Assassin (暗杀者) bugs live up to their name. The insects expertly hunt and feed upon other small invertebrates (无脊椎动物), giving them a poisonous bite. Some species even hunt spiders and use a strange trick to gain the upper hand.
Using their antennae (触须), assassin bugs tap spiders, which appears to confuse them long enough to let the bugs make a poisonous strike, researchers reported on September 29. The findings provide insight into some of the complex hunting tactics that predators (捕食性动物) evolve when targeting dangerous prey (猎物) .
Assassin bugs spend their lives in a place most insects avoid: spider webs. The bugs silently creep along the spider’s silk, taking care to make their movements seem harmless before violently killing the web’s architect, seizing the spiders with their front legs and injecting them with poison.
While watching two species of assassin bugs hunt spiders, ecologists Anne Wignall and Fernando Soley took note of the bugs’ habit of lightly knocking their antennae on spiders once the bugs were within striking distance.
“It struck us early on that tapping prey was a really strange thing to do,” says Wignall. Spiders could easily defend themselves and kill the bugs. “Watching the bugs spend so much time and effort on avoiding detection, only to practically tap the spiders on the shoulder was absolutely fascinating.”
To figure out why the bugs tap, Wignall and Soley tested the behavior of 30 spiders in the laboratory. The researchers copied the bugs’ antennae tapping by gently brushing the spiders’ leg with a dog hair. After the tapping, the team measured the spiders’ responses to movements on the web, copying a struggling insect.
Tapped spiders were far less aggressive than those that weren’t tapped, fully ignoring the movements four times as often. Tapped spiders also attacked about 25 percent as often as their untapped counterparts.
Wignall thinks that the assassin bugs are reducing spiders’ aggression levels by imitating the types of physical touch that these typically solitary (独处的) spiders experience near fellow spiders. “Whenever they do come across another spider, it’s usually because it’s a close relative in the nest, or a potential mate. Both of which are situations in which aggression would not be a good idea,” she says.
Zoologist Ondřej Michálek, who was not involved with the study, says that the researchers have a “completely valid theory.” Many spiders avoid cannibalism (同类相食) by using special touch signals that could be copied by skilful predators, thus tricking the spiders, he says.
1. What is unusual about assassin bugs?A.Their bite is poisonous. | B.Their movements make little noise. |
C.They don’t avoid spiders’ webs. | D.They kill their prey violently. |
A.They used a great deal of time and effort. | B.They were able to defend themselves. |
C.They deliberately touched the spiders. | D.They were able to kill the spiders. |
A.They are keen on physical touch. | B.They are pretending to be spiders. |
C.They are usually solitary. | D.They are looking for a mate. |
A.Why animals use complex hunting tactics. | B.Why assassin bugs tap their prey. |
C.Assassin bugs have a poisonous bite. | D.Assassin bugs-a dangerous predator. |
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【推荐1】If you have ever had a cat, or have watched one of the many funny cat videos online, you’ll know that cats have a mind of their own. A lot of the things they do are hard to understand—they like to climb up tall furniture, fit themselves in small spaces and attack small objects for no reason at all.
Now scientists have managed to figure out what exactly is going on in the brains of our little friends. According to Tony Buffington, a professor at Ohio State University in the US, cats’ strange behavior largely comes from their way of life back in the wild. “Cats today still have many of the same instincts that allowed them to live in the wild for millions of years.” he said in a TED Talk. “To them, our homes are their jungles.”
In the wild, cats are hunters. Their bodies and great balancing abilities allow them to climb to high spots to better look at the environment. Even though they don’t have to hunt any more in human houses, they still keep the old habit of viewing the living room from, for example, the top of the refrigerator.
Cats’ hunting instinct is also what makes them attack small things like keys and USB drives. In the wild, they hunt whatever they can get, and most of the animals they kill are small.
However, cats can also be prey. This explains why they like to stay in small spaces like drawers or washing machines— they are hiding, or they think they are hiding, from more dangerous animals. This is also why cats prefer a clean box: a smelly one could easily show enemies where they are.
Knowing how cats’ minds work is not only useful for better understanding them. It may also help cats’ owners to better meet cats’ needs. For example, owners could try to make climbing easier for cats by moving their furniture around. They could also use “food puzzles” to make eating feel more like hunting instead of just giving food to the cats.
1. According to Tony Buffington, ________.A.cats’ strange behavior is difficult for humans to understand |
B.cats are more used to living in the wild than in humans’ homes |
C.cats’ instincts are as helpful to them today as they were millions of year ago |
D.cats behave strangely mainly because they still have some instincts in the wild |
A.Cats like to climb up high because they want to hide from dangerous animals. |
B.Cats attack keys and USB drives because they have a habit of hunting small animals. |
C.Cats enjoy staying in small spaces because they usually live in small caves in the wild. |
D.Cats’ preference for a clean litter box has something to do with their hunting habits. |
A.an animal that is hunted |
B.an animal that is too shy |
C.an animal that keeps itself clean |
D.an animal that likes hiding games |
A.describe cats’ past wild experience to readers |
B.explore the reasons for cats’ strange behavior |
C.tell cat owners how to make life easier for cats |
D.compare cats’ behavior in human homes with that in the wild |
【推荐2】You needn’t book an expensive holiday to the lands of Africa to see animals. The UK offers a surprising number of wildlife experiences perfect for a family day out.
ZSL Whipsnade Zoo, Bedfordshire
The UK’s largest zoo makes an excellent day out for all the family. It is home to over 3, 900 animals. The stars of the zoo are the four baby tigers born at the zoo. Kids will be surprised by giraffe-feeding and the chance to watch lions. Little kids will be equally interested in Hullabazoo Farm, where they can play with animals such as little pigs and rabbits. Restaurant choices include River Cottage Kitchen.
Train station: Luton
Cost: Adult, £22. 90; child, £16. 60.
Blair Drummond Safari Park, Stirling
Blair Drummond Safari Park opened to the public in 1970 and is home to over 350 animals. There are animal presentations throughout the day. The education team makes their way around six of the enclosures (围场), giving talks on elephants, giraffes, tigers, penguins, etc. The talks include information about the natural environment and the behaviour of the animals.
Train station: Stirling
Cost: Adult, £16. 25; child, £13. 25.
Chester Zoo, Cheshire
Chester Zoo is the most-visited wildlife attraction in the UK. Covering over 50 hectares (公顷), it has more than 21, 000 animals. You can find animals such as jaguars, sloths, blue-eved cockatoos, Sumatran tigers, etc. There are plenty of picnic areas for lunch, and restaurants include Manado Street Kitchen and The Oakfield.
Train station: Chester
Cost: Adult, £16. 36; child, £13. 18.
1. If Tom, 12, wants to visit the largest zoo in the UK, how much should he pay?A.£13. 18. | B.£ 13. 25. | C.£ 16. 60. | D.£ 22. 90. |
A.well-equipped | B.newly-built | C.romantic | D.educational |
A.It has the largest number of animals. | B.There are restaurants in the zoo. |
C.People can get there by train. | D.It covers the largest area. |
If you look carefully at the plants around you, you will find that there are two kinds of plants: flowering plants and non-flowering plants. Flowering plants can make seeds. The seeds are protected by the fruits. Some fruits have one seed, some have two, three or four, and some have many seeds. But a few fruits have no seeds at all. An example of a fruit without seeds is the banana fruit. Most non-flowering plants do not grow from seeds. They grow from spores(胚芽). Spores are very small. Some spores are so small and light that they can float in the air. We may say that spores are quite the same as seeds. When these spores are all on wet and shady places, they usually grow into new plants.
1. The main idea of the first paragraph is that ________.
A.plants are important for life | B.plants cannot grow without air |
C.there are many plants in the world | D.we can not live without water |
A.Of all living things animals are most. |
B.Spores are seeds. |
C.All fruits of flowering plants have seeds. |
D.Without plants, man will die out. |
A.Kept. | B.Guarded. |
C.Prevented. | D.Surrounded |
A.a medicine book | B.a novel |
C.a science magazine | D.an experiment report |
【推荐1】The common cold is the world’s most widespread illness. People believe that colds are caused by cold. They are not. They are caused by viruses passing on from person to person. You catch a cold, and it would be reasonable to expect the Eskimos to suffer from them forever. But they do not. And in isolated arctic regions explorers have reported being free from colds until coming into contact again with infected people from the outside world by way of packages and mail dropped from airplanes.
During the First World War soldiers who spent long periods in the trenches(战壕), cold and wet, showed no increased tendency to catch colds.
In the Second World Was prisoners at the notorious Auschwitz concentration camp, naked and starving, were astonished to find that they seldom had colds.
At the Common Cold Research Unit England, volunteers took part in experiments in which they gave themselves to the discomforts of being cold and wet for long stretches of time. After taking hot baths, they put on bathing suits, allowed themselves to be dipped with cold water, and them stood about dripping wet in wind. Some wore wet socks all day while others exercised in the rain until close to exhaustion. Not one of the volunteers came down with a cold unless a cold virus was actually dropped in his nose.
In the cold we have nothing to do with catching colds. Why are they more frequent in the winter? Despite the most pains-taking research, no one has yet found the answer. One explanation offered by scientists is that people tend to stay together indoors more in cold weather than at other times, and this makes it easier for cold viruses to be passed on.
No one has yet found a cure for the cold. There are drugs and painkillers such as aspirin, but all they do is to relieve the symptoms(症状).
1. Besides the experiments in England, the writer offered more examples to support his argument.A.3 | B.4 | C.5 | D.6 |
A.The Eskimos do not suffer from colds all the time. |
B.Colds are not caused by cold. |
C.People suffer from colds just because they like to stay indoors. |
D.A person may catch a cold by touching someone who already has one. |
A.they are working in the inolated arctic regions |
B.they are writing reports in terribly cold weather |
C.they are free from work in the isolated arctic regions |
D.they are coming into touch again with the outside world |
A.suffered a lot | B.never caught colds |
C.often caught colds | D.became very strong |
【推荐2】Everyone knows a power nap feels good, but do you know that power naps fit right into your normal sleep or wake cycle? And, if done right, they can really help you get through the day.
We are built to nap
Our bodies have an inside timekeeper called the circadian rhythm. The term “circadian” comes from the Latin words meaning “about (circa) a day (diem)”. It is based on 24-hour light/dark cycle and allows your body to keep with the light/dark environment. The circadian rhythm helps you fall asleep and wake up. It changes during the day, as shown in the picture.
Keys to power napping
Your body’s circadian rhythm falls and rises throughout the day. With the largest fall in the afternoon, your body becomes more tired during this time. That is to say, in the afternoon, you are designed for napping.
In studies, a nap lasting a quarter can do the most help in school performance and thinking ability. It helps you to concentrate on your class and reduce stress without affecting your ability to fall asleep at night. As for when to start, the best answer will be around 2:00 pm according to the variation of circadian rhythm.
In addition to the length and the timing, there are other ways you can make the most of your power naps:
Try deep-breathing or another relaxation technique as you start.
Choose a quiet, darkened location. A sleep mask may help.
Lie down or sit in a comfortable chair.
Listen to soft music or white noise.
Try a bit of stretching and walking around to refresh after your nap.
1. At which time does the circadian rhythm decrease?A.From 7:00 am to 10:00 am. | B.From 10:00 am to 12:00 pm. |
C.From 12:00 pm to 2:00 pm. | D.From 2:00 pm to 10:00 pm. |
A.15 minutes. | B.30 minutes. | C.45 minutes. | D.60 minutes. |
A.Stay in a quiet place. | B.Listen to soft music. |
C.Stretch our bodies. | D.Remove the eye mask. |
The expression was first used in 1913 by a young American called Arthur Momand. He told this story about himself. He began earning $ 125 a week at the age of 23. That was a lot of money in those days. He got married and moved with his wife to a very wealthy neighbourhood outside New York City. When he saw that rich people rode horses, Momand went horseback riding every day. When he saw that rich people had servants, Momand and his wife also hired a servant and gave big parties for their new neighbours.
It was like a race, but one could never finish this race because one was always trying to keep up. The race ended for Momand and his wife when they could no longer pay for their new way of life. They moved back to an apartment in New York City.
Momand looked around him and noticed that many people do things just to keep up with rich life--style of their neighbours. He saw the funny side of it and started to write a series of short stories, He called it ‘Keeping up with the Joneses’ because ‘Jones’ is a very common name in the United States.’ Keeping up with the Joneses’ came to mean keeping up with rich lifestyle of the people around you. Momand’s series appeared in different newspapers across the country for over 28 years.
People never seem to get tired of keeping up with the Joneses. And there are ‘Jonses’ in every city of the world. But one must get tired of trying to keep up with the Joneses because no matter what one does, Mr. Jones always seems to be ahead.
1. Some people want to keep up with the Joneses because they ______.
A.want to be as rich as their neighbours |
B.want others to know or to think that they are rich |
C.don’t want others to know they are rich |
D.want to be happy |
A.live outside New York City | B.live in New York City |
C.live in apartments | D.have many neighbours |
A.a person who lives near another | B.people living in an area |
C.an area near the place referred to | D.an area in another town or city |
A.an important name | B.a popular name in the United States |
C.his neighbour’s name | D.not a good name |
A.correct | B.interesting | C.impossible | D.good |
【推荐1】
Ralph Modjeski (1861—1940) Ralph Modjeski was born in Poland. He moved to the US in 1876. By the early 1890s, he had opened his own bridge-building firm in Chicago. He built suspension and railroad bridges all over the country. His most famous bridge is the San Francisco-Oakland Bay Bridge. He also employed Joseph B Strauss. Strauss later opened his own firm and changed the idea of Bascule bridges. Strauss is most famous for building the Golden Gate Bridge in San Francisco. | John A. Roebling (1806—1869) John A. Roebling moved to the US from Germany in 1830. He invented a way to make wire rope to hold suspension bridges. He built his first railroad suspension bridges from Niagara, New York to Canada. His most famous bridge is New York’s Brooklyn Bridge. He died after an accident during the construction. His son Washington completed the bridge by following his careful plans. |
Conde B. McCullough (1887—1946) Conde B. McCullough grew up in Iowa. His fame took off when he moved to Oregon in 1926. He oversaw the state’s Department of Transportation for 25 years. During that time, he helped build many bridges along Oregon’s newly constructed coastal Highway 101. He combined artistic styles with practical function. He became known for his use of simple but attractive arches. | Othmar Ammann (1861—1965) Othmar Ammann was born in Switzerland. He settled in New York City in 1904. He worked on some of the most famous bridges that keep that city connected. They include the George Washington Bridge, the Triborough Bridge, the Goethals Bridge, and the Verrazzano-Narrows Bridge. Ammann was known for his ability to create bridges that combined beauty with strength. |
A.The Golden Gate Bridge. |
B.The George Washington Bridge. |
C.New York’s Brooklyn Bridge. |
D.The Verrazzano-Narrows Bridge. |
A.Ralph Modjeski. | B.Othmar Ammann. |
C.John A. Roebling. | D.Conde B. MeCullough. |
A.They all set up their firms. | B.They were famous bridge engineers. |
C.They were born in the same place. | D.They were famous in the early 1800s. |
【推荐2】Hundreds of years ago, life was much harder than it is today, people did not have modern machines. There was no modern medicine, either.
Life today has brought new problems. One of the biggest is pollution. Water pollution has made our rivers and lakes dirty. It kills our fish and affects our drinking water. Noise pollution makes us talk louder and become angry more easily. Air pollution is the most serious kind of pollution. It affects every living thing in the world.
Cars, planes and factories all pollute our air every day. Sometimes the pollution is so thick that it is like a quilt(被子) over a city. This kind of quilt is called smog.
Many countries are making new laws to fight pollution. Factories must now clean their water before it is thrown away; they mustn’t blow dirty smoke into the air.
We need to do many other things. We can put waste things in the dustbin and not throw them on the ground. We can go to work by bus or with our friends in the some car. If there are fewer people driving, there will be less pollution.
Laws are not enough. Every person must help to fight pollution.
1. Life was harder hundreds of years ago because _________.A.the weather was bad | B.there were no cities |
C.people had no modern machines | D.people couldn’t make machines |
A.Swimming | B.Polluted water | C.Growing population | D.Warmer weather |
A.they can’t get enough money | B.They are often hungry |
C.there’s much traffic on the roads | D.there’s much noise around them |
A.everyone should do something to fight pollution |
B.all the laws can stop factories going on polluting |
C.few countries can stop the air and water being polluting |
D.people have to live in the polluted air.. |
【推荐3】John Snow was an English physician. His father worked in a coal yard. Snow was the firstborn in the low-income family of nine children. At the age of 14, he had to quit school and get a medical apprenticeship (学徒期).
When visiting coal miners as an apprentice, Snow met with cholera—a disease which later became the focus of his scientific research. Snow began his formal medical education in 1836. In 1837, he began to work at the Westminster Hospital. The following year he was admitted as a member of the Royal College of Surgeons of England. Six years later, he received a Doctor of Medicine degree from the University of London. He was admitted to the Royal College of Physicians in1850.
Snow is famous for two of his studies. The first study concerned the Broad Street pump (水泵) outbreak of 1854. He used graphs and maps to show the impact of the polluted water coming from the Broad Street pump. Snow reasoned that cholera was caused by a germ (细菌) that spread through polluted water, which diverged from the view held by other physicians that cholera was spread by bad air. The second study was the “Grand Experiment”, also of 1854. In1849, he first published his ideas and observations in an essay, On the Mode of Communication of Cholera.
1. What can we know about John Snow from Paragraph 1?A.He was an English physicist. |
B.He came from a poor family. |
C.He was the youngest child in his family. |
D.He used to be an apprentice in a coal yard. |
A.In 1838. | B.In 1843. | C.In 1844. | D.In 1850. |
A.Disagreed. | B.Distanced. | C.Differed. | D.Defended. |
A.John Snow’s great impact. | B.John Snow’s famous essay. |
C.John Snow’s study method. | D.John Snow’s well-known research. |