题型：阅读理解 题类：常考题 难易度：普通
宁夏育才中学2018届高三上学期英语期末考试试卷
Bees and other pollinators（传粉者） use smells to track down fresh flowers. Air pollutants can weaken those scents（气味）. Scientists had worried this might make it harder for some pollinators to find a meal.
Many animals help pollinate plants. Species that do this include bees, butterflies, etc. But for many reasons, the pollinators available to help plants in this way are decreasing. Scientists think a loss of habitat（栖息地）can be one factor. Diseases and exposure to poisonous chemicals also count.
Jose Fuentes points to air pollution as another possible factor. He's an atmospheric scientist at Pennsylvania State University. In an earlier study, he showed some air pollutants could weaken or destroy scents emitted(发出)by flowers.
Searching for a meal leaves pollinators out in the open and at risk of becoming other animal's lunch. And any time spent hunting food is time away from their duties back home, like protecting a hive（蜂巢）or nest, explains T'ai Roulston. He's an insect biologist at Virginia University. Roulston worked with Fuentes on the new study.
In the study, the researchers focused on five kinds of representative scent molecules(分子)plants emit. One molecule they looked at, for example, is called beta-myrcene. Many flowers give off this chemical into the air. Normally, this gas can travel some 800 meters from its flower source. But in polluted air, this same molecule could travel only half as far.
Worse still, air pollution might do more than just weaken scent plumes（气味烟云）．Chemical reactions between air pollutants and plumes may transform the flowers' smells, creating new scents. And these scents may be unrecognizable to pollinators.
That's certainly Fuentes' concern. So, he says his next research project will look at how insects handle any new flower scent. "It's possible that some insects will change ways to detect and use these new molecules to find food," he says.
The best books of the year
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Fiction | Simon &Schuster $26. | Asymmetry By Lisa Halliday The first section, "Folly," is the story of a love affair between a book editor and an elderly novelist. The second section, "Madness" describes an Iraqi-American economist who is being held up at Heathrow airport. In "Asymmetry," two seemingly unrelated sections are connected by a shocking finale. |
| Fiction | Viking. $27. | The Great Believers By Rebecca Makkai Set in the Chicago of the mid-80s and Paris at the time of the 2015 terrorist attacks, Makkai's deeply affecting novel uses the AIDS epidemic and a mother's search for her distant daughter to explore the effects of senseless loss and our efforts to overcome it. |
| Nonfiction | Random House $28. | Educated By Tara Westover Westover's extraordinary memoir (回忆录)is an act of courage and self-invention. The youngest of seven children, she grew up in Idaho, in a survivalist family lacking even a birth certificate (证明) and did not attend school until she went to college. The reward for her efforts Is a book that shows to a great thirst to learn. |
| Nonfiction | Simon & Schuster $37.50. | Frederick Douglass By David W. Blight Douglass wrote three autobiographies (自传）himself, describing his rise from slavery to a role as one of the greatest figures of the 19th century, but Blight's work is fuller than any of those, relating both the public and private life in a way that Douglass either could not or would not undertake. |
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