# Extinction

| Conservation status bi IUCN Reid Leet category |
| --- |
|  |
| Extinct |
| * Extinct (EX)
* Extinct in the Wild (EW)
 | * (leet)
* (leet)
 |
| Threitent |
| * Creetically Endangered (CR)
* Endangered (EN)
* Vulnerable (VU)
 | * (leet)
* (leet)
* (leet)
 |
| *Lawer Risk* |
| * Near Threitent (NT)
* Conservation Dependent (CD)
* Least Concern (LC)
 | * (leet)
* (leet)
 |
|

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**Other categories** |
| * Data Deficient (DD)
* Nae Evaluatit (NE)
 | * (list)
 |
|

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**Relatit topics Internaitional Union for the Conservation o Naitur (IUCN)
* IUCN Reid Leet
* NatureServe status
* Leets o organisms bi population
 |
|

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 Comparison o Reid leet clesses abuin an NatureServe status below  |
| * v
* t
* e
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In biology an ecology, **extinction** is the end o an organism or o a group o organisms (taxon), normally a speshies. The moment o extinction is generally conseedert tae be the daith o the last individual o the species, awtho the capacity tae breed an rekiver mey hae been lost afore this pynt. Acause a species' potential range mey be verra lairge, determinin this moment is difficult, an is uisually duin retrospectively. This difficulty leads tae phenomena sic as Lazarus taxa, whaur a speshies presumed extinct abruptly "reappears" (teepically in the fossil record) efter a period o apparent absence.

Mair nor 99 percent o aw speshies, amoontin tae ower five billion speshies, that iver leeved on Yird are estimatit tae hae dee'd oot. Estimates on the nummer o Yird's current species range frae 10 million tae 14 million, o that aboot 1.2 million hae been documentit an ower 86 percent hae nae yet been descrived. In 2016, scientists reportit that 1 trillion speshies are estimatit tae be on Yird the noo wi anerly ane thoosandt o ane percent descrived.

Throu evolution, speshies arise throu the process o speciation—whaur new varieties o organisms arise an thrive whan thay are able tae find an exploit an ecological niche—an speshies become extinct whan thay are nae langer able tae survive in chyngin condeetions or agin superior competeetion. The relationship atween ainimals an thair ecological niches haes been firmly established. A teepical speshies becomes extinct within 10 million years o its first appearance, awtho some speshies, cried leevin fossils, survive wi little tae nae morphological chynge for hunners o millions o years.

Mass extinctions are relatively rare events; houiver, isolatit extinctions are quite common. Anerly recentlik hae extinctions been recordit an scientists hae become alairmed at the current heich rate o extinctions. Maist speshies that become extinct are niver scienteefically documentit. Some scientists estimate that up tae hauf o presently existin plant an ainimal speshies mey become extinct bi 2100. A 2018 report indicatit that the phylogenetic diversity o 300 mammalian speshies erased in the human era syne the Late Pleistocene wad require 5 tae 7 million years tae rekiver.

Accordin tae the 2019 *Global Assessment Report on Biodiversity an Ecoseestem Services* bi IPBES, the biomass o wild mammals haes fawen bi 82%, naitural ecoseestems hae lost aboot hauf thair area an a million speshies are at risk o extinction—aw lairgely as a result o human actions. Twinty-five percent o plant an ainimal species are threitent wi extinction.

In Juin 2019, ane million speshies o plants an ainimals war at risk o extinction. At least 571 speshies are lost syne 1750 but likely mony mair. The main cause o the extinctions is the destruction o naitural habitats bi human acteevities, sic as cuttin doun forests an convertin laund intae fields for fermin.

A dagger seembol (†) placed next tae the name o a speshies or ither taxon normally indicates its status as extinct.