Question

【题目】 Bombardier beetles are known for their skillful response to predators (捕食性动物).If they are about to be eaten, the insects spray their predators with boiling-hot chemicals. If they get swallowed anyway, they have plan B: Blast (爆炸) their way out from the inside.

In an experiment, scientists watched as a Japanese stream toad readily swallowed an Asian bombardier beetle. But 44 minutes later, the toad vomited (呕吐) the contents of its stomach. The insect ran away, physically unharmed.

“The vomited beetle was alive and active,” study authors Shinji Sugiura and Takuya Sato of Kobe University in Japan reported in the journal Biology Letters. Why, the researchers wondered, does luck always favor the escape artists? To find out, they needed more of them, and they needed to feed them to more toads. Scientists gathered 15 species of ground beetles, including the bombardier beetle. They also collected Japanese common toads, which are natural bombardier beetle predators, and Japanese stream toads, which do not live in the same place as the insect.

Sugiura and Sato hypothesized (假设) that over years of exposure, the common toad species developed a greater tolerance to the bombardier beetle's poisonous chemicals than the stream toads had. The bombardier beetles were divided into two groups. Some were poked (戳) with special tools, which caused them to release all their poisonous chemical spray. Other beetles were left alone. Then they were fed to the toads.

The toads that swallowed a fully loaded bombardier beetle were in for a surprise. “An explosion was heard inside each toad, which indicates that the bombardier beetle sent up a chemical spray after being swallowed, the authors wrote. The common toads vomited their prey 35 percent of the time. The stream toads vomited their prey 57 percent of the time. That confirmed their hypothesis about the toads' evolutionary adaptation. All 16 of the vomited insects were “alive and active” 20 minutes later. Almost all the beetles that released their defensive chemicals before meeting the toads were “successfully digested”. The test told the researchers that the beetles' boiling chemical spray was indeed their ticket to freedom.

【1】When Bombardier beetles are in danger, they can ______.

A.have relevant ways to escapeB.bring up the content of stomach

C.cause damage to their enemiesD.make no response to outside attack

【2】What was the scientists’ assumption before the experiment?

A.Bombardier beetles were always lucky to escape.

B.Japanese common toads were natural predators.

C.Common toads had the ability to resist the poison.

D.Bombardier beetles could release poison constantly.

【3】What do we know about Sugiura and Sato’s test?

A.It showed the process of the insects’ evolution.

B.It demonstrated the harm of explosion in the toads.

C.It stressed the importance of a balanced ecosystem.

D.It provided convincing evidence for their assumption.

Answer 1

【答案】

【1】A

【2】C

【3】D

【解析】

这是一篇说明文。文章介绍了一种叫Bombardier beetles的昆虫在被攻击时喷出滚烫的毒液来进行自保。科学家们用日本的常见蟾蜍和溪流蟾蜍两种不同物种来进行试验，发现生活在Bombardier beetles所在地区的常见蟾蜍对那种昆虫喷出来的毒液有抵抗性，而生活在其他的地区的溪流蟾蜍则基本没有这种抵抗力。

【1】

细节理解题。根据文章第一段Bombardier beetles are known for their skillful response to predators. If they are about to be eaten, the insects spray their predators with boiling-hot chemicals. If they get swallowed anyway, they have plan B: Blast (爆炸) their way out from the inside.(庞巴迪甲虫以其对捕食者的熟练反应而闻名。如果它们即将被吃掉，昆虫就会用滚烫的化学物质喷洒捕食者。 如果他们被吞下去，他们有计划B：从内部炸出一条路)可知，无论是喷洒滚烫的化学物质，还是从内部炸出条生路，都是为了从捕食者那里逃脱的方法。故选A。

【2】

细节理解题。根据第四段Sugiura and Sato hypothesized (假设) that over years of exposure, the common toad species developed a greater tolerance to the bombardier beetle's poisonous chemicals than the stream toads had.(杉浦和佐藤假设，在多年的暴露中，普通蟾蜍物种对庞巴迪甲虫有毒化学物质的耐受性比溪流蟾蜍强)可知，在实验之前，科学家假设普通蟾蜍对毒液有抵抗能力。故选C。

【3】

细节理解题。根据最后一段第四行That confirmed their hypothesis about the toads’ evolutionary adaptation.(这证实了他们关于蟾蜍进化适应的假设) 可知，实验为他们的假设提供了令人信服的证据。故选D。