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 (一闪一闪的亮光) 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 (幼虫) stage, the bugs glow and don’t get eaten. So he theorized that when it comes to evolution, fireflies’ glowing trait (特点) may have developed first as protection from predators and later became a mating signal.
So, Barber said, “Bats may have invented fireflies.”
1.The 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
2.Why 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.
3.What 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.
高三英语阅读理解困难题
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 (一闪一闪的亮光) 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 (幼虫) stage, the bugs glow and don’t get eaten. So he theorized that when it comes to evolution, fireflies’ glowing trait (特点) may have developed first as protection from predators and later became a mating signal.
So, Barber said, “Bats may have invented fireflies.”
1.The 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
2.Why 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.
3.What 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.
高三英语阅读理解困难题查看答案及解析
Feathers are not just for flight. They keep birds warm, and attract mates. And for one Australian bird, feathers even help produce an important sound—an alarm.
“People had long noticed these birds produced these loud sounds.” Trevor Murray, a researcher at the Australian National University said. “My supervisor Rob Magrath and May Hingee thought they were used as an alarm. So they did some playbacks and they could show quite strongly that if you play back these sounds to other birds, they flee straightaway. So I was really interested in how they produce the sound, whether it is actually a signal, and whether it’s a reliable signal.”
The team focused their experiment on specific feathers in the pigeon’s wing. “We were able to target the eighth primary feather, which is unusually narrow. And then we also removed, on different sets of birds, those neighboring feathers, the ninth primary feather and the seventh primary feather. And we were able to see when the eighth primary feather was missing, the high note had completely disappeared. So the eighth primary feather produced that high note and the ninth primary feather actually produced the low note.”
And if the birds are fleeing from danger, they produce a louder and higher sound than they do during a normal takeoff. The study is in the journal Current Biology.
Murray and his colleagues did another experiment where they used the recordings they made to observe the reactions of other pigeons. “We were able to see the unusual eighth primary feather was important for signaling the alarm. When that eighth primary feather was missing, they very rarely responded. They almost never fled. Whereas when the ninth primary produces the sound, they fled just as much as to normal alarms. This shows us this unusual primary feather is important for signaling alarm.”
That makes birds of a feather flee together.
1.What does the underlined word “they” in Paragraph 2 refer to?
A. The birds B. Rob and May
C. The feathers D. The loud sounds
2.What did Rob Magrath and May Hingee find out about the birds?
A. They fly away as a group. B. They produce different notes.
C. They send alarms with feathers. D. They attract mates with feathers.
3.Why did the team remove different feathers?
A. To record the notes they produce. B. To keep the pigeons stay in cages
C. To compare their width and length. D. To observe other pigeons’ reactions.
4.According to Murray and his colleagues, why does the unusual feathers matter most?
A. It keeps the pigeons warm B. It responds to alarms
C. It helps birds fly more quickly D. It sounds alarms of danger.
高三英语阅读理解中等难度题查看答案及解析
The world is not only hungry, but it is also thirsty for water．This may seem strange to you，since nearly 70 percent of the earth's surface is covered with water．But about 97 percent of this huge amount is sea water, or salt water．Man can only drink and use the other 3 percent-the fresh water from rivers，lakes，underground，and other sources．And we cannot even use all of that，because some of it is in the form of icebergs and glacier．Even worse，some of it has been polluted．
However，as things stand today, this small amount of fresh water is still enough for us．But our need for water is increasing rapidly-almost day by day．Only if we take steps to deal with this problem now can we avoid a severe worldwide water shortage later on．
We all have to learn how to stop wasting our valuable water．One of the first steps is to develop ways of reusing it．
Today in most large cities，water is used only once and then sent out into a sewer system．From there it returns to the sea or runs into underground storage tanks．But it is possible to pipe used water to a purifying plant．There it can be treated with chemicals so that it can be used again，just as if it were fresh from a spring．
But even if every large city purified and reused its water，we still would not have enough．All we'd have to do make use of the vast reserves of sea water in the world is to remove the salt．
If we take these steps we'll be in no danger of drying up．
1.The world is thirsty for water because we can only use________ percent of the water covering the surface of the earth．
A．3 B．more than 3 C．less than 3 D．97
2.Which of the following statements is NOT TRUE?
A．As things remain unchanging，this small amount of fresh water is still enough for us．
B．Our need for water is becoming larger and larger．
C．There will be no water shortage in the future．
D．We should take steps to deal with the water shortage problem．
3.To reuse water, we should ________．
A．treat it with chemicals B．use it only once
C．send it out into a sewer system D．make it flow into underground tanks
4.In order to have enough water．we should also make use of________．
A．icebergs and glaciers B．sea water
C．rivers and lakes D．underground water
高三英语阅读理解中等难度题查看答案及解析
The world is not only hungry, but it is also thirsty for water．This may seem strange to you，since nearly 70 percent of the earth's surface is covered with water．But about 97 percent of this huge amount is sea water, or salt water．Man can only drink and use the other 3 percent-the fresh water from rivers，lakes，underground，and other sources．And we cannot even use all of that，because some of it is in the form of icebergs and glacier．Even worse，some of it has been polluted．
However，as things stand today, this small amount of fresh water is still enough for us．But our need for water is increasing rapidly-almost day by day．Only if we take steps to deal with this problem now can we avoid a severe worldwide water shortage later on．
We all have to learn how to stop wasting our valuable water．One of the first steps is to develop ways of reusing it．
Today in most large cities，water is used only once and then sent out into a sewer system．From there it returns to the sea or runs into underground storage tanks．But it is possible to pipe used water to a purifying plant．There it can be treated with chemicals so that it can be used again，just as if it were fresh from a spring．
But even if every large city purified and reused its water，we still would not have enough．All we'd have to do make use of the vast reserves of sea water in the world is to remove the salt．
If we take these steps we'll be in no danger of drying up．
56．The world is thirsty for water because we can only use________ percent of the water covering the surface of the earth．
A．3 B．more than 3 C．less than 3 D．97
57．Which of the following statements is NOT TRUE?
A．As things remain unchanging，this small amount of fresh water is still enough for us．
B．Our need for water is becoming larger and larger．
C．There will be no water shortage in the future．
D．We should take steps to deal with the water shortage problem．
58．To reuse water, we should ________．
A．treat it with chemicals B．use it only once
C．send it out into a sewer system D．make it flow into underground tanks
59．In order to have enough water．we should also make use of________．
A．icebergs and glaciers B．sea water
C．rivers and lakes D．underground water
高三英语阅读理解简单题查看答案及解析
As tech gets ever more clever, it opens possibilities - not just for business but for cybercriminals（网络罪犯）.Companies are being kept on their toes to find the most up-to-date security. 1. However, the real question is, "How can we use this securely?"
AIs may make it easier to attack company systems. They also give security experts new ways to detect problems and free them up from repetitive（重复的）work. 2.
AIs also provide new solutions for security operation centers. 3. This job used to be done by skilled analysts（分析师）. But machine learning can now spot 80 percent of false positives, leaving the analysts to work on the potentially harmful 20 percent.
AIs are very good at recognizing new things which are potentially a problem.4.They spot new threats because they've learned what looks normal and what doesn't. You have to accept you will be attacked and deal with it like an immune system would. The next step is to allow Al systems to take action in real time, so you have self-defending networks.5.
A.So they can focus their efforts where they are needed most.
B.This includes old and new tech working side by side.
C.They're a bit like the human immune system.
D.For example, it is very good at identifying misleading security alarms.
E.It's vital to have a right view of how technology is actually used.
F.Then you will have an Al reacting to attacks and you'll never even know it.
G.When they adopt new technology, they often ask themselves, "Is this secure?"
高三英语七选五简单题查看答案及解析
Super Bowl Weekend has just ended, and I was very excited for the big game. But I’m not just a fan of the game: I’m a 13-year-old and offensive guard. I just finished playing my eighth and final season.
During the last two years, they’ve created Title IX regulations that forbid girls from playing contact sports due to safely and “touching” concerns. They claim to be acting in the best interests of young people.
During the 2015 season, the Archdiocese(大主教辖区) announced that it would be my last season because of a rule that girls were not permitted to play football in the league. Right away, I knew I needed to change this rule for not just myself, but for all girls.
So I started a change.org petition(请愿书) that received more than 108,000 signatures!I told my story on national news networks and shows. And in March 2016, the Archbishop changed the rule to make CYO football coed(男女混合的) in Philadelphia.
But in July 2016, the bishops(主教) changed their decision and made football once again for boys only. They let me in for my eighth-grade season, but shut down the opportunity of any other girl to play. I could have walked away, but I knew that I had to stay and fight this rule again for girls who want to play football. I started another petition. No girl should be banned from a game she loves.
I hope that you join me in my effort to call on the bishops of Pennsylvania to permit young people like me to learn and grow together, not separately. You can sign my petition at change.org/girl in football.
1.Why did the author decide to start the first change.org petition?
A. Because she finished her final season.
B. Because she watched Super Bowl Weekend.
C. Because she was banned from the league in 2016.
D. Because she learned a lot about Title IX regulations.
2.What can we learn about the author?
A. She is smart. B. She is selfless.
C. She is generous. D. She is offensive.
3.What is the real purpose of writing the text?
A. To complain the policy is unfair.
B. To express her passion for football.
C. To introduce her change.org petition.
D. To appeal to people to join her in the fight.
4.Where can others sign their names?
A. On the website. B. In the league.
C. On the papers. D. In the letters.
高三英语阅读理解困难题查看答案及解析
A great deal of hotel business comes from people travelling not just for holidays but by people travelling ________ their business activities．
A．in harmony with B．in conflict with
C．by order of D．by virtue of
高三英语单项填空中等难度题查看答案及解析
A great deal of hotel business comes from people travelling not just for holidays but by people travelling ________ their business activities．
A． in harmony with B． in conflict with
C． by order of D． by virtue of
高三英语单项填空中等难度题查看答案及解析
A great deal of hotel business comes from people travelling not just for holidays but by people travelling ________ their business activities．
A． in harmony with B． in conflict with
C． by order of D． by virtue of
高三英语单项填空中等难度题查看答案及解析
A great deal of hotel business comes from people travelling not just for holidays but by people travelling ________ their business activities.
A. in harmony with B. in conflict with
C. by order of D. by virtue of
高三英语单项填空中等难度题查看答案及解析