Species Wiki - What is the species?

In biology, a species is the basic unit of classification and a taxonomic rank, as well as a unit of biodiversity, but it has proven difficult to find a satisfactory definition. Scientists and conservationists need a species definition which allows them to work, regardless of the theoretical difficulties. If as Carl Linnaeus thought, species were fixed and clearly distinct from one another, there would be no problem, but evolutionary processes cause species to change continually, and to grade into one another. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. While this definition is often adequate, when looked at more closely it is problematic. For example, with hybridisation, in a species complex of hundreds of similar microspecies, or in a ring species, the boundaries between closely related species become unclear. Among organisms that reproduce only asexually, the concept of a reproductive species breaks down, and each clone is potentially a microspecies. Problems also arise when dealing with fossils, since reproduction cannot be examined; the concept of the chronospecies is therefore used in palaeontology. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. All species are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes in zoological nomenclature). For example, Boa constrictor is one of four species of the genus Boa. Species were seen from the time of Aristotle until the 18th century as fixed kinds that could be arranged in a hierarchy, the great chain of being. In the 19th century, biologists grasped that species could evolve given sufficient time. Charles Darwin's 1859 book The Origin of Species explained how species could arise by natural selection. That understanding was greatly extended in the 20th century through genetics and population ecology. Genetic variability arises from mutations and recombination, while organisms themselves are mobile, leading to geographical isolation and genetic drift with varying selection pressures. Genes can sometimes be exchanged between species by horizontal gene transfer; new species can arise rapidly through hybridisation and polyploidy; and species may become extinct for a variety of reasons. Viruses are a special case, driven by a balance of mutation and selection, and can be treated as quasispecies. As a practical matter, species concepts may be used to define species that are then used to measure biodiversity, though whether this is a good measure is disputed, as other measures are possible..

What does the word species mean? Find synonyms, antonyms and the meaning of the word species in our free online dictionary! Find words starting with species and anagrams of species.

Definitions of "species"

  • Biology A fundamental category of taxonomic classification, ranking below a genus or subgenus and consisting of related organisms capable of interbreeding. See Table at taxonomy. noun
  • Biology An organism belonging to such a category, represented in binomial nomenclature by an uncapitalized Latin adjective or noun following a capitalized genus name, as in Ananas comosus, the pineapple, and Equus caballus, the horse. noun
  • Logic A class of individuals or objects grouped by virtue of their common attributes and assigned a common name; a division subordinate to a genus. noun
  • A kind, variety, or type: "No species of performing artist is as self-critical as a dancer” ( Susan Sontag). noun
  • The human race; humankind. noun
  • Roman Catholic Church The outward appearance or form of the Eucharistic elements that is retained after their consecration. noun
  • Roman Catholic Church Either of the consecrated elements of the Eucharist. noun
  • Obsolete An outward form or appearance. noun
  • Obsolete Specie. noun
  • A type or kind of thing. noun
  • A group of plants or animals having similar appearance. noun
  • A rank in the classification of organisms, below genus and above subspecies; a taxon at that rank noun
  • A mineral with a unique chemical formula whose crystals belong to a unique crystallographic system. noun
  • The image of something cast on a surface, or reflected from a surface, or refracted through a lens or telescope; a reflection. noun
  • Either of the two elements of the Eucharist after they have been consecrated, so named because they retain the image of the bread and wine before their transubstantiation into the body and blood of Christ. noun
  • Visible or sensible presentation; appearance; a sensible percept received by the imagination; an image. noun
  • A group of individuals agreeing in common attributes, and designated by a common name; a conception subordinated to another conception, called a genus, or generic conception, from which it differs in containing or comprehending more attributes, and extending to fewer individuals. Thus, man is a species, under animal as a genus; and man, in its turn, may be regarded as a genus with respect to European, American, or the like, as species. noun
  • In science, a more or less permanent group of existing things or beings, associated according to attributes, or properties determined by scientific observation. noun
  • A sort; a kind; a variety noun

The word "species" in example sentences

A change of conditions occurs which threatens the existence of the species, but the _two varieties_ are adapted to the changing conditions, and, if accumulated, will form two new _species adapted to the new conditions_.. [Alfred Russel Wallace: Letters and Reminiscences, Vol. 1]

This consideration leads us to treat of the main objection raised to every descent theory: namely, that never yet has the origin of one species from another been observed, but that, on the contrary, _all species_ -- so far as our experience goes, stretching over thousands of years -- _remain constant_.. [The Theories of Darwin and Their Relation to Philosophy, Religion, and Morality]

He might reply to the dilemma by saying, species do not exist _as species_ in the sense in which they are said to vary (variation applying only to the concrete embodiments of {272} the specific idea), and the evolution of species is demonstrated not by individuals _as individuals_, but as embodiments of different specific ideas.. [On the Genesis of Species]

Action and reaction does not produce the species, nor yet _another species_.. [The Christian Foundation, Or, Scientific and Religious Journal, February, 1880]

The fact is, we do not know of the origin of any two species of animals that do not cross and whose offspring are not fertile; in other words, we do not know of the origin of _species, _ but only of _varieties_.. [Evolution An Investigation and a Critique]

Just in so far as they have adjusted themselves to live in and overcome the opposition of the body-tissues of a certain species of animals, _just to that degree they have incapacitated themselves to live in the tissues of any other species_.. [Preventable Diseases]

It has now been shown, though most briefly and imperfectly, how the law that "_Every species has come into existence coincident both in time and space with a pre-existing closely allied species_," connects together and renders intelligible a vast number of independent and hitherto unexplained facts.. [Contributions to the Theory of Natural Selection A Series of Essays]

The immutability of species, _as he defined species_, was the logical consequence of this theory, and that, it seems to me, is the substantial difference between him and Darwin.. [The Autobiography of a Journalist, Volume I]

These properties, then, which were connoted by the name, logicians seized upon, and called them the essence of the species; and not stopping there, they affirmed them, in the case of the _infima species_, to be the essence of the individual too; for it was their maxim, that the species contained the. [A System Of Logic, Ratiocinative And Inductive (Vol. 1 of 2)]

The fossil species, although belonging to known and existing _genera_, are essentially different in _species_ from those which now live upon the earth.. [The American Quarterly Review, No. 17, March 1831]

It is contended on the other side that we have no evidence of any limits to variation other than those imposed by physical conditions, such, _e. g._, as those which determine the greatest degree of speed possible to any animal (of a given size) moving over the earth's surface; also it is said that the differences in degree of change shown by different domestic animals depend in great measure upon the abundance or scarcity of individuals subjected to man's selection, together with the varying direction and amount of his attention in different cases; finally, it is said that the changes found in nature are within the limits to which the variation of domestic animals extends, -- it being the case that when changes of a certain amount have occurred to a species under nature, it becomes _another species_, or sometimes _two or more other species_ by divergent variations, each of these species being able again to vary and diverge in any useful direction.. [On the Genesis of Species]

_variety_; and so long as it was believed that species were separate creations, or at all events had an origin quite distinct from that of varieties, this law could have no exceptions, because, if any two species had been found to be fertile when crossed and their hybrid offspring to be also fertile, this fact would have been held to prove them to be not _species_ but _varieties_.. [Darwinism (1889)]

(published by the Linnean Society in 1863), he includes under the single species, Rosa canina -- the common dog-rose -- no less than twenty-eight named _varieties_ distinguished by more or less constant characters and often confined to special localities, and to these are referred about seventy of the _species_ of British and continental botanists.. [Darwinism (1889)]

It might be safe and legitimate enough, when we find a fossil organism imbedded in the earth, to ascribe its production to the ordinary law of generation, even although we had not witnessed the fact of its birth, provided the same species is known to have existed previously; but when we find _new races_ coming into being, for which the ordinary law of derivation cannot account, we are not at liberty to apply the same rule to a case so essentially different, and still less to postulate _a spontaneous generation_, or a _transmutation of species_, for which we have no experience at all.. [Modern Atheism under its forms of Pantheism, Materialism, Secularism, Development, and Natural Laws]

'_nature_,' the fact that the human species is _a species_, -- the fact that the human kind is but a _kind_, neighboured with many others from which it is isolated by its native walls of ignorance, -- neighboured with many others, more or less known, known and unknown, more or less. [The Philosophy of the Plays of Shakspere Unfolded]

"illegitimate"; and he remarks that we have here, within the limits of the same species, a degree of sterility which rarely occurs except between plants or animals not only of different _species_ but of different _genera_.. [Darwinism (1889)]

Species Translates

TurkishSpecies English to Turkish Translate
i., tek. ve çoğ., biyol. tür; türlü, çeşit; Kat. dış görünüm; hayal, şekil, görünüş the species insan.i., tek. ve çoğ., biyol. tür; türlü, çeşit; Kat. dış görünüm; hayal, şekil, görünüş the species insan.

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[Vinesauce] Vinny - Species: Artificial Life, Real Evolution [v0.11.0.10]
[Vinesauce] Vinny - Species: Artificial Life, Real Evolution [v0.11.0.10]
SPECIES: ALRE - A New Evolution Simulator Game
SPECIES: ALRE - A New Evolution Simulator Game

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Species Word Data

  • Pronunciations(spēˈshēz, -sēz)
  • Character7
  • Hyphenation spe cies


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