Tag: Science (IELTS)

Reading Passage 1

Pulling Strings to Build Pyramids

No one knows exactly how the pyramids were built. Marcus Chown reckons the answer could be ‘hanging in the air’.

The pyramids of Egypt were built more than three thousand years ago, and no one knows how. The conventional picture is that tens of thousands of slaves dragged stones on sledges. But there is no evidence to back this up. Now a Californian software consultant called Maureen Clemmons has suggested that kites might have been involved. While perusing a book on the monuments of Egypt, she noticed a hieroglyph that showed a row of men standing in odd postures. They were holding what looked like ropes that led, via some kind of mechanical system, to a giant bird in the sky. She wondered if perhaps the bird was actually a giant kite, and the men were using it to lift a heavy object.

Intrigued, Clemmons contacted Morteza Gharib, aeronautics professor at the California Institute of Technology. He was fascinated by the idea. ‘Coming from Iran, I have a keen interest in Middle Eastern science/ he says. He too was puzzled by the picture that had sparked Clemmons’s interest. The object in the sky apparently had wings far too short and wide for a bird. ‘The possibility certainly existed that it was a kite,’ he says. And since he needed a summer project for his student Emilio Graff, investigating the possibility of using kites as heavy lifters seemed like a good idea.

Gharib and Graff set themselves the task of raising a 4.5-metre stone column from horizontal to vertical, using no source of energy except the wind. Their initial calculations and scale-model wind-tunnel experiments convinced them they wouldn’t need a strong wind to lift the 33.5-tonne column. Even a modest force, if sustained over a long time, would do. The key was to use a pulley system that would magnify the applied force. So they rigged up a tent-shaped scaffold directly above the tip of the horizontal column, with pulleys suspended from the scaffold’s apex. The idea was that as one end of the column rose, the base would roll across the ground on a trolley.

Earlier this year, the team put Clemmons’s unlikely theory to the test, using a 40-square- metre rectangular nylon sail. The kite lifted the column clean off the ground. ‘We were absolutely stunned,’ Gharib says. The instant the sail opened into the wind, a huge force was generated and the column was raised to the vertical in a mere 40 seconds.’

The wind was blowing at a gentle 16 to 20 kilometres an hour, little more than half what they thought would be needed. What they had failed to reckon with was what happened when the kite was opened. There was a huge initial force – five times larger than the steady state force,’ Gharib says. This jerk meant that kites could lift huge weights, Gharib realised. Even a 300-tonne column could have been lifted to the vertical with 40 or so men and four or five sails. So Clemmons was right: the pyramid, builders could have used kites to lift massive stones into place. Whether they actually did is another matter,’ Gharib says.

There are no pictures showing the construction of the pyramids, so there is no way to tell what really happened. The evidence for using kites to move large stones is no better or worse than the evidence for the brute force method,’ Gharib says.

Indeed, the experiments have left many specialists unconvinced. The evidence for kite-lifting is non-existent,’ says Willeke Wendrich, an associate professor of Egyptology at the University of California, Los Angeles. Others feel there is more of a case for the theory. Harnessing the wind would not have been a problem for accomplished sailors like the Egyptians. And they are known to have used wooden pulleys, which could have been made strong enough to bear the weight of massive blocks of stone. In addition, there is some physical evidence that the ancient Egyptians were interested in flight. A wooden artefact found on the step pyramid at Saqqara looks uncannily like a modem glider. Although it dates from several hundred years after the building of the pyramids, its sophistication suggests that the Egyptians might have been developing ideas of flight for a long time. And other ancient civilisations certainly knew about kites; as early as 1250 BC, the Chinese were using them to deliver messages and dump flaming debris on their foes.

The experiments might even have practical uses nowadays. There are plenty of places around the globe where people have no access to heavy machinery, but do know how to deal with wind, sailing and basic mechanical principles. Gharib has already been contacted by a civil engineer in Nicaragua, who wants to put up buildings with adobe roofs supported by concrete arches on a site that heavy equipment can’t reach. His idea is to build the arcnes horizontally, then lift them into place using kites. We’ve given him some design hints,’ says Gharib. We’re just waiting for him to report back.’ So whether they were actually used to build the pyramids or not, it seems that kites may make sensible construction tools in the 21st century AD.

Such enduring and intricately meshed levels of technical 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 man looks technologically primitive. Is this then some kind of intelligence, albeit of a different kind?

Questions 1-7

Do the following statement with the information given in Reading Passage 1?

In boxes 1-7 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 information on this this

1. It is generally believed that large numbers of people were needed to build the pyramids.
2. Clemmons found a strange hieroglyph on the wall of an Egyptian monument.
3. Gharib had previously done experiments on bird flight.
4. Gharib and Graff tested their theory before applying it.
5. The success of the actual experiment was due to the high speed of the wind.
6. They found that, as the kite flew higher, the wind force got stronger.
7. The team decided that it was possible to use kites to raise very heavy stones.

Questions 8-13

Complete the summary below.

Choose NO MORE THAN TWO WORDS from the passage for each answer.

Write your answers In boxes 8-13 on your answer sheet, write

Addition evidence for theory of kite lifting

The Egyptians had (8)………………, which could lift large pieces of (9)……………….., and they knew how to use the energy of the wind from their skill as (10)………………. The discovery on one pyramid of an object which resembled a (11)…………….. suggests they may have experimented with (12) …………… In addition, over two thousand years ago kites used in china as weapons, as well as for sending (13)………………

Reading Passage 2

Endless Harvest

More than two hundred years ago, Russian explorers and fur hunters landed on the Aleutian Islands, a volcanic archipelago in the North Pacific, and learned of a land mass that lay farther to the north. The islands’ native inhabitants called this land mass Aleyska, the ‘Great Land’; today, we know it as Alaska.

The forty-ninth state to join the United States of America (in 1959), Alaska is fully one-fifth the size of the mainland 48 states combined. It shares, with Canada, the second longest river system in North America and has over half the coastline of the United States. The rivers feed into the Bering Sea and Gulf of Alaska -cold, nutrient-rich waters which support tens of millions of seabirds, and over 400 species of fish, shellfish, crustaceans, and molluscs. Taking advantage of this rich bounty, Alaska’s commercial fisheries have developed into some of the largest in the world.

According to the Alaska Department of Fish and Game (ADF&G), Alaska’s commercial fisheries landed hundreds of thousands of tonnes of shellfish and herring, and well over a million tonnes of groundfish (cod, sole, perch and pollack) in 2000. The true cultu,ral heart and soul of Alaska’s fisheries, however, is salmon. ‘Salmon,’ notes writer Susan Ewing in The Great Alaska Nature Factbook, ‘pump through Alaska like blood through a heart, bringing rhythmic, circulating nourishment to land, animals and people.’ The ‘predictable abundance of salmon allowed some native cultures to flourish,’ and ‘dying spawners* feed bears, eagles, other animals, and ultimately the soil itself.’ All five species of Pacific salmon -chinook, or king; chum, or dog; coho, or silver; sockeye, or red; and pink, or humpback -spawn** in Alaskan waters, and 90% of all Pacific salmon commercially caught in North America are produced there. Indeed, if Alaska was an independent nation, it would be the largest producer of wild salmon in the world. During 2000, commercial catches of Pacific salmon in Alaska exceeded 320,000 tonnes, with an ex-vessel value of over $US260 million.

Catches have not always been so healthy. Between 1940 and 1959, overfishing led to crashes in salmon populations so severe that in 1953 Alaska was declared a federal disaster area. With the onset of statehood, however, the State of Alaska took over management of its own fisheries, guided by a state constitution which mandates that Alaska’s natural resources be managed on a sustainable basis. At that time, statewide harvests totalled around 25 million salmon. Over the next few decades average catches steadily increased as a result of this policy of sustainable management, until, during the 1990s, annual harvests were well in excess of 100 million, and on several occasions over 200 million fish.

The primary reason for such increases is what is known as ‘In-Season Abundance-Based Management’. There are biologists throughout the state constantly monitoring adult fish as they show up to spawn. The biologists sit in streamside counting towers, study sonar, watch from aeroplanes, and talk to fishermen. The salmon season in Alaska is not pre-set. The fishermen know the approximate time of year when they will be allowed to fish, but on any given day, one or more field biologists in a particular area can put a halt to fishing. Even sport fishing can be brought to a halt. It is this management mechanism that has allowed Alaska salmon stocks -and, accordingly, Alaska salmon fisheries -to prosper, even as salmon populations in the rest of the United States are increasingly considered threatened or even endangered.

In 1999, the Marine Stewardship Council (MSC)*** commissioned a review of the Alaska salmon fishery. The Council, which was founded in 1996, certifies fisheries that meet high environmental standards, enabling them to use a label that recognises their environmental responsibility. The MSC has established a set of criteria by which commercial fisheries can be judged. Recognising the potential benefits of being identified as environmentally responsible, fisheries approach the Council requesting to undergo the certification process. The MSC then appoints a certification committee, composed of a panel of fisheries experts, which gathers information and opinions from fishermen, biologists, government officials, industry representatives, non-governmental organisations and others.

Some observers thought the Alaska salmon fisheries would not have any chance of certification when, in the months leading up to MSC’s final decision, salmon runs throughout western Alaska completely collapsed. In the Yukon and Kuskokwim rivers, chinook and chum runs were probably the poorest since statehood; subsistence communities throughout the region, who normally have priority over commercial fishing, were devastated.

The crisis was completely unexpected, but researchers believe it had nothing to do with impacts of fisheries. Rather, they contend, it was almost certainly the result of climatic shifts, prompted in part by cumulative effects of the el niiio/la niiia phenomenon on Pacific Ocean temperatures, culminating in a harsh winter in which huge numbers of salmon eggs were frozen. It could have meant the end as far as the certification process was concerned. However, the state reacted quickly, closing down all fisheries, even those necessary for subsistence purposes.

In September 2000, MSC announced that the Alaska salmon fisheries qualified for certification. Seven companies producing Alaska salmon were immediately granted permission to display the MSC logo on their products. Certification is for an initial period of five years, with an annual review to ensure that the fishery is continuing to meet the required standards.

Questions 14-20

Do the following statements agree with the information given in Reading Passage 2?

In boxes 14-20 on your answer sheet, write

• YES                                 if the statement agrees with the claims of the writer
• NO                                   if the statement contradicts the claims of the writer
• NOT GIVEN                if it is impossible to say what the writer thinks about this

14. The inhabitants of the Aleutian islands renamed their islands ‘Aleyska’.
15. Alaska’s fisheries are owned by some of the world’s largest companies.
16. Life in Alaska is dependent on salmon.
17. Ninety per cent of all Pacific salmon caught are sockeye or pink salmon.
18. More than 320,000 tonnes of salmon were caught in Alaska in 2000.
19. Between 1940 and 1959, there was a sharp decrease in Alaska’s salmon population.
20. During the 1990s, the average number of salmon caught each year was 100 million.

Questions 21 and 26

Complete each sentence with the correct ending, A-K, below.

Write the correct letter, A-K, in boxes 21-26 on your answer sheet.

1. to recognise fisheries that care for the environment.
2. to be successful.
3. to stop fish from spawning.
4. to set up environmental protection laws.
5. to stop people fishing for sports
6. to label their products using the MSC logo.
7. to ensure that fish numbers are sufficient to permit fishing.
8. to assist the subsistence communities in the region.
9. to freeze a huge number of salmon eggs.
10. to deny certification to the Alaska fisheries.
11. to close down all the fisheries

21. In Alaska, biologists keep a check on adult fish …..
22. Biologists have the authority …..
23. In-Season Abundance-Based Management has allowed the Alaska salmon fisheries …..
24. The Marine Stewardship Council (MSC) was established …..
25. As a result of the collapse of the salmon runs in 1999, the state decided …..
26. In September 2000, the MSC allowed seven Alaska salmon companies …..

Reading Passage 3

Effects Of Noise

In general, it is plausible to suppose that we should prefer peace and quiet to noise. And yet most of us have had the experience of having to adjust to sleeping in the mountains or the countryside because it was initially ‘too quiet’, an experience that suggests that humans are capable of adapting to a wide range of noise levels. Research supports this view. For example, Glass and Singer (1972) exposed people to short bursts of very loud noise and then measured their ability to work out problems and their physiological reactions to the noise. The noise was quite disruptive at first, but after about four minutes the subjects were doing just as well on their tasks as control subjects who were not exposed to noise. Their physiological arousal also declined quickly to the same levels as those of the control subjects.

But there are limits to adaptation and loud noise becomes more troublesome if the person is required to concentrate on more than one task. For example, high noise levels interfered with the performance of subjects who were required to monitor three dials at a time, a task not unlike that of an aeroplane pilot or an air-traffic controller (Broadbent, 1957). Similarly, noise did not affect a subject’s ability to track a moving line with a steering wheel, but it did interfere with the subject’s ability to repeat numbers while tracking (Finkelman and Glass, 1970).

Probably the most significant finding from research on noise is that its predictability is more important than how loud it is. We are much more able to ‘tune out’ chronic background noise, even if it is quite loud, than to work under circumstances with unexpected intrusions of noise. In the Glass and Singer study, in which subjects were exposed to bursts of noise as they worked on a task, some subjects heard loud bursts and others heard soft bursts. For some subjects, the bursts were spaced exactly one minute apart (predictable noise); others heard the same amount of noise overall, but the bursts

	Unpredictable Noise	Predictable Noise	Average
Loud Noise	40.1	31.8	35.9
Soft Noise	36.7	27.4	32.1
Average	38.4	29.6

occurred at random intervals (unpredictable noise). Subjects reported finding the predictable and unpredictable noise equally annoying, and all subjects performed at about the same level during the noise portion of the experiment. But the different noise conditions had quite different after-effects when the subjects were required to proofread written material under conditions of no noise. As shown in Table I the unpredictable noise produced more errors in the later proofreading task than predictable noise; and soft, unpredictable noise actually produced slightly more errors on this task than the loud, predictable noise.

Apparently, unpredictable noise produces more fatigue than predictable noise, but it takes a while for this fatigue to take its toll on performance.

Predictability is not the only variable that reduces or eliminates the negative effects of noise. Another is control. If the individual knows that he or she can control the noise, this seems to eliminate both its negative effects at the time and its after-effects. This is true even if the individual never actually exercises his or her option to turn the noise off (Glass and Singer, 1972). Just the knowledge that one has control is sufficient.

The studies discussed so far exposed people to noise for only short periods and only transient effects were studied. But the major worry about noisy environments is that living day after day with chronic noise may produce serious, lasting effects. One study, suggesting that this worry is a realistic one, compared elementary school pupils who attended schools near Los Angeles’s busiest airport with students who attended schools in quiet neighbourhoods (Cohen et al., 1980). It was found that children from the noisy schools had higher blood pressure and were more easily distracted than those who attended the quiet schools. Moreover, there was no evidence of adaptability to the noise. In fact, the longer the children had attended the noisy schools, the more distractible they became. The effects also seem to be long lasting. A follow-up study showed that children who were moved to less noisy classrooms still showed greater distractibility one year later than students who had always been in the quiet schools (Cohen et al, 1981 ). It should be noted that the two groups of children had been carefully matched by the investigators so that they were comparable in age, ethnicity, race, and social class.

Questions 27-29

Choose the correct letter, A, B. C or D.

Write the correct letter in boxes 27-29 on your answer sheet

27. The writer suggests that people may have difficulty sleeping in the mountains because
    1. humans do not prefer peace and quiet to noise.
    2. they may be exposed to short bursts of very strange sounds.
    3. humans prefer to hear a certain amount of noise while they sleep.
    4. they may have adapted to a higher noise level in the city.
28. In noise experiments, Glass and Singer found that
    1. problem-solving is much easier under quiet conditions.
    2. physiological arousal prevents the ability to work.
    3. bursts of noise do not seriously disrupt problem-solving in the long term.
    4. the physiological arousal of control subjects declined quickly.
29. Researchers discovered that high noise levels are not likely to interfere with the
    1. successful performance of a single task.
    2. tasks of pilots or air traffic controllers.
    3. ability to repeal numbers while tracking moving lines.
    4. ability to monitor three dials at once.

Questions 30-34

Complete the summary using the list of words and phrases, A-J. below.

Write the correct letter  A-J in boxes 30-34 on your answer sheet.

NB You may use any letter more than once.et.

Glass and Singer (1972) showed that situations in which there is intense noise have less effect on performance than circumstances in which (30) ……………………….. noise occurs. Subjects were divided into groups to perform a task. Some heard loud bursts of noise, others sort. For some subjects, the noise was predictable, while for others its occurrence was random. All groups were exposed to (31) ……………………. noise. The predictable noise group (32) ……………………. the unpredictable noise group on this task. In the second part of the experiment, the four groups were given a proofreading task to complete under conditions of no noise. They were required to check written material for errors. The group which had been exposed to unpredictable noise (33) ……………… the group which had been exposed to predictable noise. The group which had been exposed to loud predictable noise performed better than those who” had heard soft, unpredictable bursts. The results suggest that (34) ………………………… noise produces fatigue but that this manifests itself later.

A  no control over	B  unexpected	C  intense	D  the same amount of	E  performed better than
F  performed at about the same level as	G  no	H  showed more irritation than	I  made more mistakes than	J  different types of

Questions 35-40

Look at the following statements (Questions 35-40) and the lust of researchers below.

Match each statement with the correct researcher(s), A-E.

Write the correct letter A-E, in boxes 35-40 on your answer sheet.

NB You may use any letter more than once.

35. Subjects exposed to noise find it difficult at first to concentrate on problem-solving tasks.
36. Long-term exposure to noise can produce changes in behavior which can still be observed a year later.
37. The problems associated with exposure to noise do not arise if the subject knows they can make it stop.
38. Exposure to high-pitched noise results in more errors than exposure to low-pitched noise
39. Subjects find it difficult to perform three tasks at the same time when exposed to noise
40. Noise affects a subject’s capacity to repeat numbers while carrying out another task.

List of Researchers

1. Glass and Singer
2. Broadbent
3. Finke man and Glass
4. Cohen et al.
5. None of the above
   

Reading Passage 1 Pulling Strings to Build Pyramids Answers

1. true
2. false
3. not given
4. true
5. false
6. not given
7. true
8. (wooden) pulleys
9. stone
10. (accomplished) sailors
11. (modern) glider
12. flight
13. messages

Reading Passage 2 Endless Harvest Answers

14. false
15. not given
16. true
17. not given
18. true
19. true
20. false
21. G
22. E
23. B
24. A
25. K
26. F

Reading Passage 3 Effects of Noise Answers

27. D
28. C
29. A
30. B
31. D
32. F
33. I
34. B
35. A
36. D
37. A
38. E
39. B
40. C

Reading Passage 1

  Ant Intelligence

When we think of intelligent members of the animal kingdom, the creatures 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 demonstrate 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 in 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 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 basic 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 crafts are sophisticated when compared to the agricultural skills of humans five thousand years ago but have been totally overtaken by modem 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. Moreover, 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 can’t digest the cellulose in leaves – but some fungi can. The ants, therefore, cultivate these fungi in their nests, bringing 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 unchanged 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 the fungi suggests that the ants improve or modify the fungi by regularly swapping and sharing strains with neighboring 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 on 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 Wilson’s magnificent work for ant lovers, the Ants, describes a supercolony 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 kilometers.

Such enduring and intricately meshed levels of technical 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 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 continuously update 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 very 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 been Elaborate precautions were taken to prevent the foraging team using odour clues. Discussion now centers 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 has grown so attached to her laboratory ants that she feels she knows them as individuals – even without the paint spots used to mark them. It’s 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 step. Be careful of little lives.’

Questions 1-6

Do the following statements agree with the information given in the Reading Passage?

In boxes 1-6 on your answer sheet, write:

• YES                                 if the statement agrees with the claims of the writer
• NO                                   if the statement contradicts the claims of the writer
• NOT GIVEN                if it is impossible to say what the writer thinks about 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 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 farmers
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 own natall (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 neighboring ant colonies. In fact, the farming methods of ants could be said to be more advanced than human agribusiness, since they use (11)………………… methods, they do not affect the (12)……………… and do not waste.

A aphids	B agricultural	C cellulose	D exchanging
E energy	F fertilizers	G food	H Fungi
I growing	J interbreeding	K natural	L other species
M secretions	N sustainable	O environment

Reading Passage 2

Population Movement and Genetics

A Study of the origins and distribution of human populations used to be based on archaeological and fossil evidence. A number 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 Recent 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 World’. But was there one major wave of migration across the Bering 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 Americans 1 2.

C An important project, led by the biological anthropologist Robert Williams, focused on the variants (called Gm allotypes) of one particular protein -immunoglobulin 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 comparing 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 American 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 group. From this evidence it was deduced that there had been three major waves of migration across the Bering Strait. The first, Paleo-indian, 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 hunters, 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 conclusions? 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 Yucatán peninsula, Mexico, and Ticuna Indians in the Upper Amazon region of Brazil. As would have been predicted by Robert Williams’s work, all three groups appear to be descended from the same ancestral (Paleo-indian) 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 anthropologist 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 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 incisor shoveling (a scooping out on one or both surfaces of the tooth), single-rooted upper first premolars and triple-rooted lower first molars.

According to Turner, this ties in with the idea of a single Paleo-indian 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 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 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 Greenberg’s view. Dates given for the migrations should nevertheless be treated with caution, except where supported by hard archaeological evidence.

Questions 14-19

Reading Passage 2 has seven paragraphs, A-G.

Choose the correct heading 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 Headings

1. The results of the research into blood-variants
2. Dental Evidence
3. Greenberg’s analysis of the dental and linguistic evidence
4. Developments in the methods used to study early population movements
5. Indian migration from Canada to the U.S.A.
6. Further genetic evidence relating to the three-wave theory
7. Long-standing questions about prehistoric migration to America
8. Conflicting views of the three-wave theory, based on non-genetic evidence
9. Questions about the causes of prehistoric migration to America
10. How analysis of blood-variants measures the closeness of the relationship between different populations

14. Paragraph A
15. Paragraph B
16. Paragraph C
17. Paragraph D
18. Paragraph E
19. Paragraph F

Example Answer

Section G Viii

Questions 20 and 21

The discussion of Williams’s research indicates the periods at which early people are thought to have migrated along certain routes.

Route	Period (Number of years)
20………………………..	15,000 or more
21………………………..	600 to 700

Early Population Movement to the Americas

Questions 22-25

Reading Passage 2 refers to the three-wave theory of early migration to the Americas.

It also suggests in which of these three waves the ancestors of various groups of modern native Americans first reached the continent.

Classify the groups named in the table below as originating from

1. the first wave
2. the second wave
3. the third wave

Write the correct letter. A. B or C. in boxes 22-25 on your answer sheet.

Name of group	Wave number
Inuit	22……………………………..
Apache	23……………………………..
Prima-Papago	24……………………………..
Ticuna	25……………………………..

Questions 26

Choose the correct letter. A. B. C or D.

Write the correct letter in box 26 on your answer sheet.

26. Christy Turner’s research involved the examination of ….
    1. teeth from both prehistoric and modern Americans and Asians
    2. thousands of people who live in either the New or the Old World
    3. dental specimens from the majority of prehistoric Americans
    4. the eating habits of American and Asian populations

Reading Passage 3

Plans to protect the forests of Europe

Forests are one of the main elements of our natural heritage. The decline of Europe’s forests over the last decade and a half has led to an increasing awareness and understanding of the serious imbalances which threaten them. European countries are becoming increasingly concerned by major threats to European forests, threats which know no frontiers other than those of geography or climate: air pollution, soil deterioration, the increasing number of forest fires and sometimes even the mismanagement of our woodland and forest heritage. There has been a growing awareness of the need for countries to get together to co-ordinate their policies. In December 1990, Strasbourg hosted the first Ministerial Conference on the protection of Europe’s forests. The conference brought together 31 countries from both Western and Eastern Europe. The topics discussed included the coordinated study of the destruction of forests, as well as how to combat forest fires and the extension of European research programs on the forest ecosystem. The preparatory work for the conference had been undertaken at two meetings of experts. Their initial task was to decide which of the many forest problems of concern to Europe involved the largest number of countries and might be the subject of joint action. Those confined to particular geographical areas, such as countries bordering the Mediterranean or the Nordic countries, therefore, had to be discarded. However, this does not mean that in future they will be ignored.

As a whole, European countries see forests as performing a triple function: biological, economic and recreational. The first is to act as a ‘green lung’ for our planet; by means of photosynthesis, forests produce oxygen through the transformation of solar energy, thus fulfilling what for humans is the essential role of an immense, non-polluting power plant. At the same time, forests provide raw materials for human activities through their constantly renewed production of wood. Finally, they offer those condemned to spend five days a week in an urban environment an unrivalled area of freedom to unwind and take part in a range of leisure activities, such as hunting, riding and hiking. The economic importance of forests has been understood since the dawn of man – wood was the first fuel. The other aspects have been recognised only for a few centuries but they are becoming more and more important. Hence, there is a real concern throughout Europe about the damage to the forest environment which threatens these three basic roles. 

The myth of the ‘natural’ forest has survived, yet there are effectively no remaining ‘primary’ forests in Europe. All European forests are artificial, having been adapted and exploited by man for thousands of years. This means that a forest policy is vital, that it must transcend national frontiers and generations of people, and that it must allow for the inevitable changes that take place in the forests, in needs, and hence in policy. The Strasbourg conference was one of the first events on such a scale to reach this conclusion. A general declaration was made that a central place in any ecologically coherent forest policy must be given to continuity over time and to the possible effects of unforeseen events, to ensure that the full potential of these forests is maintained’.

That general declaration was accompanied by six detailed resolutions to assist national policy­making. The first proposes the extension and systematic sitting of surveillance sites to monitor forest decline. Forest decline is still poorly understood but leads to the loss of a high proportion of a tree’s needles or leaves. The entire continent and the majority of species are now affected: between 30% and 50% of the tree population. The condition appears to result from the cumulative effect of a number of factors, with atmospheric pollutants the principal culprits. Compounds of nitrogen and sulphur dioxide should be particularly closely watched. However, their effects are probably accentuated by climatic factors, such as drought and hard winters, or soil imbalances such as soil acidification, which damages to roots. The second resolution concentrates on the need to preserve the genetic diversity of European forests. The aim is to reverse the decline in the number of tree species or at least to preserve the ‘genetic material’ of all of them. Although forest fires do not affect all of Europe to the same extent the amount of damage caused the experts to propose as the third resolution that the Strasbourg conference considers the establishment of a European databank on the subject. All information used in the development of national preventative policies would become generally available. The subject of the fourth resolution discussed by the ministers was mountain forests. 

In Europe, it is undoubtedly the mountain ecosystem which has changed most rapidly and is most at risk. A thinly scattered permanent population and development of leisure activities, particularly skiing, have resulted in significant long-term changes to the local ecosystems. Proposed developments include a preferential research program on mountain forests. The fifth resolution relented the European research network on the physiology of trees, called  Euro Silva should support joint European research on tree diseases and their physiological and biochemical aspects. Each country concerned could increase “the number of scholarships and other financial support for doctoral theses and research projects in this area. Finally, the conference established the framework for a European research network on forest ecosystems. This would also involve harmonizing activities in individual countries as well as identifying a number of priority research topics relating to the protection of forests. The Strasbourg conference’s main concern was to provide for the future. This was the initial motivation, one now shared by all 31 participants representing 31 European countries. Their final text commits them to on-going discussion between government representatives with responsibility for forests. 

Questions 27-33

Do the following statements agree with the information given in Reading Passage 3?

In boxes 27-33 on your answer sheet, write:

• YES                                 if the statement agrees with the claims of the writer
• NO                                   if the statement contradicts the claims of the writer
• NOT GIVEN                if it is impossible to say what the writer thinks about this

27. Forest problems of Mediterranean countries are to be discussed at the next meeting of experts.
28. Problems in Nordic countries were excluded because they are outside the European – Economic Community.
29. Forests are a renewable source of raw material.
30. The biological functions of forests were recognised only in the twentieth century.
31. Natural forests still exist in parts of Europe.
32. Forest policy should be limited by national boundaries.
33. The Strasbourg conference decided that a forest policy must allow for the possibility of change.

Questions 34-39

Look at the following statements issued by the conference.

Which six of the following statements. A-J, refer to the resolutions that were issued?

Match the statements with the appropriate resolutions (Questions 34-39).

Write the correct letter. A-J. in boxes 34-39 on your answer sheet.

A  All kinds of species of trees should be preserved.
B  Fragile mountain forests should be given priority in research programs.
C  The surviving natural forests of Europe do not need priority treatment.
D  Research is to be better co-ordinate throughout Europe:
E  Information on forest fires should be collected and shared.
F  Loss Of leaves from trees should be more extensively and carefully monitored
G  Resources should be allocated to research into tree diseases.
H  Skiing should be encouraged in thinly populated areas.
I  Soil imbalances such as acidification should be treated with compounds of nitrogen and sulphur.
J  Information is to be systematically gathered on any decline in the condition of forests.

34. Resolution 1
35. Resolution 2
36. Resolution 3
37. Resolution 4
38. Resolution 5
39. Resolution 6

Questions 37-40

Complete the summary using the list of words, A-K, below. Write the correct letter A-K in boxes 37-40 on your answer sheet.

Sugestopedia uses a less direct method of suggestion than other techniques such as hypnosis. However, Lozanov admits that a certain amount of (37)……………… is necessary in order to convince students, even if this is just a (38)……………………. Furthermore, if the method is to succeed, teachers must follow a set procedure. Although Lozanov’s method has become quite (39)………………., the result of most other teachers using this method have been (40)……………………

A spectacular unpopular	B teaching	C lesson
D authoritarian	E unpopular	F ritual
G unspectacular	H placebo	I Involved
J appropriate	K well known

Reading Passage 1 Ant Intelligence Answers

1. FALSE
2. TRUE
3. NOT GIVEN
4. TRUE
5. FALSE
6. NOT GIVEN
7. C
8. M
9. F
10. D
11. N
12. O
13. E

Reading Passage 2 Population Movement and Genetics Answers

14. iv
15. vii
16. x
17. i
18. vi
19. ii
20. E
21. D
22. C
23. B
24. A
25. A
26. A

Reading Passage 3 Plans to protect the forests of Europe Answers

27. not given
28. false
29. true
30. false
31. false
32. false
33. true
34. J
35. A
36. E
37. B
38. G
39. D
40. B