Wiktionary species pp move indef Other uses Biological classification In biology , a species is one of the basic units of biological classification and a taxonomic rank . A species is often defined as a group ... species into infraspecific taxa such as subspecies and in botany other taxa are used, such as Variety botany varieties , subvarieties, and formae . Species that are believed to have the same ancestors are grouped together, and this group is called a genus . A species will be placed in only one genus ... , dubious reason a tiny DNA difference can divide species relatively large differences can occur between different individuals of the same species date March 2012 but for practical reasons, other properties are used. All species are given a binomial nomenclature two part name , a binomial name . The first part of a binomial name is the name of a biological genus generic name , the genus of the species ... in zoology . For example, Boa constrictor is one of four species of the Boa genus Boa genus. The first ... in italics. A usable definition of the word species and reliable methods of identifying particular species are essential for stating and testing biological theories and for measuring biodiversity ... 20106856 pmc 2936204 ref Extinct species known only from fossils are generally difficult to assign ... of non bacterial species in the world has been estimated at 8.7 million, ref name Guardian Cite news date 2011 08 23 title Planet Earth is home to 8.7 million species, scientists estimate url http www.guardian.co.uk environment 2011 aug 23 species earth estimate scientists accessdate 2011 08 23 postscript ... How Many Species Are There, Anyway? url http www.sciencedaily.com releases 2003 05 030526103731.htm ... species and reliable methods of identifying particular species is essential for stating and testing ... species must be studied for unifying characters before it can be regarded as a species. It is generally difficult to give precise taxonomic rankings to extinct species known only from fossils. Some ... more details
This is a list of lists of species . Expand list date August 2011 List of Anthurium species List of Drosera species List of Geum species List of Gymnopilus species Lists of Linyphiidae species List of mantis genera and species List of Oenothera species List of Orchidaceae species List of Quercus species List of Ranunculus species List of shark species List of Triaenonychidae species List of Utricularia species List of whitefly species See also Lists of animals Lists of IUCN Red List endangered species List of extinct species List of fictional species Category Biology Category Lists of lists ... more details
Wiktionary speciesSpecies is one of the basic units of biological classification. Species may also refer to Chemical species , a common name for atoms, molecules, molecular fragments, ions, etc. Species problem , a mixture of difficult, related questions that often come up when biologists identify species Combinatorial species , an abstract, systematic method for analysing discrete structures in terms of generating functions Counterpoint Species counterpoint Species counterpoint , a relationship between two or more voices in music Species film , a science fiction horror film Species II , the sequel Species III , a direct to video sequel Species The Awakening Species The Awakening , another direct to video sequel Species , the forms bread and wine of the Eucharist , especially in discussion of transubstantiation See also Specie disambiguation , an unrelated term used to refer to coins disambig cs Druh de Species es Especie desambiguaci n ko it Species hu Faj egy rtelm s t lap nl Species pt Esp cie desambigua o ro Specie dezambiguizare sk Druh sr fi Species sv Species ... more details
Dominant species may mean Dominant species ecology , one of a small number of species which dominate in an ecological community Dominant Species novel Dominant Species novel by Michael E. Marks Dominant Species video game Dominant Species video game Dominant Species album Dominant Species album , an album by New Zealand singer King Kapisi Disambig ... more details
Wildlife species may refer to A taxonomic species found in the wild Evolutionary Significant Unit , a grouping used in conservation which may refer to species, subspecies, or other groups disambig ... more details
In wildlife conservation , Species of Concern is an informal term, not defined in the federal Endangered Species Act . The term commonly refers to species that are declining or appear to be in need of concentrated conservation actions. Many agencies and organizations maintain lists of these at risk species. External links http www.nmfs.noaa.gov pr species concern The National Marine Fisheries Species of Concern page Category Conservation in the United States Category United States Fish and Wildlife Service ... more details
A Species affinis Affinis , abbreviations sp. aff. , Aff. , or Affin. is a species related to but not identical with the named species. ref cite web url http www.cactus art.biz note book Dictionary Dictionary S dictionary species affinis.htm title Species affinis Affinis work Dictionary of botanic terminology publisher cactus art.biz accessdate 2010 12 13 ref References reflist DEFAULTSORT Species Affinis Category Taxonomy Biology stub ... more details
The Female of the Species may refer to The Female of the Species Kipling poem , first published in 1911 The Female of the Species play , a comic play written by Joanna Murray Smith and produced in the West End, London, in 2008 Female of the Species , a 1996 song by Space English band The Female of the Species Tales of Mystery and Suspense , an anthology edited by Joyce Carol Oates Female of the Species & Female of the Species Vol2, A 2cd compilation series from Law & Auder Records featuring female electronic musicians from around the world The Female of the Species is More Deadly Than the Male is also the title of volume 38 of the comic series The Boys comics The Boys Disambig ... more details
Unreferenced date December 2009 File Kelp forest.jpg thumb Californian kelp forest In ecology , a foundation species is a dominant primary producer in an ecosystem both in terms of abundance and influence. Examples include kelp in kelp forest s and coral s in coral reef s. See also div style float right portalbox Ecology Biology Environment div Keystone species Indicator species Flagship species Ecological facilitation modelling ecosystems DEFAULTSORT Foundation Species Category Ecology Ecology stub fr Esp ce fondatrice uk ... more details
A species complex is a group of closely related species, where the exact demarcation between species is often unclear or cryptic owing to their recent and usually still incomplete reproductive isolation . Ring species , superspecies and cryptic species complex are example of species complex. Such groups of species with complex relationship between species may occur in a line undergoing rapid speciation or where such speciaton recently have occurred, so that species separation mechanisms has yet to be fully developed. Such cases may leave some species paraphyletic at the species level and to hybrid speciation hybrid species , making phylogeny phylogenetic analysis difficult. Species complexes are more common among plants , but animal examples exist, such as the dog wolf coyote complex the genus Canis and the cobras genus Naja . Often such complexes only become evident when a new species is introduced into the system, breaking down existing species barriers. An example is the introduction of Spanish slug in Northern Europe , where interbreeding with the local black slug and red slug , traditionally considered clearly separate species that did not interbreed, shows these may actually be subspecies of the same species. ref da icon Engelke, S. 2006? Til Snegleforeningen Note to the Danish Slug society . http www.dansksnegleforening.dk Af 20Sabine 20Engelke.htm Article in Danish ref Examples of known species complexes Animals The wolf dog coyote dingo group, genus Canis The cobras, genus Naja Some species of the roundback slugs, genus Arion gastropod Arion The jellyfish genus Cyanea jellyfish Cyanea , with from 1 to 14 species, depending on author. References reflist speciation Category Speciation Category Evolutionary biology no Artskompleks ... more details
Species richness is the number of different species represented in a set or collection of individuals. Species richness is simply a count of species, and it does not take into account the Abundance ecology abundances of the species or their Relative species abundance relative abundance distributions . In contrast, species diversity takes into account both species richness and species evenness . Sampling considerations Depending on the purposes of quantifying species richness, the individuals can ... been defined, its species richness can be exactly quantified, provided the species level taxonomy of the organisms of interest is well enough known. Applying different Speciesspecies delimitations will lead to different species richness values for the same set of individuals. In practice, people are usually interested in the species richness of areas so large that not all individuals in them can be observed and identified to species. Then applying different Sample statistics sampling methods will lead to different sets of individuals being observed for the same area of interest, and the species ... a species that was not yet represented in the set, and thereby increase the species richness of the set. For this reason, sets with many individuals can be expected to contain more species than sets with fewer individuals. If species richness of the obtained sample is taken to represent species richness ..., 345, 101 118. ref Properties of the sample, especially the number of species only represented by one or a few individuals, can be used to help estimating the species richness in the population from ... in a population. Scandinavian Journal of Statistics, 11, 265 270. ref ref Chao, A. 2005 Species richness ... of Statistical Sciences. New York, Wiley. ref Trends in species richness The observed species richness ... are drawn from different environmental conditions or different habitats , the species ... environments. The accumulation of new species with increasing sampling effort can be visualised ... more details
About an ecological term Common disambiguation Definitions Common species and uncommon species are designations used in ecology to describe the population status of a species. Commonness is closely related to abundance ecology abundance . Abundance refers to the frequency with which a species is found in controlled samples in contrast, species are defined as common or uncommon based on their overall presence in the environment. A species may be locally abundant without being common. However, common and uncommon are also sometimes used to describe levels of abundance, with a common species being less abundant than an abundant species, while an uncommon species is more abundant than a rare species. ref cite web url http www.npwrc.usgs.gov resource birds stcroix methods.htm work Birds of the St. Croix River Valley Minnesota and Wisconsin title Methods, Terminology, and Nomenclature author Northern Prairie Wildlife Research Center accessdate 2006 12 31 year 2006 ref Common species and conservation Common species are frequently regarded as being at low risk of extinction simply because they exist in large numbers, and hence their conservation status is often overlooked. While this is broadly logical, there are several cases of once common species being driven to extinction such as the Passenger Pigeon and the Rocky Mountain locust , which numbered in the billions and trillions respectively before their demise. Moreover, a small proportional decline in a common species results in the loss of a large number of individuals, and the contribution to ecosystem function that those individuals represented. A recent paper argued that because common species shape ecosystems, contribute disproportionately to ecosystem functioning, and can show rapid population declines, conservation should look more closely at how the trade off between species extinctions and the depletion of populations ... DOI 10.1016 j.tree.2007.11.001 ref . Notes references See also Rare species Abundance ecology Category ... more details
Umbrella species are species selected for making wildlife conservation conservation related decisions, typically because protecting these species indirectly protects the many other species that make up the ecological community ecology community of its habitat . Species conservation can be subjective because it is hard to determine the status of many species. With millions of species of concern, the identification of selected keystone species , flagship species or umbrella species makes conservation decisions easier. Umbrella species can be used to help select the locations of potential reserves ... of the Umbrella Species Concept as a Conservation Tool. Conservation Biology , Vol. 18, No. 1, 76 85 ref Definitions Two commonly used definitions A A wide ranging species whose requirements include those of many other species ref Groom, Martha J., Gary K. Meffe and C. Ronald Carroll. 2006. Principles of Conservation Biology. Sunderland, Massachusetts, Sinauer Associates, Inc. ref B A species with large area requirements for which protection of the species offers protection to other species that share ... and Kenji Fukuyama. 2006. A Mechanistic Approach to Evaluation of Umbrella Species as Conservation ... of umbrella species automatically extends protection to other species. i.e. spotted owl ... species, relatively large bodied and wide ranging species of higher vertebrates ref name launer1994 Launer, Alan E. and Dennis D. Murphy. 1994. Umbrella Species and the Conservation of Habitat Fragments ... , Vol. 69, No. 2, 145 153. ref Use in landuse management The use of umbrella species as a conservation ... Miller, Smithsonian Institution Press, pp. 18 30. ref who defined an umbrella species as one whose ... that a combination of other tools establish better land management reserves to help protect more species than just using umbrella species alone. Individual invertebrate species can be good umbrella species because they can protect older, unique ecosystems. There have been cases where umbrella species ... more details
Cleanup date April 2010 An Adventive species is one that has arrived in the geographical area specified from somewhere else by any means i.e. through imported plants , but is not self sustaining and whose numbers are only increased through non reproductive means, unlike a Naturalisation biology naturalised species . See also Naturalisation biology Introduced species Invasive species Weed DEFAULTSORT Adventive Species Category Introduced species Category Ecological processes Category Environmental conservation Category Habitat ecology terminology Ecology stub sv Adventivv xt ... more details
refimprove date March 2011 In biological nomenclature , a type species is both a concept and a practical system which is used in the classification and nomenclature naming of animals and plants. The value of a type species lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species to which the name of a genus is permanently linked it is the species that contains the biological Type biology type specimen s of the taxon . This is an important concept whenever a taxon containing multiple species must be divided into more than one genus the type species automatically assigns the name of the original taxon to one of the resulting new taxa, thus reducing ... or correct name botany correct , should have a type species. In practice however there is a backlog ... . In zoology see also Types in zoology The term type species is regulated in zoological nomenclature by article 42.3 of the International Code of Zoological Nomenclature , which defines a type species ... species . In the Glossary, type species is defined as The nominal species that is the name bearing type of a nominal genus or subgenus . The type species permanently attaches a genus biology genus to its formal name its generic name by providing just one species within that genus to which the genus is permanently linked i.e. the genus must include that species if it is to bear the name . The species name in turn is fixed, in theory, to a type specimen. For example, the type species for the land ... Hygromiidae . The type genus for that family is the genus Hygromia . The concept of the type species ... of a genus , its type will usually be the type for a species included within it and can be indicated by the name of this species alone. ref ICBN Art 10.1 Vienna Code, 2005 ref The term type species , although of no formal standing under the Code, is sometimes borrowed from zoological nomenclature. See also Type biology References Reflist DEFAULTSORT Type Species Category Taxonomy Type ... more details
Infobox journal title Mammalian Species cover discipline Mammalogy website http www.science.smith.edu departments Biology VHAYSSEN msi publisher American Society of Mammalogists country United States abbreviation Mamm. Species history 1969 present ISSN 0076 3519 eISSn 1545 1410 OCLC 46381503 LCCN 2004204506 CODEN MLNSBP JSTOR 00763519 Mammalian Species is a Peer review peer reviewed scientific journal published by the American Society of Mammalogists . The journal publishes accounts of 25 35 mammal species yearly. The articles summarize the current literature about each mammal and its systematics , genetics , fossil history, distribution, anatomy , physiology , behavior, ecology , and conservation is described. The journal was established in 1969. External links Official http www.science.smith.edu departments Biology VHAYSSEN msi biology journal stub Category Zoology journals Category Publications established in 1969 de Mammalian Species el Mammalian Species pl Mammalian Species ... more details
A species group is an informal taxonomic rank into which an assemblage of closely related species within ... ref ref name oxford http www.encyclopedia.com doc 1O8 speciesgroup.html Michael Allaby. species group ... etd 10272008 31295014212541 Molecular systematics of the Peromyscus boylii species group ref Use The use ... sufficient differentiation to be recognized as separate species but possess inadequate variation to be recognized as subgenera . Defining species groups is a convenient way of subdividing well defined genera with a large number of recognized species. The use of species groups have enabled systematists to consolidate polytypic polytypic speciesspecies into Biological classification nominal species which in turn can be grouped into the larger array of the species group. ref name etd Range In regards to whether or not members of a species group share a Range biology range , sources differ. A source from Iowa State University Department of Agronomy says that members of a species group usually ... of Zoology Oxford University Press 1999 describes a species group as complex of related species that exist ... crosses in which only certain pairs of species will produce Hybrid biology hybrids . ref name oxford The examples given below may support both uses of the term species group. Arthropod examples The Drosophilidae fruit fly subgenus Sophophora contains the Drosophila melanogaster species group Drosophila melanogaster species group which itself contains 12 subgroups. The Drosophila obscura species group Drosophila obscura species group belongs to the same subgenus and contains 6 subgroups ... in the Drosophila melanogaster species group journal PLoS Biol. volume 5 issue 6 pages e152 year ... of wasp s, only a few species have a scavenger scavenging Habit biology habit as opposed to a strictly ... of these are the three species belonging to the Vespula vulgaris species group which includes the common ... to the Gracilis species group . All of the species in this group are characterized by their long, narrow ... more details
Victoria of Great Britain Living creatures are classified into species , which are in turn classified .... To date, approximately Encyclopedia of life 1.9 million species have been discovered and named. This number is still an estimate as so far there is no central registration of species, although ZooBank efforts are underway to establish such a species register. The actual number of species existing on earth ... species are continually being discovered. In 2010, it is estimated that ref name 2010newspecies cite ... of 18225 new live species 2140 fossil species and a cool top 10 list title Geology Global Network ref 18,225 new species were discovered and scientifically described plus an additional 2,140 fossil species presumed extinct . Naming of a new species When a creature is discovered, it is first necessary to determine whether it is a new species, a new subspecies or merely a variant of an already described and known species. As there is Species problem no single, unambiguous definition of species ..., the right to name a new species is given to the discoverer, or more precisely the scientific describer of the species who is not necessarily the person who discovered the species in nature . There are, however, many regulations to be followed when naming a species, all of them fixed by the International ... established 1758 by Carl von Linn and each scientific species name is a composite of Binominal nomenclature two parts , namely the genus name and the species name. For example, the scientific name of the European Common Frog is Rana temporaria , where Rana is the genus name and temporaria is the species name. As the genus name should reflect relationships among different species within the same ... of new genera, the genus name is fixed already, whereas the species name may be freely chosen by the scientic describer of the species within the frame of the ICZN or ICBN regulations. Naming process A name of a new species becomes valid with the date of publication of its formal scientific ... more details
Multiple issues in universe March 2009 unreferenced December 2006 inappropriate tone December 2007 The Species in the movie Species film Species is an unnamed, aggressive alien species intent on spreading itself throughout the universe by infiltrating and annihilating the intelligent populations of other planets. It is capable of rapid growth and can bond its own DNA to that of other creatures through a number of methods. They are apparently inspired by the mythological succubus and incubus , who were demons who seduced their victims to have sexual intercourse with them. Origins In Species II a professor named Herman Cromwell, played by Peter Boyle , claims that the original species originated ... from another planet came to visit so that their species could continue to infect other planets in a similar manner. Mankind s first interaction with this particular species occurred in 1994 when the SETI ... Sil . Physical appearance and growth The Species appear to be sexually dimorphic with males being ... forms and appearing to be much more agile. Both genders of the Species have skeletal bodies with proportionally ... whether the Species is patriarchal or matriarchal within its own social circles as a population of sufficient size has never been observed in the movies. Most of the members of the Species seen are actually ... of life, it was killed by immolation. In the film novelization of Species , the pure creature was actually .... The most prominent example of a mutation induced by the species was that of Sil . Sil grew into a visible ... of technological achievement The Species are currently at. However, their mentioned mastery of black ..., the Species have not been shown to have space travel capabilities although, in a rejected Species .... In the movie novelization of Species II , the Species had once established a colony on Mars and consumed ... and there is no mention of Spaceflight space travel . However, a character speculates that the Species ... use. Species Films DEFAULTSORT Species Alien Species Category Species films Category Fictional species ... more details
Sibling species are species that are very similar in appearance, in behavior and in other characteristics, but they are Reproductive isolation reproductively isolated . In other words, sibling species also known as aphanic species are pairs or groups of genetically closely related species which are often morphologically indistinguishable, but are reproductively isolated , meaning that while they may interbreed , the offspring cannot reproduce. ref R.J. Lincoln, G.A. Boxshall, and P.F. Clark, A Dictionary of Ecology, Evolution and Systematics 1982 , Cambridge University Press, p. 227. ISBN 0 521 23957 5. ref Sibling species may arise as a result of allopatric speciation through geographic isolation , parapatric speciation , or sympatric speciation . The important thing to note is that sibling species are in fact separate biological species . The Biological Species Concept, proposed by Ernst Mayr in 1942, emphasizes reproductive isolation as the basis of defining a species. ref Mayr, Ernst 1970 . Populations, Species, and Evolution. The Belknap Press of Harvard University Press, Cambridge, MA, at p. 13. ISBN 0 674 69013 3. http books.google.com ?id STEXkujeBnsC&pg PA1&dq mayr e v onepage&q mayr 20e&f false. Retrieved 12 11 2010. ref The definition states A species is defined as a population ... species. Mayr, a proponent of allopatric speciation , hypothesized that adaptive genetic changes ... s, resulting in Infertility sterility of the offspring. ref Mayr, Ernst 1970 . Populations, Species ... 12 11 2010. ref Until recently, scientists deemed pairs or groups of species as sibling species ... and molecular phylogeny have made it possible to better determine whether two or more species are in reality sibling species. ref Puillandre N., Meyer C.P., Bouchet P. & Olivera B.M., Genetic divergence ... Scripta 2011 40 4 350 363. ref References references See also Biological species Allopatric speciation ... Category Speciation ca Esp cies bessones de Zwillingsart es Especies gemelas it Sibling species ... more details
Climax species , also called late Sere ecology seral , late successional , K selected or equilibrium species, are plant species that will remain essentially unchanged in terms of species composition for as long as a site remains undisturbed. They are the most Shade tolerance shade tolerant species of tree to establish in the process of Ecological succession forest succession . The seedling s of climax species can grow in the shade of the parent trees, ensuring their dominance indefinitely. A Disturbance ecology disturbance such as fire may kill the climax species, allowing pioneer species pioneer or earlier successional species to re establish for a time. They are the opposite of pioneer species , also known as ruderal species ruderal , fugitive, opportunistic or R selected species, in the sense that climax species are good competitors but poor colonizers, whereas pioneer species are good colonizers but poor competitors. Climax species dominate the climax community , when the pace of succession ... adaptive characteristics can be considered more sophisticated than those of opportunistic species. Through negative feedback , they adapt themselves to specific environmental conditions. Climax species, closely controlled by carrying capacity , follow K strategy K strategies , wherein species produce ... of each one to the micro environmental conditions of its specific ecological niche . Climax species ... Relationships Among Species ref Disputed Term The idea of a climax species has been criticized in recent ... species is still widely used in Silviculture silvicultural programs and California Department ... White spruce Picea glauca is an example of a climax species in the northern forests of North America .... Whitmore. On the definition of ecological species groups in tropical rain forests . Plant Ecology .... Turing instability in pioneer climax species interactions . October 2004. http dx.doi.org 10.1016 j.mbs.2004.10.010 Science Direct . DEFAULTSORT Climax Species Category Ecological succession Category ... more details
Image EDGE of Existence logo.png right 200px Evolutionarily Distinct and Globally Endangered EDGE species ... and are often extremely unusual in the way they look, live and behave. Some EDGE species, such as elephants ... indicates that 70 of the world s most threatened and evolutionarily distinct mammal species are currently ... 10.1371 journal.pone.0000296 url http dx.plos.org 10.1371 journal.pone.0000296 ref If these species are not highlighted and conserved we will not only lose many of the world s unique species and a disproportionate ... of Existence Programme to raise awareness and funds for the conservation of these species. Calculating EDGE Scores Image Edge tree.gif right Every species is given a score according to the amount ... EDGE species. Some species are more distinct than others because they represent a larger amount of unique evolution. Species like the aardvark have few close relatives and have been evolving ... many close relatives. Species uniqueness can be measured as an Evolutionary Distinctiveness ED score, using a phylogeny, or evolutionary tree. In the phylogeny shown on the right, species A has a higher ED score than either species B or C it represents a branch rather than a twig on the tree of life. If species A were to go extinct, there would be no similar species left on the planet and a disproportionate ... scores for each species are measured according to the IUCN Red List of Threatened Species, an assessment of the conservation status of the world s plant and animal species. div style float left border ... Red List categories. div Species which are Critically Endangered receive a higher score than less threatened species, which in turn, receive a higher score than those not currently in danger of extinction. The two scores are then combined to produce an overall EDGE score for each species. EDGE scores ... of the expected loss of evolutionary history per unit time. EDGE species are species which have ... . There are currently 564 EDGE mammal species 12 of the total . Potential EDGE species are those ... more details
Rquote right ... I was much struck how entirely vague and arbitrary is the distinction between species and varieties Charles Darwin On the Origin of Species p. 48 ref name darwin1859 cite book last Darwin first C. authorlink Charles Darwin year 1859 title On the origin of species by means of natural selection publisher Murray location London isbn 8420656070 ref The species problem is a mixture of difficult, related questions that often come up when biologist s define the word species . Definitions ... meaning of the phrase species problem is quite different from what was meant by species ... Robson first G. C. year 1928 title The Species Problem an Introduction to the Study of Evolutionary Divergence in Natural Populations publisher Oliver and Boyd location Edinburgh ref For Darwin the species problem was the question of speciation how new species arose . One common but sometimes difficult question is how best to decide just which particular species an organism belongs to. Dubious reason I ve never seen it suggested that this is part of the species problem date March 2012 Another challenge is deciding when to recognize a new species, for example when new data indicate that one previously described species actually may include two or more separately evolution evolving groups, each of which could possibly be recognized as a separate species. Many of the debates on species touch ... of language and cognitive cognition . Confusion on the meaning of SpeciesSpecies is one of several ... , and the system of classification includes, in addition to species the ranks of genus and Family biology family and others all the way up to Kingdom biology kingdom . Usually the rank of species is the basal rank , meaning that in the system of scientific classification species is the bottommost rank that includes no other ranks. However sometimes when one species, that is already named and described ... the rank of subspecies . Even though it is not disputed that species is a taxonomic rank, this does ... more details
Chemical species are atom s, molecule s, molecular fragments, ion s, etc., being subjected to a chemical process or to a measurement . ref http www.iupac.org goldbook C01038.pdf IUPAC Gold Book definition of chemical species ref Generally, a chemical species can be defined as an ensemble of chemically identical molecular entity molecular entities that can explore the same set of molecular energy levels on a characteristic or delineated time scale. The term may be applied equally to a set of chemically identical atomic or molecular structural units in a solid array. In supramolecular chemistry , chemical species are those supramolecular structures whose interactions and associations are brought about via intermolecular bonding and debonding actions, and function to form the basis of this branch of chemistry. References references See also List of particles Category Chemistry chem stub ar ca Esp cie qu mica de Spezies Chemie es Especie qu mica fr Esp ce chimique it Specie chimica he pt Esp cie qu mica simple Chemical species sr Hemijska vrsta sv Species kemi ... more details
Species diversity is the effective number of different species that are represented in a collection of individuals a dataset . The effective number of species refers to the number of equally abundant species needed to obtain the same mean proportional species abundance as that observed in the dataset of interest where all species may not be equally abundant . Species diversity consists of two components, species richness and species evenness . Species richness is a simple count of species, whereas species evenness quantifies how equal the Abundance ecology abundances of the species are. ref name .... 2010. A consistent terminology for quantifying species diversity? Yes, it does exist. Oecologia 4 853 860. doi 10.1007 s00442 010 1812 0 ref Calculation of diversity Species diversity in a dataset can be calculated by first taking the weighted average of species proportional abundances in the dataset ... mathematics denominator equals mean proportional species abundance in the dataset as calculated ... of speciesspecies richness in the dataset, and the proportional abundance of the i th species is math ... kind of mean is used. q 0 corresponds to the harmonic mean , and gives values equal to species richness ... i math value. In practice, q modifies species weighting, such that increasing q increases the weight given to the most abundant species, and fewer equally abundant species are hence needed to reach mean proportional abundance. Consequently, large values of q lead to smaller species diversity than small values of q for the same dataset. If all species are equally abundant in the dataset, changing the value of q has no effect, but species diversity at any value of q equals species richness. Negative values of q are not used, because then the effective number of species diversity would exceed the actual number of species richness . As q approaches negative infinity, the generalized mean approaches the minimum math p i math value. In many real datasets, the least abundant species is represented ... more details
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