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第一次,在距今4.4亿年前的奥陶纪末期,地球史上第三大的物种灭绝事件,约85%的物灭亡。古生物学家认为,这次物种灭绝是由全球气变冷造成的。在大约4.4亿年前,现在的撒哈拉在的陆地曾经位于南极,当陆地汇集在极点附近容易造成厚厚的积冰---奥陶纪正是这种情形大片的冰川使洋流和大气环流变冷,整个地球的度下降了,冰川锁住了水,海平面也降低了,原丰富的沿海生物圈被破坏了,导致了85%的物灭绝。
For the first time, about 85% of all objects died in the extinction of the third largest species in Earth’s history at the end of Ordovician 440 million years ago. Paleontologists believe that the extinction of this species was caused by global cooling. About 440 million years ago, the present Sahara land was once located in Antarctica, where thick ice accumulates near the poles of Ordos. It is the glaciers of this type that make ocean currents and atmospheric circulation colder, The degree of earth has dropped, the glaciers have locked in water and the sea level has also dropped, and the original rich coastal biosphere has been destroyed, leading to the extinction of 85% of the matter.