亚洲并非棕榈树的原产地，在这儿传统上用手工为棕榈树传递花粉，这种办法使棕榈果实产量非常低。当1980年将作为棕榈花的有效授粉者而被熟知的象鼻虫引进亚洲后，棕榈果的产量上升——在某些地区上升了50%——但在1984年急剧下降。
以下哪一项，如果是正确的，将对1984年产量的下降提出最好的解释？（）

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• Madagascar

  There are at least 8 million unique species of life on the planet, if net far more, and you could be forgiven for believing that all of them can be found in Andasibe. Walking through this rain forest in Madagascar is like stepping into the library of life. Sunlight seeps through the silky fringes of the Ravenea louvelii, an endangered palm (棕榈树) found, like so much else on this African island, nowhere else.

  Madagascar which separated from India 80 million to 100 million years ago before eventually settling off the southeastern coast of Africa, is in many ways an Earth apart. All that time in geographic isolation made Madagascar a Darwinian playground, its animals and plants evolving into forms utterly original. Some 90% of the island's plants and about 70% of its animals arc endemic, meaning that they arc found only in Madagascar. But what makes life on the island unique also makes it uniquely vuhnerable, which means if we lose these animals on Madagascar, they're gone forever.

  That loss seems likelier than ever because the animals are under threat as never before. Once lushly forested, Madagascar has seen more than 80% of its original vegetation cut down or burned since humans arrived at least 1500 years ago, fragmenting habitats and leaving animals effectively homeless. Unchecked hunting wiped out a number of large species, and today mining, logging and energy exploration threaten those that remain. It has an area the size of New Jersey in Madagascar that is still under forest, and all this incredible diversity is crammed into it.

  Madagascar is a conservation hot spot a term for a region that is very biodiverse and particularly threatened--and while that makes the island special, it is hardly alone. Conservationists estimate that extinctions worldwide are occurring at a pace that is up to 1 000 times as great as history's background rate before human beings began scattering. Worse, that die-off could be accelerating.

  Price of Extinction

  There have been five extinction waves in the planet's history—including the Permian (二叠纪的) extinction 250 million years ago, when an estimated 70% of all terrestrial animals and 96 % of all marine creatures vanished, and, most recently, the Cretaceous (白垩纪的) event 65 million ),ears ago, which ended the reign of the dinosaurs. Though scientists have directly assessed the viability of fewer than 3% of the world's described species, the sample polling of animal populations so far suggests that we may have entered what will be the planet's sixth great extinction wave. And this time the cause isn't an unsteady planet or volcanoes. It's us.

  Through our growing numbers, our thirst for natural resources and, most of all, climate change-- which, by one reckoning, could help carry off 20% to 30% of all species before the end of the century-- we're shaping an Earth that will be biologically exhausted. A 2008 assessment by the: International Union for Conservation of Nature found that nearly 1 in 4 mammals worldwide were at risk for extinction, including endangered species. Over fishing and acidification of the oceans are threatening marine species as diverse as the corals.

  Scary for conservationists, yes. but the question arises: Why should it matter to the rest of us? After all, nearly all the species that were ever alive in the past are gone today. Evolution demands extinction. When we're using the term extinction to talk about the fate of the US auto industry, does it really matter if we lose species like the Yangtze River dolphin and the golden toad, all of which have effectively disappeared in recent years? What docs the loss of a few species among millions matter?

  For one thing, we're animals too, dependent on this planet like every other form. of life. The more species living in an ecosystem, the healthier and more productive it is, which matters for us--a recent study by the World Wildlife Fund (WWF) e

  A．At least 8 million unique species of life.

  B．More than 8 million unique species of life.

  C．A library of life

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• 阅读理解。

  初冬

  　　初冬是蛮不讲理的，她拉着风婆婆闯了过来，有恃无恐地把太阳公公驱逐到远方。太阳公公叹着气走开了，但他还是不忍撇下大地孩子置之不理，而是尽力将他仅有的丝丝缕缕余热毫无保留地奉献给他们。叶子在冬姑娘的讥笑中难过地脱下心爱的绿装，换上褶皱的黄褂子；小草在冬姑娘的羞辱之下含泪扔掉穿了一年的舞裙，只剩下枯瘦的躯干。他们不再欢舞了，只瑟瑟地颤抖着。校园中的几棵梧桐树上只有黄叶摇曳在枝头，无情的冬姑娘扯下它们美丽的衣裳，它们只好枯秃地站在那里。在这初冬时节，似乎各种叶子都在挣扎，路上的风萧萧而带着寒意。　　难道所有的草木都屈服在冬姑娘脚下吗？不！你看，那根根青竹，挺直了腰杆，准备接受严冬的洗礼；那株株松柏并非一蹶不振，它们无所畏惧地屹立着，连冬姑娘也无可奈何地溜走了。再看那些棕榈树，它们依然青翠如故，并且都披上蓑衣，犹如勇猛的战士已穿上铠甲，拿起武器严阵以待，准备与寒冬来一次较量。　　初冬又是可爱秀美的。冬姑娘唤醒梦中的腊梅花，它们伸了伸懒腰，迎着寒风，绽放纤柔芳香的花朵，展开微笑的脸庞。枫树的枝头间尚有最后一批红叶，隐在松柏之中，片片青绿，更有点点红褐色点缀其间。青绿与红褐，这对并不和谐的色调，描绘出一幅绚丽多姿、别具一格的初冬的画卷。这幅独一无二的画卷，本身就是初冬的一首最贴切、最完善的赞美诗。　　初冬就似一个冰清玉洁的女孩，超凡脱俗；她又似一个刁蛮成性的小丫头，是那么任性、无理。她虽然如此不可捉摸，但还是惹人喜爱，人们在一年四季中，也不愿缺少她的存在。1．给下列画线字注音。有恃无恐（）　丝丝缕缕（）　褶皱（）　摇曳（）2．写出下列词语的近义词。驱逐——（）　奉献——（）　讥笑——（）　摇曳——（）3．根据解释，写出文中出现的成语。①因为有依仗就无所顾忌。（）②另有一种独特的风格。（）③形容人的品质高尚纯洁。（）4．文章采用了哪些修辞方法？_________________________5．文章第一段主要围绕着初冬的（）特点展开的。

  [ ]

  A．蛮不讲理B．树木开始枯萎C．冬的残酷6．初冬的可爱秀美之处在哪里？文章写了哪些景物？_________________________

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