Extinction

Extinction is the termination of an <a href="/facts/Organism/j8JkL09u">organism</a> by the <a href="/facts/Death/VJmq29qm">death</a> of its <a href="/facts/Endling/IsIjFdQ3">last member</a>. A <a href="/facts/Taxon/caQC1e87">taxon</a> may become <a href="/facts/Functional_extinction/vQpvCCys">functionally extinct</a> before the death of its last member if it loses the capacity to <a href="/facts/Reproduction/nNu0F5Dy">reproduce</a> and recover. As a <a href="/facts/Species/oDg6b96r">species</a>' potential <a href="/facts/Range_(biology)/SAI9lJq9">range</a> may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as <a href="/facts/Lazarus_taxon/loReFtoA">Lazarus taxa</a>, where a species presumed extinct abruptly "reappears" (typically in the <a href="/facts/Fossil/by7NzIA1">fossil record</a>) after a period of apparent absence.
Over five billion species are estimated to have <a href="/facts/Died/VJmq29qm">died</a> out. It is estimated that there are currently around 8.7 million species of <a href="/facts/Eukaryote/SkwyPLMA">eukaryotes</a> globally, possibly many times more if <a href="/facts/Microorganism/pysJYcE2">microorganisms</a> are included. Notable extinct animal species include <a href="/facts/Dinosaur/JRdMqBnq">non-avian dinosaurs</a>, <a href="/facts/Machairodontinae/WeSTUlXF">saber-toothed cats</a>, and <a href="/facts/Mammoth/k9MnxS2k">mammoths</a>. Through <a href="/facts/Evolution/Hj0qAaBk">evolution</a>, species arise through the process of <a href="/facts/Speciation/pmRTQbTK">speciation</a>. Species become extinct when they are no longer able to survive in changing conditions or against superior <a href="/facts/Competition_(biology)/3xN0IynL">competition</a>. The relationship between animals and their ecological niches has been firmly established. A typical species becomes extinct within 10 million years of its first appearance, although some species, called <a href="/facts/Living_fossil/EujFvU2D">living fossils</a>, survive with little to no <a href="/facts/Morphology_(biology)/Nl3B0myy">morphological</a> change for hundreds of millions of years.
<a href="/facts/Extinction_event/HloJubtR">Mass extinctions</a> are relatively rare events; however, isolated extinctions of species and clades are quite common, and are a natural part of the evolutionary process. Only recently have extinctions been recorded with scientists alarmed at the <a href="/facts/Holocene_extinction/C1LzDDy7">current high rate of extinctions</a>. 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. A 2018 report indicated that the <a href="/facts/Phylogenetics/bw4rsovt">phylogenetic diversity</a> of 300 mammalian species erased during the human era since the <a href="/facts/Late_Pleistocene/jKVh7yXL">Late Pleistocene</a> would require 5 to 7 million years to recover.
According to the 2019 <a href="/facts/Global_Assessment_Report_on_Biodiversity_and_Ecosystem_Services/WDjaKfqm">Global Assessment Report on Biodiversity and Ecosystem Services</a> by <a href="/facts/IPBES/kBrrIDp1">IPBES</a>, 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 <a href="/facts/Threatened_species/kryGsxNb">threatened</a> with extinction. In a subsequent report, IPBES listed unsustainable fishing, hunting and logging as being some of the primary drivers of the global extinction crisis. In June 2019, one million species of plants and animals were at risk of extinction. At least 571 plant species have been lost since 1750. 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.
A <a href="/facts/Dagger_(mark)/lDNNgbgr">dagger symbol</a> (†) placed next to the name of a species or other taxon normally indicates its status as extinct.

Extinction open-in-new

Extinction