IELTS Academic Reading Practice Test 414

The wandering albatross is the largest of all flying birds, measured not by weight but by the span of its wings. In a large male the distance from tip to tip may exceed three metres, and exceptional individuals approach three and a half. The wings are long and narrow, and a tendon at the shoulder locks them open, so that holding them out costs little muscular effort. A bird built on this pattern cannot take off by flapping from level ground; it needs wind, and above all it needs the open sea.

The species is confined to the Southern Ocean. It circles the globe between roughly the edge of the Antarctic ice and the fortieth parallel, and it is only rarely recorded north of the Tropic of Capricorn. Almost all its life is spent airborne or resting on the surface of the water, often hundreds of kilometres from land. It comes ashore only to breed, on remote islands such as South Georgia, the Crozet and Kerguelen archipelagos, the Prince Edward Islands and Macquarie Island, where the ground is open and the wind blows almost without interruption.

Flight is achieved almost entirely without flapping. The technique, known as dynamic soaring, exploits the fact that wind travels more slowly close to the waves, where friction with the water holds it back, than it does a few metres higher. The albatross climbs into the faster air, turns, and glides down across the boundary between the layers, gaining speed as it descends. It then pulls up into the slower air, using that speed to climb again, and repeats the manoeuvre in a series of sweeping arcs. A bird can travel hundreds of kilometres in this way without a single wingbeat.

Because the birds range so widely, most of what is known about their movements comes from instruments rather than observation. Satellite transmitters attached to breeding adults have shown that a single foraging trip may last a fortnight and cover several thousand kilometres, and that some individuals fly right around the Southern Ocean before returning to the nest. The birds feed mostly by day, though they can travel through the night, and weather appears to govern their routes as much as the search for food does.

Wandering albatrosses feed at the surface, taking squid, small fish and crustaceans, and they will readily eat carrion, including the carcasses of seals and whales, and waste thrown from ships. Unlike many seabirds they seldom dive more than a metre or two, and most prey is seized while the bird sits on the water. Two adaptations help. Glands above the eyes remove excess salt, which is excreted in a concentrated solution, and the stomach can hold quantities of oil that provide energy during long spells without food.

Breeding begins with a return to the colony, where birds that have nested before rejoin the same partner. Wandering albatrosses form pair bonds that last for many years, sometimes for life, and the bond is renewed each season by an elaborate courtship display of bowing, bill-clattering and spreading of the wings. Because raising a chick takes almost a year, a pair that succeeds normally breeds only every second year, while a pair that loses its egg early may try again the following season.

A single egg is laid, and both parents take turns to incubate it, each spell lasting several days while the other is at sea feeding. Incubation occupies about eleven weeks. Once the chick has hatched, the adults continue to share the work. For the first weeks one bird remains at the nest to guard the chick. The other spends long days at sea and returns with food, which it passes into the open bill. Later both parents hunt at the same time, leaving the young bird alone for long periods between visits.

The chick takes roughly nine months to grow and fledge, and it is fed throughout that time on partly digested meals. When it finally leaves, it may not touch land again for several years; birds ringed as chicks have been recovered thousands of kilometres away only months later. Most do not attempt to breed until they are about ten years old. Adults, in return, are long-lived, and individuals are known to have survived for more than forty years, so a single pair may raise only a handful of young in a lifetime.

The greatest danger the birds face is longline fishing. A vessel sets a line several tens of kilometres long, carrying thousands of baited hooks, and the albatrosses gather behind it to seize the bait as it sinks. Birds that swallow a hook are dragged under and drown. Measures that reduce the toll include streamers known as bird-scaring lines, which flap around the stern and keep the birds away, and setting the hooks at night, when most albatross species are less active. Weighting the line so that it sinks faster also helps.

On land the pressures are different. Rats and cats introduced by sailors to islands that had no land mammals take eggs and small chicks, and on some islands they have caused colonies to be abandoned. Eradication programmes work but are expensive and can only be attempted where human settlement is sparse. At sea the International Union for Conservation of Nature classifies the wandering albatross as Vulnerable, and several populations have declined. What remains uncertain is how far the birds can adapt to a changing climate: some researchers argue that shifts in wind patterns may alter the routes the birds take and the energy they expend, while others maintain that fishing pressure is so dominant that climate effects are, for now, secondary.

Owls are birds of prey that hunt mainly in the dark, and they do so with senses that differ sharply from those of the hawks and falcons that fly by day. There are roughly 250 species, found on every continent except Antarctica. Most are active between dusk and dawn, though a few, particularly in the far north, hunt in daylight. Their success at night rests on two abilities that are unusually well developed: vision that works in almost no light, and hearing sharp enough to locate a moving animal by sound alone.

The eyes are enormous in proportion to the skull and are shaped more like tubes than spheres, which leaves little room for the muscles that would move them. Instead the whole head turns, and the neck is adapted to allow a rotation of well over 180 degrees. The retina is densely packed with rod cells, which respond to faint light but give poor colour vision. Such eyes are superb in near darkness. In total darkness they are of no use whatever.

Hearing takes over where sight fails. The ears themselves are simple openings, one on each side of the head, but they sit behind a structure of stiffened feathers called the facial disc, which is shaped like a shallow dish and collects sound in the way that a satellite dish collects radio waves. In many species small muscles alter the shape of the disc, narrowing the area from which sound is gathered. In a few, notably the barn owl, the openings are set at different heights on the skull, and the skull itself is slightly asymmetrical.

That these structures are used for hunting has been demonstrated experimentally. A barn owl placed in a completely dark room will find and strike a mouse that is moving on the floor, and will do so repeatedly and accurately. If its ears are covered, or if sounds are played from a loudspeaker in another direction, the bird strikes at the loudspeaker instead. The birds can be trained to fly to a point in space from which a sound is coming, even when there is nothing to see, and their aim is remarkably precise in both the horizontal and the vertical plane.

The mechanism depends on comparison. A sound produced to one side of the bird reaches the nearer ear a fraction of a second before the farther one, and arrives there slightly louder. The difference in time gives the horizontal angle; the difference in loudness supplies the vertical angle. By turning its head until the two inputs match, the owl places itself directly in line with the source. The great grey owl of the northern forests carries the technique further, detecting the rustle of small rodents moving beneath a layer of snow.

None of this would work if the bird's own flight were noisy. Owl feathers are unusual in three respects. Along the front edge of each wing the outermost barbs end in a row of stiff, comb-like teeth. Along the trailing edge the barbs extend into a soft fringe. And the upper surface of the wing is covered by a fine, downy layer that gives it a velvety texture. The effect is that the air flowing over the wing separates and rejoins more gradually, and the small turbulent eddies that generate sound are damped down.

The result is a wing that is almost silent in flight, and the advantage is not only that the owl's approach goes unnoticed. Because the wing noise is so weak, the faint sounds made by prey are not masked by the rush of air over the owl's own feathers. Recordings confirm the difference: the flight of a barn owl is effectively inaudible to human hearing at more than a few metres, whereas a pigeon of similar size produces a steady rustle.

How the three feather features work together is still disputed. Wind-tunnel measurements and computer models of aerodynamics have shown that the comb reduces turbulence near the leading edge, while the fringe breaks up the larger eddies shed behind the wing; but their relative importance, and the precise mechanism by which the soft upper surface absorbs sound, remain matters of argument. There is also a cost: the modifications that reduce noise are thought to make the wing slightly less efficient, which may explain why the fishing owls of Asia and Africa, whose prey cannot hear them coming, lack these features.

Not every owl conforms to the pattern. Several species have no comb at all. The largest, such as the eagle owl of Europe and Asia, can take prey as heavy as a hare or a young fox, and rely more on strength and eyesight than on hearing. The tawny owl, common in European woodland, hunts from a perch; the two-note hoot traditionally written as tu-whit, tu-whoo is produced by two birds answering each other. The snowy owl, which nests in the open Arctic and hunts by day in summer, has a smaller facial disc than the woodland species.

Engineers have taken an interest. Aircraft and wind turbines generate noise in much the same way as a wing does, and surfaces that copy the owl's fringe have been tested on the trailing edges of fan blades. Whether such designs will work at the speeds and scales involved is not yet clear, but the owl, which has been solving the problem for millions of years, remains a useful model.

An internship is a period of work, lasting a few months, that is intended to give a young person experience of an occupation. In medicine, teaching and accountancy the placement is part of a qualification and is normally paid or at least financed. In media, politics, fashion, law and many charities, however, a different model survives: the unpaid internship. The arrangement is common enough that most graduates in these fields either undertake one or know someone who has. Whether it should be prohibited is argued with force, because the practice sits at the intersection of training, privilege and employment law.

Employers who offer unpaid placements defend them on three grounds. The first is that an intern consumes time: someone must design the tasks, supervise the work and correct mistakes. The second is that a short placement is a sensible trial before a paid job is offered. The third is cost. A small magazine, a local law firm or a charity with a thin budget may be able to offer a desk and a mentor but not a salary. Ban unpaid internships, these employers maintain, and many placements will vanish rather than become paid. The people who lose will be those who most need a first line on a curriculum vitae.

Students are less united than the argument suggests. Those who have completed a worthwhile placement often describe it as the decisive step in their career, and some resent the suggestion that they were exploited. Others tell a different story: filing, photocopying and answering telephones for months, with no training and no prospect of a job. The difference between the two experiences is rarely the label on the advertisement. It is whether the organisation treats the intern as a learner or as an inexpensive source of labour. Student unions have therefore begun to demand not simply pay but clear learning agreements and limits on hours.

Economists approach the question from the structure of the labour market rather than from individual cases. An unpaid placement is, in effect, a job that pays in experience. If experience genuinely raises productivity, the arrangement can be efficient: the intern acquires skills and the employer recovers the cost of teaching them. The difficulty is that access to such experience depends on the ability to forgo wages. A candidate whose parents can cover rent can accept an offer that a candidate from a poorer household must refuse. The labour market then selects not the most able entrants but the most subsidised ones.

Regulators frame the issue in terms of legal status. In many countries the law distinguishes between a trainee who is mainly learning and a worker who is mainly producing for an employer. A genuine student on a recognised course may be exempt from minimum wage rules; a person who performs the same tasks as paid staff, under the same supervision, is harder to classify as anything but an employee. Enforcement, however, is weak. Inspectors rarely visit small offices, and an intern who complains risks losing a reference. The result is that the law on paper is clearer than in practice, and employers wishing to use unpaid labour can often do so without much fear of challenge.

The distributional consequences are easy to state and hard to remedy. Unpaid work is cheapest for those who have somewhere to live in an expensive city and someone to pay the bills. It is most expensive for those who must work to support themselves or send money home. Over time, this filtering shapes who enters journalism, politics and the arts, and therefore which experiences those professions understand. A newsroom staffed only by people who could afford to work for nothing will not see the world in the same way as one drawn from a wider pool. That is an argument about the quality of the work, not merely about fairness.

A ban is one response, but it is a blunt instrument. If every unpaid placement were prohibited overnight, some would become paid, some would disappear, and some would reappear as courses with fees. The last outcome would be the worst, since it would preserve the advantage of wealthy candidates while adding a price. A better approach is to narrow the exemption. Unpaid work should be lawful only where it is a required part of an accredited course, lasts a limited number of weeks, involves no productive tasks that an employee would otherwise do, and includes reimbursement of travel and lunch. Outside those conditions, the minimum wage should apply.

My view is that the case for a qualified ban is strong. The freedom to work without pay is not worth protecting when the alternative is not a paid job but exclusion from a profession. Employers' warnings about lost places deserve attention, but they are predictions rather than findings, and the placements most likely to disappear are those that offer least. A rule that forces organisations to choose between training properly and paying properly would improve the average quality of internships, even if it reduced their number. The narrow educational exemption should be kept, but it should be policed, not assumed.

What remains uncertain is how such a rule would be enforced across borders and in small organisations, and whether universities would resist losing placements they currently advertise. These are real questions, but they do not alter the principle that a profession should not recruit through a gate that only the wealthy can pass.