共用题干What’s Killing the BatsFirst it was bees.Now

共用题干

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 hiberna- lion 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 conse- quences. 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 little 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?

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.