Paleontologists have identified in the past history of earth five large extinction episodes. The latest that happened 75 millions years ago and wiped out the dinosaurs was provoked by the fall of a large meteor near the Yucatan peninsula. A new large scale extinction is happening right now. Scientists estimate that the extinction rate is 1000 times greater today than in pre-industrial era and that in 2050 3% of all known species will have disappeared. This is known as the sixth extinction. And for the first time it is provoked by a human cataclysm and not by a geological one.
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