in the kingdom [[Protista]]; later, the [[prokaryote]]s were split off in the kingdom [[Monera]], which would eventually be divided into two separate groups, the Bacteria and the [[Archaea]]. This led to the [[six-kingdom system]] and eventually to the current [[three-domain system]], which is based on evolutionary relationships.<ref name="Woese1990"/> However, the classification of eukaryotes, especially of protists, is still controversial.<ref name="Adl 05">{{Cite journal |last1=Adl |first1=S.M. |last2=Simpson |first2=A.G. |last3=Farmer |first3=M.A. |title=The new higher level classification of eukaryotes with emphasis on the taxonomy of protists |journal=Journal of Eukaryotic Microbiology |volume=52 |issue=5 |pages=399–451 |year=2005 |pmid=16248873 |doi=10.1111/j.1550-7408.2005.00053.x|s2cid=8060916 |doi-access=free }}</ref>

As microbiology developed, viruses, which are non-cellular, were discovered. Whether these are considered alive has been a matter of debate; viruses lack characteristics of life such as cell membranes, metabolism and the ability to grow or respond to their environments. Viruses have been classed into "species" based on their [[genetics]], but many aspects of such a classification remain controversial.<ref>{{Cite journal |last=Van Regenmortel |first=M.H. |title=Virus species and virus identification: past and current controversies |journal=Infection, Genetics and Evolution |volume=7 |issue=1 |pages=133–144 |date=January 2007 |pmid=16713373 |doi=10.1016/j.meegid.2006.04.002|bibcode=2007InfGE...7..133V |s2cid=86179057 }}</ref>

The original Linnaean system has been modified many times, for example as follows:<!--the table is potentially highly misleading: it is not the case that Cavalier-Smith represents the latest thinking and indeed his classification of the Eukaryotes is not widely accepted-->

{{Biological systems}}

The attempt to organise the Eukaryotes into a small number of kingdoms has been challenged. The Protozoa do not form a [[clade]] or natural grouping<!--i.e. they're polyphyletic or paraphyletic-->,<ref name="SimpsonRoger2004">{{cite journal |title=The real 'kingdoms' of eukaryotes |last1=Simpson |first1=Alastair G.B. |last2=Roger |first2=Andrew J. |journal=[[Current Biology]] |volume=14 |issue=17 |pages=R693–R696 |doi=10.1016/j.cub.2004.08.038 |pmid=15341755|year=2004 |s2cid=207051421 |doi-access=free|bibcode=2004CBio...14.R693S }}</ref> and nor do the [[Chromista]] (Chromalveolata).<ref>{{cite journal |last1=Harper |first1=J.T. |last2=Waanders |first2=E. |last3=Keeling |first3=P.J. |year=2005 |title=On the monophyly of chromalveolates using a six-protein phylogeny of eukaryotes |journal=[[International Journal of Systematic and Evolutionary Microbiology]] |volume=55 |issue=Pt 1 |pmid=15653923 |pages=487–496 |doi=10.1099/ijs.0.63216-0  |doi-access=free}}</ref>