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Nuclear war is an often-predicted cause of the extinction of humankind. [1]Human extinction or omnicide is the hypothetical end of the human species, either by population decline due to extraneous natural causes, such as an asteroid impact or large-scale volcanism, or via anthropogenic destruction (self-extinction), for example by sub-replacement fertility.
Earth has experienced numerous mass extinction events, in which up to 96% of all species present at the time were eliminated. [112] A notable example is the K-T extinction event, which killed the dinosaurs. The types of threats posed by nature have been argued to be relatively constant, though this has been disputed. [113]
The earliest evidence for life on Earth includes: 3.8 billion-year-old biogenic hematite in a banded iron formation of the Nuvvuagittuq Greenstone Belt in Canada; [30] graphite in 3.7 billion-year-old metasedimentary rocks in western Greenland; [31] and microbial mat fossils in 3.48 billion-year-old sandstone in Western Australia.
As scientists have discerned from fossil records, species on Earth have already passed through five mass extinction events in the planet’s lifetime, including the last mass extinction roughly 65 ...
The estimated end of the Sun's current phase of development, after which it will swell into a red giant, either scorching or swallowing Earth, will occur around five billion years from now. However, as the Sun grows gradually hotter (over millions of years), Earth may become too hot for life as early as one billion years from now. [207] [208] [209]
Your gut is endangered. And that’s not a good thing for your health—or the health of the rest of the world.
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
Examples of non-anthropogenic risks are an asteroid or comet impact event, a supervolcanic eruption, a natural pandemic, a lethal gamma-ray burst, a geomagnetic storm from a coronal mass ejection destroying electronic equipment, natural long-term climate change, hostile extraterrestrial life, or the Sun transforming into a red giant star and ...