1、雅思（阅读）历年真题试卷汇编 14 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.Health in the WildMany animals seem able to treat their illnesses themselves. Humans may have a thing or two to learn from them.For the past decade Dr Engel, a l
2、ecturer in environmental sciences at Britains Open University, has been collating examples of self-medicating behaviour in wild animals. She recently published a book on the subject. In a talk at the Edinburgh Science Festival earlier this month, she explained that the idea that animals can treat th
3、emselves has been regarded with some scepticism by her colleagues in the past. But a growing number of animal behaviourists now think that wild animals can and do deal with their own medical needs.One example of self-medication was discovered in 1987. Michael Huffman and Moham-edi Seifu, working in
4、the Mahale Mountains National Park in Tanzania, noticed that local chimpanzees suffering from intestinal worms would dose themselves with the pith of a plant called Veronia. This plant produces poisonous chemicals called terpenes. Its pith contains a strong enough concentration to kill gut parasites
5、, but not so strong as to kill chimps(nor people, for that matter; locals use the pith for the same purpose). Given that the plant is known locally as “goat-killer“, however, it seems that not all animals are as smart as chimps and humans. Some consume it indiscriminately, and succumb.Since the Vero
6、nia-eating chimps were discovered, more evidence has emerged suggesting that animals often eat things for medical rather than nutritional reasons. Many species, for example, consume dirta behaviour known as geophagy. Historically, the preferred explanation was that soil supplies minerals such as sal
7、t. But geophagy occurs in areas where the earth is not a useful source of minerals, and also in places where minerals can be more easily obtained from certain plants that are known to be rich in them. Clearly, the animals must be getting something else out of eating earth.The current belief is that
8、soiland particularly the clay in ithelps to detoxify the defensive poisons that some plants produce in an attempt to prevent themselves from being eaten. Evidence for the detoxifying nature of clay came in 1999, from an experiment carried out on macaws by James Gilardi and his colleagues at the Univ
9、ersity of California, Davis. Macaws eat seeds containing alkaloids, a group of chemicals that has some notoriously toxic members, such as strychnine. In the wild, the birds are frequently seen perched on eroding riverbanks eating clay. Dr Gilardi fed one group of macaws a mixture of a harmless alkal
10、oid and clay, and a second group just the alkaloid. Several hours later, the macaws that had eaten the clay had 60% less alkaloid in their bloodstreams than those that had not, suggesting that the hypothesis is correct.Other observations also support the idea that clay is detoxifying. Towards the tr
11、opics the amount of toxic compounds in plants increasesand so does the amount of earth eaten by herbivores. Elephants lick clay from mud holes all year round, except in September when they are bingeing on fruit which, because it has evolved to be eaten, is not toxic. And the addition of clay to the
12、diets of domestic cattle increases the amount of nutrients that they can absorb from their food by 10-20%.A third instance of animal self-medication is the use of mechanical scours to get rid of gut parasites. In 1972 Richard Wrangham, a researcher at the Gombe Stream Reserve in Tanzania, noticed th
13、at chimpanzees were eating the leaves of a tree called Aspilia. The chimps chose the leaves carefully by testing them in their mouths. Having chosen a leaf, a chimp would fold it into a fan and swallow it. Some of the chimps were noticed wrinkling their noses as they swallowed these leaves, suggesti
14、ng the experience was unpleasant. Later, undigested leaves were found on the forest floor.Dr Wrangham rightly guessed that the leaves had a medicinal purposethis was, indeed, one of the earliest interpretations of a behaviour pattern as self-medication. However, he guessed wrong about what the mecha
15、nism was. His(and everybody elses)assumption was that Aspilia contained a drug, and this sparked more than two decades of phytochemical research to try to find out what chemical the chimps were after. But by the 1990s, chimps across Africa had been seen swallowing the leaves of 19 different species
16、that seemed to have few suitable chemicals in common. The drug hypothesis was looking more and more dubious.It was Dr Huffman who got to the bottom of the problem. He did so by watching what came out of the chimps, rather than concentrating on what went in. He found that the egested leaves were full
17、 of intestinal worms. The factor common to all 19 species of leaves swallowed by the chimps was that they were covered with microscopic hooks. These caught the worms and dragged them from their lodgings.Following that observation, Dr Engel is now particularly excited about how knowledge of the way t
18、hat animals look after themselves could be used to improve the health of livestock. People might also be able to learn a thing or twoand may, indeed, already have done so. Geophagy, for example, is a common behaviour in many parts of the world. The medical stalls in African markets frequently sell t
19、ablets made of different sorts of clays, appropriate to different medical conditions.Africans brought to the Americas as slaves continued this tradition, which gave their owners one more excuse to affect to despise them. Yet, as Dr Engel points out, Rwandan mountain gorillas eat a type of clay rathe
20、r similar to kaolinitethe main ingredient of many patent medicines sold over the counter in the West for digestive complaints. Dirt can sometimes be good for you, and to be “as sick as a parrot“ may, after all, be a state to be desired.Questions 1-4Do the following statements agree with the informat
21、ion given in Reading Passage 1? In boxes 1-4 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).Dr Engel has been working on animal self-medication research for 10 year
22、s.（分数：2.00）A.真B.假C.Not Given(2).Animals often walk a considerable distance to find plants for medication.（分数：2.00）A.真B.假C.Not Given(3).Birds, like Macaw, often eat clay because it is part of their natural diet.（分数：2.00）A.真B.假C.Not Given(4).According to Dr Engel, research into animal self-medication
23、can help to invent new painkillers for livestock.（分数：2.00）A.真B.假C.Not GivenComplete the notes below using NO MORE THAN ONE WORD from the passage.Write your answers in boxes 5-9 on your answer sheet. （分数：10.00）填空项 1:_填空项 1:_填空项 1:_填空项 1:_填空项 1:_Complete the summary below using words from the box. Wri
24、te your answers, A-H, in boxes 10-13 on your answer sheet.Though often doubted, the self-medicating behaviour of animals has been supported by an increasing amount of evidence. One piece of evidence particularly deals with 1, a soil-consuming behaviour commonly found across animals species, because
25、earth, often clay, can neutralize the 2content of their diet.Such behaviour can also be found among humans in Africa, where people purchase 3at market stalls as a kind of medication to their illnesses. Another example of this is found in chimps eating leaves of often 4taste but with no apparent medi
26、cinal value until its unique structure came into light.A mineral B plants C unpleasant D toxicE clay tablets F nutritional G geophagy H harmless（分数：8.00）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.The Conquest of Malaria
27、 in Italy, 1900-1962Mal-aria. Bad air. Even the word is Italian, and this horrible disease marked the life of those in the peninsula for thousands of years. Yet by 1962, Italy was officially declared malaria-free, and it has remained so ever since. Frank Snowdens study of this success story takes us
28、 to areas historians have rarely visited before.A Everybody now knows that malaria is carried by mosquitoes. But in the 19th century, most experts believed that the disease was produced by “miasma“ or “poisoning of the air“. Others made a link between swamps, water and malaria, but did not make the
29、further leap towards insects. The consequences of these theories were that little was done to combat the disease before the end of the century. Things became so bad that 11 m Italians(from a total population of 25m)were “permanently at risk“. In malarial zones the life expectancy of land workers was
30、 a terrifying 22.5 years. Those who escaped death were weakened or suffered from splenomegaly a “painful enlargement of the spleen“ and “a lifeless stare“. The economic impact of the disease was immense. Epidemics were blamed on southern Italians, given the widespread belief that malaria was heredit
31、ary. In the 1880s, such theories began to collapse as the dreaded mosquito was identified as the real culprit.B Italian scientists, drawing on the pioneering work of French doctor Alphonse Laveran, were able to predict the cycles of fever but it was in Rome that further key discoveries were made. Gi
32、ovanni Battista Grassi. a naturalist, found that a particular type of mosquito was the carrier of malaria. By experimenting on healthy volunteers(mosquitoes were released into rooms where they drank the blood of the human guinea pigs), Grassi was able to make the direct link between the insects(all
33、females of a certain kind)and the disease. Soon, doctors and scientists made another startling discovery: the mosquitoes themselves were also infected and not mere carriers. Every year, during the mosquito season, malarial blood was moved around the population by the insects. Definitive proof of the
34、se new theories was obtained after an extraordinary series of experiments in Italy, where healthy people were introduced into malarial zones but kept free of mosquito bites and remained well. The new Italian state had the necessary information to tackle the disease.C A complicated approach was adopt
35、ed, which made use of quinine - a drug obtained from tree bark which had long been used to combat fever, but was now seen as a crucial part of the war on malaria. Italy introduced a quinine law and a quinine tax in 1904, and the drug was administered to large numbers of rural workers. Despite its of
36、ten terrible side-effects(the headaches produced were known as the “quinine-buzz“)the drug was successful in limiting the spread of the disease, and in breaking cycles of infection. In addition, Italy set up rural health centres and invested heavily in education programmes. Malaria, as Snowden shows
37、, was not just a medical problem, but a social and regional issue, and could only be defeated through multi-layered strategies. Politics was itself transformed by the anti-malarial campaigns. It was originally decided to give quinine to all those in certain regions even healthy people; peasants were
38、 often suspicious of medicine being forced upon them. Doctors were sometimes met with hostility and refusal, and many were dubbed “poisoners“.D Despite these problems, the strategy was hugely successful. Deaths from malaria fell by some 80% in the first decade of the 20th century and some areas esca
39、ped altogether from the scourge of the disease. War, from 1915-18, delayed the campaign. Funds were diverted to the battlefields and the fight against malaria became a military issue, laying the way for the fascist approach to the problem. Mussolinis policies in the 20s and 30s are subjected to a se
40、rious cross-examination by Snowden. He shows how much of the regimes claims to have “eradicated“ malaria through massive land reclamation, forced population removals and authoritarian clean-ups were pure propaganda. Mass draining was instituted often at a great cost as Mussolini waged war not on the
41、 disease itself, but on the mosquitoes that carried it. The cleansing of Italy was also ethnic, as “carefully selected“ Italians were chosen to inhabit the gleaming new towns of the former marshlands around Rome. The “successes“ under fascism were extremely vulnerable, based as they were on a top-do
42、wn concept of eradication. As war swept through the drained lands in the 40s, the disease returned with a vengeance.E In the most shocking part of the book, Snowden describes passionately, but with the skill of a great historian how the retreating Nazi armies in Italy in 1943-44 deliberately caused
43、a massive malaria epidemic in Lazio. It was “the only known example of biological warfare in 20th-century Europe“. Shamefully, the Italian malaria expert Alberto Missiroli had a role to play in the disaster: he did not distribute quinine, despite being well aware of the epidemic to come. Snowden cla
44、ims that Missiroli was already preparing a new strategy with the support of the US Rockefeller Foundation using a new pesticide, DDT. Missiroli allowed the epidemic to spread, in order to create the ideal conditions for a massive, and lucrative, human experiment. Fifty-five thousand cases of malaria
45、 were recorded in the province of Littoria alone in 1944. It is estimated that more than a third of those in the affected area contracted the disease. Thousands, nobody knows how many, died. With the war over, the US government and the Rockefeller Foundation were free to experiment. DDT was sprayed
46、from the air and 3m Italians had their bodies covered with the chemical. The effects were dramatic, and nobody really cared about the toxic effects of the chemical.F By 1962, malaria was more or less gone from the whole peninsula. The last cases were noted in a poor region of Sicily. One of the fina
47、l victims to die of the disease in Italy was the popular cyclist, Fausto Coppi. He had contracted malaria in Africa in 1960, and the failure of doctors in the north of Italy to spot the disease was a sign of the times. A few decades earlier, they would have immediately noticed the tell-tale signs; i
48、t was later claimed that a small dose of quinine would have saved his life. As there are still more than 1 m deaths every year from malaria worldwide, Snowdens book also has contemporary relevance. This is a disease that affects every level of the societies where it is rampant. It also provides us w
49、ith “a message of hope for a world struggling with the great present-day medical emergency“.Questions 14-18Complete the summary below using NO MORE THAN TWO WORDS from the passage.Write your answers in boxes 14-18 on your answer sheet.Before the link between malaria and 1was established, there were many popular theories circulating among the public, one of which points to 2, the unclean air. The lack of proper trea
