Legion (taxonomy)

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Legion %28taxonomy%29 LifeDomainKingdomPhylumClassOrderFamilyGenusSpecies
The hierarchy of biological classification's eight major taxonomic ranks. Intermediate minor rankings are not shown.

The legion, in biological classification, is a non-obligatory taxonomic rank within the Linnaean hierarchy sometimes used in zoology.

Taxonomic rank Level in a taxonomic hierarchy

In biological classification, taxonomic rank is the relative level of a group of organisms in a taxonomic hierarchy. Examples of taxonomic ranks are species, genus, family, order, class, phylum, kingdom, domain, etc.

Linnaean taxonomy A rank based classification system for organisms

Linnaean taxonomy can mean either of two related concepts:

  1. the particular form of biological classification (taxonomy) set up by Carl Linnaeus, as set forth in his Systema Naturae (1735) and subsequent works. In the taxonomy of Linnaeus there are three kingdoms, divided into classes, and they, in turn, into orders, genera, and species, with an additional rank lower than species.
  2. a term for rank-based classification of organisms, in general. That is, taxonomy in the traditional sense of the word: rank-based scientific classification. This term is especially used as opposed to cladistic systematics, which groups organisms into clades. It is attributed to Linnaeus, although he neither invented the concept of ranked classification nor gave it its present form. In fact, it does not have an exact present form, as "Linnaean taxonomy" as such does not really exist: it is a collective (abstracting) term for what actually are several separate fields, which use similar approaches.

Zoology is the branch of biology that studies the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. The term is derived from Ancient Greek ζῷον, zōion, i.e. "animal" and λόγος, logos, i.e. "knowledge, study".

Contents

Taxonomic rank

In zoological taxonomy, the legion is:

  1. subordinate to the class
  2. superordinate to the cohort.
  3. consists of a group of related orders

Legions may be grouped into superlegions or subdivided into sublegions, and these again into infralegions.

Use in zoology

Legions and their super/sub/infra groups have been employed in some classifications of birds and mammals. Full use is made of all of these (along with cohorts and supercohorts) in, for example, McKenna and Bell's classification of mammals. [1]

See also

Related Research Articles

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Taxonomy (biology) The science of identifying, describing, defining and naming groups of biological organisms

In biology, taxonomy is the science of defining and naming groups of biological organisms on the basis of shared characteristics. Organisms are grouped together into taxa and these groups are given a taxonomic rank; groups of a given rank can be aggregated to form a super-group of higher rank, thus creating a taxonomic hierarchy. The principal ranks in modern use are domain, kingdom, phylum, class, order, family, genus, and species. The Swedish botanist Carl Linnaeus is regarded as the founder of the current system of taxonomy, as he developed a system known as Linnaean taxonomy for categorizing organisms and binomial nomenclature for naming organisms.

In biological classification, the order is

  1. a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family. An immediately higher rank, superorder, may be added directly above order, while suborder would be a lower rank.
  2. a taxonomic unit, a taxon, in that rank. In that case the plural is orders.
Taeniolabidoidea superfamily of mammals (fossil)

Taeniolabidoidea is a group of extinct mammals known from North America and Asia. They were the largest members of the extinct order Multituberculata, as well as the largest non-therian mammals. Lambdopsalis even provides direct fossil evidence of mammalian fur in a fairly good state of preservation for a 60-million-year-old animal. Some of these animals were large for their time; Taeniolabis taoensis is the largest known multituberculate and though smaller, Yubaatar is the largest known Mesozoic Asian multituberculate. Average members of the Taeniolaboidea were about beaver-sized and the largest even reached sizes comparable to the largest beavers like Castoroides, up to about 100 kilograms.

Prototheria subclass of mammals

Prototheria is the subclass to which the orders Monotremata, Morganucodonta, Docodonta, Triconodonta and Multituberculata formerly belong.

Theria supercohort of mammals

Theria is a subclass of mammals amongst the Theriiformes. Theria includes the eutherians and the metatherians.

Mammal classification

Mammalia is a class of animal within the Phylum Chordata. Mammal classification has been through several iterations since Carl Linnaeus initially defined the class. No classification system is universally accepted; McKenna & Bell (1997) and Wilson & Reader (2005) provide useful recent compendiums. Many earlier ideas from Linnaeus et al. have been completely abandoned by modern taxonomists, among these are the idea that bats are related to birds or that humans represent a group outside of other living things. Competing ideas about the relationships of mammal orders do persist and are currently in development. Most significantly in recent years, cladistic thinking has led to an effort to ensure that all taxonomic designations represent monophyletic groups. The field has also seen a recent surge in interest and modification due to the results of molecular phylogenetics.

<i>Systema Naturae</i> major work by Carolus Linnaeus

Systema Naturae is one of the major works of the Swedish botanist, zoologist and physician Carl Linnaeus (1707–1778) and introduced the Linnaean taxonomy. Although the system, now known as binomial nomenclature, was partially developed by the Bauhin brothers, Gaspard and Johann, 200 years earlier, Linnaeus was first to use it consistently throughout his book. The first edition was published in 1735. The full title of the 10th edition (1758), which was the most important one, was Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis or translated: "System of nature through the three kingdoms of nature, according to classes, orders, genera and species, with characters, differences, synonyms, places".

Theriiformes is a subclass of mammals. The term was coined in 1997 by McKenna & Bell in their classification of mammals. In the strict sense, it is defined as all mammals more closely related to therians than to monotremes.

Zatheria sublegion of mammals

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Bristle-spined rat species of mammal

The bristle-spined rat is an arboreal rodent from Brazil. Also known as the bristle-spined porcupine or thin-spined porcupine, it is the only member of the genus Chaetomys and the subfamily Chaetomyinae. It was officially described in 1818, but rarely sighted since, until December 1986, when two specimens - one a pregnant female - were found in the vicinity of Valencia in Bahia.

Castorimorpha suborder of mammals

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Eocardiidae family of mammals

The Eocardiidae are an extinct family of caviomorph rodents from South America. The family is probably ancestral to the living family Caviidae, which includes cavies, maras, and capybaras and their relatives. McKenna and Bell (1997) divided eocardiids into two subfamilies, Luantinae for two of the oldest genera and Eocardiinae for remaining genera. Kramarz (2006) has recommended the abandonment of these subfamilies, as the genera placed in Luantinae appear to represent basal eocardiids, rather than a specialized side branch. The latter hypothesis had been proposed by Wood and Patterson (1959).

Suinae subfamily of mammals

Suinae is a subfamily of artiodactyl mammals that includes several of the extant members of Suidae and their closest relatives—the domestic pig and related species, such as babirusas. Several extinct species within the Suidae are classified in subfamilies other than Suinae. However, the classification of the extinct members of the Suoidea-the larger group that includes the Suidae, the peccary family (Tayassuidae), and related extinct species—is controversial, and different classifications vary in the number of subfamilies within Suidae and their contents. Some classifications, such as the one proposed by paleontologist Jan van der Made in 2010, even exclude from Suinae some extant taxa of Suidae, placing these excluded taxa in other subfamilies.

Isotemnidae family of mammals

Isotemnidae is an extinct family of notoungulate mammals known from the Paleocene to Middle Miocene of South America.

Cladotheria legion of mammals

Cladotheria is a group (legion) of mammals that includes the ancestor of Dryolestoidea, Peramuridae and Zatheria.

Neogene of the Old World is a database containing information about Eurasian Miocene to Pleistocene land mammal taxa and localities, with emphasis on the European Miocene and Pliocene.

Holotheria infraclass of mammals

Holotheria are a diverse group of mammals that are descendants of the last common ancestor of Kuehneotherium and Theria.

References

  1. McKenna, Malcolm C. and Susan K. Bell (editors). 1997. Classification of Mammals Above the Species Level. New York: Columbia University Press. ISBN   0-231-11013-8