Animal and plant species are currently going extinct at a rate that has not been seen since the last mass extinction.
The
Holocene extinction, otherwise referred to as the
sixth mass extinction or
Anthropocene extinction, is an ongoing
extinction event of
species during the present
Holocene epoch (with the more recent time sometimes called
Anthropocene) as a result of
human activity.
[3][4][5] The included extinctions span numerous families of
plants[6] and
animals, including
mammals,
birds,
reptiles,
amphibians,
fishes and
invertebrates. With widespread degradation of
highly biodiverse habitats such as
coral reefs and
rainforests, as well as other areas, the vast majority of these extinctions are thought to be
undocumented, as the species are undiscovered at the time of their extinction, or no one has yet discovered their extinction. The current rate of extinction of species is estimated at 100 to 1,000 times higher than
natural background extinction rates.
[4][7][8][9][10][11]
The Holocene extinction includes the disappearance of large land animals known as
megafauna, starting at the end of the
last glacial period. Megafauna outside of the African mainland, which did not evolve alongside humans, proved highly sensitive to the introduction of new
predation, and many died out shortly after early humans began spreading and hunting across the Earth
[12][13] (many
African species have also gone extinct in the Holocene, but – with few exceptions – megafauna of the mainland was largely unaffected until a few hundred years ago).
[14] These extinctions, occurring near the
Pleistocene–
Holocene boundary, are sometimes referred to as the
Quaternary extinction event.
The most popular theory is that human overhunting of species added to existing stress conditions as the extinction coincides with human emergence. Although there is debate regarding how much human predation affected their decline, certain population declines have been directly correlated with human activity, such as the extinction events of
New Zealand and
Hawaii. Aside from humans,
climate change may have been a driving factor in the megafaunal extinctions, especially at the end of the Pleistocene.
Ecologically, humanity has been noted as an unprecedented "global superpredator"
[15] that consistently preys on the adults of other
apex predators, and has
worldwide effects on
food webs. There have been extinctions of species on every
land mass and in every
ocean: there are many famous examples
within Africa,
Asia,
Europe,
Australia,
North and
South America, and on smaller islands. Overall, the Holocene extinction can be linked to the
human impact on the environment. The Holocene extinction continues into the 21st century, with
meat consumption,
overfishing, and
ocean acidification and the
decline in amphibian populations[16] being a few broader examples of a
cosmopolitan decline in biodiversity.
Human population growth and
increasing per capita consumption are considered to be the primary drivers of this decline.
[11][17][18][19]
The 2019
Global Assessment Report on Biodiversity and Ecosystem Services, published by the
United Nations'
Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, posits that roughly one million species of plants and animals face extinction within decades as the result of human actions.
[19][20][21][22] Organized human existence is jeopardized by increasingly rapid destruction of the systems that support life on Earth, according to the report, the result of one of the most comprehensive studies of the health of the planet ever conducted.
[23]
en.wikipedia.org
.
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