【題目】 Fireflies flash not just for mating (交配), but survival, a new study suggests. Scientists wanted to find out if there’s more to the lightning bug’s signature blinking glow (一閃一閃的亮光) than finding a mate. Some experts had assumed it was a glaring signal to predators (捕食者), like bats, that fireflies taste bad.

To test out whether the glow acted like that, researchers at Boise State University in Idaho put bats and fireflies in front of high-speed cameras. They published their results in Wednesday’s journal Science Advances.

The painstaking experiment required researchers to introduce western bats, which had never seen lightning bugs before, to the insects. Later, they hand-painted firefly bellies black, turning off their night lights but avoiding the holes the insects breathe through. When the bats first saw the unfamiliar lit-up fireflies, they acted excitedly and ate a lot of the bugs, only to get a bad taste in their mouths.“They shake their heads and spit and generally hate their caretakers for giving them such a rude meal,” said study author Jesse Barber, a Boise State biology professor and author of the study. After a few tries, the bats then avoided the glowing fireflies. Despite the popular misconception, bats aren’t blind, a study author noted.

Once the fireflies essentially taught bats that they taste bad, Barber and his colleagues introduced the darkened fireflies. About 40 percent of the painted ones were eaten, while none of the normal fireflies were eaten. Researchers also think the way lightning bugs fly signals what they are. To test that they put fireflies on fishing lines and the bats went after them, despite already knowing that fireflies don’t taste good. The results make sense and are valuable, said Nick Dowdy, a Purdue University researcher in Indiana, who was not involved in the study.

Scientists already knew that fireflies have distinctive flash patterns that tell others who they are and where they are. And some females prefer males that flash at higher rates, according to study co-author Marc Branham of University of Florida. Barber noted that even in their larval (幼蟲) stage, the bugs glow and don’t get eaten. So he theorized that when it comes to evolution, fireflies’ glowing trait (特點) may have developed first as protection from predators and later became a mating signal.

So, Barber said, “Bats may have invented fireflies.”

1The purpose of the researchers’ study is to see________

A.whether fireflies flash to warn their predators away

B.how fireflies react to high-speed cameras

C.how fireflies flash to attract a mate

D.when fireflies make a bright light

2Why did the researchers put fireflies on fishing lines?

A.To hide their flashes.

B.To make them fly faster.

C.To make them more energetic.

D.To change their flying patterns.

3What does Barber mean in the last paragraph?

A.Bats have influenced fireflies’ evolution.

B.Bats and fireflies depend on each other.

C.Bats have similar traits to fireflies.

D.Bats tend to avoid larval fireflies.

【答案】

1A

2D

3A

【解析】

這是一篇科普說明文,介紹了科學家通過實驗研究,得出結(jié)論:螢火蟲這類發(fā)光的蟲子,之所以發(fā)光,不僅僅是為了交配,更多的是為了生存:以發(fā)光的方式告訴捕食者它們并不是很美味。

1細節(jié)理解題。由第一段“Some experts had assumed it was a glaring signal to predators (捕食者), like bats, that fireflies taste bad.”可知,一些專家認為,發(fā)光是一種信號,向捕食者,比如蝙蝠,暗示它們并不是很美味。為了驗證這一觀點,科學家們做了些研究。結(jié)合選項,故選A項。

2推理判斷題。由第四段“Researchers also think the way lightning bugs fly signals what they are. To test that they put fireflies on fishing lines and the bats went after them,”可知,研究者也認為發(fā)光蟲子飛行的方式暗示了它們的身份。為了驗證這個,他們將螢火蟲縛在釣魚線上,后面跟著蝙蝠。由此可以推斷,研究者將螢火蟲縛在魚線上是為了改變它們的飛行方式,迷惑后面的蝙蝠。故選D項。

3詞義猜測題。由倒數(shù)第二段“Barber noted that even in their larval (幼蟲) stage, the bugs glow and dont get eaten. So he theorized that when it comes to evolution, fireflies glowing trait (特點) may have developed first as protection from predators and later became a mating signal.”可知,Barber注意到,即使在幼蟲期,這些蟲子發(fā)光,就不會被吃掉。因此他推測,螢火蟲發(fā)光的特點首先作為對捕食者的防護,后來才發(fā)展成為求偶信號。也就是說捕食者對發(fā)光蟲子的進化有一定影響。結(jié)合上面的理論,他才說“也許是蝙蝠發(fā)明了螢火蟲!

故選A項。

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