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Introgressed
Introgression, also known as introgressive hybridization, in genetics is the transfer of genetic material from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species. Introgression is a long-term process, even when artificial; it may take many hybrid generations before significant backcrossing occurs. This process is distinct from most forms of gene flow in that it occurs between two populations of different species, rather than two populations of the same species. Introgression also differs from simple hybridization. Simple hybridization results in a relatively even mixture; gene and allele frequencies in the first generation will be a uniform mix of two parental species, such as that observed in mules. Introgression, on the other hand, results in a complex, highly variable mixture of genes, and may only involve a minimal percentage of the donor genome. Definition Introgression or introgressive hybr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denisovan
The Denisovans or Denisova hominins ) are an extinct species or subspecies of archaic human that ranged across Asia during the Lower and Middle Paleolithic. Denisovans are known from few physical remains and consequently, most of what is known about them comes from DNA evidence. No formal species name has been established pending more complete fossil material. The first identification of a Denisovan individual occurred in 2010, based on mitochondrial DNA (mtDNA) extracted from a juvenile female finger bone excavated from the Siberian Denisova Cave in the Altai Mountains in 2008. Nuclear DNA indicates close affinities with Neanderthals. The cave was also periodically inhabited by Neanderthals, but it is unclear whether Neanderthals and Denisovans ever cohabited in the cave. Additional specimens from Denisova Cave were subsequently identified, as was a single specimen from the Baishiya Karst Cave on the Tibetan Plateau. DNA evidence suggests they had dark skin, eyes, and hair, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcephalin
Microcephalin (MCPH1) is a gene that is expressed during fetal brain development. Certain mutations in ''MCPH1'', when homozygous, cause primary microcephaly—a severely diminished brain. Hence, it has been assumed that variants have a role in brain development. However, in normal individuals no effect on mental ability or behavior has yet been demonstrated in either this or another similarly studied microcephaly gene, '' ASPM''. However, an association has been established between normal variation in brain structure, as measured with MRI (i.e., primarily '' cortical surface area'' and total brain volume) but only in females, and common genetic variants within both the MCPH1 gene and another similarly studied microcephaly gene, '' CDK5RAP2''. Structure Microcephalin proteins contain the following three domains: * N-terminal BRCT domain * Central microcephalin protein domain () * C-terminal BRCT domain Expression in the brain MCPH1 is expressed in the fetal brain, in the devel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neanderthal
Neanderthals (, also ''Homo neanderthalensis'' and erroneously ''Homo sapiens neanderthalensis''), also written as Neandertals, are an extinct species or subspecies of archaic humans who lived in Eurasia until about 40,000 years ago. While the "causes of Neanderthal disappearance about 40,000 years ago remain highly contested," demographic factors such as small population size, inbreeding and genetic drift, are considered probable factors. Other scholars have proposed competitive replacement, assimilation into the modern human genome (bred into extinction), great climatic change, disease, or a combination of these factors. It is unclear when the line of Neanderthals split from that of modern humans; studies have produced various intervals ranging from 315,000 to more than 800,000 years ago. The date of divergence of Neanderthals from their ancestor ''H. heidelbergensis'' is also unclear. The oldest potential Neanderthal bones date to 430,000 years ago, but the classification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid PNGT
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, such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Biology And Evolution
''Molecular Biology and Evolution'' is a monthly peer-reviewed scientific journal published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. It publishes work in the intersection of molecular biology and evolutionary biology. The founding editors-in-chief were Walter Fitch and Masatoshi Nei; the present editor-in-chief is Sudhir Kumar. According to the ''Journal Citation Reports'', the journal has a 2017 Impact Factor of 10.217, a 2018 Impact Factor of 14.797, a 2019 Impact Factor of 11.062, and 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 i ... of 8.800 References External links * Molecular and cellular biology journals Evolutionary biology journals English-language journals Monthly journals Oxford Universit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are the histones. These proteins, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation. Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated ( S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now called si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agriculture
Agriculture or farming is the practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to live in cities. The history of agriculture began thousands of years ago. After gathering wild grains beginning at least 105,000 years ago, nascent farmers began to plant them around 11,500 years ago. Sheep, goats, pigs and cattle were domesticated over 10,000 years ago. Plants were independently cultivated in at least 11 regions of the world. Industrial agriculture based on large-scale monoculture in the twentieth century came to dominate agricultural output, though about 2 billion people still depended on subsistence agriculture. The major agricultural products can be broadly grouped into foods, fibers, fuels, and raw materials (such as rubber). Food classes include cereals (grains), vegetables, fruits, cooking oils, meat, milk, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Troglomorphism
Troglomorphism is the morphological adaptation of an animal to living in the constant darkness of caves, characterised by features such as loss of pigment, reduced eyesight or blindness, and frequently with attenuated bodies and/or appendages. The terms troglobitic, stygobitic, stygofauna, troglofauna, and hypogean or hypogeic, are often used for cave-dwelling organisms. A 2012 study by a team from the National University of Singapore found that reductive changes in freshwater cave crabs evolved at the same rate as constructive changes. This shows that both selection and evolution have a role in advancing reductive changes (e.g smaller eyes) and constructive changes (e.g larger claws), making troglomorphic adaptations subject to strong factors that affect an organism's morphology. Troglomorphism occurs in molluscs, velvet worms, arachnids, myriapods, crustaceans, insects, fish, amphibians (notably cave salamanders) and reptiles. To date no mammals or birds have been found to live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astroblepus
''Astroblepus'' is a genus of fish in the family Astroblepidae found in South America and Panama. This genus is the only member of its family. These catfishes are primarily found in torrential streams in the Andean area. ''Astroblepus pholeter'' and ''A. riberae'' are troglobites adapted to living in subterranean water systems. These species are typically small, less than . The largest species reaches . These fish have suckermouths like those of loricariids. They have two pairs of barbels, maxillary and nasal. The dorsal fin spine lacks a locking mechanism. These fish also have odontodes, tiny teeth on their skin. All species exhibit a conical, pointy type on their fin rays like that found in other loricarioids; other species also exhibit a blunt type that is only found on their skin. Some of these fish are able to live in high altitude and climb the faces of waterfalls. Their climbing ability comes from specially developed pelvic fins, as well as their suckermouths. In their Ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louisiana
Louisiana , group=pronunciation (French: ''La Louisiane'') is a state in the Deep South and South Central regions of the United States. It is the 20th-smallest by area and the 25th most populous of the 50 U.S. states. Louisiana is bordered by the state of Texas to the west, Arkansas to the north, Mississippi to the east, and the Gulf of Mexico to the south. A large part of its eastern boundary is demarcated by the Mississippi River. Louisiana is the only U.S. state with political subdivisions termed parishes, which are equivalent to counties, making it one of only two U.S. states not subdivided into counties (the other being Alaska and its boroughs). The state's capital is Baton Rouge, and its largest city is New Orleans, with a population of roughly 383,000 people. Some Louisiana urban environments have a multicultural, multilingual heritage, being so strongly influenced by a mixture of 18th century Louisiana French, Dominican Creole, Spanish, French Canadian, Acadi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iris (plant)
''Iris'' is a flowering plant genus of 310 accepted species with showy flowers. As well as being the scientific name, ''iris'' is also widely used as a common name for all ''Iris'' species, as well as some belonging to other closely related genera. A common name for some species is 'flags', while the plants of the subgenus '' Scorpiris'' are widely known as 'junos', particularly in horticulture. It is a popular garden flower. The often-segregated, monotypic genera '' Belamcanda'' (blackberry lily, ''I. domestica''), '' Hermodactylus'' (snake's head iris, ''I. tuberosa''), and ''Pardanthopsis'' (vesper iris, '' I. dichotoma'') are currently included in ''Iris''. Three Iris varieties are used in the Iris flower data set outlined by Ronald Fisher in his 1936 paper ''The use of multiple measurements in taxonomic problems'' as an example of linear discriminant analysis. Description Irises are perennial plants, growing from creeping rhizomes (rhizomatous irises) or, in drier cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canid Hybrid
Canid hybrids are the result of interbreeding between the species of the genus ''Canis''. This often occurs in the wild, and in particular between domestic or feral dogs with wild native canids. Genetic considerations The wolf-like canids are a group of large carnivores that are genetically closely related because they all possess 78 chromosomes, arranged in 39 pairs and are karyologically indistinguishable from each other. The group includes the genera ''Canis'', ''Cuon'', ''Lupulella'' and ''Lycaon''. The members are the domestic dog ''(C. familiaris)'', gray wolf (''C. lupus''), dingo (''C. lupus dingo''), coyote (''C. latrans''), golden jackal (''C. aureus''), African wolf (''C. lupaster''), Ethiopian wolf (''C. simensis''), dhole (''Cuon alpinus''), black-backed jackal (''Lupulella mesomelas''), side-striped jackal (''L. adusta'') and African wild dog (''Lycaon pictus''). Newly proposed members include the red wolf (''Canis rufus''), and the eastern wolf (''Canis lycaon''), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
