Copy your neighbour
THERE’S no animal that symbolises rainforest diversity quite as spectacularly as the tropical butterfly. Anyone lucky enough to see these creatures flitting between patches of sunlight cannot fail to be impressed by the variety of their patterns. But why do they display such colourful exuberance? Until recently, this was almost as pertinent a question as it had been when the 19th-century naturalists, armed only with butterfly nets and insatiable curiosity, battled through the rainforests. These early explorers soon realised that although some of the butterflies’ bright colours are there to attract a mate, others are warning signals. They send out a message to any predators: “Keep off, we’re predicting poisonous.” And because wearing certain patterns affords protection, other species copy them. Biologists use the term mimicry rings for these clusters of impostors and their evolutionary idol.
But here’s the conundrum. “Classical mimicry theory says that only a single ring should be found in any one area,” explains George Beccaloni of the Natural History Museum, London. The idea is that in each locality there should be just the one pattern that best protects its wearers. Predators would quickly learn to avoid it and eventually all mimetic species in a region should converge upon it. “The fact that this is patently not the case has been one of the major problems in mimicry research,” says Beccaloni. In pursuit of a solution to the mystery of mimetic exuberance, Beccaloni set off for one of the megacentres for butterfly diversity, the point where the western edge of the Amazon basin meets the foothills of the Andes in Ecuador. “It’s exceptionally rich, but comparatively well collected, so I pretty much knew what was there, says Beccaloni.” The trick was to work out how all the butterflies were organised and how this related to mimicry.”
Working at the Jatun Sacha Biological Research Station on the banks of the Rio Napo, Beccaloni focused his attention on agroup of butterflies called ithomiines. These distant relatives of Britain’s Camberwell Beauty are abundant throughout Central and South America and the Caribbean. They are famous for their bright colours, toxic bodies and complex mimetic relationships. “They can comprise up to 85 per cent of the individuals in a mimicry ring and their patterns are mimicked not just by butterflies, but by other insects as diverse as damselflies and true bugs,” says Philip DeVries of the Milwaukee Public Museum’s Center for Biodiversity Studies.
Even though all ithomiines are poisonous, it is in their interests to evolve to look like one another because predators that learn to avoid one species will also avoid others that resemble it. This is known as Mullerian mimicry. Mimicry rings may also contain insects that are not toxic, but gain protection by looking likes a model species that is: an adaptation called Batesian mimicry. So strong is an experienced predator’s avoidance response that even quite inept resemblance gives some protection. “Often there will be a whole series of species that mimic, with varying degrees of verisimilitude, a focal or model species,” says John Turner from the University of Leeds. “The results of these deceptions are some of the most exquisite examples of evolution known to science.” In addition to colour, many mimics copy behaviours and even the flight pattern of their model species.
But why are there so many different mimicry rings? One idea is that species flying at the same height in the forest canopy evolve to look like one another. “It had been suggested since the 1970s that mimicry complexes were stratified by flight height,” says DeVries. The idea is that wing colour patterns are camouflaged against the different patterns of light and shadow at each level in the canopy, providing a first line of defence, against predators.” But the light patterns and wing patterns don’t match very well,” he says. And observations show that the insects do not shift in height as the day progresses and the light patterns change. Worse still, according to DeVries, this theory doesn’t explain why the model species is flying at that particular height in the first place.
“When I first went out to Ecuador, I didn’t believe the flight height hypothesis and set out to test it,” says Beccaloni.”A few weeks with the collecting net convinced me otherwise. They really flew that way.” What he didn’t accept, however, was the explanation about light patterns. “I thought, if this idea really is true, and I can work out why, it could help explain why there are so many different warning patterns in any one place. Then we might finally understand how they could evolve in such a complex way.” The job was complicated by the sheer diversity of species involved at Jatun Sacha. Not only were there 56 ithomiine butterfly species divided among eight mimicry rings, there were also 69 other insect species, including 34 day-flying moths and a damselfly, all in a 200-hectare study area. Like many entomologists before him, Beccaloni used a large bag-like net to capture his prey. This allowed him to sample the 2.5 metres immediately above the forest floor. Unlike many previous workers, he kept very precise notes on exactly where he caught his specimens.
The attention to detail paid off. Beccaloni found that the mimicry rings were flying at two quite separate altitudes. “Their use of the forest was quite distinctive,” he recalls. “For example, most members of the clear¬winged mimicry ring would fly close to the forest floor, while the majority of the 12 species in the tiger-winged ring fly high up.” Each mimicry ring had its own characteristic flight height.
However, this being practice rather than theory, things were a bit fuzzy. “They’d spend the majority of their time flying at a certain height. But they’d also spend a smaller proportion of their time flying at other heights,” Beccaloni admits. Species weren’t stacked rigidly like passenger jets waiting to land, but they did appear to have a preferred airspace in the forest. So far, so good, but he still hadn’t explained what causes the various groups of ithomiines and their chromatic consorts to fly in formations at these particular heights.
Then Beccaloni had a bright idea. “I started looking at the distribution of ithomiine larval food plants within the canopy,” he says. “For each one I’d record the height to which the host plant grew and the height above the ground at which the eggs or larvae were found. Once I got them back to the field station’s lab, it was just a matter of keeping them alive until they pupated and then hatched into adults which I could identify.”
Questions 1 – 5
The reading Passage has seven paragraphs A-I.
Which paragraph contains the following information?
Write the correct letter A-I, in boxes 1-5 on your answer sheet.
NB You may use any letter more than once.
1 Criticism against flight height theory of butterfly
2 Explained why Beccaloni carried out research in Ecuador.
3 Different mimicry ring flies at different height
4 The method of catching butterfly by Beccaloni
5 Not all Mimicry patterns are toxic information sent out from insects.
Do the following statements agree with the information given in Reading Passage 1
In boxes 6-11 on your answer sheet, write
TRUE if the statement is true
FALSE if the statement is false
NOT GIVEN if the information is not given in the passage
6 All butterflies’ colour of wing reflect the sense of warning to other predator.
7 Insects may imitate butterflies’ wing pattern as well.
8 Flying Altitude of butterfly is determined by their food.
9 Beccaloni agreed with flight height hypothesis and decide to reassure its validity.
10 Jatun Sacha has the riches diversity of breeds in the world.
11 Beecaloni has more detailed records on the location of butterfly collection than others.
Choose the correct letter, A, B, C or D
Write your answers in boxes 12-13 on your answer sheet.
12 Which is correct about butterflies flight altitude ?
A Flight height theory already established
B Butterfly always flies at a certain height
C It is like the airplane’s flying phenomenon
D Each butterfly has its own favorable height
13 Which is correct about Beccaloni next investigation after flight height?
A Some certain statistics have already been collected
B Try to find connections between larval height and adult ones
C It’s very difficult to raise butterfly larval
D Different larval favors different kinds of trees
What are you laughing at?
We like to think that laughing is the height of human sophistication. Our big brains let us see the humour in a strategically positioned pun, an unexpected plot twist or a clever piece of word play. But while joking and wit are uniquely human inventions, laughter certainly is not. Other creatures, including chimpanzees, gorillas and even rats, chuckle. Obviously, they don’t crack up at Homer Simpson or titter at the boss’s dreadful jokes, but the fact that they laugh in the first place suggests that sniggers and chortles have been around for a lot longer than we have. It points the way to the origins of laughter, suggesting a much more practical purpose than you might think.
There is no doubt that laughing typical involves groups of people. ‘Laughter evolved as a signal to others – it almost disappears when we are alone,’ says Robert Provine, a neuroscientist at the University of Maryland. Provine found that most laughter comes as a polite reaction to everyday remarks such as ‘see you later’, rather than anything particularly funny. And the way we laugh depends on the company we’re keeping. Men tend to laugh longer and harder when they are with other men, perhaps as a way of bonding. Women tend to laugh more and at a higher pitch when men are present, possibly indicating flirtation or even submission.
To find the origins of laughter, Provine believes we need to look at play. He points out that the masters of laughing are children, and nowhere is their talent more obvious than in the boisterous antics, and the original context is play,’ he say. Well-known primate watchers, including Dian Fossey and Jane Goodall, have long argued that chimps laugh while at play. The sound they produce is known as a pant laugh. It seems obvious when you watch their behavior – they even have the same ticklish spots as we do. But remove the context, and the parallel between human laughter and a chimp’s characteristic pant laugh is not so clear. When Provine played a tape of the pant laughs to 119 of his students, for example, only two guessed correctly what it was.
These findings underline how chimp and human laughter vary. When we laugh the sound is usually produced by chopping up a single exhalation into a series of shorter with one sound produced on each inward and outward breath. The question is: does this pant laughter have the same source as our own laughter? New research lends weight to the idea that it does. The findings come from Elke Zimmerman, head of the Institute for Zoology in Germany, who compared the sounds made by babies and chimpanzees in response to tickling during the first year of their life. Using sound spectrographs to reveal the pitch and intensity of vocalizations, she discovered that chimp and human baby laughter follow broadly the same pattern. Zimmerman believes the closeness of baby laughter to chimp laughter supports the idea that laughter was around long before humans arrived on the scene. What started simply as a modification of breathing associated with enjoyable and playful interactions has acquired a symbolic meaning as an indicator of pleasure.
Pinpointing when laughter developed is another matter. Humans and chimps share a common ancestor that lived perhaps 8 million years ago, but animals might have been laughing long before that. More distantly related primates, including gorillas, laugh, and anecdotal evidence suggests that other social mammals nay do too. Scientists are currently testing such stories with a comparative analysis of just how common laughter is among animals. So far, though, the most compelling evidence for laughter beyond primates comes from research done by Jaak Panksepp from Bowling Green State University, Ohio, into the ultrasonic chirps produced by rats during play and in response to tickling.
All this still doesn’t answer the question of why we laugh at all. One idea is that f laughter and tickling originated as a way of sealing the relationship between mother and child. Another is that the reflex response to tickling is protective, alerting us to the presence of crawling creatures that might harm us or compelling us to defend the parts of our bodies that are most vulnerable in hand-to-hand combat. But the idea that has gained most popularity in recent years is that laughter in response to tickling is a way for two individuals to signal and test their trust in one another. This hypothesis starts from the observation that although a little tickle can be enjoyable, if it goes on too long it can be torture. By engaging in a bout of tickling, we put ourselves at the mercy of another individual, and laughing is a signal that we laughter is what makes it a reliable signal of trust according to Tom Flamson, a laughter researcher at the University of California, Los Angeles. ‘Even in rats, laughter, tickle, play and trust are linked. Rats chirp a lot when they play, ‘syas Flamson. ‘These chirps can be aroused by tickling. And they get bonded to us as a result, which certainly seems like a show of trust.’
We’ll never know which animal laughed the first laugh, or why. But we can be sure it wasn’t in response to a prehistoric joke. The funny thing is that while the origins of laughter are probably quite serious, we owe human laughter and our language-based humor to the same unique skill. While other animals pant, we alone can control our breath well enough to produce the sound of laughter. Without that control there would also be no speech – and no jokes to endure.
Questions 14 – 19
Look at the following research findings (questions 1-6) and the list of people below. Match each finding with the correct person, A, B, C or D.
Write the correct letter, A, B, C or D, in boxes 1-6 on your answer sheet.
NB You may use any letter more than once.
A Tom Flamson
B Elke Zimmerman
C Robert Provine
D Jaak Panksepp
14 Babies and chimps produce similar sounds of laughter .
15 Primates are not the only animals who produce laughter Pan
16 Laughter also suggests that we feel safe and easy with others.
17 Laughter is a response to polite situation instead of humour.
18 Animal laughter evolved before human laughter
19 Laughter is a social activity.
Questions 20 – 23
Complete the summary using the list of words, A-K, below.
Write the correct letter, A-K, in boxes 7-10 on your answer sheet.
Some researchers believe that laughter first evolved out of 20…………………… . Investigation has revealed that human and chimp laughter may have the same 21 …………………… . Besides, scientists have been aware that 22…………………… laugh, however, it now seems that laughter might be more
widespread than once we thought. Although the reasons why humans started to laugh are still unknown, it seems that laughter may result from the 23…………………… we feel with another person
A evolution B chirps C origins D voice
E confidence F rats G primates H response
I play J children K tickling
Questions 24 – 26
Do the following statements agree with the information given in Reading Passage 1? In boxes 11-13 on your answer sheet, write
TRUE if the statement is true
FALSE if the statement is false
NOT GIVEN if the information is not given in the passage
24 Both men and women laugh more when they are with members of the same sex.
25 Primates lack sufficient breath control to be able to produce laughs the way humans do.
26 Chimpanzees produce laughter in a wider range of situations than rats do
Try this memory test: Study each face and compose a vivid image for the person’s first and last name Rose Leo, for example, could be a rosebud and a lion. Fill in the blanks on the next page. The Examinations School at Oxford University is an austere building of oak-paneled rooms, large Gothic windows, and looming portraits of eminent dukes and earls. It is where generations of Oxford students have tested their memory on final exams, and it is where, last August, 34 contestants gathered at the World Memory Championships to be examined in an entirely different manner.
In timed trials, contestants were challenged to took at and then recite a two-page poem, memorize rows of 40-digit numbers, recall the names of 110 people after looking at their photographs, and perform seven other feats of extraordinary retention. Some tests took just a few minutes; others lasted hours. In the 14 years since the World Memory Championships was founded, no one has memorized the order of a shuffled deck of playing cards in less than 30 seconds. That nice round number has become the four-minute mile of competitive memory, a benchmark that the world’s best “mental athletes,” as some of them like to be called are closing in on. Most contestants claim to have just average memories, and scientific testing confirms that they’re not just being modest. Their feats are based on tricks that capitalize on how the human brain encodes information. Anyone can learn them.
Psychologists Elizabeth Valentine and John Wilding, authors of the monograph Superior Memory, recently teamed up with Eleanor Maguire, a neuroscientist at University College London to study eight people, including Karsten, who had finished near the top of the World Memory Championships. They wondered if the contestants’ brains were different in some way. The researchers put the competitors and a group of control subjects into an MRI machine and asked them to perform several different memory tests while their brains were being scanned When it came to memorizing sequences of three-digit numbers, the difference between the memory contestants and the control subjects was, as expected immense. However, when they were show photographs of magnified snowflakes, images that the competitors had never tried to memorize before, the champions did no better than the control group. When the researchers analyzed the brain scans, they found that the memory champs were activating some brain regions that were different from those the control subjects were using. These regions, which included the right posterior hippocampus, are known to be involved in visual memory and spatial navigation.
It might seem odd that the memory contestants would use visual imagery and spatial navigation to remember numbers, but the activity makes sense when their techniques are revealed Cooke, a 23-year-old cognitive-science graduate student with a shoulder-length mop of curly hair, is a grand master of brain storage. He can memorize the order of 10 decks of playing cards in less than an hour or one deck of cards in less than a minute. He is closing in on the 30-second deck. In the Lamb and Flag, Cooke pulled out a deck of cards and shuffled it. He held up three cards—the 7 of spades, the queen of clubs, and the 10 of spades. He pointed at a fireplace and said “Destiny’s Child is whacking Franz Schubert with handbags.” The next three cards were the king of hearts, the king of spades, and the jack of clubs.
How did he do it? Cooke has already memorized a specific person, verb, and object that he associates with each card in the deck. For example, for the 7 of spades, the person (or, in this case, persons) is always the singing group Destiny’s Child the action is surviving a storm, and the image is a dinghy. The queen of clubs is always his friend Henrietta, the action is thwacking with a handbag, and the image is of wardrobes filled with designer clothes. When Cooke commits a deck to memory, he does it three cards at a time. Every three-card group forms a single image of a person doing something to an object. The first card in the triplet becomes the person, the second the verb, the third the object. He then places those images along a specific familiar route, such as the one he took through the Lamb and Flag. In competitions, he uses an imaginary route that he has designed to be as smooth and downhill as possible. When it comes time to recall Cooke takes a mental walk along his route and translates the images into cards. That’s why the MRIs of the memory contestants showed activation in the brain areas associated with visual imagery and spatial navigation.
The more resonant the images are, the more difficult they are to forget. But even meaningful information is hard to remember when there’s a lot of it. That’s why competitive memorizers place their images along an imaginary route. That technique, known as the toci method reportedly originated in 477 B.C. with the Greek poet Simonides of Ceos. Simonides was the sole survivor of a roof collapse that killed all the other guests at a royal banquet. The bodies were mangled beyond recognition, but Simonides was able to reconstruct the guest list by closing his eyes and recalling each individual around the dinner table. What he had discovered was that our brains are exceptionally good at remembering images and spatial information. Evolutionary psychologists have offered an explanation: Presumably our ancestors found it important to recall where they found their last meal or the way back to the cave. After Simonides’ discovery, the loci method became popular across ancient Greece as a trick for memorizing speeches and texts. Aristotle wrote about it, and later a number of treatises on the art of memory were published in Rome. Before printed books, the art of memory was considered a staple of classical education, on a par with grammar, logic, and rhetoric.
The most famous of the naturals was the Russian journalist S. V. Shereshevski, who could recall long lists of numbers memorized decades earlier, as well as poems, strings of nonsense syllables, and just about anything else he was asked to remember. “The capacity of his memory had no distinct limits,” wrote Alexander Luria, the Russian psychologist who studied Shereshevski from the 1920s to the 1950s. Shereshevski also had synesthesia, a rare condition in which the senses become intertwined For example, every number may be associated with a color or every word with a taste. Synesthetic reactions evoke a response in more areas of the brain, making memory easier.
K. Anders Ericsson, a Swedish-born psychologist at Florida State University, thinks anyone can acquire Shereshevski’s skills. He cites an experiment with S. F., an undergraduate who was paid to take a standard test of memory called the digit span for one hour a day, two or three days a week. When he started, he could hold, like most people, only about seven digits in his head at any given time (conveniently, the length of a phone number). Over two years, S. F. completed 250 hours of testing. By then, he had stretched his digit span from 7 to more than 80. The study of S. F. led Ericsson to believe that innately superior memory doesn’t exist at alL When he reviewed original case studies of naturals, he found that exceptional memorizers were using techniques—sometimes without realizing it—and lots of practice. Often, exceptional memory was only for a single type of material, like digits. “If we look at some of these memory tasks, they’re the kind of thing most people don’t even waste one hour practicing, but if they wasted 50 hours, they’d be exceptional at it,” Ericsson says. It would be remarkable, he adds, to find a “person who is exceptional across a number of tasks. I don’t think that there’s any compelling evidence that there are such people.”
The reading Passage has seven paragraphs A-G.
Which paragraph contains the following information? Write the correct letter A-G, in boxes 27-30 on your answer sheet.
27 The reason why competence of super memory is significant in academic settings
28 Mention of a contest for extraordinary memory held in consecutive years
29 An demonstrative example of extraordinary person did an unusual recalling game
30 A belief that extraordinary memory can be gained though enough practice
31 A depiction of rare ability which assist the extraordinary memory reactions
Complete the following summary of the paragraphs of Reading Passage, using no more than three words from the Reading Passage for each answer. Write your answers in boxes 32-36 on your answer sheet.
Using visual imagery and spatial navigation to remember numbers are investigated and explained. A man called Ed Cooke in a pub, spoke a string of odd words when he held 7 of the spades (the first one of the any cards group) was remembered as he encoded it to a 32________ and the card deck to memory are set to be one time of a order of 33 ________; When it comes time to recall, Cooke took a 34 ________along his way and interpreted the imaginary scene into cards. This superior memory skill can be traced back to Ancient Greece, the strategy was called 35 ________which had been an major subject was in ancient 36________ .
Choose TWO correct letter, A-E
Write your answers in boxes 37-38 on your answer sheet.
According to World Memory Championships, what activities need good memory?
A order for a large group of each digit
B recall people’s face
C resemble a long Greek poem
D match name with pictures and features E recall what people ate and did yesterday
Choose TWO correct letter, A-E
Write your answers in boxes 39-40 on your answer sheet.
What is the result of Psychologists Elizabeth Valentine and John Wilding‘s MRI Scan experiment find out?
A the champions ‘ brains is different in some way from common people
B difference in brain of champions’ scan image to control subjects are shown when memorizing sequences of three-digit numbers
C champions did much worse when they are asked to remember photographs
D the memory-champs activated more brain regions than control subjects
E there is some part in the brain coping with visual and spatial memory
|33||Three cards/ 3 cards||34||Mental walk||35||Loci method|
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