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　　出国留学网小编为大家带来英语听力音频：为什么贫瘠的地方生物多样性更丰富，以幽默诙谐的方式为你解答那些那些你意想不到的科学小知识，详细内容如下，和小编一起来看一下吧~

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　　A soccer-field sized patch of forest in frigid Alaska has about 40 different species of plants,compared with about 70 in temperate England and 300 in the Amazonian rain forest.These biodiversity differences hold true for entire countries,too:England has 1500 plant species,while tropical Guyana,9000.

　　在极其寒冷的阿拉斯加 一块足球场大小的森林大约含有40种物种，与之相比 较温和的英国约有70种 亚马逊雨林则有300种。这种生物多样性差异对国家同样适用;英国有1500种植物，而热带圭亚有9000种.

　　The super diversity of tropical rainforests is only equalled in one other type of ecosystem on Earth:scrubby fire-prone shrublands that grow in western Australia and southern Africa.These shrublands may not look as majestic as tropical rainforests,but in a given area,they're home to similarly stupendous numbers of species.

　　热带雨林的生物多样性 仅相当于地球上另一个生态系统 澳大利亚西部和非洲南部 易发火灾的低矮灌木地 这些灌丛或许看起来没有热带雨林那么壮观，但在相同面积下 它们所包含的物种数是一样的。

　　Which doesn't necessarily mean that the rainforests and shrublands are easy places for plants to live.In fact,both ecosystems owe their enormous diversity,in part.to the fact that their soils have critically low supplies of nitrogen and especially phosphorus,nutrients plants need in order to grow.

　　这并不意味着热带雨林和灌丛是适宜植物生长的地方。事实上 这两个系统都不该拥有这么多物种，它们的...

　　下面是出国留学网小编为大家带来的英语听力音频：人类跟黑猩猩DNA相似度真的有99%。希望能对大家的英语口语和听力练习有所帮助!

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　　It's often said that we humans share 50 percent of our DNA with bananas,80 percent with dogs,and 99 percent with chimpanzees.Taken literally,those numbers make it sound like we could pluck one cell from a chimp and one from a human,pull out the tangle bundles of DNA known as chromosomes,unroll each on elike a scroll,and read off two nearly identical strings of letters.

　　人们常说 人类DNA与香蕉DNA的相识度50%，与狗的相似度80% 与黑猩猩相似度99%。这听起来就好像 我们可以从猩猩和人类身上各取一个细胞，拖出染色体上缠成一团的DNA，展成卷轴状，然后读取出两列几乎一样的字母排序。

　　But in reality,the human and chimp scrolls don't sync up so easily.In the six to eight million years since we split from our last common ancestor,chance mutations and natural selection have changed each of our genomes in radical-and unique-ways.

　　但事实上，人类和黑猩猩的卷轴并没那么同步。在我们从最后一位共同祖先分化之后的6-8百万年间，突变和自然选择以独特的方式彻底地改变了我们的基因组。

　　Two human scrolls fused,leaving us with 23 pairs of chromosomes to chimps' 24.Other large mutations revised huge sections of text-duplicating a chunk of a human DNA here.erasing a chunk of chimp DNA there-while throughout the scrolls,tiny mutations swapped one letter for another.When researchers sat down to compare the chimp and human genomes,those sing...