A genus (, genera) is a taxonomic rank used in the biological classification of living and fossil organisms in biology. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus.E.G., Felis catus and Felis silvestris are two species within the genus Felis. Felis is a genus within the family Felidae.
The composition of a genus is determined by a taxonomist. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful:
- monophyly – all descendants of an ancestral taxon are grouped together (i.e. phylogenetic analysis should clearly demonstrate both monophyly and validity as a separate lineage ).
- reasonable compactness – a genus should not be expanded needlessly; and
- distinctness – with respect to evolutionarily relevant criteria, i.e. ecology, morphology, or biogeography; note that DNA sequences are a consequence rather than a condition of diverging evolutionary lineages except in cases where they directly inhibit gene flow (e.g. postzygotic barriers).
Moreover, genera should be composed of phylogenetic units of the same kind as other (analogous) genera.
In mathematics, genus (plural genera) has a few different, but closely related, meanings:
Genus (Gr.: γένος [genos], pl. γένη [genē], lat. genus, pl. genera "type, kind") is a term used in the Ancient Greek and Roman theory of music to describe certain classes of intonations of the two movable notes within a tetrachord.
Aristoxenus (in his fragmentary treatise on rhythm) names 'genera' some patterns of rhythm. The tetrachordal concept is also found in the modal theory of Byzantine music and relates to the jins of Arabic music.
Genus is a furry erotic comic book originally published by Antarctic Press and continued by Radio Comix under its "Sin Factory" imprint. Issues contain sexually explicit stories and pin-up illustrations by various artists, featuring anthropomorphic animals (no human characters are included), and are labeled for sale to adults only. The series began in June 1993, with 94 issues published as of April 2012. Originally published in stapled format, recent issues are square bound with higher page counts. Diamond Comic Distributors' catalog describes it as "The longest-running erotic comic anthology".
Genus, from the Latin genus, generis "birth, race, stock, kind" may refer to:
- In Linnaean taxonomy, genus is the rank between family and species.
- Genus (journal), a journal of population genetics
Genus (mathematics), a classifying property of a mathematical object
- Genus of a multiplicative sequence
- Geometric genus
- In graph embedding, the genus of the graph is the genus of the surface in which it can be embedded
- In the theory of numerical semigroups, the genus of a numerical semigroup is the cardinality of the set of gaps in the numerical semigroup
- grammatical gender
- Genus (music), a concept in ancient Greek music theory
- Genus (philosophy)
- Genus (linguistics)
in popular culture:
- Genus (comic book), a furry erotic comic book
- In Alienators: Evolution Continues, the Genus are monstrous alien organisms that have a high speed evolution
- Genus plc, a British biotechnology company
- Genus Limited, video and photographic accessories company
- Sport Club Genus de Porto Velho, a Brazilian football (soccer) club
In Scholastic logic a Genus is one of the Predicables. Genus is that part of a definition which is also predicable of other things different from the definiendum. A triangle is a rectilineal figure; i.e. in fixing the genus of a thing, we subsume it under a higher universal, of which it is a species.
In linguistics, a genus is a group of phylogenetically related languages inside a linguistic family, in particular a genus is a group languages which can be recognized as related languages without using complex methods of historical linguistics. The notion of genus was proposed by M. Dryer., and is used commonly in some academic projects such as: WALS. According to WALS most families can be subdivided in a certain number of genus, so the notion is similar to the term subfamily.
n. a general kind of something; "ignore the genus communism"
(biology) taxonomic group containing one or more species
[also: genera (pl)]
The Collaborative International Dictionary
Genus \Ge"nus\ (j[=e]"n[u^]s), n.; pl. Genera. [L., birth, race, kind, sort; akin to Gr. ?. See Gender, and cf. Benign.]
(Logic) A class of objects divided into several subordinate species; a class more extensive than a species; a precisely defined and exactly divided class; one of the five predicable conceptions, or sorts of terms.
(Biol.) An assemblage of species, having so many fundamental points of structure in common, that in the judgment of competent scientists, they may receive a common substantive name. A genus is not necessarily the lowest definable group of species, for it may often be divided into several subgenera. In proportion as its definition is exact, it is natural genus; if its definition can not be made clear, it is more or less an artificial genus.
Note: Thus in the animal kingdom the lion, leopard, tiger, cat, and panther are species of the Cat kind or genus, while in the vegetable kingdom all the species of oak form a single genus. Some genera are represented by a multitude of species, as Solanum (Nightshade) and Carex (Sedge), others by few, and some by only one known species.
Subaltern genus (Logic), a genus which may be a species of a higher genus, as the genus denoted by quadruped, which is also a species of mammal.
Summum genus [L.] (Logic), the highest genus; a genus which can not be classed as a species, as being.
Douglas Harper's Etymology Dictionary
(plural genera), 1550s as a term of logic, "kind or class of things" (biological sense dates from c.1600), from Latin genus (genitive generis) "race, stock, kind; family, birth, descent, origin," cognate with Greek genos "race, kind," and gonos "birth, offspring, stock," from PIE root *gene- "produce, give birth, beget," with derivatives referring to family and tribal groups (cognates: Sanskrit janati "begets, bears," janah "race," janman- "birth, origin," jatah "born;" Avestan zizanenti "they bear;" Greek gignesthai "to become, happen;" Latin gignere "to beget," gnasci "to be born," genius "procreative divinity, inborn tutelary spirit, innate quality," ingenium "inborn character," germen "shoot, bud, embryo, germ;" Lithuanian gentis "kinsmen;" Gothic kuni "race;" Old English cennan "beget, create;" Old High German kind "child;" Old Irish ro-genar "I was born;" Welsh geni "to be born;" Armenian chanim "I bear, I am born").
Longman Dictionary of Contemporary English
n. 1 (context biology taxonomy English) a rank in the classification of organisms, below family and above species; a taxon at that rank 2 A group with common attributes. 3 (context topology English) A number measuring some aspect of the complexity of any of various manifolds or graphs 4 (context semantics English) Within a definition, a broader category of the defined concept.
Usage examples of "genus".
But even admitting this derivation from a unity--a unity however not predicated of them in respect of their essential being--there is, surely, no reason why each of these Existents, distinct in character from every other, should not in itself stand as a separate genus.
The forest trees are almost solely the Ailanthus glandulosus and the Zelkowa keaki, often matted together with a white-flowered trailer of the Hydrangea genus.
Xylomelum pyriforme or native pear trees with their wooden fruit and unpleasant odour, and the Goodenia ovata with its dark serrated leaves and yellow flowers and the Pittosporum and Sassafras were all clasped together and held close by native jasmine, and up through it all the cabbage and bangalow palms and the Eucalyptus microcorys or tallow wood and the Swamp Mahogany or robusta of the eucalyptus genus stood into the humid air.
We may instance Rubus, Rosa, and Hieracium amongst plants, several genera of insects, and several genera of Brachiopod shells.
Genera which are polymorphic in one country seem to be, with some few exceptions, polymorphic in other countries, and likewise, judging from Brachiopod shells, at former periods of time.
Even with lichens removed, bryophytes is a busy realm, with over ten thousand species contained within some seven hundred genera.
In the Classical age - Locke and Linnaeus, Buffon and Hume are our evidence of this - the critical question concerned the basis for resemblance and the existence of the genus.
Why not bisect the unity, Motion, and so make Action and Passion two species of the one thing, ceasing to consider Action and Passion as two genera?
Conditions necessary for these movements--List of Genera and Families, which include sleeping plants--Description of the movements in the several Genera--Oxalis: leaflets folded at night--Averrhoa: rapid movements of the leaflets--Porlieria: leaflets close when plant kept very dry--Tropaeolum: leaves do not sleep unless well illuminated during day--Lupinus: various modes of sleeping--Melilotus: singular movements of terminal leaflet--Trifolium--Desmodium: rudimentary lateral leaflets, movements of, not developed on young plants, state of their pulvini--Cassia: complex movements of the leaflets--Bauhinia: leaves folded at night--Mimosa pudica: compounded movements of leaves, effect of darkness--Mimosa albida, reduced leaflets of--Schrankia: downward movement of the pinnae--Marsilea: the only cryptogam known to sleep--Concluding remarks and summary--Nyctitropism consists of modified circumnutation, regulated by the alternations of light and darkness--Shape of first true leaves.
Brassica oleracea, circumnutation of the radicle, of the arched hypocotyl whilst still buried beneath the ground, whilst rising above the ground and straightening itself, and when erect--Circumnutation of the cotyledons--Rate of movement--Analogous observations on various organs in species of Githago, Gossypium, Oxalis, Tropaeolum, Citrus, Aesculus, of several Leguminous and Cucurbitaceous genera, Opuntia, Helianthus, Primula, Cyclamen, Stapelia, Cerinthe, Nolana, Solanum, Beta, Ricinus, Quercus, Corylus, Pinus, Cycas, Canna, Allium, Asparagus, Phalaris, Zea, Avena, Nephrodium, and Selaginella.
It is a rule of wide generality, that whenever there is any difference in the degree of exposure to radiation between the upper and the lower surfaces of leaves and leaflets, it is the upper which is the least exposed, as may be seen in Lotus, Cytisus, Trifolium, and other genera.
In these two genera the elaters are attached to a sterile group of cells projecting into the upper end of the capsule, and on dehiscence remain connected with the tips of the valves.
As for the differentia being derived from the same genus as themselves, namely, Quality, and from no other genus, if we proceed on the principle that virtue is bound up with pleasure, vice with lust, virtue again with the acquisition of food, vice with idle extravagance, and accept these definitions as satisfactory, then clearly we have, here too, differentiae which are not qualities.
It remains to decide whether there can be any differentia derived from the genus to which the differentiated thing belongs, or whether it must of necessity belong to another genus?
Surely not: the differentiae must come from outside the genus differentiated: they must be differentiae of Being proper, but cannot be identical with it.