Whendifferentspeciesofbirdsflo

更新 2022-09-03
科目英语
题型阅读理解
难度中等
浏览 1954

When different species of birds flock (聚集) together, their flight formations are determined by social dynamics both between and within species.
New research from the Universities of Cambridge and Exeter reveals for the first time that, contrary to current models used to explain the movement of flocks, the differences between bird species and social relationships between individuals play a critical role in determining the dynamics of mixed-species flocks.
The unified(群集) behaviour of bird flocks has puzzled scientists for hundreds of years. One naturalist from the turn of the century even suggested telepathy(心灵感应)may be involved. There have since been more logical explanations, including mathematical models that show that repeated interactions among individuals following simple rules can generate coordinated (协同的)group movements. However, these models usually rely on the assumption that individuals within groups are identical and interact independently, which may not reflect reality.
Jolle Jolles, a PhD student at the University of Cambridge's Department of Zoology and author of the paper, said：“Spectacular collective behaviour can be found in a large range of animal species, and we now know that often these complex coordinated group movements may be the result of individuals following simple rules. However, rarely are the individual characteristics and social relationships within them taken into account. Our research highlights that these striking displays of group behaviour are much more complex.”
By analysing high-resolution photographs of mixed flocks of rooks and jackdaws (both from the corvid family), the researchers found that rather than individuals interacting in a consistent fashion throughout the flock, interactions depended on social dynamics between the different species as well as relationships within a species.
The researchers discovered that birds prefer to fly close to members of their own species, and that the larger and more dominant rooks take the lead by flying near the front of flocks. Additionally, the lifelong, monogamous(一妻一夫制的)pair bonds that are characteristic of both species seem to be reflected in flight, as birds often fly particularly close to a single, same-species partner.
Dr Alex Thornton, principal investigator of the Cambridge Jackdaw Project, now at the University of Exeter and author of the paper, said: “Together, our findings demonstrate that to understand the structure of groups — such as bird flocks — we need to consider the characteristics and relationships of the individuals within them.”
The underlined word “generate” means ______.

A．set down	B．take away
C．bring about	D．give up

According to Jolle Jolles, what are seldom considered about coordinated group movement?

A．Individual characteristics and social relationship between them

B．Repeated interactions among individuals and social dynamics

C．Telepathy and social relationship between them

D．The structure of groups and the varieties of species

Birds may prefer to fly the closest to _____ .

A．the largest one	B．the most dynamic one
C．the lifelong partner	D．the friendly partner

What is the main idea of the passage?

A．How birds interact in simple rules.

B．How birds of different feathers flock together.

C．Why birds show preference to flocking.

D．Why birds display the characteristics.

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Believe it or not, optical illusion(视觉错觉)can cut highway accidents.
Japan is a case in point. It has reduced traffic accidents on some roads by nearly 75 percent using a simple optical illusion. Bent(弯曲的) stripes, called chevrons(人字形),painted on the roads make drivers think that they are driving faster than they really are, and thus drivers slow down.
Now the American Automobile Association Foundation for Traffic Safety in Washington D.C. is planning to repeat Japan’s success. Starting next year, the Foundation will paint chevrons and other patterns(样式) of stripes on certain roads around the country to test how well the patterns reduce highway accidents.
Overspeeding plays a major role in as much as one fifth of all fatal(致命的) traffic accidents, according to the Foundation. To help reduce those accidents, the Foundation will conduct its tests in areas where speed-related dangers are the greatest-curves, exit slopes, traffic circles, and bridges.
Some studies suggest that straight(直的), horizontal(平行的)bars painted across roads can initially cut the average speed of drivers in half. However, traffic often returns to full speed within months as drivers become used to seeing the painted bars.
Chevrons, scientists say, not only give drivers the impression that they are driving faster than they really are but also make a lane(车道) appear to be narrower(狭窄的). The result is a longer lasting reducing in highway speed and the number of traffic accidents.
1. The passage mainly discusses_____.
A. a new way of highway speed control    B. a new method of training drivers
C. a new pattern for painting highways    D. a new type of optical illusion
2. On roads painted with chevrons, drivers are likely to feel that _________ .
A. they should avoid speed-related dangers
B. they are driving in the wrong lane
C. they should slow down their speed
D. they are reaching the speed limit
3. Compared to horizontal bars, the advantage of chevrons is that _____     .
A. it can keep drivers awake
B. it will have a longer effect on drivers
C. it can cut road accidents in half
D. it will look more attractive
4. The American Automobile Association Foundation for Traffic Safety plans to     .
A. try out the Japanese method in certain areas
B. change the road signs across the country
C. replace straight, horizontal bars with chevrons
D. repeat the Japanese road patterns
5. What does the writer say about straight, horizontal bars painted across roads?
A. The are falling out of use in the United States
B. They are likely to be taken no notice of by drivers in a short time
C. They are suitable only on broad roads.
D. They cannot have a successful effect in traffic circles

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Most of the flowers in nature are red, orange and yellow. If we have seen a black flower, it’s a chance in a million.
People have made a census (普查) to colors of mor e than four thousand kinds of flowers and discovered that only eight of them are black.
As we know, sunlight is formed by seven different colored lights.The wave length of each light is different, so the quantity of heat in each light is also different. Flowers, especially their petals, are easy to be harmed by light temperature.
Black flowers can take in all the light waves which cause the flowers to dry up in the high temperature. So black flowers can rarely survive sunlight. But red flowers, yellow flowers and orange flowers can protect themselves from sunlight by reflecting the red light, yellow light and orange light, each of which has a large quantity of heat.
1. It is _____ to see a black flower.
A. impossible B. seldom C. common D. no chance
2. From the passage we know that _______.
A. black flowers are so weak that it is difficult for them to grow up.
B. there are only eight black flowers in nature
C. sunlight is formed by seven different colored lights, so the wave length of each light is different
D. black flowers can take in the light of all the wave length which makes them dry up because of high temperature
3. Which of the following ideas is WRONG?
A. People have found that only a few kinds of flowers are black.
B. Flowers are easy to be harmed by very high temperature.
C. Red, orange and yellow flowers can also take in the light of all wave lengths.
D. The black flowers can’t protect themselves from sunlight.

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The two largest islands of the British Isles are Great Britain and Ireland. England, Wales and Scotland together form Great Britain. Scotland, lying in the northern part of Great Britain and bordering(接壤)England on the south, is half the size of England and Wales, having an area of about 76 000 square kilometers. Most of Northern Scotland is mountainous area known as the Scottish Highlands. In the center of Scotland there are the Central Low-lands, and the south is waving, hilly area known as the Southern Uplands which rise to 800m. There are many rivers in Great Britain, but they are not very long. The rivers which run to the east are longer than the ones which run to the west.
In Scotland the main rainy winds come from the Atlantic Ocean. The west part is wet with an average(平均) rainfall of up to 200cm while the east is dry with about 75cm. The winters are cold with an average January temperature of 4℃. The summers are cold and warm but rarely hot.
1. This passage mainly tells us____ .
A. how many parts form Great Britain
B. the positions of England, Wales and Scotland
C. the areas of Great Britain
D. Something about Scotland
2. England lies____ .
A. in the south of Great Britain          B. to the south of Scotland
C. to the north of Wales                D. in the north of Scotland
3. This passage also tells us____ .
A. the population of Great Britain        B. the history of England and Wales
C. the size of Scotland                 D. the position of Northern Ireland
4. The Central lowlands_____ .
A. lie between the Scottish Highlands and the Southern Uplands
B. lie to the north of Scottish Highlands
C. lie to the south of the Southern Uplands
D. border England on the south
5. The writer says that in Scotland there is more rain____ .
A. in the Highlands than in the Southern Uplands     B. in the west part than in the east
C. in the Central Lowlands than in the Highland      D. in the east than in the west

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第三部分：阅读理解：（共20小题，每小题2分，满分40分）
阅读下面短文，从每题所给的A、B、C、D四个选项中，选出最佳选项。

Cook wanted for Busy London Restaurant
Experience (经历) required (需要).
Call Tom 020 0451 87.

Dance teacher
We are looking for a dance and singing teacher to teach 4 to 7-year-old children. You only work three hours on Saturdays. You should have teaching experience. Send a CV (求职信) to Steve Reed, 9 Lenton Close, London or telephone 020 8334 47.

Babysitter（保姆）needed
Friendly family needs someone to look after 2 small children.
Some light housework.
Good pay.
Live in our house.
Tel: Mrs. Smith 020 0562 78

Waiters required
Have restaurant knowledge and some bar experience. You will need to love learning new things.
Tel: Cathy 020 4563 12

1. Which job needs you to be able to sing?
A. Babysitter.         B. Dance teacher.       C. Cook.          D. Waiter.
2. What kind of job can Jack do if he cooked in a restaurant from 1998 to 2004?
A. Babysitter.        B. Waiter.           C. Cook.          D. Dance teacher.
3. John has just come to London from another city. She needs a place to live in.
So she may call________________.
A. 020 0451 87      B. 020 4563 12         C. 020 0562 78     D. 020 8334 47

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Liu Xiang, a 21-year-old Chinese athlete, got the gold medal of the fascinating men’s 110m hurdles before a crowd of 70,000 at the Olympic Stadium in the 28th Olympics in Athens late Friday local time. He clocked an excellent 12.91 seconds to equal the world record set by Britain’s Collin Jackson in 1993.
It is the first gold Chinese men’s athlete has ever won from the track and field in the Olympics history. China has won over 100 gold medals from the summer Olympic Games since 1984 but its male athletes only got one medal from Olympics’ most popular sport, the track and field.
The Shanghai native, with his father a truck driver and mother an out-of-work housewife, loved sports when he was very little. Liu was selected to the Junior Sports School of Putuo District of Shanghai to practice jumping as a fourth grader in the primary school. But after a bone test showing that he will not be able to become a tall man, Liu was asked to give up sports one year later, although he had won the national champion at that level.
In 1998 when he attracted coach Sun Haiping’s attention as a 15-year-old jumper, Sun was a well-known hurdle coach and he believed a star was born at the first sight of Liu. He visited Liu’s parents several times and finally persuaded them to let Liu transfer to the 110m hurdles.
After only three years, Liu launched his career in style in the IAAF Grand Prix in Lausanne in 2001 by breaking the world youth and Asian record with a time of 13.12.
But the first warning he sent to the world was his bronze-winning feat（战绩）at the world indoor championships in Birmingham, England, last year.
In 2004, Liu won the silver in the world indoor championships in Budapest in March. Two months later, he proved the winner in a race against American great Allen Johnson in the IAAF Grand Prix in Osaka, Japan, where he clocked a new Asian record and world’s season best time of 13.06 seconds.
He went on to win two Johnson-absent races in Lille, France, on June 26 and Zagreb, Croatia, three days later. He put up an exciting show at the Golden Gala meet in Rome on July 3, when he and Johnson clocked an identical time of 13.11. Race officials had to examine a photo finish to declare Johnson the winner. Liu did a better job of clearing the hurdles than Johnson, but Johnson’s stronger start ended up making the difference. The race boosted（提高） Liu’s optimism(乐观) for the Olympics, although Johnson bettered his season best time by 0.01 second in Lausanne, Switzerland, on July 6.
The world has put the Olympics a Johnson-Liu duel but surprisingly Johnson crashed out of the Games after falling at the ninth hurdle at round 2. Johnson’s early exit paved the way for Liu’s win. He finally took the gold medal and put a Chinese man’s name on the record book.
(chinadaily.com.cn /Xinhua) Updated:2004-08-28 02:57
1. According to Paragraph One, which of the following is TRUE?
A. Liu Xiang is the fastest of the mentioned athletes.
B. Liu Xiang has set a new world record in the event of the men’s 110m hurdles.
C. Both Liu Xiang and Jackson got a gold medal at the Athens Olympics.
D. In the Olympics history, Liu Xiang is the fastest in this event.
2. Before the 28th Olympics in Athens,         .
A. no Chinese athlete got a gold medal from the track and field at the Olympics
B. there was already a Chinese male medal winner in the track and field at the Olympics
C. Terrence Trammell got a gold medal from the men’s hurdles at the Sydney Olympics
D. Zhu Jianhua got a bronze medal from the men’s hurdles in the 1984 Los Angeles Games
3. In the last paragraph, the underlined word “duel” most probably means “       ”.
A. competition       B. friendship   C. partner       D. company
4. From the passage, we can conclude that          .
A. Liu Xiang had no gift for jumping when he was a little boy
B. Liu Xiang set a new world youth record when he was 17 years old
C. Liu Xiang has succeeded because of his coach Sun
D. Johnson might have won the gold medal if he had not dropped out

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