READING PASSAGE 1
You should spend about 20 minutes on Questions 1-13 which are based on Reading Passage 1 below.
Insects and Inspired Artificial Robots
The creation of artificial devices with life-like characteristics has been pursued for over 2,000 years, beginning, as did so many things in our modern world, in Ancient Greece. For example, among the inventions of Hero of Alexandria were a windmill-operated pipe organ and a mechanical theatrical play.
With the raise of cybernetic approaches in the late 1940s and early 1950s. A wide variety of electromechanical machines designed to mimic biological processes and systems were constructed. Perhaps the best-known and most directly relevant to biorobotics is W. Gray Walters’ robotic “tortoises” Elsie and Elmer. Walters was a physiologist who made important early contributions to electroencephalography and clinical neurophysiology. His tortoises were small mobile robots covered by a hard shell. The robots were driven by steerable motorized wheels and possessed a headlight, a light sensor, and a touch sensor that responded when the shell was hit. Their behavior was controlled by electronic circuit analogues of neural circuits. The behavioral repertoire of the tortoises included exploration, both positive and negative phototropism, and obstacle avoidance. The activation of these different behaviors in interaction with the robots’ environment could produce a variety of behavioral sequences. Although originally designed to explore Walters’ theories of brain function, the tortoises became objects of popular fascination in much the same way that ancient automata did.
The seeds of the modern renaissance of biorobotics were sown from the mid 1980s to mid 1990s. A key event in this resurgence was Rodney Brooks’ work on behavior-based robots. Although not as directly based on biology as later work would be, Brooks argues that nontrivial and flexible behavior in a robot could be generated by the interaction between simple control machinery and its environment, demonstrating his point with robots accomplishing such tasks as insect-like walking. Another important milestone was Raibert’s work on hopping and legged robots, which emphasized the central role of energetics in the dynamic balance and locomotion of animals. Based on studies of serpentine motion, Hirose developed a number of snake-like locomotors and manipulators. In the early 1990s, Beer, Quinn, Chiel & Ritzmann developed a series of hexapod robots based directly on cockroach and stick insect body morphology and neural control. Early biorobotic work on the sensory side includes Franceshini’s robotic compound eye based on studies of insect eyes and motion-sensitive neurons in the fly, Webb’s robotic model of cricket phonotaxis and Grasso et al’s robotic model of lobster chemical orientation strategies. An early example of robots whose control was based on theories of human brain function is given by the work of Edelman et al.
There has been an explosion of work in biorobotics in recent years, with robotic vocal tracts, jaws, retinas, expressive faces, hands, arms, legs, etc. deployed on robotic worms, snakes, ants, flies, crickets, cockroaches, walking stick insects, dinosaurs, bats, lobsters, tuna, pickerel, turkeys, apes and humanoids. Thus, no brief survey could possibly do justice to the range of work being undertaken.
A recent example of biologically-inspired robotics is Spenko et al’s work on a hexapedal robotic climber called RiSE. In order to grip a vertical surface, this robot combines both bonding mechanisms inspired by the structure of gecko feet and interlocking mechanisms inspired by the structure of insect spines and claws. In addition, its design is based on a set of principles that have been found to be common to many climbing animals: a sprawled posture keeps the body close to the surface so as to reduce the pitch-back moment; front limbs pull inward and rear limbs push outward so as to counteract the pitch-back moment; a long body reduces the pull-in force required of the front limbs; lateral forces act inward toward the central axis of the body; complaint legs, ankles and toes so as to distribute contact forces. Each of the six legs of RiSE have two degrees of freedom and the robot also possesses s static tail that presses against the surface to reduce the pull-in forces required of the front legs. The robot uses a wave gait in which only one leg at a time is lifted from the surface. In addition to an open-loop gait generator, RiSE utilizes a variety of feedback controllers, including traction force control, normal force control and gait regulation. In addition, the robot has a pawing behavior that allows a foot that fails to grasp on initial contact to reestablish a grip on the climbing surface. Spenko et al have demonstrated that RiSE is able to traverse a variety of horizontal and vertical surfaces, including climbing trees and brick or cinder block walls.
A powerful example of biorobotic modeling is provided by the aerodynamics of insect flight. Although quasi-steady-state aerodynamical analyses of the sort used to understand aircraft have been successfully applied to larger animals, they have not been very successful for explaining the generation of lift in small flying insects due to the tiny wingspans, relatively slow flight speeds and extremely fast wing movements involved. However, a recent biorobotic model by Dickinson and colleagues has begun to shed considerable light on the unsteady aerodynamics insect flight. Because of the delicate size and high speed of insect wings, direct measurement of the forces involved is extremely difficult. For this reason, a robotic model with a 60 cm wingspan was used to explore the non-steady-state airflow during hovering by the fruit fly Drosophila melanogaster. In order to reproduce the Reynolds number relevant to small insects flying in air, their model was submerged in mineral oil and scaled both in space and time. Force sensors at the base of one wing allowed direct measurement of the forces produced and illumination of air bubbles in the tank allowed direct observation of the fluid flow around the robotic wings. Dickinson and colleagues found that three major mechanisms contributed to lift generation in the model. First, vortices formed at the leading edge of the wing produce lift during much of the power stroke. Second, additional lift is produced by circulation of air around the wings due to rapid rotation at the beginning and end of each stroke. Third, further forces are produces at the start of each upstroke and downstroke due to collisions of the wings with the swirling wake produced by the previous stroke, a mechanism termed wake capture. Due to the sensitivity of these latter two mechanisms to the timing of wing rotation, the model suggests that the control of small details of wing motion can be used in steering flight.
Choose the most suitable headings for paragraphs A-F from the list of heading below.
Write appropriate number (i-x) in boxes 1-6 on your answer sheet.
NB There are more headings than paragraphs, so you will not use them all.
List of Headings
i A biorobotic model exploring insect flight
ii Modern practices of artificial device usage
iii Robotic climber better than gecko
iv Insect fight inspires the applications of steering operation
v Prosperity of biorobot family
vi The revival of modern biorobotics
vii Combine machines and environment
viii The advent of robots and their effects on modern society
ix The most famous biorobot in early days
x Bionics device is not a modern conception
1 Paragraph A
2 Paragraph B
3 Paragraph C
4 Paragraph D
5 Paragraph E
6 Paragraph F
Use the information in the passage to match the people (listed A-E) with opinions or deeds (listed 7-11) below.
Write the appropriate letters A-E in boxes 7-11 on your answer sheet.
NB Some people may match more than one discovery.
A W. Gray Walters
B Rodney Brooks
C Michael Dickinson
D Spenko et al
E Edelman et al
7 _________ made contributions to neurophysiology.
8 _________ endowed robots with agility from the innovation of machinery environmental fit.
9 _________ generated mechanical intelligence inspired by the way human brain works
10 _________ modified mechanical models based on the structure of insects.
11 _________ found the mechanism of insect flight
Choose words from the passage to answer the questions 12-13, writing NO MORE THAN THREE WORDS for each blank.
12 What plays the most critical role in Raibert’s hopping and legged robots?
13 What allowed direct measurement of the lifting forces of the biorobotic model?
READING PASSAGE 2
You should spend about 20 minutes on Questions 14-26 which are based on Reading Passage 2 below.
Extinction of Aussie Animals
World Wildlife Fund Australia has revealed its list of extinct wildlife to coincide with Australia Day. The list covers a wide range of species, from birds to reptiles, marsupials, insects and even flowers. Top of the list is the green and gold frog which has had its home decimated by drought.” Many Aussie spices need our help in order to survive,” WWF threatened species program manager Kat Miller said. “Without knowing the reason many had disappeared for, we will risk losing another 346 animal and 1249 plant species listed as threatened under federal legislation. Australia has the one of the worst record of mammal extinction in the world”. WWF Australia said 9 percent of birds, 7 percent of reptiles and 16 percent of amphibians are extinct since early human settlement.
The conservation group said half the mammals that have become extinct globally in the last 200 years have been Australian species. Ancient hunters and gatherers may have triggered the failure of the annual Australian Monsoon some 12,000 years ago by burning massive tracts of the country’s interior, resulting in the desertification that is evident today, says a new study. Researcher Gifford Miller of the University of Colorado at Boulder said the new study builds on his research group’s previous findings that dozens of giant animal species became extinct in Australia 50,000 years ago due to ecosystem changes caused by human burning. This study, appearing in Geology, indicates such burning may have altered the flora enough to decrease the exchange of water vapor between the biosphere and atmosphere, causing the failure of the Australian Monsoon over the interior.
“The question is whether localized burning 50,000 years ago could have had a continental-scale effect,” said Miller. “The implications are that the burning practices of early humans may have changed the climate of the Australian continent by weakening the penetration of monsoon moisture into the interior”. A paper on the subject by Miller appears in the January issue of Geology. Co-authors include CU Boulder’s Jennifer Mangan, David Pollard, Starley Thompson and Benjamin Felzer of the National Center for Atmospheric Research in Boulder and John Magee of Australian National University in Canberra.
Geologic evidence indicates the interior of Australia was much wetter about 125,000 years ago during the last interglacial period. Although planetary and meteorological conditions during the most recent ice age caused Earth’s major monsoons to waver, all except the Australian Monsoon were “reinvigorated” to full force during the Holocene Period beginning about 12,000 years ago, he said. Although the Australian Monsoon delivers about 39 inches of rain annually to the north coast as it moves south from Asia, only about 13 inches of rain now falls on the continent’s interior each year, said Miller. Lake Eyre, a deep-water lake in the continent’s interior that was filled by regular monsoon rains about 60,000 years ago, is now a huge salt flat that is occasionally covered by a thin layer of salty water.
The earliest human colonizers are believed to have arrived in Australia by sea from Indonesia about 50,000 years ago, using fire as a tool to hunt, clear paths, signal each other and promote the growth of certain plants, he said. Fossil remains of browse-dependent birds and marsupials indicate the interior was made up of trees, shrubs and grasses rather than the desert scrub environment present today.
The researchers used global climate model simulations to evaluate the atmospheric and meteorological conditions in Australia over time, as well as the sensitivity of the monsoon to different vegetation and soil types. A climate model simulating a forested Australia produced twice as much annual monsoon precipitation over the continental interior as the model simulating arid scrub conditions, he said.
“Systematic burning across the semiarid zone, where nutrients are the lowest of any continental region, may have been responsible for the rapid transformation of a drought-tolerant ecosystem high in broad-leaf species to the modern desert scrub,” he said. “In the process, vegetation feedbacks promoting the penetration of monsoon moisture into the continental interior would have been disrupted”. More than 85 percent of Australia’s mega fauna weighing more than 100 pounds went extinct roughly 50,000 years ago, including an ostrich-sized bird, 19 species of marsupials, a 25-foot-long lizard and a Volkswagen-sized tortoise, he said.
Evidence for burning includes increased charcoal deposits preserved in lake sediments at the boundary between rainforest and interior desert beginning about 50,000 years ago, Miller said. In addition, a number of rainforest gymnosperms – plants whose seeds are not encased and protected and are therefore more vulnerable to fire –went extinct at about that time. Natural fires resulting from summer lightning strikes have played an integral part in the ecology of Australia’s interior, and many plant species are adapted to regimes of frequent fires, he said. “But the systematic burning of the interior by the earliest colonizers differed enough from the natural fire cycle that key ecosystems may have been pushed past a threshold from which they could not recover.”
Reading Passage 2 contains 8 paragraphs A –H.
Which paragraphs state the following information?
Write the appropriate letters A-H in boxes 14-16 on your answer sheet.
14 Why did an interior Australian lake change to a dry flat?
15 When did an ostrich-sized bird go extinct?
16 Why did the ancient settlers in Australia burn the forests?
Choose ONE phrase from the list of phrases A-G below to complete each of the sentences 17-20 below.
Write the appropriate letters (A-G) in boxes 17-20 on your answer sheet.
17 Ancient hunters and gatherers
18 January issue of Geology
19 Fossil remains
20 A climate model
A _________ caused the failure of the annual Australian Monsoon by burning tracts.
B _________ were responsible for the distinction of an Australian giant animal species because of their massive hunting.
C _________ showed that in the past the interior of Australia was not a desert.
D _________ altered the flora to decrease the exchange of water vapor between the biosphere and atmosphere.
E _________ suggested that the changed climate of the Australian continent was led by the weakened penetration of monsoon moisture into the interior.
F _________ indicated that the forests facilitated more rainfall.
G _________ indicated that the extinction of an Australian species resulted from changes in the local ecosystem.
Do the following statements agree with the claims of the writer in Reading Passage 2?
On your answer sheet please write
TRUE if the statement is true
FALSE if the statement is false
NOT GIVEN if the information is not given in the passage.
21 According to the WWF, Australia has the worst record of animal extinction in the world.
22 In Australia, hundreds of endangered animals and plants species will keep disappearing.
23 The distinction of Australian giant animals was a knock-on effect after human burning ceased the monsoon.
24 Lake Eyre has always been filled with salty water.
25 It is a theoretic assumption that early humans burned massive tracts in Australia.
26 Varieties of plants from Australia’s interior have now adapted to recurrent fires.
READING PASSAGE 3
You should spend about 20 minutes on Questions 27-40 which are based on Reading Passage 3 below.
From the results of an annual Alaskan betting contest to sightings of migratory birds, ecologists are using a wealth of unusual data to predict the impact of climate change.
Tim Sparks slides a small leather-bound notebook out of an envelope. The book’s yellowing pages contain bee-keeping notes made between 1941 and 1969 by the late Walter Coates of Kilworth, Leicestershire. He adds it to his growing pile of local journals, birdwatchers’ lists and gardening diaries. “We’re uncovering about one major new record each month,” he says, “I still get surprised.” Around two centuries before Coates, Robert Marsham, a landowner from Norfolk in the east of England, began recording the life cycles of plants and animals on his estate – when the first wood anemones flowered, the dates on which the oaks burst into leaf and the rooks began nesting. Successive Marshams continued compiling these notes for 211 years.
Today, such records are being put to uses that their authors could not possibly have expected. These data sets, and others like them, are proving invaluable to ecologists interested in the timing of biological events, or phenology. By combining the records with climate data, researchers can reveal how, for example, changes in temperature affect the arrival of spring, allowing ecologists to make improved predictions about the impact of climate change. A small band of researchers is combing through hundreds of years of records taken by thousands of amateur naturalists. And more systematic projects have also started up, producing an overwhelming response. “The amount of interest is almost frightening,” says Sparks, a climate researcher at the Centre for Ecology and Hydrology in Monks Wood, Cambridgeshire.
Sparks first became aware of the army of “closet phenologists”, as he describes them, when a retiring colleague gave him the Marsham records. He now spends much of his time following leads from one historical data set to another. As news of his quest spreads, people tip him off to other historical records, and more amateur phenologists come out of their closets. The British devotion to recording and collecting makes his job easier – one man from Kent sent him 30 years’ worth of kitchen calendars, on which he had noted the date that his neighbour’s magnolia tree flowered.
Other researchers have unearthed data from equally odd sources. Rafe Sagarin, an ecologist at Stanford University in California, recently studied records of a betting contest in which participants attempt to guess the exact time at which a specially erected wooden tripod will fall through the surface of a thawing river. The competition has taken place annually on the Tenana River in Alaska since 1917, and analysis of the results showed that the thaw now arrives five days earlier than it did when the contest began.
Overall, such records have helped to show that, compared with 20 years ago, a raft of natural events now occur earlier across much of the northern hemisphere, from the opening of leaves to the return of birds from migration and the emergence of butterflies from hibernation. The data can also hint at how nature will change in the future. Together with models of climate change, amateurs’ records could help guide conservation. Terry Root, an ecologist at the University of Michigan in Ann Arbor, has collected birdwatchers’ counts of wildfowl taken between 1955 and 1996 on seasonal ponds in the American Midwest and combined them with climate data and models of future warming. Her analysis shows that the increased droughts that the models predict could halve the breeding populations at the ponds. “The number of waterfowl in North America will most probably drop significantly with global warming,” she says.
But not all professionals are happy to use amateur data. “A lot of scientists won’t touch them, they say they’re too full of problems,” says Root. Because different observers can have different ideas of what constitutes, for example, an open snowdrop. “The biggest concern with ad hoc observations is how carefully and systematically they were taken,” says Mark Schwartz of the University of Wisconsin, Milwaukee, who studies the interactions between plants and climate. “We need to know pretty precisely what a person’s been observing – if they just say ‘I noted when the leaves came out’, it might not be that useful.” Measuring the onset of autumn can be particularly problematic because deciding when leaves change colour is a more subjective process than noting when they appear.
Overall, most phenologists are positive about the contribution that amateurs can make. “They get at the raw power of science: careful observation of the natural world,” says Sagarin. But the professionals also acknowledge the need for careful quality control. Root, for example, tries to gauge the quality of an amateur archive by interviewing its collector. “You always have to worry – things as trivial as vacations can affect measurement. I disregard a lot of records because they’re not rigorous enough,” she says. Others suggest that the right statistics can iron out some of the problems with amateur data. Together with colleagues at Wageningen University in the Netherlands, environmental scientist Arnold van Vliet is developing statistical techniques to account for the uncertainty in amateur phenological data. With the enthusiasm of amateur phenologists evident from past records, professional researchers are now trying to create standardised recording schemes for future efforts. They hope that well-designed studies will generate a volume of observations large enough to drown out the idiosyncrasies of individual recorders. The data are cheap to collect, and can provide breadth in space, time and range of species. “It’s very difficult to collect data on a large geographical scale without enlisting an army of observers,” says Root.
Phenology also helps to drive home messages about climate change. “Because the public understand these records, they accept them,” says Sparks. It can also illustrate potentially unpleasant consequences, he adds, such as the finding that more rat infestations are reported to local councils in warmer years. And getting people involved is great for public relations. “People are thrilled to think that the data they’ve been collecting as a hobby can be used for something scientific – it empowers them,” says Root.
Reading Passage 3 has eight paragraphs A-H.
Which paragraph contains the following information?
Write the correct letter A-H in boxes 27-33 on your answer sheet.
27 The definition of phenology
28 How Sparks first became aware of amateur records
29 How people reacted to their involvement in data collection
30 The necessity to encourage amateur data collection
31 A description of using amateur records to make predictions
32 Records of a competition providing clues to climate change
33 A description of a very old record compiled by generations of amateur naturalists
Complete the sentences below with NO MORE THAN TWO WORDS from the passage for each answer.
Write your answers in boxes 34-36 on your answer sheet.
34 Walter Coates’s records largely contain the information of ________.
35 Robert Marsham is famous for recording the ________ of animals and plants on his land.
36 According to some phenologists, global warming may cause the number of waterfowl in North America to drop significantly due to increased ________.
Choose the correct letter A, B, C or D.
Write your answers in boxes 37-40 on your answer sheet.
37 Why do a lot of scientists discredit the data collected by amateurs?
A Scientific methods were not used in data collection.
B Amateur observers are not careful in recording their data.
C Amateur data is not reliable.
D Amateur data is produced by wrong candidates.
38 Mark Schwartz used the example of leaves to illustrate that
A amateur records can’t be used.
B amateur records are always unsystematic.
C the colour change of leaves is hard to observe.
D valuable information is often precise.
39 How do the scientists suggest amateur data should be used?
A Using improved methods
B Being more careful in observation
C Using raw materials
D Applying statistical techniques in data collection
40 What’s the implication of phenology for ordinary people?
A It empowers the public.
B It promotes public relations.
C It warns people of animal infestation.
D It raises awareness about climate change in the public.
13. Force sensors
21. NOT GIVEN
22. NOT GIVEN
35 life cycles