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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
The End Permian extinction or the "Great Dying" occurred at the Permian–Triassic transition. [13] It was the Phanerozoic Eon's largest extinction: 53% of marine families died, 84% of marine genera, about 81% of all marine species [14] and an estimated 70% of terrestrial vertebrate species. [15]
The Cretaceous–Paleogene (K–Pg) extinction event, [a] also known as the K–T extinction, [b] was the mass extinction of three-quarters of the plant and animal species on Earth [2] [3] approximately 66 million years ago. The event caused the extinction of all non-avian dinosaurs.
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]
Great Oxidation Event led by cyanobacteria's oxygenic photosynthesis – various forms of Archaea and anoxic bacteria become extinct in first great extinction event on Earth. Algoman Orogeny or Kenoran: assembly of Arctica out of the Canadian Laurentian Shield and Siberian craton – formation of Angaran Shield and Slave Province.
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A new analysis on Europe’s IUCN Red List numbers finds that one-fifth of threatened species face the risk of extinction. The study had also found the major threat to be agricultural land use.
Luis (left) and his son Walter Alvarez (right) at the K-Pg Boundary in Gubbio, Italy, 1981. In 1980, a team of researchers led by Nobel prize-winning physicist Luis Alvarez, his son, geologist Walter Alvarez, and chemists Frank Asaro and Helen Vaughn Michel discovered that sedimentary layers found all over the world at the Cretaceous–Paleogene boundary contain a concentration of iridium ...