剑桥雅思阅读7原文难度解析(test3).docx

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1、剑桥雅思阅读7原文难度解析(test3) 为了帮助大家更好地备考雅思阅读，下面我给大家共享剑桥雅思阅读7原文翻译及答案解析(test3)，希望对你们有用。 剑桥雅思阅读7原文(test3) READING PASSAGE 1 You should spend about 20 minutes on Questions 1-13, which are based on Reading Passage 1 below. Ant Intelligence When we think of intelligent members of the animal kingdom, the creatures

2、 that spring immediately to mind are apes and monkeys. But in fact the social lives of some members of the insect kingdom are sufficiently complex to suggest more than a hint of intelligence. Among these, the world of the ant has come in for considerable scrutiny lately, and the idea that ants demon

3、strate sparks of cognition has certainly not been rejected by those involved in these investigations. Ants store food, repel attackers and use chemical signals to contact one another in case of attack. Such chemical communication can be compared to the human use of visual and auditory channels (as i

4、n religious chants, advertising images and jingles, political slogans and martial music) to arouse and propagate moods and attitudes. The biologist Lewis Thomas wrote, Ants are so much like human beings as to be an embarrassment. They farm fungi, raise aphids_as livestock, launch armies to war, use

5、chemical sprays to alarm and confuse enemies, capture slaves, engage in child labour, exchange information ceaselessly. They do everything but watch television. However, in ants there is no cultural transmission everything must be encoded in the genes whereas in humans the opposite is true. Only bas

6、ic instincts are carried in the genes of a newborn baby, other skills being learned from others in the community as the child grows up. It may seem that this cultural continuity gives us a huge advantage over ants. They have never mastered fire nor progressed. Their fungus farming and aphid herding

7、crafts are sophisticated when compared to the agricultural skills of humans five thousand years ago but have been totally overtaken by modern human agribusiness. Or have they? The farming methods of ants are at least sustainable. They do not ruin environments or use enormous amounts of energy. Moreo

8、ver, recent evidence suggests that the crop farming of ants may be more sophisticated and adaptable than was thought. Ants were farmers fifty million years before humans were. Ants cant digest the cellulose in leaves but some fungi can. The ants therefore cultivate these fungi in their nests, bringi

9、ng them leaves to feed on, and then use them as a source of food. Farmer ants secrete antibiotics to control other fungi that might act as weeds, and spread waste to fertilise the crop. It was once thought that the fungus that ants cultivate was a single type that they had propagated, essentially un

10、changed from the distant past. Not so. Ulrich Mueller of Maryland and his colleagues genetically screened 862 different types of fungi taken from ants nests. These turned out to be highly diverse: it seems that ants are continually domesticating new species. Even more impressively, DNA analysis of t

11、he fungi suggests that the ants improve or modify the fungi by regularly swapping and sharing strains with neighbouring ant colonies. Whereas prehistoric man had no exposure to urban lifestyles the forcing house of intelligence the evidence suggests that ants have lived in urban settings for close o

12、n a hundred million years, developing and maintaining underground cities of specialised chambers and tunnels. When we survey Mexico City, Tokyo, Los Angeles, we are amazed at what has been accomplished by humans. Yet Hoelldobler and Wilsons magnificent work for ant lovers, The Ants, describes a supe

13、rcolony of the ant Formica yessensis on the Ishikari Coast of Hokkaido. This megalopolis was reported to be composed of 360 million workers and a million queens living in 4,500 interconnected nests across a territory of 2.7 square kilometres. Such enduring and intricately meshed levels of technical

14、achievement outstrip by far anything achieved by our distant ancestors. We hail as masterpieces the cave paintings in southern France and elsewhere, dating back some 20,000 years. Ant societies existed in something like their present form more than seventy million years ago. Beside this, prehistoric

15、 man looks technologically primitive. Is this then some kind of intelligence, albeit of a different kind? Research conducted at Oxford, Sussex and Zurich Universities has shown that when desert ants return from a foraging trip, they navigate by integrating bearings and distances, which they continuo

16、usly update in their heads. They combine the evidence of visual landmarks with a mental library of local directions, all within a framework which is consulted and updated. So ants can learn too. And in a twelve-year programme of work, Ryabko and Reznikova have found evidence that ants can transmit v

17、ery complex messages. Scouts who had located food in a maze returned to mobilise their foraging teams. They engaged in contact sessions, at the end of which the scout was removed in order to observe what her team might do. Often the foragers proceeded to the exact spot in the maze where the food had

18、 been. Elaborate precautions were taken to prevent the foraging team using odour clues. Discussion now centres on whether the route through the maze is communicated as a left-right sequence of turns or as a compass bearing and distance message. During the course of this exhaustive study, Reznikova h

19、as grown so attached to her laboratory ants that she feels she knows them as individuals even without the paint spots used to mark them. Its no surprise that Edward Wilson, in his essay, In the company of ants, advises readers who ask what to do with the ants in their kitchen to: Watch where you ste

20、p. Be careful of little lives. Questions 1-6 Do the following statements agree with the information given in Reading Passage 1? In boxes 1-6 on your answer sheet, write TRUE if the statement agrees with the information FALSE if the statement contradicts the information NOT GIVEN if there is no infor

21、mation on this 1 Ants use the same channels of communication as humans do. 2 City life is one factor that encourages the development of intelligence. 3 Ants can build large cities more quickly than humans do. 4 Some ants can find their way by making calculations based on distance and position. 5 In

22、one experiment, foraging teams were able to use their sense of smell to find food. 6 The essay, In the company of ants, explores ant communication. Questions 7-13 Complete the summary using the list of words, A-O, below. Write the correct letter, A-O, in boxes 7-13 on your answer sheet. Ants as farm

23、ers Ants have sophisticated methods of farming, including herding livestock and growing crops, which are in many ways similar to those used in human agriculture. The ants cultivate a large number of different species of edible fungi which convert 7.into a form which they can digest. They use their o

24、wn natural 8.as weed-killers and also use unwanted materials as 9. . Genetic analysis shows they constantly upgrade these fungi by developing new species and by 10.species with neighbouring ant colonies. In fact, the farming methods of ants could be said to be more advanced than human agribusiness,

25、since they use 11.methods, they do not affect the 12.and do not waste 13. . A aphids B agricultural C cellulose D exchanging E energy F fertilizers G food H fungi I growing J interbreeding K natural L other speces M secretions N sustainable O environment READING PASSAGE 2 You should spend about 20 m

26、inutes on Questions 14-26, which are based on Reading Passage 2 on the following pages. Questions 14-19 Reading Passage 2 has seven sections, A-G. Choose the correct headings for sections A-F from the list of headings below. Write the correct number, i-x, in boxes 14-19 on your answer sheet. List of

27、 Headings i The results of the research into blood-variants ii Dental evidence iii Greenbergs analysis of the dental and linguistic evidence iv Developments in the methods used to study early population movements v Indian migration from Canada to the U.S.A. vi Further genetic evidence relating to th

28、e three-wave theory vii Long-standing questions about prehistoric migration to America viii Conflicting views of the three-wave theory, based on non-genetic evidence ix Questions about the causes of prehistoric migration to America x How analysis of blood-variants measures the closeness of the relat

29、ionship between different populations 14 Section A 15 Section B 16 Section C 17 Section D 18 Section E 19 Section F Example Answer Section G viii Population movements and genetics A Study of the origins and distribution of human populations used to be based on archaeological and fossil evidence. A n

30、umber of techniques developed since the 1950s, however, have placed the study of these subjects on a sounder and more objective footing. The best information on early population movements is now being obtained from the archaeology of the living body, the clues to be found in genetic material. B Rece

31、nt work on the problem of when people first entered the Americas is an example of the value of these new techniques. North-east Asia and Siberia have long been accepted as the launching ground for the first human colonisers of the New World1. But was there one major wave of migration across the Beri

32、ng Strait into the Americas, or several? And when did this event, or events, take place? In recent years, new clues have come from research into genetics, including the distribution of genetic markers in modern Native Americans2. C An important project, led by the biological anthropologist Robert Wi

33、lliams, focused on the variants (called Gm allotypes) of one particular protein immunoglobin G found in the fluid portion of human blood. All proteins drift, or produce variants, over the generations, and members of an interbreeding human population will share a set of such variants. Thus, by compar

34、ing the Gm allotypes of two different populations (e.g. two Indian tribes), one can establish their genetic distance, which itself can be calibrated to give an indication of the length of time since these populations last interbred. D Williams and his colleagues sampled the blood of over 5,000 Ameri

35、can Indians in western North America during a twenty-year period. They found that their Gm allotypes could be divided into two groups, one of which also corresponded to the genetic typing of Central and South American Indians. Other tests showed that the Inuit (or Eskimo) and Aleut3 formed a third g

36、roup. From this evidence it was deduced that there had been three major waves of migration across the Bering Strait. The first, Paleo-lndian, wave more than 15,000 years ago was ancestral to all Central and South American Indians. The second wave, about 14,000-12,000 years ago, brought Na-Dene hunte

37、rs, ancestors of the Navajo and Apache (who only migrated south from Canada about 600 or 700 years ago). The third wave, perhaps 10,000 or 9,000 years ago, saw the migration from North-east Asia of groups ancestral to the modern Eskimo and Aleut. E How far does other research support these conclusio

38、n? Geneticist Douglas Wallace has studied mitochondrial DNA4 in blood samples from three widely separated Native American groups: Pima-Papago Indians in Arizona, Maya Indians on the Yucatan peninsula, Mexico, and Ticuna Indians in the Upper Amazon region of Brazil. As would have been predicted by Ro

39、bert Williamss work, all three groups appear to be descended from the same ancestral (Paleo-lndian) population. F There are two other kinds of research that have thrown some light on the origins of the Native American population; they involve the study of teeth and of languages. The biological anthr

40、opologist Christy Turner is an expert in the analysis of changing physical characteristics in human teeth. He argues that tooth crowns and roots5 have a high genetic component, minimally affected by environmental and other factors. Studies carried out by Turner of many thousands of New and Old World

41、 specimens, both ancient and modern, suggest that the majority of prehistoric Americans are linked to Northern Asian populations by crown and root traits such as incisor6 shoveling (a scooping out on one or both surfaces of the tooth), single-rooted upper first premolars6 and triple-rooted lower fir

42、st molars6. According to Turner, this ties in with the idea of a single Paleo-lndian migration out of North Asia, which he sets at before 14,000 years ago by calibrating rates of dental micro-evolution. Tooth analyses also suggest that there were two later migrations of Na-Denes and Eskimo-Aleut. G

43、The linguist Joseph Greenberg has, since the 1950s, argued that all Native American languages belong to a single Amerind family, except for Na-Dene and Eskimo-Aleut a view that gives credence to the idea of three main migrations. Greenberg is in a minority among fellow linguists, most of whom favour

44、 the notion of a great many waves of migration to account for the more than 1,000 languages spoken at one time by American Indians. But there is no doubt that the new genetic and dental evidence provides strong backing for Greenbergs view. Dates given for the migrations should nevertheless be treate

45、d with caution, except where supported by hard archaeological evidence. 1 New World: the American continent, as opposed to the so-called Old World of Europe, Asia and Africa 2 modern Native American: an American descended from the groups that were native to America 3 Inuit and Aleut: two of the ethn

46、ic groups native to the northern regions of North America (i.e. northern Canada and Greenland) 4 DNA: the substance in which genetic information is stored 5 crown/root: parts of the tooth 6 incisor/premolar/molar: kinds of teeth Questions 20 and 21 The discussion of Williamss research indicates the

47、periods at which early people are thought to have migrated along certain routes. There are six routes, A-F, marked on map below. Complete the table below. Write the correct letter, A-F, in boxes 20 and 21 on your answer sheet. Route Period (number of years ago) 20. 15,000 or more 21. 600 to 700 Early Population Movement to the Americas