2. 外语
  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

admin2015-06-19  48
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.
The "moths" in Paragraph 3 are taken as an example of______.
选项 A、diseases that kill bats
B、insects that bats eat
C、animals that have diseases
D、bat species that are starving to death
答案D
解析 第三段首句讲蝙蝠死亡的一个可能原因就是缺乏食物,紧接着以纽约蛾的数量近年来一直在下降为例,说明蝙蝠缺少食物。因此蛾是蝙蝠因饥饿而死亡的一个例子。
转载请注明原文地址:https://www.kaotiyun.com/show/0IGd777K
本试题收录于： 职称英语理工类A级题库职称英语分类
0

职称英语理工类A级

职称英语

相关试题推荐
随机试题
最新回复(0)