At some point later, through natural occurrence or human intervention, that tree became horizontal.

稍晚的时间，因为自然过程或者人为干涉，树倒了。

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Mimicry arises as the result of evolution through natural selection and the occurrence of random genetic mutations that lead over many generations to the appearance of favorable characteristics.

拟态是无数代自然选择和遗传变异的进化而获得的有利特征的结果。

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Tonight's rare lunar occurrence, when Earth's natural satellite is only a mere 356, 575 kilometers out in orbit, brings the moon to its closest position to Earth.

今天晚上地球的天然卫星月球在其轨道上离地球仅有356575公里远，这使得月球处于离地球最近的位置上，而这也是极为罕见的有关月球的事件。

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The occurrence of natural disasters over the last couple of years has increased awareness of the need for data protection and disaster recovery.

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The EAW said the heat-related deaths were a natural occurrence, not uncommon, which started in Mid May.

BBC: Cockle deaths blamed on weather

The mutation is a natural occurrence, as is the reaction to the drug.

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