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Deeper in time, a mass extinction event that ended the Devonian Period, a geological era when life thrived on land for the first time, was also attributed to a hyperthermal event likely triggered ...
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
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.
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
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 ...
Researchers assessed the status of 23,496 species of freshwater animals in groups including fishes, crustaceans such as crabs, crayfish and shrimp and insects such as dragonflies and damselflies ...
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.
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 ]