Extinct Turkic peoples

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% of all species that ever lived on Earth, amounting to over five billion species, are estimated to have died out. It is estimated that there are currently around 8.7 million species of eukaryote globally, and possibly many times more if microorganisms, like bacteria, are included. Notable extinct animal species include non-avian dinosaurs, saber-toothed cats, dodos, mammoths, ground sloths, thylacines, trilobites, and golden toads.

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. A typical species becomes extinct within 10 million years of its first appearance, although some species, called living fossils, survive with little to no morphological change for hundreds of millions of years.

Mass extinctions 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 and scientists have become alarmed at the current high rate of extinctions. 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. Wilson, E.O., ''The Future of Life'' (2002) (). See also: Leakey, Richard, ''The Sixth Extinction : Patterns of Life and the Future of Humankind'', 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.

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. 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 species have been 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.

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

Examples

Examples of species and subspecies that are extinct include:

* Dodo
* Chinese paddlefish (last seen in 2003; declared extinct in 2022)
* Great auk (last confirmed pair was killed in the 1840s)
* Thylacine (last known member died in captivity in 1936; unconfirmed sightings continued after this date)
* Kauai O'o (last known member was heard in 1987; the entire Mohoidae became extinct with it)
* Spectacled cormorant (last known members were said to live in the 1850s)
* Carolina parakeet (last known member named Incas died in captivity in 1918; declared extinct in 1939)
* Passenger pigeon (last known member named Martha died in captivity in 1914)
* Tasmanian emu
* Kangaroo Island emu
* King island emu
* Haast's eagle