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Hybrid Zone
A hybrid zone exists where the ranges of two interbreeding species or diverged intraspecific lineages meet and cross-fertilize. Hybrid zones can form ''in situ'' due to the evolution of a new lineage but generally they result from secondary contact of the parental forms after a period of geographic isolation, which allowed their differentiation (or speciation). Hybrid zones are useful in studying the genetics of speciation as they can provide natural examples of differentiation and (sometimes) gene flow between populations that are at some point between representing a single species and representing multiple species in reproductive isolation. Definition Hybrid zones are areas where the hybrid offspring of two divergent taxa (species, subspecies or genetic "forms") are prevalent and there is a cline in the genetic composition of populations from one taxon to the other. The two (or more) genetically differentiated species or lineages contributing to formation of a hybrid zone are r ...
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Hybrid Figure Resulting From Secondary Contact
Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two different genetic parent strains * Hybrid (particle physics), a valence quark-antiquark pair and one or more gluons * Hybrid solar eclipse, a rare solar eclipse type Technology Transportation * Hybrid vehicle, a vehicle using more than one power source or an engine sourced from a different chassis ** Hybrid electric vehicle, a vehicle using both internal combustion and electric power sources *** Plug-in hybrid, whose battery can be recharged by a charging cable * Hybrid bicycle, a bicycle with features of road and mountain bikes * Hybrid train, a locomotive, railcar, or train that uses an onboard rechargeable energy storage system * Hybrid motorcycle, a motorcycle built using components from more than one original-manufacturer products, ...
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Allopatric Speciation
Allopatric speciation () – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from each other to an extent that prevents or interferes with gene flow. Various geographic changes can arise such as the movement of continents, and the formation of mountains, islands, bodies of water, or glaciers. Human activity such as agriculture or developments can also change the distribution of species populations. These factors can substantially alter a region's geography, resulting in the separation of a species population into isolated subpopulations. The vicariant populations then undergo genetic changes as they become subjected to different selective pressures, experience genetic drift, and accumulate different mutations in the separated populations' gene pools. The barriers prevent the exchange of genetic information betwe ...
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Reinforcement (speciation)
Reinforcement is a process of speciation where natural selection increases the reproductive isolation (further divided to pre-zygotic isolation and post-zygotic isolation) between two populations of species. This occurs as a result of selection acting against the production of hybrid individuals of low fitness. The idea was originally developed by Alfred Russel Wallace and is sometimes referred to as the Wallace effect. The modern concept of reinforcement originates from Theodosius Dobzhansky. He envisioned a species separated allopatrically, where during secondary contact the two populations mate, producing hybrids with lower fitness. Natural selection results from the hybrid's inability to produce viable offspring; thus members of one species who do not mate with members of the other have greater reproductive success. This favors the evolution of greater prezygotic isolation (differences in behavior or biology that inhibit formation of hybrid zygotes). Reinforcement is on ...
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Genetics (journal)
''Genetics'' is a monthly scientific journal publishing investigations bearing on heredity, genetics, biochemistry and molecular biology. Genetics is published by the Genetics Society of America. It has a delayed open access policy, and makes articles available online without a subscription after 12 months have elapsed since first publication. Since 2010, it is published online-only.http://www.councilscienceeditors.org/wp-content/uploads/v36n1p14-15_17.pdf George Harrison Shull George Harrison Shull (April 15, 1874 – September 28, 1954) was an eminent American plant geneticist and the younger brother of botanical illustrator and plant breeder J. Marion Shull. He was born on a farm in Clark County, Ohio, graduated fr ... was the founding editor of ''Genetics'' in 1916. Editors-in-Chief References External linksOfficial website Genetics journals Delayed open access journals English-language journals Publications established in 1916 Online-only journals {{ge ...
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Quarterly Review Of Biology
''The Quarterly Review of Biology'' is a peer-reviewed scientific journal covering all aspects of biology. It was established in 1926 by Raymond Pearl. In the 1960s it was purchased by the Stony Brook Foundation when the editor H. Bentley Glass became academic vice president of Stony Brook University. The editor-in-chief is Daniel E. Dykhuizen (Stony Brook University). It is currently published by the University of Chicago Press. Aims and scope The journal publishes review articles. Beyond the core biological sciences, the journal also covers related areas, including policy studies and the history and philosophy of science. There is also a book review section. Abstracting and indexing The journal is abstracted and indexed in Biological Abstracts, BIOSIS Previews, and the Science Citation Index The Science Citation Index Expanded – previously entitled Science Citation Index – is a citation index originally produced by the Institute for Scientific Information (ISI) and cr ...
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Heredity (journal)
''Heredity'' is a monthly peer reviewed scientific journal published by Nature Portfolio. It covers heredity in a biological sense, i.e. genetics. The journal was founded by Ronald Fisher and C. D. Darlington in 1947 and is the official journal of The Genetics Society. From 1996 the publishing was taken over by Nature Portfolio. The editor-in-chief is Sara Goodacre. According to the ''Journal Citation Reports'', the journal has a 2021 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as ... of 3.832, ranking it 61st out of 173 journals in the category "Ecology", 19th out of 51 journals in the category "Evolutionary Biology", and 79th out of 175 journals in the category "Genetics & Heredity". References External links * The Genetics Society* Genetics in the U ...
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Infertility
Infertility is the inability of a person, animal or plant to reproduce by natural means. It is usually not the natural state of a healthy adult, except notably among certain eusocial species (mostly haplodiploid insects). It is the normal state of a human child or other young offspring, because they have not undergone puberty, which is the body's start of reproductive capacity. In humans, infertility is the inability to become pregnant after one year of unprotected and regular sexual intercourse involving a male and female partner.Chowdhury SH, Cozma AI, Chowdhury JH. Infertility. Essentials for the Canadian Medical Licensing Exam: Review and Prep for MCCQE Part I. 2nd edition. Wolters Kluwer. Hong Kong. 2017. There are many causes of infertility, including some that medical intervention can treat. Estimates from 1997 suggest that worldwide about five percent of all heterosexual couples have an unresolved problem with infertility. Many more couples, however, experience inv ...
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Gene Complexes
A supergene is a chromosomal region encompassing multiple neighboring genes that are inherited together because of close genetic linkage, i.e. much less recombination than would normally be expected. This mode of inheritance can be due to genomic rearrangements between supergene variants. A supergene region can contain few, functionally related genes that clearly contribute to a shared phenotype. Phenotypes encoded by supergenes Supergenes have cis-effects due to multiple loci (which may be within a gene, or within a single gene's regulatory region), and tight linkage. They are classically polymorphic, whereby different supergene variants code for different phenotypes. Classic supergenes include many sex chromosomes, the ''Primula'' heterostyly locus, which controls "pin" and " thrum" types, and the locus controlling Batesian mimetic polymorphism in ''Papilio memnon'' butterflies. Recently discovered supergenes are responsible complex phenotypes including color-morphs ...
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Australian Journal Of Zoology
The ''Australian Journal of Zoology'' is a bimonthly peer-reviewed scientific journal published by CSIRO Publishing. It covers research on all aspects of zoology, with a special focus on the fauna of Australia. The editor-in-chief is Paul Cooper (Australian National University). Abstracting and indexing The journal is abstracted and indexed in AGRICOLA, Elsevier Biobase, Biological Abstracts, BIOSIS Previews, CAB Abstracts, Chemical Abstracts Service, Current Contents/Agriculture, Biology & Environmental Sciences, Science Citation Index Expanded, Scopus, and The Zoological Record. According to the ''Journal Citation Reports'', the journal has a 2021 impact factor of 1.073. See also *List of zoology journals This is a list of scientific journals which cover the field of zoology. A * '' Acta Entomologica Musei Nationalis Pragae'' * '' Acta Zoologica Academiae Scientiarum Hungaricae'' * '' Acta Zoologica Bulgarica'' * ''Acta Zoologica Mexicana'' * '' ... References External ...
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Character Displacement
Character displacement is the phenomenon where differences among similar species whose distributions overlap geographically are accentuated in regions where the species co-occur, but are minimized or lost where the species' distributions do not overlap. This pattern results from evolutionary change driven by biological competition among species for a limited resource (e.g. food). The rationale for character displacement stems from the competitive exclusion principle, also called Gause's Law, which contends that to coexist in a stable environment two competing species must differ in their respective ecological niche; without differentiation, one species will eliminate or exclude the other through competition. Character displacement was first explicitly explained by William L. Brown Jr. and E. O. Wilson in 1956: "Two closely related species have overlapping ranges. In the parts of the ranges where one species occurs alone, the populations of that species are similar to the other ...
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Natural Selection
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. Charles Darwin popularised the term "natural selection", contrasting it with artificial selection, which in his view is intentional, whereas natural selection is not. Variation exists within all populations of organisms. This occurs partly because random mutations arise in the genome of an individual organism, and their offspring can inherit such mutations. Throughout the lives of the individuals, their genomes interact with their environments to cause variations in traits. The environment of a genome includes the molecular biology in the cell, other cells, other individuals, populations, species, as well as the abiotic environment. Because individuals with certain variants of the trait tend to survive and reproduce more than individuals ...
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Genetic Hitchhiking
Genetic may refer to: *Genetics, in biology, the science of genes, heredity, and the variation of organisms **Genetic, used as an adjective, refers to genes ***Genetic disorder, any disorder caused by a genetic mutation, whether inherited or de novo ***Genetic mutation In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA replication, DNA or viral repl ..., a change in a gene **** Heredity, genes and their mutations being passed from parents to offspring ** Genetic recombination, refers to the recombining of alleles resulting in a new molecule of DNA * Genetic relationship (linguistics), in linguistics, a relationship between two languages with a common ancestor language * Genetic algorithm, in computer science, a kind of search technique modeled on evolutionary biology See also * Genetic memory (other) {{d ...
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