IELTS Academic Reading Test 3 with Answers

You should spend about 20 minutes on Questions 1–13.

The oldest trees on Earth

High in the White Mountains of eastern California, on pale slopes of crumbling limestone where the wind rarely stops and almost nothing else will grow, stands a scattering of small, twisted trees. They are not tall, and to a passing visitor they may look half dead. Yet the Great Basin bristlecone pine is the oldest known individual tree on the planet: several of these specimens were already ancient when the pyramids were being built, and the eldest of them has been alive for close to five thousand years. Certain colonies of plants that spread by cloning themselves are older still, but no other single organism of this kind has stood in one place for so long.

What is most surprising is that the bristlecone owes its longevity not to comfort but to hardship. The trees that grow lowest down the mountain, in deeper soil and gentler conditions, are the ones that die youngest. Those clinging to the harshest, driest, most exposed ridges are the ones that endure. The reason lies in the wood itself. Because the tree grows at an extraordinarily slow rate – adding, in a poor season, almost nothing at all to its girth – the wood it produces is exceptionally dense and heavily saturated with resin, which makes it strongly resistant to insects, fungi and decay. Slow growth, in other words, is not a weakness but the tree’s chief defence. The bristlecone is economical in other ways too. Each of its needles may stay on the branch for as long as forty years, so the tree need not spend precious energy replacing its foliage every season. The very bleakness of the site protects it as well: so little vegetation grows on the bare rock between the trees that fire, which sweeps through denser forests lower down, rarely finds enough fuel to spread.

The bristlecone survives, too, by giving up. As a tree ages, much of its trunk simply dies, the bark stripped away by wind-driven ice and sand until only a narrow ribbon of living tissue remains, winding up the trunk to feed a single surviving branch. The rest stands bare and polished, like driftwood. A tree may lose nine-tenths of itself in this way and continue to grow for another thousand years.

These defences, however, are no protection against the changes now reaching the high slopes. As the climate warms, bark beetles that could never previously survive at such altitudes are moving upwards, and they have begun to attack trees that have stood untouched for millennia. A second danger is a fungus, introduced from another continent, which spread rapidly through related pines at lower elevations and has now been detected among the bristlecones. There have been human threats as well. In the past, trees were felled by researchers who wished to count their rings and establish their age – one specimen cut down in the 1960s turned out, too late, to be the oldest then known to science. Even the dead wood is at risk: because it is so beautifully weathered, pieces of it are carried off by collectors as souvenirs, removing a record that took centuries to form.

That record is the reason scientists guard these groves so carefully. Every ring in a bristlecone trunk preserves the conditions of a single year, and because dead trunks lie undecayed on the ground for thousands of years, their rings can be matched to those of living trees to build an unbroken calendar stretching back almost ten millennia. It is one of the most precise records of past climate that exists anywhere.

The bristlecone pine, then, is both a survivor and an archive. It has outlasted empires by growing as slowly as possible in a place where nothing else would try – and it now faces, in its final refuge, the one thing it never had to face before.

You should spend about 20 minutes on Questions 14–26.

Catching water from the clouds

On the southern edge of Morocco, where the Sahara begins, the village communities scattered around Mount Boutmezguida have always lived with too little water. Rain falls rarely and unpredictably. For generations the wells sank lower each year, and the task of fetching what water there was fell almost entirely to the women and girls of the village, who might spend three or four hours of every day walking to a well and carrying containers home. Girls missed school because of it. And yet, for much of the year, water drifts past the mountain in enormous quantities – not as rain, but as fog.

Since 2015 that fog has been harvested. Along the exposed ridges above the villages stand rows of tall rectangular frames, each holding a fine mesh stretched tight against the wind. As the fog rolls in off the Atlantic, tiny droplets of water suspended in the air strike the threads of the mesh and cling to them. The droplets merge, grow heavy, and trickle downwards into a gutter running along the base of each frame. From there the water flows through pipes to storage tanks, and is then filtered, mixed with well water and piped onward to taps in the houses below. The whole system works by gravity: because the collectors stand above the villages, no pump is needed at any point, and the installation requires no electricity at all. It is now among the largest fog-harvesting projects anywhere in the world, though it is not the first – the technique was developed decades earlier by researchers in Chile, who put up the first serious collectors in the 1980s.

The effect on daily life has been considerable. Water arrives in the village itself, and the hours once lost to fetching it have been returned to the women who used to make the journey. School attendance among girls has risen. Households have begun small gardens. Because the supply no longer depends on how deep a well can be sunk, families have a reason to stay rather than move to the cities.

The system has real limitations, however. The fog is not constant: it forms reliably only during certain months of the year, and in the dry season the nets may hang empty for weeks, so the villages must still rely on their wells for part of the year. The mesh is fragile in the way that all large, thin surfaces are fragile, and violent storms have destroyed entire rows of collectors, which then have to be rebuilt at considerable expense. The nets also lose efficiency as they clog with the fine dust that blows in from the desert, so each frame must be washed regularly by hand – slow work on a steep ridge. Lower down, the pipes that carry the water have on occasion been damaged by animals belonging to herders, and repairs to a broken line can take days. Perhaps the greatest weakness is financial: the project was built with money from outside the region, and it continues to depend on funding from foreign donors and charities rather than on income of its own, which makes its long-term future uncertain.

Even so, the idea is spreading. Similar collectors have since been put up in Chile, Peru, Ethiopia and elsewhere, wherever fog is dependable and rain is not. They will never irrigate a farm or supply a city. But for a village on a dry mountainside, a net that quietly pulls drinking water out of the passing air is a technology of a rare and useful kind: simple, silent, and almost free to run.

You should spend about 20 minutes on Questions 27–40.

In defence of forgetting

We treat memory as a virtue and forgetting as a failure. A good memory is something to be admired; a poor one is something to apologise for. An entire industry has grown up around the promise of improving our recall, and the loss of memory is among the things people say they fear most about growing old. Forgetting, in this account, is simply memory going wrong – a leak in a bucket that ought to hold. Even the language we use takes this for granted: we speak of losing a memory, as though anything that goes must have been worth keeping, and as though the mind were a container whose only virtue is that it does not lose things. But a considerable body of research now points in the opposite direction. Forgetting, it suggests, is not a fault in the system. It is part of how the system works.

Our discomfort with forgetting has deepened as it has become possible to avoid it. Not long ago, a holiday produced a handful of photographs and a few uncertain recollections; now it produces four hundred images, automatically dated, located and stored for ever. Every message we send is archived, every appointment recorded, every question answered by a device we no longer need to remember anything to use. We have quietly handed over to our machines a task that human beings once had to perform for themselves, and in doing so we have created something genuinely new: a life in which almost nothing is ever discarded.

What such a life might be like was glimpsed a century ago, in the case of a newspaper reporter examined over many years by a Russian psychologist. The man could recall, without apparent effort, lists of numbers, tables of nonsense syllables, and conversations from decades earlier. He seemed to have no upper limit. Yet his life was not enviable. Every word he heard summoned a crowd of images so vivid that he struggled to follow a simple story, and he found metaphor and poetry almost impenetrable, since he could not hear a phrase without seeing it literally. Above all, he could not generalise. To recognise that many different chairs are all chairs, a mind must let go of what makes each one distinct – and his mind refused. Drowning in particulars, he could not arrive at ideas.

This points to what forgetting is actually for. A memory that kept everything would be a memory in which nothing could be found; the useful pruning that goes on beneath our awareness – the steady discarding of what is no longer needed, the trimming away of detail that has stopped earning its place – is what leaves the mind able to reach the things that matter. Forgetting is not the enemy of thinking. It is the gardener.

Laboratory work supports the point. In one line of research, volunteers memorising word lists were instructed to forget some of the items; they later recalled the remaining words better than volunteers who had been asked to retain everything, as though clearing the shelf had made the rest easier to see. Other studies have examined people who have recently moved house, and found that the old address does not merely fade – it actively obstructs, intruding at the moment the new one is wanted, which suggests that information which has passed its usefulness gets in the way of what we now need. A study published in 2018 examined visitors to a museum who photographed the exhibits, and found that they remembered less about the objects afterwards than visitors who had simply looked: handing the job to the camera appeared to weaken the memory it was meant to preserve. And research on sleep indicates that the brain spends part of the night weakening and eliminating connections built during the day, disposing of what it has judged unnecessary while we rest.

None of this is to romanticise forgetting. The erosion of memory by disease is a genuine affliction and nothing about it is useful; there is a difference between a mind that discards and a mind that is disintegrating. But for the ordinary, everyday forgetting that we scold ourselves for – the mislaid name, the vanished afternoon – a certain calm seems in order. It is not evidence that something is broken. Remembering everything is not the goal; it is the failure state. The mind that lets go is not losing its grip. It is doing its job.