State of Species Extinction: Difference between revisions

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(Created page with "A State of Species Extinction is a state of extinction for an animal species. * <B>See:</B> Holocene Extinction, Animal Well-Being, Functional Extinction...")
 
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==References==
 
== References ==


=== 2019 ===
=== 2019 ===
* (Wikipedia, 2019) &rArr; https://en.wikipedia.org/wiki/Extinction Retrieved:2019-9-9.
* (Wikipedia, 2019) ⇒ https://en.wikipedia.org/wiki/Extinction Retrieved:2019-9-9.
** In [[biology]], '''extinction''' is the termination of a kind of [[organism]] or of a group of kinds ([[taxon]]), usually a [[species]]. The moment of extinction is generally considered to be the death of the [[endling|last individual]] of the species, although the [[Functional extinction|capacity to breed and recover]] may have been lost before this point. Because a species' potential [[Range (biology)|range]] may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as [[Lazarus taxon|Lazarus taxa]], where a species presumed extinct abruptly "reappears" (typically in the [[fossil|fossil record]]) after a period of apparent absence. <P> More than 99 percent of all species, amounting to over five billion species,<ref name="Book-Biology"></ref> that ever [[Life|lived]] on Earth are estimated to have died out.<ref name="StearnsStearns2000"></ref> <ref name="NYT-20141108-MJN"></ref> <ref name="Newman" /> Estimates on the number of Earth's current species range from 10 million to 14 million,<ref name="MillerSpoolman2012"></ref> of which about 1.2 million have been documented and over 86 percent have not yet been described.<ref name="PLoS-20110823"></ref> In 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one thousandth of one percent described.<ref name="NSF-2016002"></ref> <P> Through [[evolution]], 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 (biology)|competition]]. The relationship between animals and their ecological niches has been firmly established.<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"></ref> A typical species becomes extinct within 10 million years of its first appearance,<ref name="Newman"></ref> although some species, called [[living fossil]]s, survive with virtually no [[morphology (biology)|morphological]] change for hundreds of millions of years. <P> [[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 [[Holocene extinction#Defaunation|current high rate of extinctions]].<ref name="MSNBC">[http://www.msnbc.msn.com/id/6502368/ Species disappearing at an alarming rate, report says]. [[MSNBC]]. Retrieved July 26, 2006. </ref> <ref> ([[PBS Digital Studios]], November 17, 2014) </ref>  Most species that become extinct are never scientifically documented. Some scientists estimate that up to half of presently existing plant and animal species may become extinct by 2100.<ref name="Wilson">[[E.O. Wilson|Wilson, E.O.]], ''The Future of Life'' (2002) (). See also: [[Richard Leakey|Leakey, Richard]], ''The Sixth Extinction : Patterns of Life and the Future of Humankind'', </ref> A 2018 report indicated that the [[Phylogenetics|phylogenetic diversity]] of 300 mammalian species erased during the human era since the [[Late Pleistocene]] would require 5 to 7 million years to recover.<ref name="davis2018"></ref> According to the 2019 ''[[Global Assessment Report on Biodiversity and Ecosystem Services]]'' by [[IPBES]], the biomass of wild mammals has fallen by 82%, natural ecosystems have lost about half their area and a million species are at risk of extinction—all largely as a result of human actions. Twenty-five percent of plant and animal species are threatened with extinction.  <ref name="NYT-20190506"></ref> <ref name="IPBES-20190506"></ref> In June 2019, one million species of plants and animals were at risk of extinction. At least 571 species are lost since 1750 but likely many more. The main cause of the extinctions is the destruction of natural habitats by human activities, such as cutting down forests and converting land into fields for farming. <ref> [https://www.theguardian.com/environment/2019/jun/10/frightening-number-of-plant-extinctions-found-in-global-survey ‘Frightening’ number of plant extinctions found in global survey] The Guardian 10 Jun 2019 </ref> <P> A [[Dagger (typography)|dagger symbol]] (†) placed next to the name of a species or other taxon normally indicates its status as extinct.
** In [[biology]], '''extinction''' is the termination of a kind of [[organism]] or of a group of kinds ([[taxon]]), usually a [[species]]. The moment of extinction is generally considered to be the death of the [[endling|last individual]] of the species, although the [[Functional extinction|capacity to breed and recover]] may have been lost before this point. Because a species' potential [[Range (biology)|range]] may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as [[Lazarus taxon|Lazarus taxa]], where a species presumed extinct abruptly "reappears" (typically in the [[fossil|fossil record]]) after a period of apparent absence. <P> More than 99 percent of all species, amounting to over five billion species,<ref name="Book-Biology"></ref> that ever [[Life|lived]] on Earth are estimated to have died out.<ref name="StearnsStearns2000"></ref> <ref name="NYT-20141108-MJN"></ref> <ref name="Newman" /> Estimates on the number of Earth's current species range from 10 million to 14 million,<ref name="MillerSpoolman2012"></ref> of which about 1.2 million have been documented and over 86 percent have not yet been described.<ref name="PLoS-20110823"></ref> In 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one thousandth of one percent described.<ref name="NSF-2016002"></ref> <P> Through [[evolution]], 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 (biology)|competition]]. The relationship between animals and their ecological niches has been firmly established.<ref name="SahneyBentonFerry2010LinksDiversityVertebrates"></ref> A typical species becomes extinct within 10 million years of its first appearance,<ref name="Newman"></ref> although some species, called [[living fossil]]s, survive with virtually no [[morphology (biology)|morphological]] change for hundreds of millions of years. <P> [[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 [[Holocene extinction#Defaunation|current high rate of extinctions]].<ref name="MSNBC">[http://www.msnbc.msn.com/id/6502368/ Species disappearing at an alarming rate, report says]. [[MSNBC]]. Retrieved July 26, 2006. </ref> <ref> ([[PBS Digital Studios]], November 17, 2014) </ref>  Most species that become extinct are never scientifically documented. Some scientists estimate that up to half of presently existing plant and animal species may become extinct by 2100.<ref name="Wilson">[[E.O. Wilson|Wilson, E.O.]], ''The Future of Life'' (2002) (). See also: [[Richard Leakey|Leakey, Richard]], ''The Sixth Extinction : Patterns of Life and the Future of Humankind'', </ref> A 2018 report indicated that the [[Phylogenetics|phylogenetic diversity]] of 300 mammalian species erased during the human era since the [[Late Pleistocene]] would require 5 to 7 million years to recover.<ref name="davis2018"></ref> According to the 2019 ''[[Global Assessment Report on Biodiversity and Ecosystem Services]]'' by [[IPBES]], the biomass of wild mammals has fallen by 82%, natural ecosystems have lost about half their area and a million species are at risk of extinction—all largely as a result of human actions. Twenty-five percent of plant and animal species are threatened with extinction.  <ref name="NYT-20190506"></ref> <ref name="IPBES-20190506"></ref> In June 2019, one million species of plants and animals were at risk of extinction. At least 571 species are lost since 1750 but likely many more. The main cause of the extinctions is the destruction of natural habitats by human activities, such as cutting down forests and converting land into fields for farming. <ref> [https://www.theguardian.com/environment/2019/jun/10/frightening-number-of-plant-extinctions-found-in-global-survey ‘Frightening’ number of plant extinctions found in global survey] The Guardian 10 Jun 2019 </ref> <P> A [[Dagger (typography)|dagger symbol]] (†) placed next to the name of a species or other taxon normally indicates its status as extinct.
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Revision as of 11:56, 9 September 2019

A State of Species Extinction is a state of extinction for an animal species.

References

2019

  • (Wikipedia, 2019) ⇒ https://en.wikipedia.org/wiki/Extinction Retrieved:2019-9-9.
    • In biology, extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the 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 "reappears" (typically in the fossil record) after a period of apparent absence.

      More than 99 percent of all species, amounting to over five billion species,[1] that ever lived on Earth are estimated to have died out.[2] [3] [4] Estimates on the number of Earth's current species range from 10 million to 14 million,[5] of which about 1.2 million have been documented and over 86 percent have not yet been described.[6] In 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one thousandth of one percent described.[7]

      Through evolution, 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. The relationship between animals and their ecological niches has been firmly established.[8] A typical species becomes extinct within 10 million years of its first appearance,[4] although some species, called living fossils, survive with virtually no morphological change for hundreds of millions of years.

      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 current high rate of extinctions.[9] [10] Most species that become extinct are never scientifically documented. Some scientists estimate that up to half of presently existing plant and animal species may become extinct by 2100.[11] A 2018 report indicated that the phylogenetic diversity of 300 mammalian species erased during the human era since the Late Pleistocene would require 5 to 7 million years to recover.[12] According to the 2019 Global Assessment Report on Biodiversity and Ecosystem Services by IPBES, the biomass of wild mammals has fallen by 82%, natural ecosystems have lost about half their area and a million species are at risk of extinction—all largely as a result of human actions. Twenty-five percent of plant and animal species are threatened with extinction. [13] [14] In June 2019, one million species of plants and animals were at risk of extinction. At least 571 species are lost since 1750 but likely many more. The main cause of the extinctions is the destruction of natural habitats by human activities, such as cutting down forests and converting land into fields for farming. [15]

      A dagger symbol (†) placed next to the name of a species or other taxon normally indicates its status as extinct.

  1. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Book-Biology
  2. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named StearnsStearns2000
  3. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named NYT-20141108-MJN
  4. ↑ 4.0 4.1 Cite error: Invalid <ref> tag; no text was provided for refs named Newman
  5. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named MillerSpoolman2012
  6. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named PLoS-20110823
  7. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named NSF-2016002
  8. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named SahneyBentonFerry2010LinksDiversityVertebrates
  9. ↑ Species disappearing at an alarming rate, report says. MSNBC. Retrieved July 26, 2006.
  10. ↑ (PBS Digital Studios, November 17, 2014)
  11. ↑ Wilson, E.O., The Future of Life (2002) (). See also: Leakey, Richard, The Sixth Extinction : Patterns of Life and the Future of Humankind,
  12. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named davis2018
  13. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named NYT-20190506
  14. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named IPBES-20190506
  15. ↑ ‘Frightening’ number of plant extinctions found in global survey The Guardian 10 Jun 2019
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