IELTS CAM Inspired 17 - Reading Test 4 with Practice Test, Answers And Explanation
Luyện tập đề IELTS Online CAM Inspired 17 - Reading Test 4 được lấy từ cuốn sách IELTS CAM Inspired 17 với trải nghiệm thi IELTS trên máy và giải thích đáp án chi tiết bằng Linearthinking, kèm answer key và list từ vựng IELTS cần học trong bài đọc.
IELTS Mock Test 17 - Reading Test 4 With Practice Test, Answers And Explanation
Passage
❓ Câu hỏi passage 1
Question 1 - 6
Do the following statements agree with the information given in the Reading Passage?
TRUE if the statement agrees with the information
FALSE if the statement contradicts the information
NOT GIVEN if there is no information on this
1
On the island, it is the insects themselves, rather than human activity, that are directly responsible for most of the forest being lost.
2
Even though biodiversity on the island is generally declining, several kinds of insect-eating bat are doing well.
3
In Almeida's view, the pest control the bats provide does little to relieve farmers financially.
4
Globally, the island ranks among the top locations for safeguarding bat species.
5
No other native bat on the island is as numerous as the lesser sheath-tailed bat.
6
Of all the pests referred to, the rice leaf-roller is the one that causes farmers the greatest losses.
Question 7 - 13
Choose ONE WORD ONLY from the passage for each answer.
Almeida's team: an outline of the research
Purpose
to establish how bats feed on the farmland next to Lore Piru National Park
Method
high-frequency detectors used to locate the bats' preferred feeding grounds
DNA testing of the bats'
7.
Findings
The bats:
foraged most heavily over hillside rice fields
preyed on insects that harm rice,
8.
, sugarcane, nuts and fruit
help limit the spread of illness by eating mosquitoes and
9.
Local feeling about the bats is divided:
they give people food that is high in
10.
any building they settle in is regarded as
11.
they carry real weight in the region's
12.
Recommendation
to keep bat numbers up, farmers should set up special
13.
Passage
❓ Câu hỏi passage 2
Question 14 - 18
Reading Passage 2 has 6 sections, A-F.
Which section contains the following information?
Write the correct letter, A-F.
14
a claim that the earliest nation to undergo industrialisation was not especially literate
15
a list of the different kinds of historical records that were combined to build the database
16
mention of a possible minimum level of education needed before it can affect an economy
17
a description of how a guild punished someone who had broken its rules
18
a warning that money spent on education may not produce growth where other obstacles remain
Question 19 - 22
Complete the summary below.
Choose ONE WORD ONLY from the passage for each answer.
Demographic reconstruction of two Alpine communities
The records assembled by Marogg and her team open a window onto the lives of many ordinary villagers — and onto those of their as well — over more than two and a half centuries. The cousins Barbla and Ursina Cadonau, for instance, were told off for studying books at a moment when they ought to have been listening to the . Another figure, Anna Barbla Tscharner, was brought to the attention of the linen-weavers' guild in 1738 after she ignored its rules; her eventual punishment was a . Episodes such as these show how the guilds could shut people out of a and stop skilled workers from practising their craft.
Question 23 - 24
Choose TWO letters, A-E.
Which TWO of the following statements does the writer make about literacy rates in Section B?
A
Reading was common across the German-speaking territories in that period.
B
Researchers have now clearly demonstrated that literate populations become wealthier.
C
A country's literacy tends to improve as its economy grows stronger.
D
England's early industrial success rested on the reading skills of its population.
E
Hardly any research has examined whether literacy raises people's earnings.
Question 25 - 26
Choose TWO letters, A-E.
Which TWO of the following statements does the writer make in Section F about guilds in German-speaking central Europe between 1600 and 1900?
A
They resisted anything likely to weaken their control over a line of work.
B
They were mainly made up of prosperous traders.
C
They helped young people to acquire a craft.
D
They kept fuller records than guilds in other regions.
E
They tried to stop workers relocating in search of employment.
Passage
❓ Câu hỏi passage 3
Question 27 - 32
Reading Passage 3 has 8 paragraphs, A-H.
Which paragraph contains the following information?
Write the correct letter, A-H.
27
a mention of blindfold play from earlier historical periods
28
a description of the mental effort the activity demands of a player
29
a statement that Gareyev's gift does not reach beyond the game
30
the reason scientists became interested in Gareyev
31
an account of what matters most to Gareyev
32
an explanation of why the final phase of a game can be hard
Question 33 - 36
Do the following statements agree with the information given in the Reading Passage?
TRUE if the statement agrees with the information
FALSE if the statement contradicts the information
NOT GIVEN if there is no information on this
33
In an earlier simultaneous display, Gareyev avoided defeat in every game he took part in.
34
People have only begun playing chess blindfold in relatively modern times.
35
Gareyev finds the opening stage of a game the easiest to retain in his mind.
36
The Melbourne team was the first anywhere to carry out research on blindfold chess players.
Question 37 - 40
Complete the summary below.
Choose ONE WORD ONLY from the passage for each answer.
How the research was carried out
The team began by assessing Gareyev's ; in one exercise, for instance, he had to repeat a string of , first in the sequence he had heard and then backwards. His scores proved unremarkable, yet the brain scans exposed an unusually high degree of among the areas of Gareyev's brain that govern the focusing of attention. The scans also pointed to possible extra strength in the parts of his brain that deal with input.
DOL IELTS Đình Lực
21/10/2026
📖 Bài đọc passage 1
Bats to the rescue
How the bats of Sulawesi are helping to protect the forest
Few corners of the world see the tension between farming and conservation run as high as it does on Sulawesi. Each year, close to two percent of the island's forest is handed over to agriculture, and most of that loss traces back to one crop: rice, the mainstay of the local diet. The sequence is simple — swarms of insect pests spoil so much of the harvest that subsistence farmers, needing to make up the shortfall, clear still more forest for fresh paddy. Habitats disappear and biodiversity drains away as a result, and yet not every species is losing out. A few of the island's insect-eating bats are actually thriving as never before, which matters greatly to farmers and conservationists alike.
This is where Tomás Almeida enters the story. A zoologist at the University of Coimbra, he is devoted to conservation and to bats, and above all to how bats respond to what people do to the land, deforestation especially. His latest study reveals that a whole set of bat species are quietly doing an essential job for Sulawesi's rice growers, feasting on the very insect swarms that would otherwise strip the fields bare. That service, Almeida contends, might lift enough of the financial burden from farmers to make turning forest into fields far less tempting.
Roughly a quarter of every mammal species on Sulawesi is a bat, and more than fifty kinds are found on the island and nowhere else — a count that places it among the most important spots on Earth for keeping this group of animals safe.
Working at the head of an international team, Almeida found that several of the island's own bats have turned the disturbance of their habitat to good use, picking off the insect clouds that hang over the rice. Among them are the Minahasa mouse-eared bat, Reinwardt's long-fingered bat, the lesser sheath-tailed bat and the Celebes free-tailed bat.
'These "winners" are doing Sulawesi a valuable turn at no cost, holding pest numbers in check,' Almeida says. 'Six species of bat, we found, hunt the insects that attack rice, the paddy armyworm and the rice leaf-roller among them. What those pests destroy leaves the island's farmers under intense financial strain, and it is that strain which pushes deforestation along.'
In the journal Farming, Ecosystems and Biodiversity, where the project has now appeared, the team examined how insect-eating bats feed on the belt of farmland fringing Lore Piru National Park, towards the island's south-east.
To work out where the bats preferred to feed, Almeida's team reached for state-of-the-art ultrasonic detectors, capturing more than nine hundred bat 'feeding buzzes' — the quick bursts of echolocation a bat gives off as it closes in on prey — at forty-eight different locations. The guano the animals left behind at each spot was then run through DNA barcoding.
The recordings put the matter beyond doubt: the bats foraged far more over the rice than inside unbroken forest — five times as much above fields on level ground, and fourteen times as much above those on hillsides — plainly favouring these landscapes of human making. Poor drainage and lost nutrients, the team suggests, leave such crops more open to infestation, and where the pests gather the bats follow. The DNA confirmed as much: each of the six species had been feeding on pests of real economic weight. Rice gains most of all, the study found, but the bats were also taking the pests of other crops — the twig-boring beetle that ruins cocoa, the cane leafhopper, the almond seed-wasp and the citrus peel-miner that spoils fruit.
'Elsewhere — in the United States and in northern Italy — the value of bats for keeping pests down has been shown already,' noted Sofia Marques of the University of Porto, who co-wrote the paper. 'On Sulawesi, though, ours is the first study to document it, and here the stakes for farming and conservation are unusually high.'
The islanders may owe their bats on yet another count. Blamed though the animal often is for carrying sickness, the evidence Almeida's team gathered points the other way: Sulawesi's bats consume not only the pests of crops but mosquitoes too — behind malaria, dengue and filariasis — along with the blackflies responsible for river blindness.
The relationship, Almeida stresses, is a complicated one. In times of scarcity, bats become a vital source of protein for local people, and even the children will go after them. Besides roosting in trees, the bats will sometimes settle inside buildings, where they are unwelcome, since the rooms they take over are thought to be left polluted. And yet these same animals are bound up with sacred caves and with the ancestors — beings caught between two worlds — which earns them a weighty place in local folklore. There is a catch, though: even as the bats gain from farming, the deforestation they help to slow is destroying the sites where they roost, which may tell on their numbers over time. 'With a little help,' Almeida says, 'farmers could encourage this give-and-take by putting up bat boxes.'
Higher bat numbers, Almeida and his colleagues are convinced, could lift the size of harvests and help make rural livelihoods sustainable; what is needed now, they say, is further work to measure just how big that benefit is. 'I'm very hopeful,' he adds. 'Offer nature a hand and its recovery only speeds up.'
A. Professor Liesl Marogg, an economic historian at the University of Basel, has spent much of the past decade assembling a vast database documenting the lives of villagers in the Swiss canton of Graubünden between 1620 and 1880. The team she leads has drawn together parish registers, guild ledgers, tax rolls, village censuses and court records, and lately some 7,000 handwritten inventories cataloguing more than 800,000 personal belongings owned by ordinary men and women across nearly three centuries. It was Marogg who, over two decades ago, came upon these inventories in the parish archives of two Alpine communities, and she is convinced they may settle a question that has long baffled economists - why so little evidence exists that education actually causes a nation's economy to grow.
B
'Education makes us more productive, helps us design better tools and lets us earn more,' Marogg observes, 'so surely it must be vital to economic growth? And yet, looking back over history, we find no sign that a highly literate population caused a country to industrialise any sooner.' England, she points out, had no more than average literacy by the European standards of the seventeenth to nineteenth centuries, and yet it industrialised before anyone else and its economy expanded quickly. The German-speaking lands and Scandinavia, by contrast, enjoyed some of the finest literacy rates on the continent throughout those years, and still their economies crept forward slowly and industrialisation came to them late. 'Even present-day studies that compare many countries have struggled to show that education produces growth,' she adds, 'though there is no shortage of evidence for the opposite - that growth pushes up levels of education.'
C
The inventories record everything people owned at the great turning points of marriage, remarriage and death, preserving the villagers' entire material world - from goatskins and prayer books to copper pans and embroidered waistcoats. Farming gear and workshop tools show how a household made its living, while books and writing equipment such as quills and slates hint at how its members came by their learning. The tax rolls, for their part, set a value on farms, workshops, holdings and debts; the way people signed their names, or could not, together with the ages they claimed for themselves, reveals how far they could read, write and reckon; and the court records lay bare the obstacles - the doings of the guilds above all - that held manufacturing back. Earlier studies had usually leaned on a single measure to connect education with economic growth: the number of schools and printing presses, perhaps, or school enrolment, or the share who could sign their name. Marogg's database instead supplies many such measures for the very same individuals, so that literacy, numeracy, wealth and industriousness can be traced together, person by person, over the long run.
D
On top of a full demographic reconstruction of everyone who lived in the two communities, Marogg and her colleagues have built this immense record of possessions. 'We can follow the very same people - and the offspring who came after them - right across three hundred years of educational and economic change,' she says. Whole lives have risen up out of the documents. Take the cousins Barbla and Ursina Cadonau, both twenty-two, who in 1698 were scolded for poring over printed books in church instead of attending to the preacher. 'That tells us they were still sharpening their reading a good decade after their schooldays had ended,' Marogg says. Or take Anna Barbla Tscharner, a forty-eight-year-old unmarried woman from the mountain village of Tarnau, whom the linen-weavers' guild reprimanded in 1738 for spinning and finishing cloth against its statutes. When she went on taking work reserved for the guild's male members, she was summoned before the guild court and ordered to pay a penalty worth a third of a maidservant's yearly wage. By today's standards it was a slight act of defiance, yet it belongs to an age when statutes in the German-speaking lands and elsewhere governed who could enter the labour market. The guilds' hold did more than keep people from using their skills; by barring outsiders from each trade, it smothered even the simplest industrial innovation.
E
Now that the gathering of data is over, Marogg says the time has come 'to put the big questions'. One way to test whether education drives economic growth is to 'hold wealth constant' - to track, across the years, a set of people who all own the same amount. Where wealth stays put, one can begin to see whether education went together with, say, planting new crops or taking up labour-saving machines like the mechanical loom. The team also means to ask which part of education it was that pulled people toward more productive and inventive work - was it reading, arithmetic, the owning of books, the years spent in school? And was there a threshold, a tipping point, that had to be reached before education made any difference to economic performance?
F
'German-speaking central Europe,' Marogg explains, 'makes a superb laboratory for testing theories of economic growth.' All through the seventeenth, eighteenth and nineteenth centuries its people read widely and owned no shortage of books, and still the region remained poor. Its guilds and merchant associations, moreover, held enormous power and legislated against anything that might chip away at their monopolies; throughout the region they blocked the movement of workers from place to place and beat back any change that might loosen their grip. 'What is starting to come clear,' she says, 'is that other barriers can hold back whatever good education might do an economy - and that has a lesson for the present. Enormous sums go into better schooling in the developing world, yet the spending may yield no growth if restrictions stop people - women and the poor above all - from turning their education to productive use. Where economic institutions are badly built, education cannot lead to growth.'
G
* guilds: associations of craftspeople or merchants that controlled the practice of a trade in a town or region
A. Later this year, a chess player called Timur Gareyev intends to face almost 60 opponents at once, though the number is not the hard part. Every one of his rivals will play in the ordinary way, with the board in full view; Gareyev alone will wear a blindfold throughout. Feats like this test the limits of human performance. At 31, he is already a striking figure in the small world of sightless chess: fond of vivid clothing and eye-catching haircuts, he also chases his thrills through cave diving. His playing credentials are not in doubt either. In a nine-hour session in 2011, he ran 35 games in his head at once, taking 31 wins and losing none. That feat has become his trademark, and he now bills himself as the Blindfold King.
B
To an outsider, playing without sight of the board can look like something beyond ordinary human capacity, but the practice is far from new; exhibitions of it stretch back many centuries. The earliest such contest recorded in Europe took place in Venice in the fourteenth century. Much later, in 1960, the Hungarian grandmaster Janos Bekesi carried 46 games at once in his memory, and by the end of a session lasting more than a full day he had won 41 of them.
C
Gareyev first sat down to a chessboard as a five-year-old in his native Kazakhstan, taught the moves by an uncle. He played his first competitive event at eight, and the taste for tournaments quickly took hold. By 15 he had become the youngest grandmaster his country had ever produced, and soon afterwards he relocated to Australia, where, while still a student, he helped steer his university to the national title for the first time in its history. By 2011 he was rated among Australia's five strongest players.
D
Skilled players can pick up the knack of playing blind almost without noticing. Chess by its nature means working candidate moves through the head to see where each one leads, and from this habit players build up a store of the shapes the pieces form, their attacks and defences. "You rebuild the position in your mind," Gareyev says. "Plenty of players could do what I do." The genuine difficulty lies in holding several games at once. The location of every piece on each board has to be committed to memory, brought back exactly when it is wanted, revised after each move, and then stored away again securely, so that attention can shift to the next board. Opening positions are surprisingly slippery to retain, precisely because they are so dull; and the closing stages are punishing too, as tiredness sets in. A weary Gareyev finds his recall growing unreliable, and will sometimes commit to a move on the strength of only a half-remembered layout of the pieces.
E
Gareyev's talents have attracted notice well outside chess circles. Hoping to work out how a handful of people manage such mental feats, a research team at the University of Melbourne invited him in for testing, and the first findings are now in. "For a strong player, seeing a game through with the eyes shut is not really a stretch," said Katarina Voss, who heads a memory laboratory at the university. "What is extraordinary about Timur, and about a very small number of others, is how many games they can keep running at the same time. I find it simply staggering."
F
The scientists began with a battery of standard recall tests, gauging how well Gareyev could keep numbers, images and words in mind. In one familiar exercise, the subject hears a run of digits and must repeat them back, both in the given order and in reverse; seven or so is the usual limit. "On none of these ordinary measures did he stand out," Voss noted. "Aside from chess itself, we found nothing he was outstandingly good at." The scans, though, told a different story. With Gareyev lying inside the scanner, Voss examined how tightly his brain regions were linked, and the images revealed far more signalling than is typical between the parts that make up what is termed the frontoparietal control network. Among the 58 other people scanned for comparison, only a single individual rated more highly. "That network comes into play in almost any demanding task," Voss said. "It lets you direct your attention, hold the rules in your head, and judge when to act and when to hold back."
G
That was not the only unusual thing the scans turned up. They also indicated that the network Gareyev uses to handle spatial information, the mental map of where each piece stands on a board, was more richly interconnected with the rest of his brain than is normal. The regions organising this sense of layout and position may, it seems, carry unusually strong links to other areas, and so work more powerfully than they would in most people. The analysis is still provisional, but it may offer the earliest clue to Gareyev's exceptional gift.
H
For the record itself, Gareyev is aiming to hold 57 blindfold games at once over roughly 19 hours, and he will have to win 80 per cent of them to take the title. "The winning percentage isn't something I lose sleep over, it's never really been a problem for me," he said. "What matters most to me about blindfold chess is that I've found the one thing I can give myself to completely. I've missed having an obsession."
Few corners of the world see the tension between farming and conservation run as high as it does on Sulawesi. Each year, close to two percent of the island's forest is handed over to agriculture, and most of that loss traces back to one crop: rice, the mainstay of the local diet. The sequence is simple — swarms of insect pests spoil so much of the harvest that subsistence farmers, needing to make up the shortfall, clear still more forest for fresh paddy. Habitats disappear and biodiversity drains away as a result, and yet not every species is losing out. A few of the island's insect-eating bats are actually thriving as never before, which matters greatly to farmers and conservationists alike.
This is where Tomás Almeida enters the story. A zoologist at the University of Coimbra, he is devoted to conservation and to bats, and above all to how bats respond to what people do to the land, deforestation especially. His latest study reveals that a whole set of bat species are quietly doing an essential job for Sulawesi's rice growers, feasting on the very insect swarms that would otherwise strip the fields bare. That service, Almeida contends, might lift enough of the financial burden from farmers to make turning forest into fields far less tempting.
Roughly a quarter of every mammal species on Sulawesi is a bat, and more than fifty kinds are found on the island and nowhere else — a count that places it among the most important spots on Earth for keeping this group of animals safe.
Working at the head of an international team, Almeida found that several of the island's own bats have turned the disturbance of their habitat to good use, picking off the insect clouds that hang over the rice. Among them are the Minahasa mouse-eared bat, Reinwardt's long-fingered bat, the lesser sheath-tailed bat and the Celebes free-tailed bat.
'These "winners" are doing Sulawesi a valuable turn at no cost, holding pest numbers in check,' Almeida says. 'Six species of bat, we found, hunt the insects that attack rice, the paddy armyworm and the rice leaf-roller among them. What those pests destroy leaves the island's farmers under intense financial strain, and it is that strain which pushes deforestation along.'
In the journal Farming, Ecosystems and Biodiversity, where the project has now appeared, the team examined how insect-eating bats feed on the belt of farmland fringing Lore Piru National Park, towards the island's south-east.
To work out where the bats preferred to feed, Almeida's team reached for state-of-the-art ultrasonic detectors, capturing more than nine hundred bat 'feeding buzzes' — the quick bursts of echolocation a bat gives off as it closes in on prey — at forty-eight different locations. The guano the animals left behind at each spot was then run through DNA barcoding.
The recordings put the matter beyond doubt: the bats foraged far more over the rice than inside unbroken forest — five times as much above fields on level ground, and fourteen times as much above those on hillsides — plainly favouring these landscapes of human making. Poor drainage and lost nutrients, the team suggests, leave such crops more open to infestation, and where the pests gather the bats follow. The DNA confirmed as much: each of the six species had been feeding on pests of real economic weight. Rice gains most of all, the study found, but the bats were also taking the pests of other crops — the twig-boring beetle that ruins cocoa, the cane leafhopper, the almond seed-wasp and the citrus peel-miner that spoils fruit.
'Elsewhere — in the United States and in northern Italy — the value of bats for keeping pests down has been shown already,' noted Sofia Marques of the University of Porto, who co-wrote the paper. 'On Sulawesi, though, ours is the first study to document it, and here the stakes for farming and conservation are unusually high.'
The islanders may owe their bats on yet another count. Blamed though the animal often is for carrying sickness, the evidence Almeida's team gathered points the other way: Sulawesi's bats consume not only the pests of crops but mosquitoes too — behind malaria, dengue and filariasis — along with the blackflies responsible for river blindness.
The relationship, Almeida stresses, is a complicated one. In times of scarcity, bats become a vital source of protein for local people, and even the children will go after them. Besides roosting in trees, the bats will sometimes settle inside buildings, where they are unwelcome, since the rooms they take over are thought to be left polluted. And yet these same animals are bound up with sacred caves and with the ancestors — beings caught between two worlds — which earns them a weighty place in local folklore. There is a catch, though: even as the bats gain from farming, the deforestation they help to slow is destroying the sites where they roost, which may tell on their numbers over time. 'With a little help,' Almeida says, 'farmers could encourage this give-and-take by putting up bat boxes.'
Higher bat numbers, Almeida and his colleagues are convinced, could lift the size of harvests and help make rural livelihoods sustainable; what is needed now, they say, is further work to measure just how big that benefit is. 'I'm very hopeful,' he adds. 'Offer nature a hand and its recovery only speeds up.'
B. 'Education makes us more productive, helps us design better tools and lets us earn more,' Marogg observes, 'so surely it must be vital to economic growth? And yet, looking back over history, we find no sign that a highly literate population caused a country to industrialise any sooner.' England, she points out, had no more than average literacy by the European standards of the seventeenth to nineteenth centuries, and yet it industrialised before anyone else and its economy expanded quickly. The German-speaking lands and Scandinavia, by contrast, enjoyed some of the finest literacy rates on the continent throughout those years, and still their economies crept forward slowly and industrialisation came to them late. 'Even present-day studies that compare many countries have struggled to show that education produces growth,' she adds, 'though there is no shortage of evidence for the opposite - that growth pushes up levels of education.'
C. The inventories record everything people owned at the great turning points of marriage, remarriage and death, preserving the villagers' entire material world - from goatskins and prayer books to copper pans and embroidered waistcoats. Farming gear and workshop tools show how a household made its living, while books and writing equipment such as quills and slates hint at how its members came by their learning. The tax rolls, for their part, set a value on farms, workshops, holdings and debts; the way people signed their names, or could not, together with the ages they claimed for themselves, reveals how far they could read, write and reckon; and the court records lay bare the obstacles - the doings of the guilds above all - that held manufacturing back. Earlier studies had usually leaned on a single measure to connect education with economic growth: the number of schools and printing presses, perhaps, or school enrolment, or the share who could sign their name. Marogg's database instead supplies many such measures for the very same individuals, so that literacy, numeracy, wealth and industriousness can be traced together, person by person, over the long run.
D. On top of a full demographic reconstruction of everyone who lived in the two communities, Marogg and her colleagues have built this immense record of possessions. 'We can follow the very same people - and the offspring who came after them - right across three hundred years of educational and economic change,' she says. Whole lives have risen up out of the documents. Take the cousins Barbla and Ursina Cadonau, both twenty-two, who in 1698 were scolded for poring over printed books in church instead of attending to the preacher. 'That tells us they were still sharpening their reading a good decade after their schooldays had ended,' Marogg says. Or take Anna Barbla Tscharner, a forty-eight-year-old unmarried woman from the mountain village of Tarnau, whom the linen-weavers' guild reprimanded in 1738 for spinning and finishing cloth against its statutes. When she went on taking work reserved for the guild's male members, she was summoned before the guild court and ordered to pay a penalty worth a third of a maidservant's yearly wage. By today's standards it was a slight act of defiance, yet it belongs to an age when statutes in the German-speaking lands and elsewhere governed who could enter the labour market. The guilds' hold did more than keep people from using their skills; by barring outsiders from each trade, it smothered even the simplest industrial innovation.
E. Now that the gathering of data is over, Marogg says the time has come 'to put the big questions'. One way to test whether education drives economic growth is to 'hold wealth constant' - to track, across the years, a set of people who all own the same amount. Where wealth stays put, one can begin to see whether education went together with, say, planting new crops or taking up labour-saving machines like the mechanical loom. The team also means to ask which part of education it was that pulled people toward more productive and inventive work - was it reading, arithmetic, the owning of books, the years spent in school? And was there a threshold, a tipping point, that had to be reached before education made any difference to economic performance?
F. 'German-speaking central Europe,' Marogg explains, 'makes a superb laboratory for testing theories of economic growth.' All through the seventeenth, eighteenth and nineteenth centuries its people read widely and owned no shortage of books, and still the region remained poor. Its guilds and merchant associations, moreover, held enormous power and legislated against anything that might chip away at their monopolies; throughout the region they blocked the movement of workers from place to place and beat back any change that might loosen their grip. 'What is starting to come clear,' she says, 'is that other barriers can hold back whatever good education might do an economy - and that has a lesson for the present. Enormous sums go into better schooling in the developing world, yet the spending may yield no growth if restrictions stop people - women and the poor above all - from turning their education to productive use. Where economic institutions are badly built, education cannot lead to growth.'
G. * guilds: associations of craftspeople or merchants that controlled the practice of a trade in a town or region
B. To an outsider, playing without sight of the board can look like something beyond ordinary human capacity, but the practice is far from new; exhibitions of it stretch back many centuries. The earliest such contest recorded in Europe took place in Venice in the fourteenth century. Much later, in 1960, the Hungarian grandmaster Janos Bekesi carried 46 games at once in his memory, and by the end of a session lasting more than a full day he had won 41 of them.
C. Gareyev first sat down to a chessboard as a five-year-old in his native Kazakhstan, taught the moves by an uncle. He played his first competitive event at eight, and the taste for tournaments quickly took hold. By 15 he had become the youngest grandmaster his country had ever produced, and soon afterwards he relocated to Australia, where, while still a student, he helped steer his university to the national title for the first time in its history. By 2011 he was rated among Australia's five strongest players.
D. Skilled players can pick up the knack of playing blind almost without noticing. Chess by its nature means working candidate moves through the head to see where each one leads, and from this habit players build up a store of the shapes the pieces form, their attacks and defences. "You rebuild the position in your mind," Gareyev says. "Plenty of players could do what I do." The genuine difficulty lies in holding several games at once. The location of every piece on each board has to be committed to memory, brought back exactly when it is wanted, revised after each move, and then stored away again securely, so that attention can shift to the next board. Opening positions are surprisingly slippery to retain, precisely because they are so dull; and the closing stages are punishing too, as tiredness sets in. A weary Gareyev finds his recall growing unreliable, and will sometimes commit to a move on the strength of only a half-remembered layout of the pieces.
E. Gareyev's talents have attracted notice well outside chess circles. Hoping to work out how a handful of people manage such mental feats, a research team at the University of Melbourne invited him in for testing, and the first findings are now in. "For a strong player, seeing a game through with the eyes shut is not really a stretch," said Katarina Voss, who heads a memory laboratory at the university. "What is extraordinary about Timur, and about a very small number of others, is how many games they can keep running at the same time. I find it simply staggering."
F. The scientists began with a battery of standard recall tests, gauging how well Gareyev could keep numbers, images and words in mind. In one familiar exercise, the subject hears a run of digits and must repeat them back, both in the given order and in reverse; seven or so is the usual limit. "On none of these ordinary measures did he stand out," Voss noted. "Aside from chess itself, we found nothing he was outstandingly good at." The scans, though, told a different story. With Gareyev lying inside the scanner, Voss examined how tightly his brain regions were linked, and the images revealed far more signalling than is typical between the parts that make up what is termed the frontoparietal control network. Among the 58 other people scanned for comparison, only a single individual rated more highly. "That network comes into play in almost any demanding task," Voss said. "It lets you direct your attention, hold the rules in your head, and judge when to act and when to hold back."
G. That was not the only unusual thing the scans turned up. They also indicated that the network Gareyev uses to handle spatial information, the mental map of where each piece stands on a board, was more richly interconnected with the rest of his brain than is normal. The regions organising this sense of layout and position may, it seems, carry unusually strong links to other areas, and so work more powerfully than they would in most people. The analysis is still provisional, but it may offer the earliest clue to Gareyev's exceptional gift.
H. For the record itself, Gareyev is aiming to hold 57 blindfold games at once over roughly 19 hours, and he will have to win 80 per cent of them to take the title. "The winning percentage isn't something I lose sleep over, it's never really been a problem for me," he said. "What matters most to me about blindfold chess is that I've found the one thing I can give myself to completely. I've missed having an obsession."
