原因很容易理解：在自然界中，现存的生物要么适应环境，要么被新物种取代。

The reason for this is easy to recognise: in nature, the existent organisms either adapt or are regularly replaced by new types.

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它们进化到能够识别出几种基本的味道，以便快速辨别毒素，而毒素在自然界中通常是很苦或很酸的。

They evolved to recognise only a few basic tastes in order to quickly identify toxins, which in nature are often quite bitter or acidly sour.

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在自然界中，它们经常在山顶和悬崖边筑巢。

In nature, they often nest on mountaintops and on the sides of cliffs .

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Again, these plasmids occur naturally in nature; they were discovered particularly in micro-organisms have plasmids that confer biological properties onto them.

此外,质粒存在于自然界中,质粒是在微生物中发现的,它们也赋予了微生物一些生物学特性

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They're out there, you can gather them, you can hunt them, you can fish them, or you can grow them, you can do something but it's out there in nature.

它们就存在于自然界,可以采集,可以通过狩猎获取,可以垂钓,或者种植它们,它们就在自然界中,只要你取之有道

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So, a natural product is something that is made by nature, and often natural products, whether it comes from a plant or a marine organism have some really good, useful properties. And so, one particular compound has anti-tumor properties. So, again, along this line of cancer research.

天然产物是在自然界中生成的,通常一个天然产物，不管是来自植物或者海洋生物,都有些非常好非常实用的性质，其中的一个特殊的化合物,可以治疗癌症,再一次我们又来到癌症研究上。

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