Alternative taxonomical classifications are those which differ from the commonly accepted classifications in fundamental ways. One could say that every single classification system since Linnaeus has been alternative at some point, before it was either completely rejected, or accepted as the standard. The current trend seems to be to replace older systems which use paraphyletic or polyphyletic taxa with those with monophyletic groups. This is facilitated by the use of clades, which abandon the use of conventional taxa, such as kingdoms and phyla, and use instead monophyletic groups nested inside one another. A painting of Carolus Linnaeus Carl Linnaeus, also known after his ennoblement as Carl von Linné, and who wrote under the Latinized name Carolus Linnaeus (May 23, 1707 – January 10, 1778), was a Swedish scientist who laid the foundations for the modern scheme of taxonomy. ...

Historical alternative classifications

These are systems developed in the past that have been either ultimately rejected, or ultimately accepted by the scientific community. This article or section does not adequately cite its references or sources. ...

Linnaean taxonomy

Carolus Linnaeus, who created the first classification system, divided the known universe into three kingdoms: Animalia, Vegetabilia, and Mineralia. This system recognized the differences between the two most visible forms of life, plants and animals, and placed everything else (rocks, clouds, water, fire, etc.) in a catch-all category. This system was the standard for many years, and provided the basis for the "kingdom" taxon in all subsequent taxonomical systems. Carolus Linnaeus, also known after his ennoblement as  , (May 23, 1707[1] – January 10, 1778), was a Swedish botanist, physician and zoologist[2] who laid the foundations for the modern scheme of nomenclature. ... Phyla Subkingdom Parazoa Porifera (sponges) Subkingdom Agnotozoa Placozoa Orthonectida Rhombozoa Subkingdom Metazoa Radiata Cnidaria Ctenophora - Comb jellies Bilateria Protostomia Acoelomorpha Platyhelminthes - Flatworms Nemertina - Ribbon worms Gastrotricha Gnathostomulida - Jawed worms Micrognathozoa Rotifera - Rotifers Acanthocephala Priapulida Kinorhyncha Loricifera Entoprocta Nematoda - Roundworms Nematomorpha - Horsehair worms Cycliophora Mollusca - Mollusks Sipuncula - Peanut worms Annelida - Segmented... Divisions Green algae land plants (embryophytes) non-vascular embryophytes Hepatophyta - liverworts Anthocerophyta - hornworts Bryophyta - mosses vascular plants (tracheophytes) seedless vascular plants Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongue ferns seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta... Minerals are natural compounds formed through geological processes. ...

The five-kingdom system

An illustration of the five kingdom system

As scientific methods of experimentation improved, in particular with the use of the microscope, it became increasingly obvious that the world of life could not be divided simply into plant and animal kingdoms. Many microscopic organisms, or "animalcules" as they were called, did not fit well into either category. Therefore, the kingdom Protista (or Protoctista) was proposed by Ernst Haekel to comprise the unicellular organisms. It was not widely accepted at first, but it was the first step towards improving the Linnaean system. Image File history File links Download high-resolution version (840x1171, 848 KB) I (John Schmidt) made this diagram for Wikipedia using these images: Image:Arabidopsis thaliana. ... Image File history File links Download high-resolution version (840x1171, 848 KB) I (John Schmidt) made this diagram for Wikipedia using these images: Image:Arabidopsis thaliana. ... Typical phyla Rhodophyta (red algae) Chromista Heterokontophyta (heterokonts) Haptophyta Cryptophyta (cryptomonads) Alveolates Pyrrhophyta (dinoflagellates) Apicomplexa Ciliophora (ciliates) Excavates Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Amoebozoa Choanozoa Many others; classification varies The Kingdom Protista or Protoctista is one of the commonly recognized biological kingdoms, including all the eukaryotes except for...

The next problem with Linnaean taxonomy was the prokaryotic cell. Again, as methods of scientific research improved, it became apparent that there were two distinct types of cells - those of eukaryotes, and those of prokaryotes. Prokaryotes (pro-KAR-ee-oht) (from Old Greek pro- before + karyon nut or kernel, referring to the cell nucleus, + suffix -otos, pl. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Protista Alternative Phylogeny Unikonta    Opisthokonta    Amoebozoa Bikonta    Apusozoa    Cabozoa       Rhizaria       Excavata    Corticata       Archaeplastida       Chromalveolata Animals, plants, fungi, and protists are eukaryotes (IPA: ), organisms with a complex cell or cells, where the genetic material is organized into a membrane-bound nucleus or nuclei. ...