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野生动物绝灭的几种原因自然绝灭从进化观点看,任何一种动物都要经历产生、发展和衰亡的过程。根据化石分析,鸟类一个种的平均寿命约为200万年,兽类约为60万年。自然绝灭可以是一个种的直接绝灭,也可以是由旧种逐渐进化为新种。在目前我国动物学家对大熊猫濒危原因的争论中,一种论点就认为它是一个古老的物种,由于过于特化,繁殖能力低不能适应环境的变
Several causes of the extinction of wild animals Natural extinction From an evolutionary point of view, any animal has to undergo a process of generation, development, and decline. According to fossil analysis, the average life span of one species of birds is about 2 million years, and that of beasts is about 600,000 years. Natural extinction can be a direct extinction of a species, or it can be gradually evolved from the old species to a new species. In the current controversy over the endangered cause of giant pandas by our country’s zoologists, one argument is that it is an ancient species. Due to over-specialization, low reproductive capacity cannot adapt to changes in the environment.