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是什么因素导致了“寒武纪大爆发”事件的产生?得到很多人认同的一种观点是“含氧量变异说”。该理论认为,距今大约20亿年前,由于行光合作用的水生原核生物出现,导致水圈和大气圈中的自由氧积累和紫外线辐射作用减弱。距今
What led to the “Cambrian explosion” event? Many people agree that one view is “variation of oxygen content ”. The theory suggests that about 2 billion years ago, the photosynthesis of aquatic prokaryotes led to a decrease in free oxygen accumulation and UV radiation in the hydrosphere and the atmosphere. Now