View source for Biology:Glossary of speciation

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This '''glossary of speciation''' is a list of definitions of terms and concepts used in the study of [[Biology:Speciation|speciation]] and related disciplines in [[Biology:Evolutionary biology|evolutionary biology]]. It is intended as introductory material and a structured organization of the often complex language used in the literature. For additional terms from related glossaries, see Glossary of biology, [[Biology:Glossary of genetics|Glossary of genetics]], and [[Earth:Glossary of ecology|Glossary of ecology]].

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{{glossary}}

==A==
{{term|agamospecies}}
{{defn|A species that does not reproduce sexually but instead by cloning.<ref>{{Citation|author=Oxford Reference |title=agamospecies |publisher=Oxford University Press |date=2008 |url= }}</ref> Agamospecies are sometimes represented by [[Biology:Species complex|species complex]]es that contain some [[Biology:Ploidy|diploid]] individuals and other [[Biology:Apomixis|apomitic forms]]—in particular, plant species that can reproduce via agamospermy.<ref name="Coyne&Orr2004">{{Citation | title=Speciation | author1=Jerry A. Coyne |author1link=Jerry Coyne |author2=H. Allen Orr |author2link=H. Allen Orr | date=2004 | pages=1–545 | publisher=Sinauer Associates | isbn=978-0-87893-091-3 }}</ref>}}

{{term|allochronic isolation}}
{{defn|Isolation of two populations of a species due to a change in breeding periods. This isolation acts as a precursor to '''allochronic speciation''', speciation resulting from two populations of a species that have become isolated due to differences in breeding periods. An example is the periodical 13- and 17-year ''[[Biology:Magicicada|Magicicada]]'' species.<ref name="Coyne&Orr2004"/>}}

{{term|allo-parapatric speciation}}
{{defn|A mode of speciation where divergence occurs in allopatry and is completed upon [[Biology:Secondary contact|secondary contact]] of the populations--effectively a form of [[Biology:Reinforcement (speciation)|reinforcement]].<ref>{{Citation |title=Sympatric speciation in animals: new wine in old bottles |author=Guy L. Bush |journal=Trends in Ecology & Evolution |year=1994 |volume=9 |issue=8 |pages=285–288 |doi=10.1016/0169-5347(94)90031-0|pmid=21236856 }}</ref><ref name="Coyne&Orr2004"/>}}

[[File:Allopatric Speciation Schematic.svg|right|thumb|upright=1.3|In allopatric speciation, a population becomes separated by a geographic barrier. [[Biology:Reproductive isolation|Reproductive isolation]] evolves, resulting in two separate species.]]
{{term|[[Biology:Allopatric speciation|allopatric speciation]]}}
{{defn|A mode of speciation where the evolution of reproductive isolation is caused by geographic separation of a species population.<ref name="eLS2003">{{cite book | last =Howard | first =Daniel  J. | title =Speciation: Allopatric  | journal =eLS | date =2003 | doi =10.1038/npg.els.0001748| isbn =978-0470016176 }}</ref> Also called '''geographic speciation''', '''vicariance''',  '''vicariant speciation''', or '''dichopatric speciation'''.}}

{{term|allopatric taxa}}
{{defn|Specific species that are allopatrically distributed.}}

{{term|allopatry}}
{{defn|Species populations that exist geographically separated from one another.}}

{{term|allopolyploid}}
{{defn| }}

{{term|allo-sympatric speciation}}
{{defn|A mode of speciation where divergence occurs in allopatry and is completed upon [[Biology:Secondary contact|secondary contact]] of the populations--effectively a form of [[Biology:Reinforcement (speciation)|reinforcement]].<ref name="Guy L. Bush 1994 285–288">{{Citation |title=Sympatric speciation in animals: new wine in old bottles | author=Guy L. Bush | journal=Trends in Ecology & Evolution | year=1994 | volume=9 | issue=8 | pages=285–288 | doi=10.1016/0169-5347(94)90031-0| pmid=21236856 }}</ref><ref name="Coyne&Orr2004"/>}}

{{term|[[Biology:Anagenesis|anagenesis]]}}
{{defn|[[Biology:Evolution|Evolution]]ary change that occurs within a species lineage as opposed to lineage splitting ([[Biology:Cladogenesis|cladogenesis]]).<ref name="Vauxetal2016">{{cite journal |title=Lineages, splits and divergence challenge whether the terms anagenesis and cladogenesis are necessary |journal=Biological Journal of the Linnean Society |volume=117 |issue=2 |pages=165–76 |year=2016 |last1=Vaux |first1=Felix |last2=Trewick |first2=Steven A. |last3=Morgan-Richards |first3=Mary |doi=10.1111/bij.12665}}</ref>

{{term|area cladogram}}
{{defn| }}

{{term|[[Biology:Assortative mating|assortative mating]]}}
{{ghat|Also called '''positive assortative mating''' and '''homogamy'''.}}
{{defn|A {{gli|mating system}} in which individuals with similar {{gli|phenotype|phenotypes}} [[Biology:Mating|mate]] with each other more frequently than would be expected in a completely random mating system. Assortative mating usually has the effect of increasing genetic relatedness between members of the mating population. Contrast ''{{gli|disassortative mating}}''.}}

{{term|autoallopolyploid}}
{{defn| }}

{{term|autopolyploid}}
{{defn| }}

==B==
{{term|bacterial speciation}}
{{defn| }}

{{term|barrier}}
{{defn| }}

{{term|behavioral isolation}}
{{defn| }}

{{term|[[Earth:Biogeography|biogeography]]}}
{{defn|The scientific study of the spatial distributions of species. It includes the study of both extinct and extant organisms.<ref>{{Citation |title=Biography |edition=2 |author=M. V. Lomolino & J. H. Brown |date=1998 |pages=[https://archive.org/details/biogeography0000brow/page/3 3] |publisher=Sinauer Associates, Sunderland, MA. |isbn=978-0-87893-073-9 |url=https://archive.org/details/biogeography0000brow/page/3 }}</ref>}}

{{term|biological species concept}}
{{defn| }}

{{term|bottleneck}}
{{defn| }}

==C==
[[File:Centrifugal Speciation Schematic.svg|right|thumb|upright=1.3|In centrifugal speciation, an original population (green) range expands and contracts, leaving an isolated fragment population behind. The central population (changed to blue) evolves reproductive isolation.]]
{{term|centrifugal speciation}}
{{defn|A variation of peripatric speciation where speciation occurs by geographic isolation, but reproductive isolation evolves in the larger population instead of the peripherally isolated population.<ref name="Gavrilets">{{Citation |title=Patterns of Parapatric Speciation | author=Sergey Gavrilets|display-authors=0 | journal=Evolution | year=2000 | volume=54 | issue=4 | pages=1126–1134 | doi=10.1554/0014-3820(2000)054[1126:pops]2.0.co;2}}</ref>}}

{{term|[[Biology:Chimera (genetics)|chimera]]}}
{{defn| }}

{{term|chromosomal speciation}}
{{defn| }}

{{term|[[Biology:Chronospecies|chronospecies]]}}
{{defn| }}

{{term|[[Biology:Cladogenesis|cladogenesis]]}}
{{defn|The splitting of a species lineage into multiple lineages.<ref name="Vauxetal2016"/>}}

{{term|[[Biology:Cline|cline]]}}
{{defn| }}

{{term|cluster analysis}}
{{defn| }}

{{term|clustering}}
{{defn| }}

{{term|[[Biology:Character displacement|character displacement]]}}
{{defn| }}

{{term|cohesion species concept}}
{{defn| }}

{{term|colonization}}
{{defn| }}

{{term|competitive gametic isolation}}
{{defn| }}

{{term|congruent clines}}
{{defn| }}

{{term|copulatory behavioral isolation}}
{{defn| }}

{{term|coupling}}
{{defn| }}

{{term|[[Biology:Cospeciation|cospeciation]]}}
{{defn|Cospeciation is a form of speciation where more than species speciation concurrently due to their ecological associations (e.g. host-parasite interactions).<ref>{{cite book | last =Page | first =Roderick DM. | title =Cospeciation  | journal =eLS | date =2006 | doi =10.1038/npg.els.0004124
| isbn =978-0470016176 }}</ref>}}

{{term|cyptic species}}
{{defn| }}

{{term|cytoplasmic isolation}}
{{defn| }}

==D==
{{term|directional speciation}}
{{defn| }}

{{term|[[Biology:Assortative mating|disassortative mating]]}}
{{ghat|Also called '''negative assortative mating''' and '''heterogamy'''.}}
{{defn|A {{gli|mating system}} in which individuals with dissimilar {{gli|phenotype|phenotypes}} [[Biology:Mating|mate]] with each other more frequently than would be expected in a completely random mating system. Disassortative mating usually has the effect of decreasing genetic relatedness between members of the mating population. Contrast ''{{gli|assortative mating}}''.}}

{{term|dispersal}}
{{defn| }}

{{term|divergence}}
{{defn|[[Biology:Phenotype|phenotypic]] or [[Biology:Genotype|genotypic]] changes that occur in two different populations or evolutionary lineages.<ref name="Vauxetal2016"/>}}

{{term|divergence-with-gene-flow}}
{{defn| }}

{{term|diversification}}
{{defn| }}

{{term|Dobzhansky-Muller model}}
{{defn| }}

{{term|''[[Biology:Drosophila|Drosophila]]''}}
{{defn|A [[Biology:Genus|genus]] of flies commonly known as fruit flies which is used extensively as a model organism in [[Biology:Genetics|genetics]] research and [[Organization:Laboratory experiments of speciation|laboratory experiments in speciation]].}}

==E==
{{term|ecogeographic isolation}}
{{defn| }}

{{term|ecological allopatry}}
{{defn| }}

{{term|ecological character displacement}}
{{defn| }}

{{term|ecological isolation}}
{{defn| }}

{{term|[[Biology:Ecological niche|ecological niche]]}}
{{defn| }}

{{term|[[Earth:Ecological speciation|ecological speciation]]}}
{{defn|A process of speciation where reproductive isolation is caused by the interaction of individuals of a species with their environment.<ref>{{Citation |title=Ecological Speciation | author=Howard D. Rundle and Patrik Nosil | journal=Ecology Letters | year=2005 | volume=8 | issue=3 | pages=336–352 | doi=10.1111/j.1461-0248.2004.00715.x }}</ref>}}

{{term|ecological species concept}}
{{defn| }}

{{term|[[Earth:Ecotone|ecotone]]}}
{{defn| }}

{{term|[[Biology:Endemism|endemism]]}}
{{defn|An ecological state of a species being unique to a defined geographic location, such as an island, nation, country or other defined zone, or habitat type.}}

{{term|environmental gradient}}
{{defn| }}

{{term|[[Biology:Epistasis|epistasis]]}}
{{defn| }}

{{term|ethological isolation}}
{{defn| }}

{{term|ethological pollinator isolation}}
{{defn| }}

{{term|[[Biology:Evolution|evolution]]}}
{{defn| }}

{{term|evolutionary lineage}}
{{defn|The line of descent of a species.<ref name="Vauxetal2016"/>}}

{{term|evolutionary species concept}}
{{defn| }}

{{term|[[Biology:Extinction|extinction]]}}
{{defn| }}

{{term|extrinsic hybrid inviability}}
{{defn| }}

{{term|extrinsic postzygotic isolation}}
{{defn| }}

==F==
{{term|[[Biology:Fitness|fitness]]}}
{{defn| }}

{{term|floral isolation}}
{{defn| }}

{{term|flowering asynchrony}}
{{defn| }}

{{term|[[Biology:Fossil|fossil]]}}
{{defn| }}

{{term|[[Biology:Founder effect|founder effect]]}}
{{defn| }}

{{term|founder event}}
{{defn| }}

{{term|founder-flush-crash}}
{{defn| }}

{{term|founder takes all}}
{{defn|A [[Hypothesis|hypothesis]] that describes the evolutionary advantages of the first-arriving lineages in a new [[Earth:Ecosystem|ecosystem]].<ref>{{cite journal |vauthors=Waters JM, Fraser CI, Hewitt GM| title = Founder takes all: density-dependent processes structure biodiversity | journal = Trends in Ecology & Evolution | volume = 28 | pp = 78–85| year = 2013 | doi=10.1016/j.tree.2012.08.024}}</ref> An example could be when a species becomes reproductively isolated on an island as in [[Biology:Peripatric speciation|peripatric speciation]].}}

==G==
{{term|gametic isolation}}
{{defn| }}

{{term|genealogical species concept}}
{{defn| }}

[[File:Gene flow (butterflies).svg|right|thumb|upright=1.3|[[Biology:Gene flow|Gene flow]] is the transfer of alleles from one population to another population through immigration of individuals.]]
{{term|[[Biology:Gene flow|gene flow]]}}
{{defn|The transfer of [[Biology:Genetic variation|genetic variation]] from one [[Social:Population|population]] to another.}}

{{term|genetic distance}}
{{defn| }}

{{term|[[Biology:Genetic drift|genetic drift]]}}
{{defn| }}

{{term|genic speciation}}
{{defn| }}

{{term|genotypic cluster species}}
{{defn| }}

{{term|geographic speciation}}
{{defn| }}

{{term|gradualism}}
{{defn|Continuous evolutionary change within a species lineage.<ref name="Vauxetal2016"/>}}

==H==
{{term|habitat isolation}}
{{defn| }}

{{term|heteropatric speciation}}
{{defn| }}

{{term|[[Biology:History of speciation|history of speciation]]}}
{{defn|The historical development concerning the thought and ideas about the biological phenomenon of speciation.}}

{{term|[[Biology:Haldane's rule|Haldane's rule]]}}
{{defn|A rule formulated by J.B.S. Haldane that states if one sex of a hybrid between two incipient species is inviable or sterile, that sex is more likely to be the [[Biology:Heterogametic sex|heterogametic sex]] (i.e. the one with two different sex chromosomes).<ref>{{cite journal |title=The Dominance Theory of Haldane's Rule|author1=Turelli, M |author2=Orr, H.A.  |journal=Genetics |date=May 1995 |volume=140 |issue=1 |pages=389–402 |pmc=1206564 |pmid=7635302}}</ref>}}

{{term|homoploid recombinational speciation}}
{{defn| }}

{{term|host race}}
{{defn| }}

{{term|host-specific parasite}}
{{defn| }}

{{term|host-specific species}}
{{defn| }}

{{term|[[Biology:Hybrid|hybrid]]}}
{{defn| }}

{{term|hybrid breakdown}}
{{defn| }}

{{term|hybrid incompatibility}}
{{defn| }}

{{term|hybrid inviability}}
{{defn| }}

{{term|hybridization}}
{{defn| }}

{{term|[[Biology:Hybrid speciation|hybrid speciation]]}}
{{defn| }}

{{term|hybrid sterility}}
{{defn| }}

{{term|hybrid swarm}}
{{defn| }}

{{term|[[Biology:Hybrid zone|hybrid zone]]}}
{{defn| }}

==I==
{{term|incomplete speciation}}
{{defn| }}

{{term|incipient species}}
{{defn|Two populations of a species in the early stage of speciation}}

{{term|interbreeding}}
{{defn| }}

{{term|intrinsic postzygotic isolation}}
{{defn| }}

{{term|introgression}}
{{defn| }}

{{term|inviability}}
{{defn| }}

{{term|isolating mechanism}}
{{defn| }}

{{term|isolation}}
{{defn| }}

{{term|[[Biology:Isolation by distance|isolation by distance]]}}
{{defn| }}

==J==
{{term|Jordan's Law}}
{{defn| }}

==K==
[[File:Kaneshiro Peripatric Speciation (process).png|right|thumb|upright=1.3|In the Kaneshiro model of peripatric speciation, a sample of a larger population results in an isolated population with less males containing attractive traits. Over time, choosy females are selected against as the population increases. Sexual selection drives new traits to arise (green), reproductively isolating the new population from the old one (blue).]]
{{term|Kaneshiro model}}
{{defn|A model of [[Biology:Peripatric speciation|peripatric speciation]] developed by Kenneth Y. Kanneshiro where a [[Biology:Sexual reproduction|sexual species]] experiences a population bottleneck—that is, when the genetic variation is reduced due to small population size—[[Philosophy:Mate choice|mating discrimination]] among females may be altered by the decrease in [[Biology:Courtship display|courtship behaviors]] or displays of males. This allows sexual selection to give rise to novel sexual traits in the new population.<ref>{{Citation |title=Sexual selection and peripatric speciation: the Kaneshiro model revisited |author=Anders Ödeen & Ann-Britt Florin |journal=Journal of Evolutionary Biology |year=2002 |volume=15 |issue= 2|pages=301–306 |doi=10.1046/j.1420-9101.2002.00378.x}}</ref>}}

==L==
{{term|lineage-splitting}}
{{defn|When genetic exchange ([[Biology:Gene flow|gene flow]] between two populations is eliminated. Also called '''lineage-branching''.<ref name="Vauxetal2016"/>}}

==M==
{{term|mating system isolation}}
{{defn| }}

{{term|mechanical isolation}}
{{defn| }}

{{term|mechanical pollinator isolation}}
{{defn| }}

{{term|microallopatric}}
{{defn|Allopatric speciation occurring on a small geographic scale.<ref>{{Citation |title=What, if anything, is sympatric speciation? | author=B. M. Fitzpatrick| author2=A. A. Fordyce| author3= S. Gavrilets | journal=Journal of Evolutionary Biology | year=2008 | volume=21 | issue=6| pages=1452–1459 | doi=10.1111/j.1420-9101.2008.01611.x | pmid=18823452}}</ref>}}

{{term|microspecies}}
{{defn| }}

{{term|migration}}
{{defn| }}

{{term|[[Biology:Modern synthesis (20th century)|modern synthesis]]}}
{{defn| }}

{{term|modes of speciation}}
{{defn|A classification scheme of speciation processes based on the level of gene flow between two populations.<ref name="Harrison2012"/> The traditional terms for the three modes—allopatric, parapatric, and sympatric—are based on the spatial distributions of a species population.<ref name="Fitzpatricketal2009">{{Citation|title=Pattern, process and geographic modes of speciation |author=B. B. Fitzpatrick, J. A. Fordyce, & S. Gavrilets |journal=Journal of Evolutionary Biology |year=2009 |volume=22 |issue=11 |pages=2342–2347 |doi=10.1111/j.1420-9101.2009.01833.x |pmid=19732257 }}</ref><ref name="Harrison2012"/>}}

{{term|morphological species concept}}
{{defn| }}

{{term|mosaic}}
{{defn| }}

{{term|mosaic hybrid zone}}
{{defn|A zone in which two speciating lineages occur together in a patchy distribution–either by chance, random colonization, or low hybrid [[Biology:Fitness|fitness]].<ref name="Harrison2012">{{Citation |title=The Language of Speciation | author=Richard G. Harrison | journal=Evolution | year=2012 | volume=66 | issue=12 | pages=3643–3657 | doi=10.1111/j.1558-5646.2012.01785.x | pmid=23206125 }}</ref>}}

{{term|mosaic sympatry}}
{{defn|A case of sympatry where two populations overlapping in geographic distribution exhibit habitat specializations.<ref name="Harrison2012"/>}}

==N==
{{term|[[Biology:Natural selection|natural selection]]}}
{{defn| }}

{{term|niche adaptation}}
{{defn| }}

{{term|niche preference}}
{{defn| }}

{{term|noncompetitive gametic isolation}}
{{defn| }}

{{term|nongenetic barrier}}
{{defn| }}

{{term|non-geographic speciation}}
{{defn| }}

==O==

==P==
{{term|[[Biology:Paleopolyploidy|paleopolyploidy]]}}
{{defn| }}

{{term|para-allopatric speciation}}
{{defn|A mode of speciation where divergence begins in parapatry, but is completed in allopatry.<ref name="Coyne&Orr2004"/>}}

{{term|parallel speciation}}
{{defn| }}

[[File:Parapatric Speciation Schematic.svg|Right|thumb|upright=1.3|A diagram representing population subject to a selective gradient of phenotypic or genotypic frequencies (a cline). Each end of the gradient experiences different selective conditions (divergent selection). Reproductive isolation occurs upon the formation of a hybrid zone. In most cases, the hybrid zone may become eliminated due to a selective disadvantage. This effectively completes the speciation process.]]
{{term|[[Biology:Parapatric speciation|parapatric speciation]]}}
{{defn| }}

{{term|[[Biology:Paraphyly|paraphyly]]}}
{{defn| }}

{{term|[[Biology:Parthenogenesis|parthenogenesis]]}}
{{defn| }}

{{term|peak shift model}}
{{defn| }}

[[File:Peripatric Speciation Schematic.svg|right|thumb|upright=1.3|In peripatric speciation, a small population becomes isolated on the periphery of the central population evolving reproductive isolation (blue) due to reduced gene flow.]]
{{term|[[Biology:Peripatric speciation|peripatric speciation]]}}
{{defn|A variation of allopatric speciation where a new species forms from a small, peripheral isolated population.<ref>{{Citation |title=Theory and speciation | author=Michael Turelli, Nicholas H. Barton, and Jerry A. Coyne | journal=Trends in Ecology & Evolution | year=2001 | volume=16 | issue=7 | pages=330–343 | doi=10.1016/s0169-5347(01)02177-2}}</ref> It is sometimes referred to as centripetal speciation in contrast to centrifugal speciation.}}

{{term|[[Biology:Phylogenetics|phylogenetics]]}}
{{defn|the study of the [[Biology:Evolution|evolution]]ary history and relationships among individuals or groups of organisms (e.g. [[Biology:Species|species]], or [[Social:Population|population]]s).}}

{{term|phylogenetic species concept}}
{{defn| }}

{{term|[[Biology:Phylogeography|phylogeography]]}}
{{defn| }}

{{term|[[Biology:Phylogenetic tree|phylogeny]]}}
{{defn| }}

{{term|pollinator isolation}}
{{defn| }}

{{term|[[Biology:Polymorphism|polymorphism]]}}
{{defn| }}

{{term|[[Biology:Polyploidy|polyploidy]]}}
{{defn| }}

{{term|[[Biology:Population bottleneck|population bottleneck]]}}
{{defn|A sharp reduction in the size of a species [[Social:Population|population]].}}

{{term|postmating barrier}}
{{defn| }}

{{term|postmating prezygotic isolation}}
{{defn| }}

{{term|postzygotic isolation}}
{{defn| }}

{{term|premating barrier}}
{{defn| }}

{{term|premating isolation}}
{{defn| }}

{{term|prezygotic isolation}}
{{defn| }}

{{term|punctuated equilibrium}}
{{defn| }}

==Q==
{{term|[[Biology:Peripatric speciation#Quantum and budding speciation|quantum speciation]]}}
{{defn|A chromosomal model of speciation that occurs rapidly when a cross-fertilizing plant species buds off from a larger population on the periphery, experiencing interbreeding and strong genetic drift that results a new species.<ref name="Grant1971">{{Citation|title=Plant Speciation |author=Verne Grant |date=1971 |publisher=Columbia University Press |location=New York |isbn=978-0231083263 |pages=432 }}</ref><ref>{{Citation|title=Speciational trends and the role of species in macroevolution |author=Douglas J. Futuyma |journal=The American Naturalist |year=1989 |volume=134 |issue=2 |pages=318–321 |doi=10.1086/284983 }}</ref><ref>{{Citation|title=Chromosomal rearrangements and speciation |author=Loren H. Rieseberg |journal=Trends in Ecology & Evolution |year=2001 |volume=16 |issue=7 |pages=351–358 |doi= 10.1016/s0169-5347(01)02187-5}}</ref> The model is similar to that of Ernst Mayr's [[Biology:Peripatric speciation|peripatric speciation]].<ref name="Gottlieb2003">{{Citation|title=Rethinking classic examples of recent speciation in plants |author=L. D. Gottlieb |journal=New Phytologist |year=2003 |volume=161 |issue= |pages=71–82 |doi=10.1046/j.1469-8137.2003.00922.x }}</ref>}}

==R==
{{term|recognition species concept}}
{{defn| }}

{{term|recombinational speciation}}
{{defn| }}

{{term|refugia}}
{{defn| }}

[[File:Speciation by Reinforcement Schematic.svg|right|thumb|upright=1.3|Reinforcement assists speciation by [[Biology:Natural selection|selecting]] against hybrids.]]
{{term|[[Biology:Reinforcement (speciation)|reinforcement]]}}
{{defn|A process of speciation where [[Biology:Natural selection|natural selection]] increases the [[Biology:Reproductive isolation|reproductive isolation]] between two populations of species as a result of selection acting against the production of [[Biology:Hybrid|hybrid]] individuals of low [[Biology:Fitness|fitness]].<ref name="Coyne&Orr2004"/> See also ''Evidence of speciation by reinforcement''}}

[[File:Reproductive Character Displacement.png|right|thumb|upright=1.3|Reproductive character displacement sometimes occurs when two allopatric populations come into secondary contact. Once in sympatry, changes can be seen in mating-associated traits only in the zone of contact. This is a common pattern found in speciation by reinforcement.]]
{{term|reproductive character displacement}}
{{defn| }}

{{term|reproductive isolating barriers}}
{{defn|The set of mechanisms responsible for speciation}}

{{term|[[Biology:Reproductive isolation|reproductive isolation]]}}
{{defn|When two species mate and cannot produce fertile offspring. Isolating mechanisms are typically classified as prezygotic (isolating barriers occurring before the formation of a zygote) and postzygotic (isolating barriers occurring after the formation of a zygote).}}

[[File:Ring Species (gene flow around a barrier).png|Right|thumb|upright=1.3|In a ring species, individuals are able to successfully reproduce (exchange genes) with members of their own species in adjacent populations occupying a suitable [[Earth:Habitat|habitat]] around a geographic barrier. Individuals at the ends of the cline are unable to reproduce when they come into contact.]]
{{term|[[Biology:Ring species|ring species]]}}
{{defn|Connected populations of a species, each of which can interbreed with closely sited related populations, but for which there exist at least two "end" populations in the series, which are too distantly related to interbreed.}}

==S== 
[[File:Consequences of secondary contact Schematic.svg|right|thumb|upright=1.3|The four outcomes of secondary contact:<br>
1. An ''extrinsic'' barrier separates a species population into two but they come into contact before reproductive isolation is sufficient to result in speciation. The two populations fuse back into one species<br>
2. Speciation by reinforcement<br>
3. Two separated populations stay genetically distinct while [[Biology:Hybrid swarm|hybrid swarm]]s form in the zone of contact<br>
4. [[Biology:Genetic recombination|Genome recombination]] results in speciation of the two populations, with an additional [[Biology:Hybrid|hybrid species]]. All three species are separated by ''intrinsic'' reproductive barriers<ref name="eLS2012Hvala">{{cite book | last= Hvala | first= John A. | last2 =Wood | first2 =Troy E. |title =Speciation: Introduction | journal =eLS | date =2012 | doi =10.1002/9780470015902.a0001709.pub3| isbn= 978-0470016176 }}</ref>]]
{{term|[[Biology:Secondary contact|secondary contact]]}}
{{defn| }}

{{term|semi-geographic speciation}}
{{defn| }}

{{term|semipermeable species boundary}}
{{defn|The idea that gene flow can occur between two species but that certain alleles at particular [[Biology:Locus (genetics)|loci]] can exchange whereas others cannot.<ref name="Harrison2012"/> It is often used to describe hybrid zones and has also been referred to as '''porous'''.<ref name="Harrison2012"/>}}

{{term|[[Biology:Sexual selection|sexual selection]]}}
{{defn| }}

{{term|[[Biology:Speciation|speciation]]}}
{{defn|The [[Biology:Evolution|evolution]]ary process by which populations evolve to become distinct [[Biology:Species|species]].}}

{{term|[[Organization:Laboratory experiments of speciation|speciation experiment]]}}
{{defn|An experiment that attempts to replicate reproductive isolation in nature in a [[Scientific control|scientifically controlled]], laboratory setting.}}

{{term|speciation in the fossil record}}
{{defn|Speciation that can be detected as occurring in [[Biology:Fossil|fossil]]ized organisms.}}

{{term|speciation rate}}
{{defn| }}

{{term|[[Biology:Species|species]]}}
{{defn|The basic unit of biological classification, a [[Biology:Taxonomic rank|taxonomic rank]], and a unit of [[Biology:Biodiversity|biodiversity]] that has no universally agreed upon, satisfactory definition.}}

{{term|[[Biology:Species complex|species complex]]}}
{{defn| }}

{{term|[[Biology:Species concept|species concept]]}}
{{defn| }}

{{term|[[Biology:Species problem|species problem]]}}
{{defn|The difficulty in defining what a species is and determining identification of organisms across all of life.<ref>{{Citation|title=Fuzzy species revisited |author=William P. Hanage |journal=BMC Biology |year=2013 |volume=11 |issue=41 |pages=41 |doi=10.1186/1741-7007-11-41 |pmid=23587266 |pmc=3626887 }}</ref>}}

{{term|stasipatric speciation}}
{{defn| }}

{{term|stasis}}
{{defn|A species linage that experiences little [[Biology:Phenotype|phenotypic]] or [[Biology:Genotype|genotypic]] change over time.<ref name="Vauxetal2016"/>}}

{{term|stepping-stone speciation}}
{{defn| }}

{{term|sterility}}
{{defn| }}

{{term|suture zone}}
{{defn| }}

{{term|swamping effect}}
{{defn| }}

{{term|[[Biology:Sympatric speciation|sympatric speciation]]}}
{{defn| }}

{{term|[[Earth:Sympatry|sympatry]]}}
{{defn| }}

==T==
{{term|temporal isolation}}
{{defn| }}

{{term|tension zone}}
{{defn|}}

{{term|[[Biology:Type|type]]}}
{{defn|}}

{{term|[[Biology:Type species|type species]]}}
{{defn|}}

==U==

==V==
{{term|vicariance biogeography}}
{{defn|A biogeographic approach to species distributions that uses their phylogenetic histories—patterns resulting from allopatric speciation events in the past.<ref>{{Citation |title=Biography |edition=2 |author=M. V. Lomolino & J. H. Brown |date=1998 |pages=[https://archive.org/details/biogeography0000brow/page/352 352–357] |publisher=Sinauer Associates, Sunderland, MA. |isbn=978-0-87893-073-9 |url=https://archive.org/details/biogeography0000brow/page/352 }}</ref>}}

{{term|vicariant speciation}}
{{defn|A biogeographic term meaning the geographic isolation of two species populations (as in [[Biology:Allopatric speciation|allopatric speciation]]).}}

==W==
{{term|[[Biology:Wahlund effect|Wahlund effect]]}}
{{defn| }}

{{term|Wallace effect}}
{{defn| }}

==X==

==Y==

==Z==

{{glossary end}}

==References==
{{reflist|30em}}

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{{Glossaries of science and engineering}}

{{DEFAULTSORT:Speciation}}
[[Category:Evolutionary biology]]

{{Sourceattribution|Glossary of speciation|1}}