The word species means

In biology, 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. It is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour, or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined.

The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million.^[1][2][3] However, only about 14% of these had been described by 2011.^[3]

All species (except viruses) 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 the species of the genus Boa, with constrictor being the species’ epithet.

While the definitions given above may seem adequate at first glance, when looked at more closely they represent problematic species concepts. For example, the boundaries between closely related species become unclear with hybridisation, in a species complex of hundreds of similar microspecies, and in a ring species. Also, among organisms that reproduce only asexually, the concept of a reproductive species breaks down, and each clone is potentially a microspecies. Although none of these are entirely satisfactory definitions, and while the concept of species may not be a perfect model of life, it is still an incredibly useful tool to scientists and conservationists for studying life on Earth, regardless of the theoretical difficulties. If species were fixed and clearly distinct from one another, there would be no problem, but evolutionary processes cause species to change. This obliges taxonomists to decide, for example, when enough change has occurred to declare that a lineage should be divided into multiple chronospecies, or when populations have diverged to have enough distinct character states to be described as cladistic species.

Species were seen from the time of Aristotle until the 18th century as fixed categories 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 On 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.

Definition[edit]

Biologists and taxonomists have made many attempts to define species, beginning from morphology and moving towards genetics. Early taxonomists such as Linnaeus had no option but to describe what they saw: this was later formalised as the typological or morphological species concept. Ernst Mayr emphasised reproductive isolation, but this, like other species concepts, is hard or even impossible to test.^[4][5] Later biologists have tried to refine Mayr’s definition with the recognition and cohesion concepts, among others.^[6] Many of the concepts are quite similar or overlap, so they are not easy to count: the biologist R. L. Mayden recorded about 24 concepts,^[7] and the philosopher of science John Wilkins counted 26.^[4] Wilkins further grouped the species concepts into seven basic kinds of concepts: (1) agamospecies for asexual organisms (2) biospecies for reproductively isolated sexual organisms (3) ecospecies based on ecological niches (4) evolutionary species based on lineage (5) genetic species based on gene pool (6) morphospecies based on form or phenotype and (7) taxonomic species, a species as determined by a taxonomist.^[8]

Typological or morphological species[edit]

A typological species is a group of organisms in which individuals conform to certain fixed properties (a type), so that even pre-literate people often recognise the same taxon as do modern taxonomists.^[10][11] The clusters of variations or phenotypes within specimens (such as longer or shorter tails) would differentiate the species. This method was used as a «classical» method of determining species, such as with Linnaeus, early in evolutionary theory. However, different phenotypes are not necessarily different species (e.g. a four-winged Drosophila born to a two-winged mother is not a different species). Species named in this manner are called morphospecies.^[12][13]

In the 1970s, Robert R. Sokal, Theodore J. Crovello and Peter Sneath proposed a variation on the morphological species concept, a phenetic species, defined as a set of organisms with a similar phenotype to each other, but a different phenotype from other sets of organisms.^[14] It differs from the morphological species concept in including a numerical measure of distance or similarity to cluster entities based on multivariate comparisons of a reasonably large number of phenotypic traits.^[15]

Recognition and cohesion species[edit]

A mate-recognition species is a group of sexually reproducing organisms that recognise one another as potential mates.^[16][17] Expanding on this to allow for post-mating isolation, a cohesion species is the most inclusive population of individuals having the potential for phenotypic cohesion through intrinsic cohesion mechanisms; no matter whether populations can hybridise successfully, they are still distinct cohesion species if the amount of hybridisation is insufficient to completely mix their respective gene pools.^[18] A further development of the recognition concept is provided by the biosemiotic concept of species.^[19]

Genetic similarity and barcode species[edit]

In microbiology, genes can move freely even between distantly related bacteria, possibly extending to the whole bacterial domain. As a rule of thumb, microbiologists have assumed that members of Bacteria or Archaea with 16S ribosomal RNA gene sequences more similar than 97% to each other need to be checked by DNA–DNA hybridisation to decide if they belong to the same species.^[20] This concept was narrowed in 2006 to a similarity of 98.7%.^[21]

The average nucleotide identity method quantifies genetic distance between entire genomes, using regions of about 10,000 base pairs. With enough data from genomes of one genus, algorithms can be used to categorize species, as for Pseudomonas avellanae in 2013,^[22] and for all sequenced bacteria and archaea since 2020.^[23]

DNA barcoding has been proposed as a way to distinguish species suitable even for non-specialists to use.^[24] One of the barcodes is a region of mitochondrial DNA within the gene for cytochrome c oxidase. A database, Barcode of Life Data System, contains DNA barcode sequences from over 190,000 species.^[25][26] However, scientists such as Rob DeSalle have expressed concern that classical taxonomy and DNA barcoding, which they consider a misnomer, need to be reconciled, as they delimit species differently.^[27] Genetic introgression mediated by endosymbionts and other vectors can further make barcodes ineffective in the identification of species.^[28]

Phylogenetic or cladistic species[edit]

A phylogenetic or cladistic species is «the smallest aggregation of populations (sexual) or lineages (asexual) diagnosable by a unique combination of character states in comparable individuals (semaphoronts)».^[29] The empirical basis – observed character states – provides the evidence to support hypotheses about evolutionarily divergent lineages that have maintained their hereditary integrity through time and space.^{[30][31][32][33]} Molecular markers may be used to determine diagnostic genetic differences in the nuclear or mitochondrial DNA of various species.^[34][29][35] For example, in a study done on fungi, studying the nucleotide characters using cladistic species produced the most accurate results in recognising the numerous fungi species of all the concepts studied.^[35][36] Versions of the phylogenetic species concept that emphasise monophyly or diagnosability^[37] may lead to splitting of existing species, for example in Bovidae, by recognising old subspecies as species, despite the fact that there are no reproductive barriers, and populations may intergrade morphologically.^[38] Others have called this approach taxonomic inflation, diluting the species concept and making taxonomy unstable.^[39] Yet others defend this approach, considering «taxonomic inflation» pejorative and labelling the opposing view as «taxonomic conservatism»; claiming it is politically expedient to split species and recognise smaller populations at the species level, because this means they can more easily be included as endangered in the IUCN red list and can attract conservation legislation and funding.^[40]

Unlike the biological species concept, a cladistic species does not rely on reproductive isolation – its criteria are independent of processes that are integral in other concepts.^[29] Therefore, it applies to asexual lineages.^[34][35] However, it does not always provide clear cut and intuitively satisfying boundaries between taxa, and may require multiple sources of evidence, such as more than one polymorphic locus, to give plausible results.^[35]

Evolutionary species[edit]

An evolutionary species, suggested by George Gaylord Simpson in 1951, is «an entity composed of organisms which maintains its identity from other such entities through time and over space, and which has its own independent evolutionary fate and historical tendencies».^[7][41] This differs from the biological species concept in embodying persistence over time. Wiley and Mayden stated that they see the evolutionary species concept as «identical» to Willi Hennig’s species-as-lineages concept, and asserted that the biological species concept, «the several versions» of the phylogenetic species concept, and the idea that species are of the same kind as higher taxa are not suitable for biodiversity studies (with the intention of estimating the number of species accurately). They further suggested that the concept works for both asexual and sexually-reproducing species.^[42] A version of the concept is Kevin de Queiroz’s «General Lineage Concept of Species».^[43]

Ecological species[edit]

An ecological species is a set of organisms adapted to a particular set of resources, called a niche, in the environment. According to this concept, populations form the discrete phenetic clusters that we recognise as species because the ecological and evolutionary processes controlling how resources are divided up tend to produce those clusters.^[44]

Genetic species[edit]

A genetic species as defined by Robert Baker and Robert Bradley is a set of genetically isolated interbreeding populations. This is similar to Mayr’s Biological Species Concept, but stresses genetic rather than reproductive isolation.^[45] In the 21st century, a genetic species can be established by comparing DNA sequences, but other methods were available earlier, such as comparing karyotypes (sets of chromosomes) and allozymes (enzyme variants).^[46]

Evolutionarily significant unit[edit]

An evolutionarily significant unit (ESU) or «wildlife species»^[47] is a population of organisms considered distinct for purposes of conservation.^[48]

Chronospecies[edit]

In palaeontology, with only comparative anatomy (morphology) from fossils as evidence, the concept of a chronospecies can be applied. During anagenesis (evolution, not necessarily involving branching), palaeontologists seek to identify a sequence of species, each one derived from the phyletically extinct one before through continuous, slow and more or less uniform change. In such a time sequence, palaeontologists assess how much change is required for a morphologically distinct form to be considered a different species from its ancestors.^{[49][50][51][52]}

Viral quasispecies[edit]

Viruses have enormous populations, are doubtfully living since they consist of little more than a string of DNA or RNA in a protein coat, and mutate rapidly. All of these factors make conventional species concepts largely inapplicable.^[53] A viral quasispecies is a group of genotypes related by similar mutations, competing within a highly mutagenic environment, and hence governed by a mutation–selection balance. It is predicted that a viral quasispecies at a low but evolutionarily neutral and highly connected (that is, flat) region in the fitness landscape will outcompete a quasispecies located at a higher but narrower fitness peak in which the surrounding mutants are unfit, «the quasispecies effect» or the «survival of the flattest». There is no suggestion that a viral quasispecies resembles a traditional biological species.^[54][55][56] The International Committee on Taxonomy of Viruses has since 1962 developed a universal taxonomic scheme for viruses; this has stabilised viral taxonomy.^[57][58][59]

Mayr’s biological species concept[edit]

Most modern textbooks make use of Ernst Mayr’s 1942 definition,^[60][61] known as the Biological Species Concept as a basis for further discussion on the definition of species. It is also called a reproductive or isolation concept. This defines a species as^[62]

groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups.^[62]

It has been argued that this definition is a natural consequence of the effect of sexual reproduction on the dynamics of natural selection.^{[63][64][65][66]} Mayr’s use of the adjective «potentially» has been a point of debate; some interpretations exclude unusual or artificial matings that occur only in captivity, or that involve animals capable of mating but that do not normally do so in the wild.^[62]

The species problem[edit]

It is difficult to define a species in a way that applies to all organisms.^[67] The debate about species concepts is called the species problem.^{[62][68][69][70]} The problem was recognised even in 1859, when Darwin wrote in On the Origin of Species:

No one definition has satisfied all naturalists; yet every naturalist knows vaguely what he means when he speaks of a species. Generally the term includes the unknown element of a distinct act of creation.^[71]

When Mayr’s concept breaks down[edit]

A simple textbook definition, following Mayr’s concept, works well for most multi-celled organisms, but breaks down in several situations:

• When organisms reproduce asexually, as in single-celled organisms such as bacteria and other prokaryotes,^[72] and parthenogenetic or apomictic multi-celled organisms. DNA barcoding and phylogenetics are commonly used in these cases.^[73][74][75] The term quasispecies is sometimes used for rapidly mutating entities like viruses.^[76][77]
• When scientists do not know whether two morphologically similar groups of organisms are capable of interbreeding; this is the case with all extinct life-forms in palaeontology, as breeding experiments are not possible.^[78]
• When hybridisation permits substantial gene flow between species.^[79]
• In ring species, when members of adjacent populations in a widely continuous distribution range interbreed successfully but members of more distant populations do not.^[80]

Species identification is made difficult by discordance between molecular and morphological investigations; these can be categorised as two types: (i) one morphology, multiple lineages (e.g. morphological convergence, cryptic species) and (ii) one lineage, multiple morphologies (e.g. phenotypic plasticity, multiple life-cycle stages).^[81] In addition, horizontal gene transfer (HGT) makes it difficult to define a species.^[82] All species definitions assume that an organism acquires its genes from one or two parents very like the «daughter» organism, but that is not what happens in HGT.^[83] There is strong evidence of HGT between very dissimilar groups of prokaryotes, and at least occasionally between dissimilar groups of eukaryotes,^[82] including some crustaceans and echinoderms.^[84]

The evolutionary biologist James Mallet concludes that

there is no easy way to tell whether related geographic or temporal forms belong to the same or different species. Species gaps can be verified only locally and at a point of time. One is forced to admit that Darwin’s insight is correct: any local reality or integrity of species is greatly reduced over large geographic ranges and time periods.^[18]

Wilkins writes that biologists such as the botanist Brent Mishler^[85] have argued that the species concept is not valid, and that «if we were being true to evolution and the consequent phylogenetic approach to taxa, we should replace it with a ‘smallest clade’ idea» (a phylogenetic species concept).^[86] Wilkins states that he concurs^[87] with this approach, while noting the difficulties it would cause to taxonomy. He cites the ichthyologist Charles Tate Regan’s early 20th century remark that «a species is whatever a suitably qualified biologist chooses to call a species».^[86] Wilkins notes that the philosopher Philip Kitcher called this the «cynical species concept»,^[88] and arguing that far from being cynical, it usefully leads to an empirical taxonomy for any given group, based on taxonomists’ experience.^[86]

Aggregates of microspecies[edit]

The species concept is further weakened by the existence of microspecies, groups of organisms, including many plants, with very little genetic variability, usually forming species aggregates.^[89] For example, the dandelion Taraxacum officinale and the blackberry Rubus fruticosus are aggregates with many microspecies—perhaps 400 in the case of the blackberry and over 200 in the dandelion,^[90] complicated by hybridisation, apomixis and polyploidy, making gene flow between populations difficult to determine, and their taxonomy debatable.^[91][92][93] Species complexes occur in insects such as Heliconius butterflies,^[94] vertebrates such as Hypsiboas treefrogs,^[95] and fungi such as the fly agaric.^[96]

• 

  The butterfly genus Heliconius contains many similar species.

Hybridisation[edit]

Natural hybridisation presents a challenge to the concept of a reproductively isolated species, as fertile hybrids permit gene flow between two populations. For example, the carrion crow Corvus corone and the hooded crow Corvus cornix appear and are classified as separate species, yet they can hybridise where their geographical ranges overlap.^[97]

• Hybridisation of carrion and hooded crows permits gene flow between ‘species’

• 

• 

• 

Ring species[edit]

A ring species is a connected series of neighbouring populations, each of which can sexually interbreed with adjacent related populations, but for which there exist at least two «end» populations in the series, which are too distantly related to interbreed, though there is a potential gene flow between each «linked» population.^[98] Such non-breeding, though genetically connected, «end» populations may co-exist in the same region thus closing the ring. Ring species thus present a difficulty for any species concept that relies on reproductive isolation.^[99] However, ring species are at best rare. Proposed examples include the herring gull–lesser black-backed gull complex around the North pole, the Ensatina eschscholtzii group of 19 populations of salamanders in America,^[100] and the greenish warbler in Asia,^[101] but many so-called ring species have turned out to be the result of misclassification leading to questions on whether there really are any ring species.^{[102][103][104][105]}

• 

  Seven «species» of Larus gulls interbreed in a ring around the Arctic.

Taxonomy and naming[edit]

Common and scientific names[edit]

The commonly used names for kinds of organisms are often ambiguous: «cat» could mean the domestic cat, Felis catus, or the cat family, Felidae. Another problem with common names is that they often vary from place to place, so that puma, cougar, catamount, panther, painter and mountain lion all mean Puma concolor in various parts of America, while «panther» may also mean the jaguar (Panthera onca) of Latin America or the leopard (Panthera pardus) of Africa and Asia. In contrast, the scientific names of species are chosen to be unique and universal; they are in two parts used together: the genus as in Puma, and the specific epithet as in concolor.^[106][107]

Species description[edit]

A species is given a taxonomic name when a type specimen is described formally, in a publication that assigns it a unique scientific name. The description typically provides means for identifying the new species, which may not be based solely on morphology^[108] (see cryptic species), differentiating it from other previously described and related or confusable species and provides a validly published name (in botany) or an available name (in zoology) when the paper is accepted for publication. The type material is usually held in a permanent repository, often the research collection of a major museum or university, that allows independent verification and the means to compare specimens.^{[109][110][111]} Describers of new species are asked to choose names that, in the words of the International Code of Zoological Nomenclature, are «appropriate, compact, euphonious, memorable, and do not cause offence».^[112]

Abbreviations[edit]

Books and articles sometimes intentionally do not identify species fully, using the abbreviation «sp.» in the singular or «spp.» (standing for species pluralis, Latin for «multiple species») in the plural in place of the specific name or epithet (e.g. Canis sp.). This commonly occurs when authors are confident that some individuals belong to a particular genus but are not sure to which exact species they belong, as is common in paleontology.^[113]

Authors may also use «spp.» as a short way of saying that something applies to many species within a genus, but not to all. If scientists mean that something applies to all species within a genus, they use the genus name without the specific name or epithet. The names of genera and species are usually printed in italics. However, abbreviations such as «sp.» should not be italicised.^[113]

When a species’s identity is not clear, a specialist may use «cf.» before the epithet to indicate that confirmation is required. The abbreviations «nr.» (near) or «aff.» (affine) may be used when the identity is unclear but when the species appears to be similar to the species mentioned after.^[113]

Identification codes[edit]

With the rise of online databases, codes have been devised to provide identifiers for species that are already defined, including:

• National Center for Biotechnology Information (NCBI) employs a numeric ‘taxid’ or Taxonomy identifier, a «stable unique identifier», e.g., the taxid of Homo sapiens is 9606.^[114]
• Kyoto Encyclopedia of Genes and Genomes (KEGG) employs a three- or four-letter code for a limited number of organisms; in this code, for example, H. sapiens is simply hsa.^[115]
• UniProt employs an «organism mnemonic» of not more than five alphanumeric characters, e.g., HUMAN for H. sapiens.^[116]
• Integrated Taxonomic Information System (ITIS) provides a unique number for each species. The LSID for Homo sapiens is urn:lsid:catalogueoflife.org:taxon:4da6736d-d35f-11e6-9d3f-bc764e092680:col20170225.^[117]

Lumping and splitting[edit]

The naming of a particular species, including which genus (and higher taxa) it is placed in, is a hypothesis about the evolutionary relationships and distinguishability of that group of organisms. As further information comes to hand, the hypothesis may be corroborated or refuted. Sometimes, especially in the past when communication was more difficult, taxonomists working in isolation have given two distinct names to individual organisms later identified as the same species. When two species names are discovered to apply to the same species, the older species name is given priority and usually retained, and the newer name considered as a junior synonym, a process called synonymy. Dividing a taxon into multiple, often new, taxa is called splitting. Taxonomists are often referred to as «lumpers» or «splitters» by their colleagues, depending on their personal approach to recognising differences or commonalities between organisms.^{[118][119][113]} The circumscription of taxa, considered a taxonomic decision at the discretion of cognizant specialists, is not governed by the Codes of Zoological or Botanical Nomenclature.

Broad and narrow senses[edit]

The nomenclatural codes that guide the naming of species, including the ICZN for animals and the ICN for plants, do not make rules for defining the boundaries of the species. Research can change the boundaries, also known as circumscription, based on new evidence. Species may then need to be distinguished by the boundary definitions used, and in such cases the names may be qualified with sensu stricto («in the narrow sense») to denote usage in the exact meaning given by an author such as the person who named the species, while the antonym sensu lato («in the broad sense») denotes a wider usage, for instance including other subspecies. Other abbreviations such as «auct.» («author»), and qualifiers such as «non» («not») may be used to further clarify the sense in which the specified authors delineated or described the species.^{[113][120][121]}

Change[edit]

Species are subject to change, whether by evolving into new species,^[122] exchanging genes with other species,^[123] merging with other species or by becoming extinct.^[124]

Speciation[edit]

The evolutionary process by which biological populations evolve to become distinct or reproductively isolated as species is called speciation.^[125][126] Charles Darwin was the first to describe the role of natural selection in speciation in his 1859 book The Origin of Species.^[127] Speciation depends on a measure of reproductive isolation, a reduced gene flow. This occurs most easily in allopatric speciation, where populations are separated geographically and can diverge gradually as mutations accumulate. Reproductive isolation is threatened by hybridisation, but this can be selected against once a pair of populations have incompatible alleles of the same gene, as described in the Bateson–Dobzhansky–Muller model.^[122] A different mechanism, phyletic speciation, involves one lineage gradually changing over time into a new and distinct form, without increasing the number of resultant species.^[128]

Exchange of genes between species[edit]

Horizontal gene transfer between organisms of different species, either through hybridisation, antigenic shift, or reassortment, is sometimes an important source of genetic variation. Viruses can transfer genes between species. Bacteria can exchange plasmids with bacteria of other species, including some apparently distantly related ones in different phylogenetic domains, making analysis of their relationships difficult, and weakening the concept of a bacterial species.^{[129][82][130][123]}

Louis-Marie Bobay and Howard Ochman suggest, based on analysis of the genomes of many types of bacteria, that they can often be grouped «into communities that regularly swap genes», in much the same way that plants and animals can be grouped into reproductively isolated breeding populations. Bacteria may thus form species, analogous to Mayr’s biological species concept, consisting of asexually reproducing populations that exchange genes by homologous recombination.^[131][132]

Extinction[edit]

A species is extinct when the last individual of that species dies, but it may be functionally extinct well before that moment. It is estimated that over 99 percent of all species that ever lived on Earth, some five billion species, are now extinct. Some of these were in mass extinctions such as those at the ends of the Ordovician, Devonian, Permian, Triassic and Cretaceous periods. Mass extinctions had a variety of causes including volcanic activity, climate change, and changes in oceanic and atmospheric chemistry, and they in turn had major effects on Earth’s ecology, atmosphere, land surface and waters.^[133][134] Another form of extinction is through the assimilation of one species by another through hybridization. The resulting single species has been termed as a «compilospecies».^[135]

Practical implications[edit]

Biologists and conservationists need to categorise and identify organisms in the course of their work. Difficulty assigning organisms reliably to a species constitutes a threat to the validity of research results, for example making measurements of how abundant a species is in an ecosystem moot. Surveys using a phylogenetic species concept reported 48% more species and accordingly smaller populations and ranges than those using nonphylogenetic concepts; this was termed «taxonomic inflation»,^[136] which could cause a false appearance of change to the number of endangered species and consequent political and practical difficulties.^[137][138] Some observers claim that there is an inherent conflict between the desire to understand the processes of speciation and the need to identify and to categorise.^[138]

Conservation laws in many countries make special provisions to prevent species from going extinct. Hybridization zones between two species, one that is protected and one that is not, have sometimes led to conflicts between lawmakers, land owners and conservationists. One of the classic cases in North America is that of the protected northern spotted owl which hybridises with the unprotected California spotted owl and the barred owl; this has led to legal debates.^[139] It has been argued that the species problem is created by the varied uses of the concept of species, and that the solution is to abandon it and all other taxonomic ranks, and use unranked monophyletic groups instead. It has been argued, too, that since species are not comparable, counting them is not a valid measure of biodiversity; alternative measures of phylogenetic biodiversity have been proposed.^[140][141]

History[edit]

Classical forms[edit]

In his biology, Aristotle used the term γένος (génos) to mean a kind, such as a bird or fish, and εἶδος (eidos) to mean a specific form within a kind, such as (within the birds) the crane, eagle, crow, or sparrow. These terms were translated into Latin as «genus» and «species», though they do not correspond to the Linnean terms thus named; today the birds are a class, the cranes are a family, and the crows a genus. A kind was distinguished by its attributes; for instance, a bird has feathers, a beak, wings, a hard-shelled egg, and warm blood. A form was distinguished by being shared by all its members, the young inheriting any variations they might have from their parents. Aristotle believed all kinds and forms to be distinct and unchanging. His approach remained influential until the Renaissance.^[142]

Fixed species[edit]

When observers in the Early Modern period began to develop systems of organization for living things, they placed each kind of animal or plant into a context. Many of these early delineation schemes would now be considered whimsical: schemes included consanguinity based on colour (all plants with yellow flowers) or behaviour (snakes, scorpions and certain biting ants). John Ray, an English naturalist, was the first to attempt a biological definition of species in 1686, as follows:

No surer criterion for determining species has occurred to me than the distinguishing features that perpetuate themselves in propagation from seed. Thus, no matter what variations occur in the individuals or the species, if they spring from the seed of one and the same plant, they are accidental variations and not such as to distinguish a species … Animals likewise that differ specifically preserve their distinct species permanently; one species never springs from the seed of another nor vice versa.^[143]

In the 18th century, the Swedish scientist Carl Linnaeus classified organisms according to shared physical characteristics, and not simply based upon differences.^[144] He established the idea of a taxonomic hierarchy of classification based upon observable characteristics and intended to reflect natural relationships.^[145][146] At the time, however, it was still widely believed that there was no organic connection between species, no matter how similar they appeared. This view was influenced by European scholarly and religious education, which held that the categories of life are dictated by God, forming an Aristotelian hierarchy, the scala naturae or great chain of being. However, whether or not it was supposed to be fixed, the scala (a ladder) inherently implied the possibility of climbing.^[147]

Mutability[edit]

In viewing evidence of hybridisation, Linnaeus recognised that species were not fixed and could change; he did not consider that new species could emerge and maintained a view of divinely fixed species that may alter through processes of hybridisation or acclimatisation.^[148] By the 19th century, naturalists understood that species could change form over time, and that the history of the planet provided enough time for major changes. Jean-Baptiste Lamarck, in his 1809 Zoological Philosophy, described the transmutation of species, proposing that a species could change over time, in a radical departure from Aristotelian thinking.^[149]

In 1859, Charles Darwin and Alfred Russel Wallace provided a compelling account of evolution and the formation of new species. Darwin argued that it was populations that evolved, not individuals, by natural selection from naturally occurring variation among individuals.^[150] This required a new definition of species. Darwin concluded that species are what they appear to be: ideas, provisionally useful for naming groups of interacting individuals, writing:

I look at the term species as one arbitrarily given for the sake of convenience to a set of individuals closely resembling each other … It does not essentially differ from the word variety, which is given to less distinct and more fluctuating forms. The term variety, again, in comparison with mere individual differences, is also applied arbitrarily, and for convenience sake.^[151]

See also[edit]

References[edit]

Sources[edit]

External links[edit]

• Wikispecies – The free species directory that anyone can edit from the Wikimedia Foundation
• Barcoding of species
• Catalogue of Life
• European Species Names in Linnaean, Czech, English, German and French
• «Species» entry at the Stanford Encyclopedia of Philosophy
• VisualTaxa

вид, разновидность, порода, род, класс

существительное ↓

Словосочетания

several different plant and animal species — несколько различных видов животных и растений  
the bipolar distribution of certain species — биполярное распределение некоторых видов  
to lump species — классифицировать виды без учёта мелких различий  
montane species — горный вид  
predatory species of mammals — хищные виды млекопитающих  
rare species — редкие виды  
species becomes extinct / dies out — вид вымирает  
species survives — вид выживает  
trapped species — стабилизированная частица  
species endemic to Zanzibar — эндемичные для Занзибара виды  
adaptable species — адаптирующийся вид  
species-specific antigen — видоспецифический антиген  

Примеры с переводом

Примеры, ожидающие перевода

Возможные однокоренные слова

specie  — металлические деньги, звонкая монета
speciesism  — жестокость по отношению к животным, безразличие к страданиям животных

Формы слова

noun
ед. ч.(singular): species
мн. ч.(plural): species

English[edit]

Etymology[edit]

From Latin speciēs (“appearance; quality”), from speciō (“see”) + -iēs suffix signifying abstract noun. Doublet of spice.

Pronunciation[edit]

• IPA^(key): /ˈspiːʃiːz/, /ˈspiːsiːz/. Some speakers pronounce the singular with -ɪz, the plural with -iːz.
• Rhymes: -iːʃiːz, -iːsiːz

Noun[edit]

species (plural species or (rare, nonstandard) specieses)

1. Type or kind. (Compare race.)

   the male species

   a new species of war

   • 1871, Richard Holt Hutton, Essays, Theological and Literary

     What is called spiritualism should, I think, be called a mental species of materialism.

   • 1930, Norman Lindsay, Redheap, Sydney, N.S.W.: Ure Smith, published 1965, →OCLC, page 122:

     He went on kissing her with unflagging industry, while she remained limply in his arms, in a species of satisfied trance.

   1. A group of plants or animals having similar appearance.

      This species of animal is unique to the area.

      • 1834, L[etitia] E[lizabeth] L[andon], Francesca Carrara. […], volume II, London: Richard Bentley, […], (successor to Henry Colburn), →OCLC, page 103:

        Louise felt raised above her species; a voice had spoken within her inmost soul, whose revealings were vouchsafed but to the chosen few; and what had been indifference, was now disdain.

      • 2012 January 1, Donald Worster, “A Drier and Hotter Future”, in American Scientist, volume 100, number 1, page 70:

        We may see many such [dust] storms in the decades ahead, along with species extinctions, radical disturbance of ecosystems, and intensified social conflict over land and water.

      • 2012, BioWare, Mass Effect 3 (Science Fiction), Redwood City: Electronic Arts, →OCLC, PC, scene: War Assets: Khalisah Bint Sinan al-Jilani:

        Westerlund News Reporter Khalisah Bint Sinan al-Jilani reached out recently to her viewers with a wartime plea for unity and cooperation among all galactic species.
        UPDATED
        Her sincerity touched extranet viewers and donations for war relief efforts are pouring in, both to the Alliance and its alien allies.

   2. (biology, taxonomy) A category in the classification of organisms, ranking below genus; a taxon at that rank.
      • 1992, Rudolf M[athias] Schuster, The Hepaticae and Anthocerotae of North America: East of the Hundredth Meridian, volume V, New York, N.Y.: Columbia University Press, →ISBN, page vii:

        Firstly, I continue to base most species treatments on personally collected material, rather than on herbarium plants.

      • 2013 May-June, David Van Tassel, Lee DeHaan, “Wild Plants to the Rescue”, in American Scientist, volume 101, number 3:

        Plant breeding is always a numbers game. […] The wild species we use are rich in genetic variation, and individual plants are highly heterozygous and do not breed true. In addition, we are looking for rare alleles, so the more plants we try, the better.

   3. (chemistry, physics) A particular type of atom, molecule, ion or other particle.
   4. (mineralogy) A mineral with a unique chemical formula whose crystals belong to a unique crystallographic system.
2. An image, an appearance, a spectacle.
   1. (obsolete) The image of something cast on a surface, or reflected from a surface, or refracted through a lens or telescope; a reflection.

      I cast the species of the Sun onto a sheet of paper through a telescope.

   2. Visible or perceptible presentation; appearance; something perceived.
      • 1704, I[saac] N[ewton], “(please specify |book=1 to 3)”, in Opticks: Or, A Treatise of the Reflexions, Refractions, Inflexions and Colours of Light. […], London: […] Sam[uel] Smith, and Benj[amin] Walford, printers to the Royal Society, […], →OCLC:

        the species of the letters illuminated with indigo and violet

3. (Christianity) Either of the two elements of the Eucharist after they have been consecrated.
4. Coin, or coined silver, gold, or other metal, used as a circulating medium; specie.
   • 1727, John Arbuthnot, Tables of Ancient Coins, Weights and Measures

     There was, in the splendour of the Roman empire, a less quantity of current species in Europe than there is now.

5. A component part of compound medicine; a simple.

Usage notes[edit]

• Species is singular and plural (like sheep, for example). Specie is a separate word that means coin money.
• When species cooccurs with the possessive morpheme -‘, it is generally still pronounced /ˈspiːʃiːz/ ~ /ˈspiːsiːz/, not */ˈspiːʃiːzɪz/ ~ /ˈspiːsiːzɪz/.
• (biology, taxonomy): See species name, binomial nomenclature.

Derived terms[edit]

[edit]

Translations[edit]

See also[edit]

• race
• (taxonomy, rank):
  • domain
  • kingdom
  • phylum/division
  • class
  • order
  • family
  • genus
  • superspecies
  • species
    • subspecies, form
    • (botany, horticulture): variety, cultivar

References[edit]

• John A. Simpson and Edmund S. C. Weiner, editors (1989), “species”, in The Oxford English Dictionary, 2nd edition, Oxford: Clarendon Press, →ISBN.

Noun[edit]

species

1. plural of specie

Dutch[edit]

Pronunciation[edit]

Noun[edit]

species

1. Plural form of specie

Synonyms[edit]

• speciën

Latin[edit]

Etymology[edit]

From speciō (“to see”) +‎ -iēs.

Pronunciation[edit]

• (Classical) IPA^(key): /ˈspe.ki.eːs/, [ˈs̠pɛkieːs̠]
• (Ecclesiastical) IPA^(key): /ˈspe.t͡ʃi.es/, [ˈspɛːt͡ʃies]

Noun[edit]

speciēs f (genitive speciēī); fifth declension

1. a seeing, view, look
2. a spectacle, sight

   Synonym: faciēs

3. external appearance, looks; general outline or shape

   Synonyms: habitus, fōrma, frōns, faciēs

4. semblance, pretence, pretext, outward show (per + genitive)

   Synonym: obtentus
5. show, display
6. point of view, perspective

   • 2021 August, Ross Douthat, “Catholic Ideas and Catholic Realities”, in First Things:

     Sub specie aeternitatis no political system is perfect, and no political system final.

     From the perspective of eternity, ….

7. (figuratively) vision, dream, apparition
8. (figuratively) honor, reputation
9. (figuratively) a kind, quality, type
10. (law, later) a special case

Declension[edit]

Fifth-declension noun.

Case	Singular	Plural
Nominative	speciēs	speciēs
Genitive	speciēī	speciērum
Dative	speciēī	speciēbus
Accusative	speciem	speciēs
Ablative	speciē	speciēbus
Vocative	speciēs	speciēs

Derived terms[edit]

• speciātim
• speciōsus

Descendants[edit]

References[edit]

• “species”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• “species”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
• species in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
• Carl Meißner; Henry William Auden (1894) Latin Phrase-Book‎^[1], London: Macmillan and Co.
  • to see something in a dream: in somnis videre aliquid or speciem
  • I saw a vision in my dreams: species mihi dormienti oblata est
  • an ideal: species optima or eximia, specimen, also simply species, forma
  • to have formed an ideal notion of a thing: comprehensam quandam animo speciem (alicuius rei) habere
  • to pass as a man of great learning: magnam doctrinae speciem prae se ferre
  • to analyse a general division into its specific parts: genus universum in species certas partiri et dividere (Or. 33. 117)
  • to have the appearance of something: speciem alicuius rei habere
  • to give the impression of…; have the outward aspect of..: speciem alicuius rei praebere
  • to give the impression of…; have the outward aspect of..: speciem prae se ferre
  • apparently; to look at: in speciem
  • apparently; to look at: per speciem (alicuius rei)
  • (ambiguous) in truth; really: re (vera), reapse (opp. specie)
  • (ambiguous) apparently; to look at: specie (De Amic. 13. 47)
• Dizionario Latino, Olivetti

Species Definition

A species is a group of organisms that share a genetic heritage, are able to interbreed, and to create offspring that are also fertile. Different species are separated from each other by reproductive barriers. These barriers can be geographical, such as a mountain range separating two populations, or genetic barriers that do not allow for reproduction between the two populations. Scientists have changed their definition of a species several times throughout history.

Species is one of the most specific classification that scientists use to describe animals. Scientists use a system of binomial nomenclature to describe animals without the confusion of common names. This system uses the genus as the first name, which is always capitalized, and the species name is the second name, always lower case. Thus, some animals like the Red fox, Vulpes vulpes, are both in the genus Vulpes and their species name is vulpes. Note the capitalization difference to distinguish between genus and species. Other foxes such as the swift fox, Vulpes velox, are also part of the Vulpes genus, but barriers exist that keep them from interbreeding with the Red foxes. In this way, they remain distinct species.

Since the days of Carl Linnaeus, the creator of binomial nomenclature, animals have been constantly classified and reclassified into different groups, genre, species and subspecies. Linnaeus, classifying organisms in the 1700s, restricted his classifications to the physical attributes of various organisms. Most organism, surprisingly, he correctly identified as being related. Others, however, he couldn’t have been more wrong about. Modern day genetic techniques have given us a much better window into the historical relationships between animals.

For instance, when Linnaeus first classified the elephant in the early 1700s, he only ever saw one specimen. The specimen was a fetal Asian elephant, the smallest of the known elephants today. Not knowing better, Linnaeus named the species Elephas maximus. Modern day scientists have been forced to reclassify the elephant several times. The first distinction is between the Asian and African elephants, which are much different in size. Scientists then further had to distinguish between elephants that inhabited grasslands and those that lived in forests in Africa. Genetics show the populations do not interbreed and are separated by a reproductive barrier.

In the next century, Charles Darwin and Alfred Wallace separately conceived of the mechanism that creates multiple species from a single species. This process of natural selection applies adversity of different forms that organisms must overcome to reproduce. Organisms that are better adapted to the environment are able to reproduce more, and their offspring can also increase in number. In this way, different lines of the same species can do better or worse, depending on their genetics. Eventually, two successful lines may diverge, creating a reproductive barrier between the two populations. These populations, according to Darwin and Wallace, are now considered separate species.

Since the beginning of time, this process has been occurring and dividing organisms along different successful lineages. This theory has been confirmed by a large body of evidence. Fossil evidence provides clues that animals have been constantly changing over time, in response to a variable environment. Where Linnaeus saw animals as static, unchanging entities, it is now widely accepted that species exist on a spectrum, with some being closer related to certain species than others. Because of this, animals can often hybridize, or mate between species.

Examples of Species

Polar bears and Grizzlies

Oftentimes the only barrier to reproduction is geographic, or based on the physical location of the animals. If this changes, the animals can interbreed, and may merge into one species. This is currently being seen in the wild in polar bears and grizzly bears. As the climate changes, polar bears are forced further south, and must start exploiting different food sources. The change in climate also allows grizzly bears to venture further north, encountering polar bears along the way. The previously separated populations now have a chance to breed, and sometimes they are successful. Hybrids have been seen in the wild, but it is not yet known if they hybrids will be successful.

There are many different situations and examples of reproductive barriers, but if the barrier can be removed, it is likely that two related species will be able to interbreed. Non-related species rarely have a possibility of breeding because they have become too different from each other. For instance, a bat and turtle have a completely different genetic makeup. The genes that control growth in the turtle would not function in a bat, and vis-versa. In fact, they don’t even have the same number of chromosomes, which is a requirement for sexually reproducing organisms to be successful.

Dogs and Wolves

Still other animals, like dogs and wolves, are still technically the same species. While they have the same number of chromosomes and could technically breed, the domestic dog has come a long way from its wild counterpart. Dogs have not only evolved to be more cuddly and soft, but are attuned to human social cues. Wolves operate in a much different social structure. As such, the two are very unlikely to breed in the real world. However, because they can create fertile offspring, scientists consider them the same species.

Dogs and wolves are a good example of species radiation, or the incremental changing in a population that is widely distributed. Think of a Chihuahua. If Linnaeus had classified this animal, he certainly would not have put it in the same category as a wolf. However, a Chihuahua can breed with a slightly bigger dog, which can breed with large dog, which could easily breed with a wolf. In this way, a Chihuahua and a wolf have the same genetic basis, expressed in very different ways.

• Hybrid – An organism produced by the crossing of two distinct species.
• Reproductive Barriers – Obstacles that prevent two animals from producing fertile offspring.
• Binomial Nomenclature – The system of naming individual species with two Latin names, the first related to their genus, the second to their species.
• Taxonomical Hierarchy – The system into which all organisms are placed for classification.

Quiz

1. Domestic ferrets and wild black-footed ferrets look almost identical. The black-footed ferret, Mustela nigripes, is native to North America. The domestic ferret, Mustela putorius furo, is native to Europe and only exists in captivity in North America. Could these two populations be one species?
A. No
B. Yes
C. Maybe

2. If scientists tell species apart by how they look, why aren’t males and females that look differently considered different species?
A. They can interbreed
B. Sexual dimorphism is a type of speciation
C. They are considered different species

3. It was recently discovered that what where believed to be two species of trout, one in Russia and one in the US, have almost identical DNA and can reproduce if the eggs and sperm are artificially brought together. The populations are continually separated by saltwater ocean, which they cannot traverse. While some scientists have argued to make them one species, others have argued to keep them separate. What is the argument for keeping them as separate species?
A. They cannot successfully interbreed.
B. They are still separated by a geographical reproductive barrier.
C. There are no good arguments.

Every living organism is unique when you observe its morphological, anatomical, molecular, genetic, biochemical, chemical, physiological characteristics. Based on these different characteristics, scientists have always tried to create groupings that can make their studies simpler and more objective. No matter how long have Homo sapiens existed, they have always been curious about the varied biodiversity around them. The biological nomenclature and classification systems help us in defining biological life with clarity. In the classification systems, a certain hierarchy has been made from higher to the lower level — kingdom, phylum/division, class, order, family, genus, species. The scope of this article is limited to the terminology “species”. So, when asked what is a species? Species is one of the taxonomic ranks that lies at the lowest level of this hierarchical system, generally below the genus rank.

Over time, different scientists have preferred different ways to define this entity called species. Let’s look at them and learn the various different aspects pertaining to species like the concepts of species development, the associated problems with the species concepts, different species, their types, and much more.

Species Definition

In biology, the definition of species goes by this: “Species is the lowest taxonomic rank and the most basic unit or category of biological classification”. One can also define species as an individual belonging to a group of organisms (or the entire group itself) having common characteristics and (usually) are capable of mating with one another to produce fertile offspring.

Some pointers related to species are:

1. Etymology: The word species is itself a late Middle English word derived from a Latin word “specere”, which means “to look”, “kind”, “appearance”, “form” (of something).
2. Composition: Populations of organisms that can interbreed and produce fertile offspring comprise a species. These individual organisms can exchange genes.
3. Position: Species ranks below the taxonomic rank “genus”. A genus encompasses many different species.
4. Denotation: A species is always denoted by a Latin binomial, in which the first one is the name of the genus to which a particular species belongs and the second one is the species name. These are called generic epithet and specific epithet. This binomial nomenclature system was first used by Carl Linnaeus. The generic epithet is always capitalized while the specific epithet isn’t, although both are italicized. For example, human beings belong to the species “Homo sapiens”.
5. Representatives: The representatives of a species are populations, subspecies, cultivars, races, varieties, etc. They aren’t usually considered as separate taxonomic ranks within the classification system but are considered groups that help the biological studies easier. The individuals of a population have some common characteristic features and attributes.
6. Different ways to define species: There are many different ways to define species- morphological, ecological, evolutionary, phylogenetic, biological.

Now that you understand the species meaning, let’s move to the little intricacies and decipher their meaning.

Biology definition:
Species is the lowest taxonomic rank and the most basic unit or category of biological classification consisting of organisms that share common characteristics and generally are capable of reproducing to produce fertile offspring. There are certain groups though that can still be further subdivided into subgroups (i.e. subspecies, such as varieties, formae, etc.). A species is given a two-part name: the generic name and the specific name (or specific epithet). For example, Allium cepa (commonly known as onion). The “Allium” is the generic name whereas the “cepa” is the specific epithet. Etymology: Middle English, logical classification, from Latin speciēs, a seeing, kind, form”.  Abbreviation: sp. See also: genus, taxon

History

The concept of species has a long-standing history. From views cemented on a “fixed nature” of a species to “continuously evolving nature” of species, the Science of Taxonomy, Systematics and Evolutionary Biology has transformed leaps and bounds. Let’s take a quick look at some historical milestones:

1. Aristotle View: Aristotle, the great Greek polymath, was of the view that a species is a fixed “form” in a “kind”. For example: if a kind is “plants”, a form is a subset of it, let’s say “flowering plants”. A kind is different from other kinds because it possesses some typical characteristic features that the other kinds don’t have. Furthermore, a particular form within a kind is even more specific. Also, these kinds and forms are unchanging over time and fixed in their nature.
2. John Ray View: John Ray, the great naturalist of the 1600s, was the first one to attempt to define species in the biological concept. He shed some light on the species concept by explaining that one species of plant perpetuates itself by leaving inoculum for its continuation in a seed. From a seed of a particular plant, only that particular species will live on.
3. Carl Linnaeus View: Carl Linnaeus, the father of modern taxonomy, was the first one who gave a well-defined classification system for biological diversity. His idea of hierarchy in taxonomic classification systems was based on shared physical characters. He didn’t take only the differences into account, but also the shared attributes. But even in Linnaeus’ view, the species didn’t get the reputation of evolution over time; it was being juggled between static and dynamic nature.
   
4. 19th Century Scientists’ View: Species aren’t fixed in nature and can change/evolve over time.
5. Jean-Baptiste Lamarck View: In the 1800s, the widely known scientist for the concept of Lamarckism gave another theory of “transmutation of species”. According to this, one species can alter into another. This was described in his book named Philosophie Zoologique. He believed that new species are formed by spontaneous generation and one species can change within the lifetime of an individual and those changes can be inherited by the progeny. This theory invited a lot of backlashes.
   
6. Charles Darwin and Alfred Wallace View: These 2 scientists and philosophers gave compelling accounts of how species change over time. They insisted that it’s the populations of individuals that change, and not the individuals themselves. This happens by a process called natural selection. They made it clear that species aren’t fixed by nature, but continuously evolving entities and this evolution/change doesn’t happen in one generation but takes many years and generations.

Types of Species

Different species can be defined based on the different concepts. Let’s first look at the different species concepts.

Morphological species concept

It is based solely on the morphology of the species, pertaining only to the physical appearance of the organisms. Pros of this concept for defining and describing a species are that it’s an easy and handy method for species identification. It works equally well for layman and taxonomical experts as the morphological features are easily identifiable by everyone rather than genetic and chemical analytics. It is also called the typological species concept. It was considered by Aristotle, Plato, and Cain in their philosophies.

Phenetic species concept

This is a slight modification of the morphological species concept. It was given by Robert R. Sokal, Theodore J. Crovello, and Peter Sneath. They explained that a phenetic species is one in which all the individuals of a species have a similar phenotype but it is significantly different from the organisms of the other phenetic species. This is different from the morphological species concept as a larger number of phenotypic traits are taken into consideration here. Additionally, there is a numerical figure associated with it to objectively differentiate one species from another.

Phylogenetic species concept

According to this concept, a species is the smallest monophyletic aggregation that has unique, characteristic, distinguishable synapomorphies; meaning shared derived characteristics. These aggregations or groups are comprised of populations (for sexually reproducing organisms) and lineages (for asexually reproducing organisms).

Biological species concept

This concept was given by Ernst Mayr. It is also called the reproductive isolation concept. It is stated that a species is a group of natural populations that interbreed among themselves (actually or potentially) but don’t do the same with other groups as they are “reproductively isolated” from them. This is by far the most widely accepted species concept as of this time.

Evolutionary species concept

This concept defines a species as an independently evolving entity. The reason this concept is widely accepted is that such a species persists through long time periods. This concept works equally well for both sexually and asexually reproducing organisms. Eminent scientists like George Gaylord Simpson and Wiley have postulated this in their theories.

Ecological species concept

Ecological species concepts explain that a species is a group of organisms that thrive and exploit the same niche. In a single range, even if there’s some minimal difference in the specific factors of a niche, the 2 different sets of organisms are called 2 different ecological species.

Now that we have discussed the different species concepts, let’s move forward and learn the different types of species.

1. Endangered species – An endangered species is one that is prone to get extinct in the near future. With the declining numbers of such species, the risks of losing diversity increase. Many national and international ventures aim to protect and restore the natural populations of such endangered species.
   Example: California Condors are critically endangered species.
   
2. Dominant species – Dominant species are those species that form the majority in an ecological community. They usually make up the bulk of the biomass in such a community. Usually, any ecological community is always defined by its dominant species.
   Example: Rhizophoraceae (mangroves) are the dominant species of tidal swamps. In fact, such forests are called mangrove forests. Sundarban Mangrove forests of Bangladesh and India are the largest continuous mangrove forests of the world.
   
3. Pioneer species – Pioneer species are those that colonize barren lands for the first time or steady-state ecosystems after they have been disrupted by some environmental or manmade interventions.
   Example: Lichen species are the most common pioneer species for primary succession as they have the unique ability to colonize even barren rocks. Read our article on Pioneer species for more details.
   
4. Rare species – Rare species are those which are encountered very less or have no extensive records. They are uncommon and this makes them precious in some aspects. This is one of the many statuses given by IUCN like endangered, extinct, rare, etc. They have small population sizes, less genetic variability among individuals, and more vulnerability to get endangered and extinct. The chances of these species to recover after ecological disasters are very bleak.
   Example: Hornbills and Fennec foxes are examples of rare species.
   
5. Exotic species – Species are called exotic when they are encountered outside their native ranges or places where they have not originally evolved. This presence of species outside their native ranges puts the native species at risk and under unwanted pressure- competition for food, resources, etc.
   Example: Rambutan is an exotic fruit in India as its native range is actually Malaysia.
   
6. Early seral species – Early seral species are those species that start growing in natural succession soon after a disturbance (fire or logging).
   Example: Ponderosa pine.
   
7. Type species – Type species are those species that have been used during taxonomic work for naming that particular species.

Species Examples

Examples of some species:

• Flora: Cinnamomum verum (true cinnamon tree), Trichopus zeylanicus, Mangifera indica (mango), Musa acuminata (banana)
• Fauna: Felis catus (cat), Bos tauras (cattle), Canis lupus familiarise (dog), Elephas maximus indicus (Indian elephant)
• Fungi: Aspergillus niger, Penicillium notatum, Agaricus bisporus, Grifola frondosa
• Bacteria: Bacillus cereus, Pseudomonas aeruginosa, Streptococcus mutans, Salmonella choleraesuis

Taxonomy and Naming

Here are some of the basic and important notes about the taxonomy and naming of organisms.

• Vernacular names are often confusing, hence taxonomic names are given to each biological organism.
• While systematically naming biological life, “type specimens” are used.
• Pros of using scientific name: unique, objective to understand, universal
• The plural of species (sp.) is species (spp.).

Mayr’s Biological Species Concept

This concept was given by Ernst Mayr. It is also called the reproductive isolation concept. It is stated that a species is a group of natural populations that interbreed among themselves (actually or potentially) but don’t do the same with other groups as they are “reproductively isolated” from them. It is the most widely accepted species concept.

The species problem

There has been a long withstanding debate on the concept of “species delimitation” and is generally referred to as the “the species problem”.
Reason: It’s very difficult to define the term species for different biological organisms
Problem recognition by: Charles Darwin (in 1859)

Change

The various ways by which species change are:

• Evolution of old species into new species (Speciation)
• Active exchange of genes of one species with another
• One species merged into another
• Extinction of a species

Practical Implications

• If researchers aren’t able to recognize and identify organisms to the correct species, it will create a lot of confusion and pose a threat to the validity of research work.
• Possibility of taxonomic inflation
• The intrinsic conflict between 2 ideologies- one is the desire to identify each organism to species level and the second is to identify and understand the process of speciation.

Try to answer the quiz below to check what you have learned so far about species.

Further Reading

• What is a Genus?
• Scientific name – Definition and Examples
• The Homo Species – Biology Online Tutorial

References

• Crow J. F. (2009). Mayr, mathematics and the study of evolution. Journal of biology, 8(2), 13. https://doi.org/10.1186/jbiol117
• Claridge, M. F.; Dawah, H. A.; Wilson, M. R., eds. (1997). Species: The Units of Biodiversity. Chapman & Hall. ISBN 978-0-412-63120-7.
• Tănase, A. M., Vassu, T., & Stoica, I. (2010). Conceptul de specie bacteriană [The concept of bacterial species]. Bacteriologia, virusologia, parazitologia, epidemiologia (Bucharest, Romania : 1990), 55(1), 5–10.
• Aldhebiani A. Y. (2018). Species concept and speciation. Saudi journal of biological sciences, 25(3), 437–440. https://doi.org/10.1016/j.sjbs.2017.04.013
• BURMA, B. H., & MAYR, E. (1949). The species concept. Evolution; international journal of organic evolution, 3(4), 369–373. https://doi.org/10.1111/j.1558-5646.1949.tb00037.x
• MANSFELD R. (1948). Ueber den Artbegriff in der systematischen Botanik [About the concept of species in systematic botany]. Biologisches Zentralblatt, 67(7-8), 320–331.
• Chen S. X. (1983). Species concept and taxonomic principles. Scientia Sinica. Series B, Chemical, biological, agricultural, medical & earth sciences, 26(10), 1037–1045.
• Wheeler Q. D. (1999). Why the phylogenetic species concept?-Elementary. Journal of nematology, 31(2), 134–141.

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2	1   1 Species late 14c. as a classification in logic, from Latin species «a particular sort, kind, or type» (opposed to genus), originally «a sight, look, view, appearance,» hence also «a s [..]

3	1   1 Species group of similar organisms that can reproduce with each other.

4	1   1 Species Related strains of a plant that occur naturally.

5

1   1 Species A level of hierarchy in plant classification. All plants are classified or identified by placing them in groups or categories to show relationships. All plants can be identified or associated with successive categories that are arranged hierarchically, as follows: Kingdom, Division, Class, Order, Family, Genus, Species. When people discuss plant na [..]

6	1   1 Species Plant groupings that have the same general characteristics

7	1   1 Species (specific name)

8	1   1 Species see binomial nomenclature

9	1   1 Species A plant, or a group of closely related plants, within a genus. Species have distinctive characteristics and always breed true to type from seed.

10	1   1 Species A natural group of plants composed of similar individuals which can produce similar offspring, usually including several minor variations; a unit of botanical classification capable of reproducing itself. Spicate

11	1   1 Species "A group of interbreeding individuals" provides the beginnings of a definition for sexually reproducing organisms. For non-sexually reproducing organisms, such as bacteria and apomic [..]

12	1   1 Species In plant classification, a group of plants with common characteristics that can cross-breed with one another.

13	1   1 Species A group of organisms that is capable of interbreeding to produce fertile offspring. However, this biological test of a species is not always available, so there is also a morphological species concept based on anatomical similarities.

14	1   1 Species Plants within a species have several characteristics in common, but most importantly, can cross with one another, but not normally with members of another species. The classification of species is qui [..]

15	0   0 Species indicates plants that have additional common attributes and similar methods of reproduction.

16

0   0 Species The basic scientific name for plants and animals. A species has two names, the genus, whose first letter is capitalized; and the species name, which describes some physical feature or geographic location or honors some prominent plant scientist. Red Maple has the scientific name Acer rubrum

17	0   0 Species A plant classification under a genus.

18

0   0 Species The basic unit of plant or animal classification. Plants within a individual species have several characteristics in common. Most importantly, they can cross with one another, but normally not with members of other species. Classification of species is quite fluid, with periodic revision by botanists.

19	0   0 Species A kind of plant distinct from other kinds and reproducing its characteristics when self-pollinated. The second, uncapitalized word in the scientific name of a plant.

20	0   0 Species                    A group of plants that share the same characteristics.

21	0   0 Species  A set of individuals that are closely related by descent from a common ancestor and can reproduce with each other but not with members of another species.

22	0   0 Species a group of organisms that can breed with each other.

23	0   0 Species A group of plants resembling each other in all but minor details and which can interbreed easily and successfully.

24	0   0 Species (biology) taxonomic group whose members can interbreed a specific kind of something; "a species of molecule"; "a species of villainy" In biology, a [..]

25	0   0 Species n. A classificatory group of animals or plants subordinate to a genus.

26	0   0 Species Species is one of the seven taxonomic ranks used to classify living organisms. A species is a group of organisms that can breed and produce fertile offspring. Read more on: Species

27	0   0 Species A biological species is a group of organisms that can reproduce with one another in nature and produce fertile offspring

28	0   0 Species a basic unit of biological taxonomy that groups organisms that are able to interbreed and have fertile offspring.

29	0   0 Species species (pop)

30	0   0 Species Every living creature is assigned a species name, grouping it with a class of related organisms that share similar characteristics. Organisms must be able to interbreed and create viable offspring to [..]

31	0   0 Species a taxon comprising individuals, or populations of individuals, that show certain common features and are capable of interbreeding to produce fertile offspring. cf. genus.

32	0   0 Species A sub-division of a genus, abbreviated to sp. in the singular and spp. in the plural. (See also Genus

33	0   0 Species trees with similar characteristics and that are closely related to each other; species is used in both the singular and plural sense (specie is not proper).

34	0   0 Species Most specific level of scientific classification; below Genus

35	0   0 Species (L: specere=to look; species= appearance, kind, beauty) a natural group of organisms, the members of which interbreed to give similar offspring. The smallest unit of classification commonly used. The [..]

36	0   0 Species An important classificatory category, which can be variously defined by the biological species concept

37

0   0 Species A group of organisms (individuals) that can interbreed and reproduce with each other. Used to distinguish sexually reproducing organisms into groups. Individuals from two different species cannot have offspring. They are said to be reproductively isolated. The biologist Ernst Mayr formulated this definition of a species advancing our understanding [..]

38	0   0 Species A group of individuals that can readily interbreed to produce fertile offspring. Individuals of different species produce either no offspring or infertile offspring. See Figure 6.3.

39	0   0 Species A subdivision of the genus, a species is a group of closely related and similar-looking organisms; for example, in the case of Homo sapiens (humans), the second part of the name (sapiens) represents t [..]

40	0   0 Species the fundamental category of taxonomic classification, ranking below a genus or subgenus and consisting of related organisms capable of interbreeding.

41	0   0 Species An important classificatory category, which can be variously defined by the biological species concept, cladistic species concept, ecological species concept, phenetic species concept, and recognition [..]

42	0   0 Species A segment of a population-level lineage that is evolving separately from other such lineage segments as indicated by one or more lines of evidence (e.g., distinguishability, reproductive isolation, mo [..]

43	0   0 Species (French : espèce) Branch of natural sciences that concerns similar individuals that can reproduce within themselves.

44	0   0 Species A group of similar organisms that can breed and produce fertile offspring

45	0   0 Species A group of living organisms that are able to reproduce and create fertile offspring.

46	0   0 Species Organisms whose members are alike and successfully reproduce among themselves.

47

0   0 Species A specific charged particle that was implanted in an ion implantation process. Note that the species is the specific charged particle that was accelerated and injected into the wafer, not necessarily the dopant element that was activated in the silicon. Specifying the species means specifying all of the following information: 1) the chemical elemen [..]

48	0   0 Species

49	0   0 Species  the taxonomic rank after genus that includes closely related organisms that are potentially able to breed with one another. If the genus of a creature is known, but the species isn’t, you will see something to this effect: Steatoda

50

0   0 Species A taxonomic category subordinate to a genus (or subgenus) and superior to a subspecies or variety, composed of individuals possessing common characters distinguishing them from other categories of individuals of the same taxonomic level. In taxonomic nomenclature, species are designated by the genus name followed by a Latin or Latinized adjective o [..]

51	0   0 Species A population of morphologically similar organisms that can reproduce sexually among themselves but cannot produce fertile offspring when mated with other organisms.

52	0   0 Species a basic level of life-form in the Linnaean classification—a group of organisms capable of interbreeding and producing fertile offspring—for example, Agathis australis is the species name for kauri trees

53	0   0 Species   A category of biological classification designating a type of organism or population of animals potentially capable of interbreeding; the two known populations of the single human species are Homo [..]

54	0   0 Species Pursuant to 50 CFR 81.1 [Title 50 — Wildlife and Fisheries, Chapter I — United States Fish and Wildlife Service, Department of The Interior], the term species includes any subspecies of fish or wild [..]

55	0   0 Species (n) (biology) taxonomic group whose members can interbreed(n) a specific kind of something

56	0   0 Species a group of organisms that breed with each other to produce fertile offspring.

57	0   0 Species A taxonomic division that generally refers to a group of animals which are similar in structure and descent and are able to breed among themselves.

58	0   0 Species A population or group of populations that are in reproductive contact but are re-productively isolated from all other populations

59	0   0 Species N F sight| appearance| show; splendor| beauty; kind| type

60	0   0 Species A group of individuals that have many of the same characteristics, and are different from all other animals in some important way. Hamsters and mice are two different species of rodent.

61	0   0 Species Classification category into which similar individuals in the plant or animal kingdom are placed. Related organisms or populations potentially capable of interbreeding.

62	0   0 Species a distinct type of organism

63	0   0 Species  All organisms capable of breeding freely with each other under natural conditionS.

64	0   0 Species A group of plants or animals that inter-breed.

65	0   0 Species A group of individuals that can interbreed and beget fertile offspring.

66	0   0 Species This term refers to all the individual organisms of a natural population which are able to interbreed, generally sharing similar appearance, characteristics and genetics due to having relatively recent common ancestors

67	0   0 Species Each Genus is divided into several species, with this species providing the second taxonomical name for an organism. For example, the species lupus can be found under the Genus Canis. Canis lupus is the taxonomical name for the Grey Wolf

68	0   0 Species A group of organisms formally recognized as distinct from other groups.

69	0   0 Species a particular kind of plant or animal. The red fox is on species; the gray fox is a different species.

70	0   0 Species A reproductively isolated aggregate of interbreeding organisms.

71	0   0 Species 1. A reproductively isolated aggregate of interbreeding organisms having common attributes and usually designated by a common name.2. An organism belonging to belonging to such a category.

72	0   0 Species 1. A reproductively isolated aggregate of interbreeding organisms having common attributes and usually designated by a common name.2. An organism belonging to belonging to such a category.

73	0   0 Species A category of taxonomic classification, ranking below a genus or subgenus and consisting of related organisms capable of interbreeding. Also refers to an organism belonging to such a category.

74	0   0 Species Species is a biological classification for a group of organisms that have the capacity to interbreed and produce fertile offspring.

75	0   0 Species A category of living things that ranks below a genus, is made up of related individuals able to produce fertile offspring and is identified by a two-part scientific name.

76

0   0 Species   Highly controversial term given a variety of definitions by biologists. Currently, the Biological Species Concept (BSC) is widely popular: Groups of actually or potentially interbreeding populations, which are reproductively isolated from other such groups (Mayr 1963) . (W. R. Elsberry talk.origins via W.J. Hudson) See also cladistic species con [..]

77	0   0 Species and monophyletic groups. A species is a lineage. It is a taxon that represents the largest unit of taxic evolution and is associated with an array of processes termed speciation. Members of a monophyl [..]

78	0   0 Species in biology, and science in general, refers to a group of organisms that are similar and capable of exchanging genes, or interbreeding

79	0   0 Species An Animal or Plant species in danger of extinction. Causes can include Human Activity, changing Climate, or change in predator/prey ratios.

80	0   0 Species Non-native organisms brought into a region, habitat, or Ecosystem by Human Activity.

81	0   0 Species Non-native species that threaten Ecosystems, habitats, or other species and are likely to cause economic or environmental harm or harm to Human Health.

82	0   0 Species Nitrogenous products of Nitric Oxide synthases, ranging from Nitric Oxide to Nitrates. These reactive Nitrogen intermediates also include the inorganic Peroxynitrous Acid and the organic S-Nitrosothio [..]

83	0   0 Species An Animal or Plant species likely to become endangered within the foreseeable future.

84	0   0 Species A species is the basic unit in classification and in the study of evolution. In practice a species is recognized and defined by its phenetic appearance. However, the theoretical problem of what actual [..]

85	0   0 Species A single distinct kind of plant or animal having certain distinguishing characteristics; a taxonomic category for a group of related organisms that form the largest unit of population within which eff [..]

86	0   0 Species In living animals a group of populations (Biological species) that can actually or potentially interbreed and have fertile offspring, and are reproductively isolated from other species. Also see Evolu [..]

87	0   0 Species A subdivision of a basic biological group, the genus, containing individuals that resemble one another and that may interbreed.

88

0   0 Species     Difficult to define rigorously in two or three lines. Defined very simply in a phylogenetic context, species are the smallest lineages that are mutually exclusive of other lineages. The internal branches of a phylogeny may be viewed as ancestral species. Note, however, that the unit lineages of a gene phylogeny are not species (see also ter [..]

89	0   0 Species A subgroup of genus and part of the classification system scientists use to identify plants and animals. Although there is some debate among scientists, two species of wolves are recognized in the U.S [..]

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0   0 Species the basic unit of biological classification.  Generally defined as an aggregation of individuals similar in appearance and structure, mating freely and producing young that themselves mate freely and bear fertile offspring.  Abbreviated to sp. for one species and spp. for two or more species.

91	0   0 Species A group of individuals biologically capable of interbreeding and which have a common ancestor.

92	0   0 Species The basic unit of living things, consisting of a group of individuals which all look more or less alike and which can all breed with each other to produce another generation of similar creatures. Sper [..]

93	0   0 Species organisms in the same genus that have similar characteristics.

94	0   0 Species A class of plants or animals having common attributes and designated by a common name. Theoretically, plants or animals of different species cannot interbreed. However, occasionally this does not hold [..]

95	0   0 Species A group of organisms capable of interbreeding freely with each other but not with members of other species.

96	0   0 Species The seventh and smallest group that scientists classify living things into. Actually, only one organism is in this group. Each genus is split into species. Also, a particular species of organism must [..]

97	0   0 Species

98	0   0 Species   The basic unit of living things, consisting of a group of individuals which all look more or less alike and which can all breed with each other to produce another generation of similar creatures. M [..]

99	0   0 Species a category of living things that can produce fertile offspring

100	0   0 Species A group of individuals that interbreed, producing and maintaining genetically identical fertile healthy offspring over a period of millions of generations. By definition a species cannot interbreed wi [..]

101	0   0 Species a group of individuals similar in morphology, capable of interbreeding and producing fertile offspring. They are morphologically different from other groups and usually do not interbreed with them.

102	0   0 Species ("spee-sees"): a group of like organisms that look and act very much alike, having very similar genes. They are most often defined by their ability to breed together. There are excep [..]

103

0   0 Species ‘Species’ refers to a type of microorganism existing within a genus or family. For example, acidophilus is the name of a species within the Lactobacillus genus. Different species within the same genus (eg. acidophilus and rhamnosus) are generally considered to be more closely related to each other than species from other genera (for examp [..]

104	0   0 Species a single kind of organism; white-tail and mule are different species of deer

105	0   0 Species A single, distinct class of living creature with features that distinguish it from others.

106	0   0 Species A group of living organisms that can interbreed to produce viable offspring.

107	0   0 Species Basic category of biological classification, characterized by individuals which can breed together and produce offspring which can also produce young.

108	0   0 Species That’s actually a deep subject,

109	0   0 Species is a set of creatures which, in their natural setting, breed among themselves.

110	0   0 Species ‘Species’ refers to a type of microorganism existing within a genus or family. For example, acidophilus is the name of a species within the Lactobacillus genus. Different species within the [..]

111	0   0 Species A group of organisms made up of similar individuals that are capable of breeding with one another.

112

0   0 Species A taxonomic category subordinate to a genus (or subgenus) and superior to a subspecies or variety, composed of individuals possessing common characters distinguishing them from other categories of individuals of the same taxonomic level. In taxonomic nomenclature, species are designated by the genus name followed by a Latin or Latinized adjective o [..]

113	0   0 Species In mineralogy, a mineral with unique chemical and/or physical properties that differentiate it from all other minerals.

114	0   0 Species «Species» means any species or subspecies of wildlife.

115	0   0 Species The basic unit of plant or animal classification. Plants within a individual species have several characteristics in common. Most importantly, they can cross with one another, but normally not with me [..]

116	0   0 Species  Depending on how they were listed under the ESA, species is defined as species, subspecies, distinct population segment (DPS), or Evolutionarily Significant Unit (ESU).

117	0   0 Species A group of similar organisms capable of interbreeding and producing fertile offspring.

118

0   0 Species In the sense of biological species, the members of a group of populations that interbreed or potentially interbreed with one another under natural conditions; a complex concept (see Chapter 17). Also, a fundamental taxonomic category to which individual specimens are assigned, which often but not always corresponds to the biological species. See al [..]

119	0   0 Species A group of related organisms that are capable of breeding with each other to produce fertile offspring but are not capable of breeding with members of other species.

120	0   0 Species The species designations of animals under study.

121	0   0 Species For purposes of the Endangered Species Act, this term includes any species or subspecies of fish or wildlife or plants, and any distinct population segment of any species of vertebrate fish or wildlife which interbreeds when mature.

122	0   0 Species a group of individual whose members can breed and create viable offspring

123	0   0 Species A group of individuals that have their major characteristics in common and (usually) can only breed with each other.

124	0   0 Species The species, an adjective, often refers to a place, the plant’s characteristics/appearance, or the name of the person credited with discovering it. Species is abbreviated sp. or spp.

125	0   0 Species 1. A reproductively isolated aggregate of interbreeding organisms having common attributes and usually designated by a common name.2. An organism belonging to belonging to such a category.

126	0   0 Species Any subspecies of fish or wildlife or plants, and any distinct population segment of any species of vertebrate fish or wildlife that interbreeds when mature.

127	0   0 Species a group of plants or animals that share certain characteristics and are able to breed and reproduce their own kind. stalk:

128	0   0 Species A group of similar individuals having a common origin and continuous reeding system.

129	0   0 Species   individuals of the same type which are able to interbreed to produce fertile offspring under natural conditions contributing to a common gene pool.

130	0   0 Species A group of similar living animals that reproduce to produce fertile young.

131	0   0 Species A group of organisms whose members can reproduce only with one another.

132	0   0 Species The term species is usually defined as a group of organisms, within which individuals are capable of interbreeding and producing fertile offspring. Usually, individuals within a species look and behav [..]

133	0   0 Species A type or kind of thing. *(1826-1897) *: What is called spiritualism should, I think, be called a mental species of materialism. # A group of plants or animals having similar appearance. #: (Thi [..]

134	0   0 Species A group of related organisms having common characteristics and capable of interbreeding. Loblolly and Virginia pine are common tree species that can interbreed.

135	0   0 Species  A classification of living organisms which are capable of interbreeding and producing fertile offspring.

136	0   0 Species An aggregation of individuals and populations that can potentially interbreed and produce fertile offspring, and is reproductively isolated from other such groups.

137	0   0 Species Species is a 1995 American science fiction horror film directed by Roger Donaldson and written by Dennis Feldman. It stars Natasha Henstridge (in her debut film role), Ben Kingsley, Michael Madsen, Al [..]

138	0   0 Species Species is one of the basic units of biological classification. Species may also refer to:

139	0   0 Species Species, in metaphysics, is a specific genus-differentia defined item that is described first by its genus (genos) and then its differentia (diaphora). Put differently, it is an item, not necessarily [..]

140	0   0 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 conserv [..]

141	0   0 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 conserv [..]

142	0   0 Species An accident, in philosophy, is an attribute that may or may not belong to a subject, without affecting its essence. Aristotle made a distinction between the essential and accidental properties of a th [..]

143	0   1 Species individual plants bearing certain characters in common. Spike

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What does the word species mean?

species. [ spē′shēz, spē′sēz ] A group of organisms having many characteristics in common and ranking below a genus. Organisms that reproduce sexually and belong to the same species interbreed and produce fertile offspring.

What does species literally mean?

(Entry 1 of 2) 1a : kind, sort. b : a class of individuals having common attributes and designated by a common name specifically : a logical division of a genus or more comprehensive class confessing sins in species and in number.

What does species mean in your own words?

The definition of a species is a group of animals, plants or other living things that all share common characteristics and that are all classified as alike in some manner. An example of a species is all human beings.

What 3 things define a species?

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. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche.

What makes a species unique?

Most evolutionary biologists distinguish one species from another based on reproductivity: members of different species either won’t or can’t mate with one another, or, if they do, the resulting offspring are often sterile, unviable, or suffer some other sort of reduced fitness.

How do you explain a species to a child?

A species is the most detailed form of classification of living things. For example, you might group all my blue jeans together in my closet. In living things, a species is a group of similar individuals that are able to reproduce. There are estimated to be about nine million species on Earth!

What is species in simple words?

Species, in biology, classification comprising related organisms that share common characteristics and are capable of interbreeding. This biological species concept is widely used in biology and related fields of study.

Which is the best definition of species?

A species is often defined as a group of organisms that can reproduce naturally with one another and create fertile offspring.

What are species Class 6?

Species is defined as a group of organisms that consist of similar individuals capable of interbreeding or exchanging genes among themselves.

What are species for Class 8?

Species: A group of population or populations whose members have common characteristics and are capable of interbreeding among themselves to produce fertile off-springs.

What is the systematic position of man?

Human taxonomy is the classification of the human species (systematic name Homo sapiens, Latin: “wise man”) within zoological taxonomy….Human taxonomy.

Homo (“humans”) Temporal range: Piacenzian-Present, 2.865–0 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Scientific classification
Subfamily:	Homininae
Tribe:	Hominini
Genus:	Homo Linnaeus, 1758

What is typological species concept?

Typological Species Concept: a group of organisms conforming to a common morphological plan, emphasizing the species as an essentially static, non-variable assemblage. Geneological Species Concept: an exclusive group of organisms whose members more closely resemble one another than members of any outside group.

What are the 4 species concepts?

Typological or Essentialist Species Concept 2. Nominalistic Species Concept 3. Biological Species Concept 4. Evolutionary Species Concept.

What is Hennigian species concept?

The Hennigian species concept incorporated the interbreeding model of a biological species concept, but with a historical component. This was modified by Willmann (1986) to specifically state that species are reproductively isolated and originate via a stem species branching off into two new species.

What was the original species concept?

Biological species concept. In nineteen century the first who produced the most quoted definition of what he called “biological species” was the zoologist Mayr (1942) who defined species as: “groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups”.

Which species concept accommodates asexual?

As an example, a species that is a parasite may be defined in part by its adaptations to a specific organism. This concept accommodates asexual and sexual species. The paleontological species concept focuses on morphologically discrete species known only from the fossil record.

Which species concept is most applicable?

The most common species concept in the biological literature is Mayr’s [1970] Biological Species Concept. The Biological Species Concept defines a species taxon as a group of organisms that can successfully interbreed and produce fertile offspring.

Why can’t different species breed?

The biological species concept defines organisms as being, or not being, of the same species based on whether they can interbreed to make fertile offspring. Broadly speaking, different species are unable to interbreed and produce healthy, fertile offspring due to barriers called mechanisms of reproductive isolation.

What happens if a human and an animal mate?

If a human mates with another species it is very unlikely that there would be any offspring: the egg and sperm would most likely not join together. And even if they did the offspring would probably be infertile. Essentially, anatomically, the reproductive organs of the human and that of animal are not compatible.

Can a Jaguar mate with a leopard?

When the fertile offspring of a male lion and female jaguar mates with a leopard, the resulting offspring is referred to as a leoliguar.

Can a dog and cat mate?

Mating Instincts Dogs and cats can and will mate with their siblings once they are sexually mature. Litter mates are not off limits to other dogs and cats, even though they are related.

Can a cat mate with a lion?

Without quoting any experts, common sense dictates that domestic cats cannot, or should not on ethical grounds, mate with a lion or tiger or any other big cat species for several reasons. Firstly, their size difference is too large to make it practical.

Can a dog and wolf mate?

Yes, wolves and domestic dogs can breed and produce fertile offspring.

Can dogs mate with foxes?

A fox cannot breed with a dog. They do not share a compatible number of chromosome pairs, or genetic materials needed to interbreed. Science has not documented a single case of hybridization between a fox and a dog.

Can a dog and coyote mate?

Coyotes and dogs are related, and they are biologically capable of producing hybrid litters. Coyotes are highly seasonal breeders; dogs are not. Coydog females have a shifted estrus cycle that does not coincide with the coyote period. Domestic dog and coydog males do not tend to litters, whereas male coyotes do.

Can a fox breed with a cat?

No, foxes and cats can not breed. Foxes are not from the same family as cats, and do not possess the chromosomes to breed with felines.

Can a dog mate with other animals?

Dogs and coyotes are genetically similar enough to reproduce. However, their offspring are infertile, which means they cannot reproduce. All dogs of all breeds can breed with each other. They just produce another adorable four-legged friend for the world to love.

Why dogs get stuck during mating?

Dogs get stuck during mating because of a process called a copulatory tie. The male dog has an organ called the bulbus glandis, which is responsible for keeping him tied up with the female. The dog breeding tie basically keeps the semen secured inside the female dog.

Can a dog breed with a pig?

Mating. It is certainly true that pigs and dogs are sometimes willing to mate. She successfully suckled the pig, and when he grew up to be a boar, he would have nothing to do with other pigs and was treated as a dog by his owners.

What animals mate like humans?

Along with the common chimpanzee, the bonobo is the closest extant relative to humans. [4] Because the two species are not proficient swimmers, the formation of the Congo River 1.5–2 million years ago possibly led to the speciation of the bonobo.