Linnaean taxonomy

Linnaean Taxonomy divides living things into a hierarchy, starting with domains or kingdoms and the further into phylum, class, order, family, genus and species. One way to remember the ordering is "King Phillip Came Over For Great Spaghetti". This is based closely on the scheme established by Carolus Linnaeus, but over time has changed to reflect different considerations about the relationships of living things; with the advent of evolution, it is generally encouraged that groups be monophyletic.

Originally Linnaeus had three kingdoms in his scheme, namely Plantae, Animalia and an additional group for minerals, which has since been abandoned. Since then various forms have been moved into three new kingdoms - Monera, for prokaryotes, Protista, for protozoans and algae, and Fungi. This scheme is still far from the phylogenetic ideal and the five kingdom view has largely been supplanted in modern taxonomic work by a division into three domains - Bacteria and Archaea, which contain the prokaryotes, and Eukaryota, comprising the remaining forms. This was precipitated by the discovery of the Archaea.

Linnaeas taxonomy requires creation of many more phyla than basic seven, and even them doesn't provide full information about evolutionary relations between species. To overcome this problems, cladistics was proposed as better way of classification.

See also evolutionary tree, which has some further subdivisions.

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