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Relict
A relict is a surviving remnant of a natural phenomenon. Biology A relict (or relic) is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas. Geology and geomorphology In geology, a relict is a structure or mineral from a parent rock that did not undergo metamorphosis when the surrounding rock did, or a rock that survived a destructive geologic process. In geomorphology, a relict landform is a landform formed by either erosive or constructive surficial processes that are no longer active as they were in the past. A glacial relict is a cold-adapted organism that is a remnant of a larger distribution that existed in the ice ages. Human populations As revealed by DNA testing, a relict population is an ancient people in an area, who have been largely supplanted by a later group of migrants and their descendants. In various places around the world, minority ethnic groups represent lineages of ancient human migrations i ...
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Catocala Relicta
''Catocala relicta'', the white underwing or relict, is a moth of the family Erebidae. The species was first described by Francis Walker in 1858. It lives in southern Canada, from Newfoundland to Vancouver Island, south to Missouri, and Arizona. The wingspan is 67–75 mm. Adults are on wing from July to September in one generation depending on the location. The larvae feed on ''Betula papyrifera'', '' Carya ovata'', ''Populus alba'', ''Populus balsamifera'', ''Populus deltoides'', ''Populus nigra'', ''Populus tremuloides'', ''Quercus'' species, and ''Salix Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...'' species (including '' Salix eriocephala''). Subspecies ''Catocala relicta elda'', recorded from Oregon, was formerly considered a subspecies, but is now thought t ...
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Endemism
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies t ...
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Glacial Relict
A glacial relict is a population of a cold-adapted species that has been left behind as the range of the species changed after an ice age ended. Glacial relicts are usually found in enclaves "under relatively benign conditions". Examples: *The biogeography of various aquatic species deemed glacial relicts that are found in Lake Sommen is likely related to a different geography during the early history of the lake. One theory claims that aquatic species were transferred from the Baltic Ice Lake through a natural lock system in connection with a temporary advance of the ice-front during the Younger Dryas. On land, the unusual occurrence of dwarf birch near Sund is also judged to be a leftover from a cold geological past. See also *Biodiversity hotspot * Last Glacial Maximum refugia * Nunatak hypothesis *Rapoport's rule Rapoport's rule is an ecogeographical rule that states that latitudinal ranges of plants and animals are generally smaller at lower latitudes than at higher l ...
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Living Fossil
A living fossil is an extant taxon that cosmetically resembles related species known only from the fossil record. To be considered a living fossil, the fossil species must be old relative to the time of origin of the extant clade. Living fossils commonly are of species-poor lineages, but they need not be. While the body plan of a living fossil remains superficially similar, it is never the same species as the remote relatives it resembles, because genetic drift would inevitably change its chromosomal structure. Living fossils exhibit stasis (also called "bradytely") over geologically long time scales. Popular literature may wrongly claim that a "living fossil" has undergone no significant evolution since fossil times, with practically no molecular evolution or morphological changes. Scientific investigations have repeatedly discredited such claims. The minimal superficial changes to living fossils are mistakenly declared as an absence of evolution, but they are examples of ...
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Widow
A widow (female) or widower (male) is a person whose spouse has died. Terminology The state of having lost one's spouse to death is termed ''widowhood''. An archaic term for a widow is "relict," literally "someone left over". This word can sometimes be found on older gravestones. The word "widow" comes from an Indo-European root meaning "widow" and has cognates across Indo-European languages. The male form, "widower", is first attested in the 14th century, by the 19th century supplanting "widow" with reference to men. The term ''widowhood'' can be used for either sex, at least according to some dictionaries, but the word ''widowerhood'' is also listed in some dictionaries. Occasionally, the word ''viduity'' is used. The adjective for either sex is ''widowed''. These terms are not applied to a divorcé(e) following the death of an ex-spouse. Effects on health The phenomenon that refers to the increased mortality rate after the death of a spouse is called the '' widowhood ...
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Refugium (population Biology)
Refugium, plural refugia, the Latin for "refuge" or "hideaway", may refer to: * Refugium (fishkeeping), an appendage to a marine, brackish, or freshwater fish tank that shares the same water supply * Refugium (population biology), a location of an isolated or relict population of a once widespread animal or plant species ** Last Glacial Maximum refugia specifically, in anthropology * Refugium Range The Refugium Range is a low, small mountain range comprising the mountains/hills of the Brooks Peninsula on northern Vancouver Island, British Columbia, Canada. It has an area of and is a subrange of the Vancouver Island Ranges which in turn for ..., a mountain range on Vancouver Island, British Columbia, Canada See also * Refuge (Buddhism) * Refugium Peccatorum {{disambiguation ...
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Relic
In religion, a relic is an object or article of religious significance from the past. It usually consists of the physical remains of a saint or the personal effects of the saint or venerated person preserved for purposes of veneration as a tangible memorial. Relics are an important aspect of some forms of Buddhism, Christianity, Islam, shamanism, and many other religions. ''Relic'' derives from the Latin ''reliquiae'', meaning "remains", and a form of the Latin verb ''relinquere'', to "leave behind, or abandon". A reliquary is a shrine that houses one or more religious relics. In classical antiquity In ancient Greece, a city or sanctuary might claim to possess, without necessarily displaying, the remains of a venerated hero as a part of a hero cult. Other venerable objects associated with the hero were more likely to be on display in sanctuaries, such as spears, shields, or other weaponry; chariots, ships or figureheads; furniture such as chairs or tripods; and clothing. The ...
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Geology Terminology
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of Ear ...
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Biogeography
Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time. Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, isolation and habitat area.Brown University, "Biogeography." Accessed February 24, 2014. . Phytogeography is the branch of biogeography that studies the distribution of plants. Zoogeography is the branch that studies distribution of animals. Mycogeography is the branch that studies distribution of fungi, such as mushrooms. Knowledge of spatial variation in the numbers and types of organisms is as vital to us today as it was to our early human ancestors, as we adapt to heterogeneous but geographically predictable environments. Biogeography is an integrative field of inquiry that unites concepts and information from ecology, evolutionary biology, taxonomy, geology, physical geography, palaeontology, and climatology.Dansereau, Pierre. ...
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Palaeochannel
A palaeochannel, also spelt paleochannel and also known as palaeovalley or palaeoriver, is a geological term describing a remnant of an inactive river or stream channel that has been filled or buried by younger sediment. The sediments that the ancient channel is cut into or buried by can be unconsolidated, semi-consolidated, consolidated or lithified. The word ''palaeochannel'' is formed from the ''palaeo'', meaning "old," and ''channel''. Recognition A palaeochannel is distinct from the overbank deposits of currently-active river channels, including ephemeral water courses that do not regularly flow (such as the Todd River, Central Australia) because the river bed is filled with sedimentary deposits unrelated to the normal bed load of the current drainage pattern. Many palaeochannels are arranged on old drainage patterns, distinct from the current drainage system of a catchment. For example, palaeochannels may relate to a system of rivers and creeks that drained east–west ...
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Hysteresis
Hysteresis is the dependence of the state of a system on its history. For example, a magnet may have more than one possible magnetic moment in a given magnetic field, depending on how the field changed in the past. Plots of a single component of the moment often form a loop or hysteresis curve, where there are different values of one variable depending on the direction of change of another variable. This history dependence is the basis of memory in a hard disk drive and the remanence that retains a record of the Earth's magnetic field magnitude in the past. Hysteresis occurs in ferromagnetic and ferroelectric materials, as well as in the deformation of rubber bands and shape-memory alloys and many other natural phenomena. In natural systems it is often associated with irreversible thermodynamic change such as phase transitions and with internal friction; and dissipation is a common side effect. Hysteresis can be found in physics, chemistry, engineering, biology, and econ ...
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Historical Linguistics
Historical linguistics, also termed diachronic linguistics, is the scientific study of language change over time. Principal concerns of historical linguistics include: # to describe and account for observed changes in particular languages # to reconstruct the pre-history of languages and to determine their relatedness, grouping them into language families ( comparative linguistics) # to develop general theories about how and why language changes # to describe the history of speech communities # to study the history of words, i.e. etymology Historical linguistics is founded on the Uniformitarian Principle, which is defined by linguist Donald Ringe as: History and development Western modern historical linguistics dates from the late-18th century. It grew out of the earlier discipline of philology, the study of ancient texts and documents dating back to antiquity. At first, historical linguistics served as the cornerstone of comparative linguistics, primarily as a t ...
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