1、雅思（阅读）历年真题试卷汇编 3 及答案解析(总分：80.00，做题时间：90 分钟)You should spend about 20 minutes on Questions 1-13 which are based on Reading Passage 1 below.LEARNING BY EXAMPLESA Learning Theory is rooted in the work of Ivan Pavlov, the famous scientist who discovered and documented the principles governing how animal
2、s(humans included)learn in the 1900s. Two basic kinds of learning or conditioning occur, one of which is famously known as the classical conditioning. Classical conditioning happens when an animal learns to associate a neutral stimulus(signal)with a stimulus that has intrinsic meaning based on how c
3、losely in time the two stimuli are presented. The classic example of classical conditioning is a dogs ability to associate the sound of a bell(something that originally has no meaning to the dog)with the presentation of food(something that has a lot of meaning for the dog)a few moments later. Dogs a
4、re able to learn the association between bell and food, and will salivate immediately after hearing the bell once this connection has been made. Years of learning research have led to the creation of a highly precise learning theory that can be used to understand and predict how and under what circu
5、mstances most any animal will learn, including human beings, and eventually help people figure out how to change their behaviors.B Role models are a popular notion for guiding child development, but in recent years very interesting research has been done on learning by example in other animals. If t
6、he subject of animal learning is taught very much in terms of classical or operant conditioning, it places too much emphasis on how we allow animals to learn and not enough on how they are equipped to learn. To teach a course of mine I have been dipping profitably into a very interesting and accessi
7、ble compilation of papers on social learning in mammals, including chimps and human children, edited by Heyes and Galef(1996).C The research reported in one paper started with a school field trip to Israel to a pine forest where many pine cones were discovered, stripped to the central core. So the i
8、nvestigation started with no weighty theoretical intent, but was directed at finding out what was eating the nutritious pine seeds and how they managed to get them out of the cones. The culprit proved to be the versatile and athletic black rat(Rattus rattus)and the technique was to bite each cone sc
9、ale off at its base, in sequence from base to tip following the spiral growth pattern of the cone.D Urban black rats were found to lack the skill and were unable to learn it even if housed with experienced cone strippers. However, infants of urban mothers cross fostered to stripper mothers acquired
10、the skill, whereas infants of stripper mothers fostered by an urban mother could not. Clearly the skill had to be learned from the mother. Further elegant experiments showed that naive adults could develop the skill if they were provided with cones from which the first complete spiral of scales had
11、been removed; rather like our new photocopier which you can work out how to use once someone has shown you how to switch it on. In the case of rats, the youngsters take cones away from the mother when she is still feeding on them, allowing them to acquire the complete stripping skill.E A good exampl
12、e of adaptive bearing we might conclude, but lets see the economies. This was determined by measuring oxygen uptake of a rat stripping a cone in a metabolic chamber to calculate energetic cost and comparing it with the benefit of the pine seeds measured by calorimeter. The cost proved to be less tha
13、n 10% of the energetic value of the cone. An acceptable profit margin.F A paper in 1996 Animal Behaviour by Bednekoff and Balda provides a different view of the adaptiveness of social learning. It concerns the seed caching behaviour of Clarks nutcracker(Nucifraga columbiana)and the Mexican jay(Aphel
14、ocoma ultramarina). The former is a specialist, caching 30,000 or so seeds in scattered locations that it will recover over the months of winter; the Mexican jay will also cache food but is much less dependent upon this than the nutcracker. The two species also differ in their social structure, the
15、nutcracker being rather solitary while the jay forages in social groups.G The experiment is to discover not just whether a bird can remember where it hid a seed but also if it can remember where it saw another bird hide a seed. The design is slightly comical with a cacher bird wandering about a room
16、 with lots of holes in the floor hiding food in some of the holes, while watched by an observer bird perched in a cage. Two days later cachers and observers are tested for their discovery rate against an estimated random performance. In the role of cacher, not only nutcracker but also the less speci
17、alised jay performed above chance; more surprisingly, however, jay observers were as successful as jay cachers whereas nutcracker observers did no better than chance. It seems that, whereas the nutcracker is highly adapted at remembering where it hid its own seeds, the social living Mexican jay is m
18、ore adept at remembering, and so exploiting, the caches of others.Questions 1-4Reading Passage 1 has seven paragraphs A-G.Which paragraph contains the following information?Write the correct letter A-G in boxes 1-4 on your answer sheet.（分数：8.00）(1).A comparison between rats learning and human learni
19、ng（分数：2.00）填空项 1:_(2).A reference to the earliest study in animal learning（分数：2.00）填空项 1:_(3).The discovery of who stripped the pine cone（分数：2.00）填空项 1:_(4).A description of a cost-effectiveness experiment（分数：2.00）填空项 1:_Do the following statements agree with the information given in Reading Passage
20、 1? In boxes 5-8 on your answer sheet writeTRUE if the statement agrees with the informationFALSE if the statement contradicts the informationNOT GIVEN if there is no information on this（分数：8.00）(1).The field trip to Israel was to investigate how black rats learn to strip pine cones.（分数：2.00）A.真B.假(
21、2).The pine cones were stripped from bottom to top by black rats.（分数：2.00）A.真B.假(3).It can be learned from other relevant experiences to use a photocopier.（分数：2.00）A.真B.假(4).Stripping the pine cones is an instinct of the black rats.（分数：2.00）A.真B.假Complete the summary below using words from the box.W
22、rite your answers in boxes 9-13 on your answer sheet.While the Nutcracker is more able to cache seeds, the Jay relies 1on caching food and is thus less specialized in this ability, but more 2.To study their behavior of caching and finding their caches, an experiment was designed and carried out to t
23、est these two birds for their ability to remember where they hid the seeds.In the experiment, the cacher bird hid seeds in the ground while the other 3. As a result, the Nutcracker and the Mexican Jay showed different performance in the role of 4at finding the seeds the observing 5didnt do as well a
24、s its counterpart.less more solitary social cacher observerremembered watched Jay Nutcracker（分数：10.00）填空项 1:_填空项 1:_填空项 1:_填空项 1:_填空项 1:_You should spend about 20 minutes on Questions 14-26 which are based on Reading Passage 2 below.A New Ice AgeWilliam Curry is a serious, sober climate scientist, n
25、ot an art critic. But he has spent a lot of time perusing Emanuel Gottlieb Leutzes famous painting “George Washington Crossing the Delaware,“ which depicts a boatload of colonial American soldiers making their way to attack English and Hessian troops the day after Christmas in 1776. “Most people thi
26、nk these other guys in the boat are rowing, but they are actually pushing the ice away,“ says Curry, tapping his finger on a reproduction of the painting. Sure enough, the lead oarsman is bashing the frozen river with his boot. “I grew up in Philadelphia. The place in this painting is 30 minutes awa
27、y by car. I can tell you, this kind of thing just doesnt happen anymore.“But it may again soon. And ice-choked scenes, similar to those immortalized by the 16th-century Flemish painter Pieter Brueghel the Elder, may also return to Europe. His works, including the 1565 masterpiece “Hunters in the Sno
28、w,“ make the now-temperate European landscapes look more like Lapland. Such frigid settings were commonplace during a period dating roughly from 1300 to 1850 because much of North America and Europe was in the throes of a little ice age. And now there is mounting evidence that the chill could return
29、. A growing number of scientists believe conditions are ripe for another prolonged cooldown, or small ice age. While no one is predicting a brutal ice sheet like the one that covered the Northern Hemisphere with glaciers about 12,000 years ago, the next cooling trend could drop average temperatures
30、5 degrees Fahrenheit over much of the United States and 10 degrees in the Northeast, northern Europe, and northern Asia.“It could happen in 10 years,“ says Terrence Joyce, who chairs the Woods Hole Physical Oceanography Department. “Once it does, it can take hundreds of years to reverse.“ And he is
31、alarmed that Americans have yet to take the threat seriously.A drop of 5 to 10 degrees entails much more than simply bumping up the thermostat and carrying on. Both economically and ecologically, such quick, persistent chilling could have devastating consequences. A 2002 report titled “Abrupt Climat
32、e Change: Inevitable Surprises,“ produced by the National Academy of Sciences, pegged the cost from agricultural losses alone at $100 billion to $250 billion while also predicting that damage to ecologies could be vast and incalculable. A grim sampler: disappearing forests, increased housing expense
33、s, dwindling freshwater, lower crop yields, and accelerated species extinctions.The reason for such huge effects is simple. A quick climate change wreaks far more disruption than a slow one. People, animals, plants, and the economies that depend on them are like rivers, says the report: “For example
34、, high water in a river will pose few problems until the water runs over the bank, after which levees can be breached and massive flooding can occur. Many biological processes undergo shifts at particular thresholds of temperature and precipitation.“Political changes since the last ice age could mak
35、e survival far more difficult for the worlds poor. During previous cooling periods, whole tribes simply picked up and moved south, but that option doesnt work in the modern, tense world of closed borders. “To the extent that abrupt climate change may cause rapid and extensive changes of fortune for
36、those who live off the land, the inability to migrate may remove one of the major safety nets for distressed people,“ says the report.But first things first. Isnt the earth actually warming? Indeed it is, says Joyce. In his cluttered office, full of soft light from the foggy Cape Cod morning, he exp
37、lains how such warming could actually be the surprising culprit of the next mini-ice age. The paradox is a result of the appearance over the past 30 years in the North Atlantic of huge rivers of freshwaterthe equivalent of a 10-foot-thick layermixed into the salty sea. No one is certain where the fr
38、esh torrents are coming from, but a prime suspect is melting Arctic ice, caused by a buildup of carbon dioxide in the atmosphere that traps solar energy.The freshwater trend is major news in ocean-science circles. Bob Dickson, a British oceanographer who sounded an alarm at a February conference in
39、Honolulu, has termed the drop in salinity and temperature in the Labrador Seaa body of water between northeastern Canada and Greenland that adjoins the Atlantic“arguably the largest full-depth changes observed in the modem instrumental oceanographic record.“The trend could cause a little ice age by
40、subverting the northern penetration of Gulf Stream waters. Normally, the Gulf Stream, laden with heat soaked up in the tropics, meanders up the east coasts of the United States and Canada. As it flows northward, the stream surrenders heat to the air. Because the prevailing North Atlantic winds blow
41、eastward, a lot of the heat wafts to Europe. Thats why many scientists believe winter temperatures on the Continent are as much as 36 degrees Fahrenheit warmer than those in North America at the same latitude. Frigid Boston, for example, lies at almost precisely the same latitude as balmy Rome. And
42、some scientists say the heat also warms Americans and Canadians. “Its a real mistake to think of this solely as a European phenomenon,“ says Joyce.Having given up its heat to the air, the now-cooler water becomes denser and sinks into the North Atlantic by a mile or more in a process oceanographers
43、call thermohaline circulation. This massive column of cascading cold is the main engine powering a deepwater current called the Great Ocean Conveyor that snakes through all the worlds oceans. But as the North Atlantic fills with freshwater, it grows less dense, making the waters carried northward by
44、 the Gulf Stream less able to sink. The new mass of relatively fresh water sits on top of the ocean like a big thermal blanket, threatening the thermohaline circulation. That in turn could make the Gulf Stream slow or veer southward. At some point, the whole system could simply shut down, and do so
45、quickly. “There is increasing evidence that we are getting closer to a transition point, from which we can jump to a new state.“Questions 14-17Choose the correct letter A, B, C orD.Write your answers in boxes 14-17 on your answer sheet.（分数：8.00）(1).The writer uses paintings in the first paragraph to
46、 illustrate（分数：2.00）A.possible future climate change.B.climate change of the last two centuries.C.the river doesnt freeze in winter anymore.D.how George Washington led his troops across the river.(2).Which of the following do scientists believe to be possible?（分数：2.00）A.The temperature may drop over
47、 much of the Northern Hemisphere.B.It will be colder than 12,000 years ago.C.The entire Northern Hemisphere will be covered in ice.D.Europe will look more like Lapland.(3).Why is it difficult for the poor to survive the next ice age?（分数：2.00）A.People dont live in tribes anymore.B.Politics are changi
48、ng too fast today.C.Abrupt climate change causes people to live off their land.D.Migration has become impossible because of closed borders.(4).Why is continental Europe much warmer than North America in winter?（分数：2.00）A.Wind blows most of the heat of tropical current to Europe.B.Europe and North Am
49、erica are at different latitudes.C.The Gulf Stream has stopped yielding heat to the air.D.The Gulf Stream moves north along the east coast of North America.Look at the following statements(Questions 18-22)and the list of people in the box below.Match each statement with the correct person A-D.Write the appropriate letter A-D in boxes 18-22 on your answer sheetNB You many wse any letter more than once.List of PeopleA Willia
