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  3. What’s Killing the Bats First it was bees. Now it is bats. Biologists in America are working hard to discover the cause of t

What’s Killing the Bats First it was bees. Now it is bats. Biologists in America are working hard to discover the cause of t

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问题                                 What’s Killing the Bats
    First it was bees. Now it is bats. Biologists in America are working hard to discover the cause of the mysterious deaths of tens of thousands of bats in the northeastern part of the country. Most of the bats affected are the common little brown bats ( Myotis lucifugus,) but other species, such as the long-eared bat, the small-footed bat, the eastern pipistrelle, and the Indiana bat have also been affected. In some caves, more than 90 percent of the bat populations have died.
    One possibility is disease. A white fungus (真菌) known as fusarium has been found on the noses of both living and dead bats. However, scientists don’t know if the fungus is the primary cause of death, a secondary cause of death, or not a cause at all, but the result of some other conditions.
    Another possible cause is a lack of food. For example, bats typically eat a large number of moths (蛾) , and in some states such as New York, the number of moths has been declining in recent years. If bats can’t eat enough food, they starve to death.
    Still other scientists believe that global warming is to blame. Warmer temperatures in recent years have been waking up hibernating (冬眠) bats earlier than usual. If bats break their hibernation at the wrong time, they might not find their expected food sources. The weather might also turn cold again and weaken or kill the bats.
    Scientists might not agree on the causes of the bat die-off but they do agree on the consequences. Bats are an important predator of mosquitoes:a single brown bat can eat 1,000 or more insects in an hour. They also eat beetles and other insects that damage plant crops. If there aren’t enough bats, damage will be great from the insects they eat. While bats live a long time for their size—the litde brown bat can live for more than 30 years—a female bat has only one baby per year, so bat populations grow slowly. Many bat species in the United States are already protected or endangered.
    How can you help? Do not disturb sleeping or nesting bats. If you discover bats that seem to be sick or that are dead, contact your local Fish& Wildlife Department with the details. However, be careful not to touch the animals.
What is the main idea of this passage?
选项 A、All species of bats in North America are dying.
B、Scientists already know the cause of the deaths of bats.
C、The bat deaths are a serious problem.
D、There are many possible causes of the deaths of bats.
答案C
解析 主旨大意题。文章前四段讲述的都是可能造成蝙蝠死亡的原因,但在第五段回归到了蝙蝠死亡导致的严重结果上——严重损害农作物。而在最后一段讲述的是如何帮助减少蝙蝠死亡。归根究底,作者是在讲述蝙蝠死亡的严重问题。故本题故选C。
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