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READING PASSAGE 2
You should spend about 20 minutes on Questions 14-26, which are based on Reading Passage 2 on pages 6 and 7.
TWO WINGS AND A TOOLKIT
A research team at Oxford University discover the remarkable toolmaking skills of New
Caledonian crowns
Betty and her mate Abel are captive crows in the care of Alex Kacelnik, an expert in animal behavior at Oxford University. They belong to a forest-dwelling species of bird (Corvus
moneduloides) confined to two islands in the South Pacific. New Caledonian crows are tenacious predators, and the only birds that habitually use a wide selection of self-made tools to find food. One of the wild crows’ cleverest tools in the crochet hook, made by detaching a side twig from a larger one, leaving enough of the larger twig to shape into a hook. Equally cunning is a tool
crafted from the barbed vine-leaf, which consists of a central rib with paired leaflets each with a rose-like thorn at the top, which remains as a ready-made hook to prise out insects from awkward cracks.
The crows also make an ingenious tool called a padanus probe from padanus tree leaves. The tool has a broad base, sharp tip, a row of tiny hooks along one edge, and a tapered shape created by the crow nipping and tearing to form a progression of three or four steps along the other edge of the leaf. What makes this tool special is that they manufacture it to a standard design, as if following a set of instructions. Although it is rare to catch a crow in the act of clipping out a padanus probe, we do have ample proof of their workmanship: the discarded leaves from which the tools are cut. The remarkable thing that these ‘counterpart’ leaves tell us is that crows consistently produce the same design every time. With no in-between or trail versions. It’s left the researchers wondering whether, like people, they envisage the tool before they start and perform the actions they know are needed to make it. Research has revealed that genetics plays a part in the less sophisticated toolmaking skills of finches in the Galapagos islands. No one knows if that’s also the case for New Caledonian crows, but it’s highly unlikely that their toolmaking skills are hardwired into the brain. “The picture so far points to a combination of cultural transmission-from parent birds to their young-and individual resourcefulness”, says Kacelnik.
In a test at Oxford, Kacelnik’s team offered Betty and Abel an original challenge-food in a bucket at the bottom of a ‘well’. The only way to get the food was to hook the bucket out by its handle. Given a choice of tools- a straight length of wire and one with a hooked end- the birds immediately picked the hook, showing that they did indeed understand the functional properties of the tool.
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But do they also have the foresight and creativity to plan the construction of their tools?
It appears they do. In one bucket-in-the-well test. Abel carried off the hook, leaving Betty with nothing but the straight wire. ‘What happened next was absolutely amazing’, says Kacelnik. She wedged the tip of the wire into a crack in a plastic dish and pulled the other end to fashion her own hook. Wild crows don’t have access to pliable, bendable material that retains its shape, and Betty’s only similar experience was a brief encounter with some pipe cleaners a year earlier. In nine out of ten further tests, she again made hooks and retrieved the bucket.
The question of what’s going on in a crow’s mind will take time and a lot more experiments to answer, but there could be a lesson in it for understanding our own evolution. Maybe our ancestors, who suddenly began to create symmetrical tools with carefully worked edges some 1.5 million years ago, didn’t actually have the sophisticated mental abilities with which we credit them. Close scrutiny of the brains of New Caledonian crows might provide a few pointers to the special attributes they would have needed. ‘If we’re lucky we may find specific developments in the brain that set these animals apart,’ says Kacelnik.
One of these might be a very strong degree of laterality-the specialization of one side of the brain to perform specific tasks. In people, the left side of the brain controls the processing of complex sequential tasks, and also language and speech. One of the consequences of this is thought to be right-handedness. Interestingly, biologists have noticed that most padanus proves are cut from the left side of the leaf, meaning that the handedness. The team thinks this reflects the fact that the left side of the crow’s brain is specialized to handle the sequential processing required to make complex tools.
Under what conditions might this extraordinary talent have emerged in these two species? They are both social creatures, and wide-ranging in their feeding habits. These factors were probably important but, ironically, it may have been their shortcomings that triggered the evolution of toolmaking. Maybe the ancestors of crows and humans found themselves in a position of where they couldn’t make the physical adaptations required for survival – so they had to change their behavior instead. The stage was then set for the evolution of those rare cognitive skills that produce sophisticated tools. New Caledonian crows may tell us what those crucial skills are.
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Questions 14-17
Label the diagrams below.
Choose NO MORE THAN TWO WORDS from the passage for each answer. Write your answers in boxes 14-17 on your answer sheet.
THREE TOOLS MADE BY CROWS
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Questions 18-23
Do the following statements agree with the information given in Reading Passage 2? In boxes 18-23 on your answer sheet, write
TRUE if the statements agree with the information FALSE if the statements contradicts the information NOT GIVEN if there is no information on this
18 there appears to be a fixed patter for the padanus probe’s construction.
19 there is plenty of evidence to indicate how the crows manufacture the padanus prove 20 crows seem to practice a number of times before making a usable padanus probe
21 the researchers suspect the crows have a mental images of the padanus probe before
they create it.
22 research into how the padanus probe is made as helped to explain the toolmaking
skills of many other bird species.
23 the researchers believe the ability to make the padanus probe is passed down to the
crows in their genes
Questions 24-26
Choose THREE letters, A-G
Write the correct letters in boxes 24-26 on you answer sheet.
According to the information in the passage, which THREE of the following features are probably common to both New Caledonian crows and human beings? A keeping the same mate for life B having few natural predators
C having a bias to the right when working D being able to process sequential tasks E living in extended family groups F eating a variety of foodstuffs G being able to diverse habitats
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READING PASSAGE 3
You should spend about 20 minutes on Questions 27-40, which are based on Reading Passage 3 on pages 10 and 11.
How did writing begin?
Many theories, few answers
The Sumerians, an ancient people of the Middle East, had a story explaining the invention of writing more than 5000 years ago. It seems a messenger of the king of Uruk arrived at the court of a distant ruler so exhausted that he was unable to deliver the oral message. So the king set down the words of his next messages on a clay tablet. A charming story, whose retelling at a recent symposium at the university of Pennsylvania amused scholars. They smiled at the absurdity of a letter which the recipient would not have been able to read. They also doubted that the earliest writing was a direct rendering of speech. Writing more likely began as a separate, symbolic system of communication and only later merger with spoken language.
Yet in the story the Sumerians, who lived in Mesopotamia, in what is now southern Iraq, seemed to understand writing’s transforming function. As Dr Holly Pittman, director of the University’s Center for Ancient Studies, observed, writing ‘ arose out of the need to store and transmit information…over time and space’.
In exchanging interpretations and information, the scholars acknowledged that they still had no fully satisfying answers to the questions of how and why writing developed. Many favourated an explanation of writing’s origins in the visual arts, pictures becoming increasingly abstract and eventually representing spoken words. Their views clashed with a widely held theory among archaeologists writing developed from the pieces of clay that Sumerian accountants used as tokens to keep track of goods.
Archaeologists generally concede that they have no definitive answer to the question of whether writing was invented only once, or arose independently in several places, such as Egypt, the Indus Valley, China, Mexico and Central America. The preponderance of archaeological data shows that the urbanizing Sumerians were the first to develop writing, in 3200 or 3300 BC. These are the dates for many clay tablets in an early form of cuneiform, a script written by pressing the end of a sharpened stick into wet clay, found at the site of the ancient city of Uruk. the baked clay tablets bore such images as pictorial symbols of the names of people, place and things connected with government and commerce. The Sumerian script gradually evolved from the pictorial to the abstract, but did not at first represent recorded spoken language.
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