Taxonomy

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From encyclopedia britannica: "in a broad sense, the science of classification, but more strictly the classification of living and extinct organisms—i.e., biological classification. The term is derived from the Greek taxis (“arrangement”) and nomos (“law”). Taxonomy is, therefore, the methodology and principles of systematic botany and zoology and sets up arrangements of the kinds of plants and animals…"

Also from britannica: In biology, the classification of organisms into a hierarchy of groupings, from the general to the particular, that reflect evolutionary and usually morphological relationships: kingdom, phylum, class, order, family, genus, species.

The black-capped chickadee, for example, is an animal (kingdom Animalia) with a dorsal nerve cord (phylum Chordata) and feathers (class Aves: birds) that perches (order Passeriformes: perching birds) and is small with a short bill (family Paridae), a song that sounds like “chik-a-dee” (genus Parus), and a black-capped head (species atricapillus). Most authorities recognize five kingdoms: monerans (prokaryotes), protists, fungi (see fungus), plants, and animals. Carolus Linnaeus established the scheme of using Latin generic and specific names in the mid-18th century; his work was extensively revised by later biologists.

Note also this from disambiguation page: Scientific classification is classification by means of science.

Biology

Taxonomy

• Scientific Classification is the naming method for naming and grouping organisms, which suceededs both the Linnaeus System and Aristotle's system, and is based on phylogeny, not just morphology
• Linnaean classification is the classical way of classifying organism
• Cladistics is the new way of classifying organisms, based solely on phylogeny
• Virus classification

Astronomy

• stellar classification
• galactic classification

Taxonomy (from Greek verb tassein = "to classify" and nomos = law, science, cf "economy") may refer to:

• the science of classification (see alpha taxonomy)
• a classification

Initially taxonomy was only the science of classifying living organisms, but later the word was applied in a wider sense, and may also refer to either a classification of things, or the principles underlying the classification. Almost anything, animate objects, inanimate objects, places, and events, may be classified according to some taxonomic scheme.

Taxonomy is a highly covered topic when discussing primates related to anthropology. There are many similarities that are between humans and apes that are evident in anatomy, brain structures, genetics, and biochemistry. The physical similarities between humans and apes are known as zoological taxonomy. Taxonomy is the organisms related to the resemblance of others. Take for instance humans and apes. "Humans and apes belong to the same taxonomic superfamily, hominoidea, also known as hominoids." Monkeys are not apart of this family, they are placed in two families known as ceboidea and cercopithecoidea."This means that humans and apes are more closely related to each other than either is to monkeys. Taxonomy also carries a subspecies category which would include the Neanderthals family. The comparison to the differences between monkey and humans would be the similar to the differences between homo sapiens and hominoids.

Taxonomies are frequently hierarchical in structure. However taxonomy may also refer to relationship schemes other than hierarchies, such as network structures. Other taxonomies may include single children with multi-parents, for example, "Car" might appear with both parents "Vehicle" and "Steel Mechanisms". A taxonomy might also be a simple organization of objects into groups, or even an alphabetical list. In current usage within "Knowledge Management", taxonomies are seen as slightly less broad than ontologies.

Mathematically, a hierarchical taxonomy is a tree structure of classifications for a given set of objects. At the top of this structure is a single classification, the root node, that applies to all objects. Nodes below this root are more specific classifications that apply to subsets of the total set of classified objects. So for instance in common schemes of scientific classification of organisms, the root is the Organism (as this applies to all living things, it is implied rather than stated explicitly). Below this are the Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species, with various other ranks sometimes inserted.

Some have argued that the human mind naturally organizes its knowledge of the world into such systems. This view is often based on the epistemology of Immanuel Kant. Anthropologists have observed that taxonomies are generally embedded in local cultural and social systems, and serve various social functions. Perhaps the most well-known and influential study of folk taxonomies is Émile Durkheim's The Elementary Forms of Religious Life. The theories of Kant and Durkheim also influenced Claude Lévi-Strauss, the founder of anthropological structuralism. Lévi-Strauss wrote two important books on taxonomies: Totemism and The Savage Mind.

Such taxonomies as those analyzed by Durkheim and Lévi-Strauss are sometimes called folk taxonomies to distinguish them from scientific taxonomies that claim to be disembedded from social relations and thus objective and universal.

A recent neologism, folksonomy, should not be confused with Folk Taxonomy (though it is obviously a contraction of the two words). Those who support scientific taxonomies have recently criticized folksonomies by dubbing them fauxonomies.

The phrase enterprise taxonomy is used in business to describe a very limited form of taxonomy used only within one organization.

The field of solving or best-fitting of numerical equations that characterize all measurable quantities of a set of objects is called cluster analysis; this is a form of taxonomy called numerical taxonomy or taximetrics.

See also

• systematics
• scientific classification
• ontology
• Folksonomy
• Celestial Emporium of Benevolent Recognition, a fictional Chinese encyclopedia with an "impossible" taxonomic scheme.
• Phylocode, a controversial method to revise the naming system developed by Linnaeus

Alpha Taxonomy — This Section is Taken from Alpha Taxonomy in Wikipedia

Taxonomy, sometimes alpha taxonomy, is the science of finding, describing and naming organisms, thus giving rise to taxa. The phrase arose as a means to distinguish the original meaning of the work "taxnomy" from its newer usages.

For a long time the term "taxonomy" was unambiguous, but over time the word "taxonomy" gained several other meanings and thus became confusing. To some extent it is being replaced, in its original (and narrow) meaning, by "alpha taxonomy". Another source of confusion is the relationship to systematics. The words "taxonomy" and "systematics" have a similar history and similar meanings: over time these have been used as synonyms, as overlapping or as completely complementary.

In today's usage, Taxonomy (as a science) deals with finding, describing and naming organisms, a science supported by institutions holding collections of these organisms, with relevant data, carefully curated: such instutes include Natural History Museums and Herbaria and Botanical Gardens. Systematics (as a science) deals with the relationships between taxa, especially at the higher levels, these days often based to a great extent on DNA from mitochondria and chloroplasts. The latter, sometimes known as molecular systematics, is doing well, likely at the expense of taxonomy (Wheeler, 2004).

Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. Modern classification has its roots in the system of Carolus Linnaeus, who grouped species according to shared physical characteristics. These groupings have been revised since Linnaeus to improve consistency with the Darwinian principle of common descent. Molecular systematics, which uses genomic DNA analysis, has driven many recent revisions and is likely to continue to do so. Scientific classification belongs to the science of taxonomy or biological systematics.

Modern developments

Whereas Linnaeus classified for ease of identification, it is now generally accepted that classification should reflect the Darwinian principle of common descent.

Since the 1960s a trend called cladistic taxonomy or cladism has emerged, arranging taxa in an evolutionary tree. If a taxon includes all the descendants of some ancestral form, it is called monophyletic, as opposed to paraphyletic. Other groups are called polyphyletic.

A new formal code of nomenclature, the PhyloCode, is currently under development, intended to deal with clades rather than taxa. It is unclear, should this be implemented, how the different codes will coexist.

Domains are a relatively new grouping. The three-domain system was first invented in 1990, but not generally accepted until later. Now, the majority of biologists accept the domain system, but a large minority use the five-kingdom method. One main characteristic of the three-domain method is the separation of Archaea and Bacteria, previously grouped into the single kingdom Bacteria (sometimes Monera). A small minority of scientists add Archaea as a sixth kingdom but do not accept the domain method.

Early systems

The earliest known system of classifying forms of life comes from the Greek philosopher Aristotle, who classified animals based on their means of transportation (air, land, or water).

In 1172 Ibn Rushd (Averroes), who was a judge (Qadi) in Seville, translated and abridged Aristotle's book de Anima (On the Soul) into Arabic. His original commentary is now lost, but its translation into Latin by Michael Scot survives.

An important advance was made by the Swiss professor, Conrad von Gesner (1516–1565). Gesner's work was a critical compilation of life known at the time.

The exploration of parts of the New World next brought to hand descriptions and specimens of many novel forms of animal life. In the latter part of the 16th century and the beginning of the 17th, careful study of animals commenced, which, directed first to familiar kinds, was gradually extended until it formed a sufficient body of knowledge to serve as an anatomical basis for classification. Advances in using this knowledge to classify living beings bear a debt to the research of medical anatomists, such as Fabricius (1537–1619), Petrus Severinus (1580–1656), William Harvey (1578–1657), and Edward Tyson (1649–1708). Advances in classification due to the work of entomologists and the first microscopists is due to the research of people like Marcello Malpighi (1628–1694), Jan Swammerdam (1637–1680), and Robert Hooke (1635–1702).Successive developments in the history of insect classification may be followed on the website [1]by clicking on succeeding works in chronological order.

John Ray (1627–1705) was an English naturalist who published important works on plants, animals, and natural theology. The approach he took to the classification of plants in his Historia Plantarum was an important step towards modern taxonomy. Ray rejected the system of dichotomous division by which species were classified according to a pre-conceived, either/or type system, and instead classified plants according to similarities and differences that emerged from observation.

Linnaeus

Two years after John Ray's death, Carolus Linnaeus (1707–1778) was born. His great work, the Systema Naturae, ran through twelve editions during his lifetime (1st ed. 1735). In this work nature was divided into three realms: mineral, vegetable and animal. Linnaeus used four ranks: class, order, genus, and species.

Linnaeus is best known for his introduction of the method still used to formulate the scientific name of every species. Before Linnaeus, long many-worded names had been used, but as these names gave a description of the species, they were not fixed. By consistently using a two-word Latin name — the genus name followed by the specific epithet — Linnaeus separated nomenclature from taxonomy. This convention for naming species is referred to as binomial nomenclature.

Today, nomenclature is regulated by Nomenclature Codes, which allows names divided into ranks: see rank (botany) and rank (zoology).

Examples

The usual classifications of five species follow: the fruit fly so familiar in genetics laboratories (Drosophila melanogaster), humans (Homo sapiens), the peas used by Gregor Mendel in his discovery of genetics (Pisum sativum), the fly agaric mushroom Amanita muscaria, and the bacterium Escherichia coli. The eight major ranks are given in bold; a selection of minor ranks are given as well.

Rank	Fruit fly	Human	Pea	Fly Agaric	E. coli
Domain	Eukarya	Eukarya	Eukarya	Eukarya	Bacteria
Kingdom	Animalia	Animalia	Plantae	Fungi	Monera
Phylum or Division	Arthropoda	Chordata	Magnoliophyta	Basidiomycota	Eubacteria
Subphylum or subdivision	Hexapoda	Vertebrata	Magnoliophytina	Hymenomycotina
Class	Insecta	Mammalia	Magnoliopsida	Homobasidiomycetae	Proteobacteria
Subclass	Pterygota	Placentalia	Magnoliidae	Hymenomycetes
Order	Diptera	Primates	Fabales	Agaricales	Enterobacteriales
Suborder	Brachycera	Haplorrhini	Fabineae	Agaricineae
Family	Drosophilidae	Hominidae	Fabaceae	Amanitaceae	Enterobacteriaceae
Subfamily	Drosophilinae	Homininae	Faboideae	Amanitoideae
Genus	Drosophila	Homo	Pisum	Amanita	Escherichia
Species	D. melanogaster	H. sapiens	P. sativum	A. muscaria	E. coli

Notes:

• Botanists and mycologists use systematic naming conventions for higher taxa, using the Latin stem of the type genus for that taxon, plus a standard ending (See below for a list of standard endings). For example, the rose family Rosaceae is named after the stem "Ros-" of the type genus Rosa plus the standard ending "-aceae" for a family.
• Zoologists use similar conventions for higher taxa, but only up to the rank of superfamily.
• Higher taxa and especially intermediate taxa are prone to revision as new information about relationships is discovered. For example, the traditional classification of primates (class Mammalia — subclass Theria — infraclass Eutheria — order Primates) is challenged by new classifications such as McKenna and Bell (class Mammalia — subclass Theriformes — infraclass Holotheria — order Primates). See mammal classification for a discussion. These differences arise because there are only a small number of ranks available and a large number of branching points in the fossil record.
• Within species further units may be recognised. Animals may be classified into subspecies (for example, Homo sapiens sapiens, modern humans). Plants may be classified into subspecies (for example, Pisum sativum subsp. sativum, the garden pea) or varieties (for example, Pisum sativum var. macrocarpon, snow pea), with cultivated plants getting a cultivar name (for example, Pisum sativum var. macrocarpon 'Snowbird'). Bacteria may be classified by strains (for example Escherichia coli O157:H7, a strain that can cause food poisoning).

Group suffixes

Taxa above the genus level are often given names derived from the Latin (or Latinized) stem of the type genus, plus a standard suffix. The suffixes used to form these names depend on the kingdom, and sometimes the phylum and class, as set out in the table below.

Rank	Plants	Algae	Fungi	Animals
Division/Phylum	-phyta		-mycota
Subdivision/Subphylum	-phytina		-mycotina
Class	-opsida	-phyceae	-mycetes
Subclass	-idae	-phycidae	-mycetidae
Superorder	-anae
Order	-ales
Suborder	-ineae
Infraorder	-aria
Superfamily	-acea			-oidea
Family	-aceae			-idae
Subfamily	-oideae			-inae
Tribe	-eae			-ini
Subtribe	-inae			-ina

Notes

• The stem of a word may not be straightforward to deduce from the nominative form as it appears in the name of the genus. For example, Latin "homo" (human) has stem "homin-", thus Hominidae, not "Homidae".
• For animals, there are standard suffixes for taxa only up to the rank of superfamily (ICZN article 27.2).

See also

• Binomial nomenclature
• Trinomial nomenclature
• Taxonomy
• International Code of Botanical Nomenclature
• International Code of Zoological Nomenclature
• List of chordate orders
• List of Latin and Greek words commonly used in systematic names
• Phylogenetic tree
• Virus classification

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