Difference between revisions of "Extinction"

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#REDIRECT [[Death]]
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[[File:lighterstill.jpg]][[File:Extinction.jpg|right|frame]]
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==Etymology==
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[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English], from [[Latin]] exstinctus, past participle of exstinguere
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*Date: [https://www.wikipedia.org/wiki/15th_Century 15th century]
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==Definitions==
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*1 a : no longer burning
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:b : no longer [[active]] <an extinct volcano>
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*2 : no longer existing <an extinct [[animal]]>
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*3 a : gone out of use : superseded
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:b : having no qualified claimant <an extinct title>
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==Description==
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In [[biology]] and [[ecology]], '''extinction''' is the end of an [[organism ]] or [[group]] of [https://en.wikipedia.org/wiki/Taxon taxa]. The [[moment]] of extinction is generally [[considered]] to be the [[death]] of the last [[individual]] of that [[species]] (although the capacity to [[Reproduction|breed]] and recover may have been lost before this point). Because a [[species]]' [[potential]] range may be very large, determining this [[moment]] is [[difficult]], and is usually done retrospectively. This difficulty leads to [[phenomena]] such as [https://en.wikipedia.org/wiki/Lazarus_taxon Lazarus taxa], where a [[species]] presumed extinct abruptly "re-appears" (typically in the [https://en.wikipedia.org/wiki/Fossil fossil record]) after a period of [[apparent]] [[absence]].
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Through [[evolution]], new [[species]] arise through the [[process]] of [https://en.wikipedia.org/wiki/Speciation speciation]—where new varieties of [[organisms]] arise and thrive when they are able to find and exploit an [https://en.wikipedia.org/wiki/Ecological_niche ecological niche]—and species become extinct when they are no longer able [[to]] survive in changing conditions or against superior [[competition]]. A typical species becomes extinct within 10 million years of its first [[appearance]], although some [[species]], called [https://en.wikipedia.org/wiki/Living_fossil living fossils], [[survive]] virtually unchanged for hundreds of millions of years. Extinction, though, is usually a [[natural]] [[phenomenon]]; it is estimated that 99.9% of all species that have ever lived are now extinct.
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[https://en.wikipedia.org/wiki/Extinction_event Mass extinctions] are [[relatively]] rare [[events]]; however, isolated extinctions are quite common. Only recently have extinctions been [[recorded]] and [[scientists]] have become alarmed at the high rates of recent extinctions. It is estimated most [[species]] that go extinct have never been [[documented]] by scientists. Some scientists estimate that up to half of presently existing species may become extinct by 2100.[https://en.wikipedia.org/wiki/Extinction]
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[[Category: Biology]]

Latest revision as of 23:09, 12 December 2020

Lighterstill.jpg

Extinction.jpg

Etymology

Middle English, from Latin exstinctus, past participle of exstinguere

Definitions

  • 1 a : no longer burning
b : no longer active <an extinct volcano>
  • 2 : no longer existing <an extinct animal>
  • 3 a : gone out of use : superseded
b : having no qualified claimant <an extinct title>

Description

In biology and ecology, extinction is the end of an organism or group of taxa. The moment of extinction is generally considered to be the death of the last individual of that species (although the capacity to breed and recover may have been lost before this point). Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "re-appears" (typically in the fossil record) after a period of apparent absence.

Through evolution, new species arise through the process of speciation—where new varieties of organisms arise and thrive when they are able to find and exploit an ecological niche—and species become extinct when they are no longer able to survive in changing conditions or against superior competition. A typical species becomes extinct within 10 million years of its first appearance, although some species, called living fossils, survive virtually unchanged for hundreds of millions of years. Extinction, though, is usually a natural phenomenon; it is estimated that 99.9% of all species that have ever lived are now extinct.

Mass extinctions are relatively rare events; however, isolated extinctions are quite common. Only recently have extinctions been recorded and scientists have become alarmed at the high rates of recent extinctions. It is estimated most species that go extinct have never been documented by scientists. Some scientists estimate that up to half of presently existing species may become extinct by 2100.[1]