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A growing number of scientists believe a sixth mass extinction event of a magnitude equal to the prior five has been unfolding for the past 10,000 years as humans have made their mark around the ...
It occurs when the rate of extinction increases with respect to the background extinction rate [1] and the rate of speciation. Estimates of the number of major mass extinctions in the last 540 million years range from as few as five to more than twenty.
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
Scientists have speculated for years that the world is coming up on its sixth mass extinction, when a majority of the Earth’s creatures become extinct. But a couple of Virginia Tech researchers ...
The second mass extinction was the Late Devonian extinction, probably caused by the evolution of trees, which could have led to the depletion of greenhouse gases (like CO 2) or the eutrophication of water. 70% of all species became extinct. [179] The third mass extinction was the Permian-Triassic, or the Great Dying, event.
Colossal Biosciences, which aims to revive extinct species, has raised an additional $200 million. Critics say de-extinction in its purest sense isn’t possible.
Extinction may occur a long time after the events that set it in motion, a phenomenon known as extinction debt. Assessing the relative importance of genetic factors compared to environmental ones as the causes of extinction has been compared to the debate on nature and nurture . [ 37 ]
From around 1850 to 1980, most geologists endorsed uniformitarianism ("The present is the key to the past") and gradualism (geologic change occurs slowly over long periods of time) and rejected the idea that cataclysmic events such as earthquakes, volcanic eruptions, or floods of vastly greater power than those observed at the present time ...