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Permian–Triassic extinction event 252 Ma Large igneous province (LIP) eruptions [ 23 ] from the Siberian Traps , [ 24 ] an impact event (the Wilkes Land Crater ), [ 25 ] an Anoxic event , [ 26 ] an Ice age , [ 27 ] or other possible causes
Asteroid impacts: one large impact is associated with a mass extinction, that is, the Cretaceous–Paleogene extinction event; there have been many smaller impacts but they are not associated with significant extinctions, [105] or cannot be dated precisely enough.
This is much faster than the expected “background” extinction rate, or the rate at which species would naturally die off without outside influence — in the absence of human beings, these 73 ...
The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes. Researchers have identified five other major extinction events in Earth's history, with estimated losses below: [11] End Ordovician: 440 million years ago, 86% of all species lost, including graptolites
Extinctions are a normal part of the evolutionary process, and the background extinction rate is a measurement of "how often" they naturally occur. Normal extinction rates are often used as a comparison to present day extinction rates, to illustrate the higher frequency of extinction today than in all periods of non-extinction events before it. [1]
Here are 10 of the most devastating animal extinctions in recent history, plus a closer look at the dire impact of human greed and why we need stronger wildlife protection measures.
The following list is incomplete by necessity, since the majority of extinctions are thought to be undocumented, and for many others there isn't a definitive, widely accepted last, or most recent record. According to the species-area theory, the present rate of extinction may be up to 140,000 species per year. [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). Some of the many possible contributors to anthropogenic hazard are climate change, global nuclear ...