Origin of Species & Continent Formation
THE FACT THAT there was once a Pangean supercontinent, a Panthalassa Ocean, and a Tethys Ocean, has profound implications for the evolution of multicellular life on Earth. These considerations were unknown to the scientists of the 19th century — making their scientific deductions even more remarkable. Quite independently of each other, Charles Darwin and his young contemporary Alfred Russel Wallace reached the conclusion that life had evolved by natural selection. Wallace later wrote in My Life of his own inspiration:
Why do some species die and some live? The answer was clearly that on the whole the best fitted lived. From the effects of disease the most healthy escaped; from enemies the strongest, the swiftest or the most cunning from famine the best hunters ... then it suddenly flashed on me that this self-acting process would improve the race, because in every generation the inferior would inevitably be killed off and the superior would remain, that is , the fittest would survive.
Both Darwin's and Wallace's ideas about natural selection had been influenced by the essays of Thomas Malthus in his Principles of Population. Their conclusions, however, had been the direct result of their personal observation of animals and plants in widely separated geographic locations: Darwin from his experiences during the voyage of the Beagle, and particularly during the ship's visit to the Galapagos Islands in the East Pacific in 1835: Wallace during his years of travel in the Amazon Basin and in the Indonesia-Australian Archipelago in the 1850s.
Darwin had been documenting his ideas on natural selection for many years when he received a paper on this selfsame subject from Wallace, who asked for Darwin's opinion and help in getting it published. In July 1858, Charles Lyell and J. D Hooker, close friends of Darwin, pressed Darwin to present his conclusions so that he would not lose priority to and unknown naturalist. Presiding over the hastily called but now historic meeting of the Linnean Society in London, Lyell and Hooker explained to the distinguished members how "these two gentlemen" (who were absent: Wallace was abroad and Darwin chose not to attend), had "independently and unknown to one another, comceived the same very ingenious theory.”
Both Darwin and Wallace had realized that the anomalous distribution of species in particular regions had profound evolutionary significance. Subsequently, Darwin spent the rest of his days in almost total seclusion thinking and writing mainly about the origin of species. In constrast, Wallace applied himself to the science of biogeography, the study of the pattern and distribution of species, and its significance, resulting in the publication of a massive two-volume work the Geographical Distribution of Animals in 1876.
Wallace was a gentle and modest man, but also persistent and quietly courageous. He spent years working in the most arduous possible climates and terrains, particularly in the Malay archipelago, he made patient and detailed zoological observations and collected huge number of speciments for museums and collectors-which is how he made a living. One result of his work was the conclusion that there is a distinct faunal boundary, called "Wallace's line, "between an Asian realm of animals in Java, Borneo and the Philipiones and an Australian realm in New Guinea and Australia. In essence this boundary posed a difficult question: How on Earth did plants and animals with a clear affinity to the Northern Hemisphere meet with their Southern Hemispheric counterparts along such a distinct Malaysian demarcation zone? Wallace was uncertain about demarcation on one particular island- Celebes, a curiously shaped place that is midway between the two groups. Initially he assigned its flora-fauna to the Australian side of the line, but later he transferred it to the Asian side. Today we know the reason for his dilemma. 200MYA East and West Celebes were islands with their own natural history lying on opposite sides of the Tethys Ocean. They did not collide until about 15 MYA. The answer to the main question is that Wallace's Line categorizes Laurasia-derived flora-fauna (the Asian) and Gondwana-derived flora-fauna (the Australian), fauna that had evolved on opposing shares of the Tethys. The closure of the Tethys Ocean today is manifested by the ongoing collision of Australia/New Guinea with Indochina/Indonesia and the continuing closure of the Mediterranean Sea—a remnant of the Western Tethys Ocean.
IN HIS ORIGIN OF CONTINENTS AND OCEANS, Wegener quoted at length from Wallace’s Geographical Distribution of Animals. According to Wegener's reading, Wallace had identified three clear divisions of Australian animals, which supported his own theory of continental displacement. Wallace had shown that animals long established in southwestern Australia had an affinity with animals in South Africa, Madagascar, India, and Ceylon, but did not have an affinity with those in Asia. Wallace also showed that Australian marsupials and monotremes are clearly related to those in South America, the Moluccas, and various Pacific islands, and that none are found in neighboring Indonesia. From this and related data, Wegener concluded that the then broadly accepted "landbridge" theory could not account for this distribution of animals and that only his theory of continental drift could explain it.
The theory that Wegener dismissed in preference to his own proposed that plants and animals had once migrated across now-submerged intercontinental landbridges. In 1885, one of Europe's leading geologists, Eduard Suess, theorized that as the rigid Earth cools, its upper crust shrinks and wrinkles like the withering skin of an aging apple. He suggested that the planet's seas and oceans now fill the wrinkles between once-contiguous plateaus.
Today, we know that we live on a dynamic Earth with shifting, colliding and separating tectonic plates, not a "withering skin", and the main debate in the field of biogeography has shifted. The discussion now concerns "dispersalism" versus "vicarianism": unrestricted radiation of species on the one hand and the development of barriers to migration on the other. Dispersion is a short-term phenomenon—the daily or seasonal migration of species and their radiation to the limits of their natural environment on an extensive and continuous landmass. Vicarian evolution, however, depends upon the separation and isolation of a variety of species within the confines of natural barriers in the form of islands, lakes, or shallow seas—topographical features that take a long time to develop.
Use the information in the passage to match the people (listed A-E) with opinions or deeds below. Write the appropriate letters A-E in boxes 1-5 on your answer sheet.
C Darwin and Wallace
E Lyell and Hooker
1 urged Darwin to publish his scientific findings
2 Depicted physical feature of earth's crust.
3 believed in continental drift theory while rejecting another one
4 Published works about wildlife distribution in different region.
5 Evolution of species is based on selection by nature.
The reading Passage has nine paragraphs A-l.
Which paragraph contains the following information?
Write the correct letter A-l, in boxes 6-8 on your answer sheet.
6 Best adaptable animal survived on the planet.
7 Boundary called Wallace's line found between Asia and Australia.
8 Animal relevance exists between Australia and Africa.
Complete the following summary of the paragraphs of Reading Passage, using no more than two words from the Reading Passage for each answer. Write your answers in boxes 9-13 on your answer sheet.
Wegener found that continental drift instead of “land bridge” theory could explain strange species' distribution phenomenon. In his theory, vegetation and wildlife 9___ intercontinentally. However, Eduard Suess compared the wrinkle of crust to 10___ of an old apple. Now it is well known that we are living on the planet where there are 11___ in constant mobile states instead of what Suess described Hot spot in biogeography are switched to concerns between two terms: “12___” and “13___”
1 E 2 A 3 D
4 B 5 C 6 B
7 F 8 G 9 migrated
10 withering skin 11 (tectonic) plates 12 dispersalism
Man or Machine
During July 2003, the Museum of Science in Cambridge, Massachusetts exhibited what Honda calls 'the world's most advanced humanoid robot', ASIMO (the Advanced Step in Innovative Mobility). Honda's brainchild is on tour in North America and delighting audiences wherever it goes. After 17 years in the making, ASIMO stands at four feet tall, weighs around 115 pounds and looks like a child in an astronaut's suit. Though it is difficult to see ASIMO's face at a distance, on closer inspection it has a smile and two large 'eyes' that conceal cameras. The robot cannot work autonomously - its actions are 'remote controlled' by scientists through the computer in its backpack (n.背包,背囊). Yet watching ASMIO perform at a show in Massachusetts it seemed uncannily human. The audience cheered as ASIMO walked forwards and backwards, side to side and up and downstairs. After the show, a number of people told me that they would like robots to play more of a role in daily life - one even said that the robot would be like 'another person'.
While the Japanese have made huge strides in solving some of the engineering problems of human kinetics (n.动力学) and bipedal (adj.两足动物的) movements, for the past 10 years scientists at MIT’s former Artificial Intelligence (AI) lab (recently renamed the Computer Science and Artificial Intelligence Laboratory, CSAIL) have been making robots that can behave like humans and interact with humans. One of MIT’s robots, Kismet, is an anthropomorphic (adj.拟人的) head and has two eyes (complete with eyelids), ears, a mouth, and eyebrows. It has several facial expressions, including happy, sad, frightened and disgusted. Human interlocutors are able to read some of the robot's facial expressions, and often change their behavior towards the machine as a result - for example, playing with it when it appears 'sad'. Kismet is now in MIT's museum, but the ideas developed here continue to be explored in new robots.
Cog (short for Cognition) is another pioneering project from MIT's former AI lab. Cog has a head, eyes, two arms, hands and a torso (n.躯干) - and its proportions were originally measured from the body of a researcher in the lab. The work on Cog has been used to test theories of embodiment and developmental robotics, particularly getting a robot to develop intelligence by responding to its environment via sensors, and to learn through these types of interactions.
MIT is getting furthest down the road to creating human-like and interactive robots. Some scientists argue that ASIMO is a great engineering feat but not an intelligent machine - because it is unable to interact autonomously with unpredictabilities in its environment in meaningful ways, and learn from experience. Robots like Cog and Kismet and new robots at MIT's CSAIL and media lab, however, are beginning to do this.
These are exciting developments. Creating a machine that can walk, make gestures and learn from its environment is an amazing achievement. And watch this space: these achievements are likely rapidly to be improved upon. Humanoid robots could have a plethora of uses in society, helping to free people from everyday tasks. In Japan, for example, there is an aim to create robots that can do the tasks similar to an average human, and also act in more sophisticated situations as firefighters, astronauts or medical assistants to the elderly in the workplace and in homes - partly in order to counterbalance the effects of an ageing population.
Such robots say much about the way in which we view humanity, and they bring out the best and worst of us. On one hand, these developments express human creativity - our ability to invent, experiment, and to extend our control over the world. On the other hand, the aim to create a robot like a human being is spurred on by dehumanized ideas - by the sense that human companionship can be substituted by machines; that humans lose their humanity when they interact with technology; or that we are little more than surface and ritual behaviors, that can be simulated with metal and electrical circuits.
Reading passage 1 has six paragraphs, A-F.
Which paragraph contains the following information?
Write the correct letter, A-F, in boxes 1 -6 on your answer sheet.
NB you may use any letter more than once
1 different ways of using robots
2 a robot whose body has the same proportion as that of an adult
3 the fact that human can be copied and replaced by robots
4 a comparison between ASIMO from Honda and other robots
5 the pros and cons of creating robots
6 a robot that has eyebrows
Complete the following summary of the paragraphs of Reading Passage 1, using NO MORE THAN TWO WORDS from the Reading Passage for each answer.
Write your answers in boxes 7-13 on your answer sheet.
In 2003, Massachusetts displayed a robot named ASIMO which was invented by Honda, after a period of 7.............. in the making. The operating information is stored in the computer in its 8.............. so that scientists can control ASIMO's movement. While Japan is making great progress, MIT is developing robots that are human-like and can 9.............. humans. What is special about Kismet is that it has different 10.............. which can be read by human interlocutors. 11.............. is another robot from MIT, whose body's proportion is the same as an adult. By responding to the surroundings through 12.............., it could develop its 13..............
1 E 2 C 3 F
4 D 5 F 6 B
7 17 years 8 backpack 9 interact with
10 facial expressions 11 Cog/Cognition 12 sensors
Reclaiming the Future of Aral Sea
The Aral Sea gets almost all its water from the Amu and Syr rivers. Over millennium the Amu's course has drifted away from the sea, causing it to shrink. But the lake always rebounded as the Amu shifted back again. Today heavy irrigation for crops such as cotton and rice siphons off much of the two rivers, severely cutting flow into their deltas and thus into the sea. Evaporation vastly outpaces any rainfall, snowmelt or groundwater supply, reducing water volume and raising salinity. The Soviet Union hid the sea's demise for decades until 1985, when leader Mikhail Gorbachev-revealed the great environmental and human tragedy. By the late 1980s the sea's level had dropped so much that the water had separated into two distinct bodies: the Small Aral (north) and the Large Aral (south). By 2007 the south had split into a deep western basin, a shallow eastern basin and a small, isolated gulf. The Large Aral's volume had dropped from 708 to only 75 cubic kilometers (km3), and salinity had risen from 14 to more than 100 grams per liter (g/l). The 1991 dissolution of the Soviet Union divided the lake between newly formed Kazakhstan and Uzbekistan, ending a grand Soviet plan to channel in water from distant Siberian rivers and establishing competition for the dwindling resource.
Desiccation of the Aral Sea has wrought severe consequences. Greatly reduced river flows ended the spring floods that sustained wetlands with freshwater and enriched sediment. Fish species in the lakes dropped from 32 to 6 because of rising salinity and loss of spawning and feeding grounds (most survived in the river deltas). Commercial fisheries, which caught 40,000 metric tons of fish in 1960, were gone by the mid-1980s; more than 60,000 related jobs were lost. The most common remaining lake occupant was the Black Sea flounder, a saltwater fish introduced in the 1970s, but by 2003 it had disappeared from the southern lakes because salinity was more than 70 g/l, double that of a typical ocean. Shipping on the Aral also ceased because the water receded many kilometers from the major ports of Aralsk to the north and Moynak in the south; keeping increasingly long channels open to the cities became too costly. Groundwater levels dropped with falling lake levels, intensifying desertification.
The receding sea has exposed and dried 54.000 square kilometers of seabed, which is choked with salt and in some places laced with pesticides and other agricultural chemicals deposited by runoff from area fanning. Strong windstorms blow salt, dust and contaminants as far as 500 km. Winds from the north and northeast drive the most severe storms, seriously impacting the Amu delta to the south—the most densely settled and most economically and ecologically important area in the region. Airborne sodium bicarbonate, sodium chloride and sodium sulfate kill or retard the growth of natural vegetation and crops—a cruel irony given that irrigating those crops starves the sea. Health experts say the local population suffers from high levels of respiratory illnesses, throat and esophageal cancer, and digestive disorders caused by breathing and ingesting salt-laden air and water. Liver and kidney ailments, as well as eye problems, are common. The loss of fish has also greatly reduced dietary variety, worsening malnutrition and anemia, particularly in pregnant women.
Returning the entire Aral Sea to its 1960s stale is unrealistic. The annual inflow from the Syr and Amu rivers would have to be quadrupled from the recent average of 13 km3. The only means would be to curtail irrigation, which accounts for 92 percent of water withdrawals. Yet four of the five former Soviet republics in the Aral Sea basin (Kazakhstan is the exception) intend to expand irrigation, mainly to feed growing populations. Switching to less water- intensive crops, such as replacing cotton with winter wheat, could help, but the two primary irrigating nations, Uzbekistan and Turkmenistan, intend to keep cotton to earn foreign currency. The extensive irrigation canals could be greatly improved; many are simply cuts through sand, and they allow enormous quantities of water to seep away. Modernizing the entire system could save 12 km3 a year but would cost at least $16 billion. The basin states do not have the money or the political will. Kazakhstan has nonetheless tried to partially restore the northern Aral.
We expect salinities in the Small Aral to settle at three to 14 g/l, depending on location. At these levels many more indigenous species should return, although the saltwater kambala would disappear from most places. Further restoration is possible. For example, if irrigation improvements raised the average annual inflow from the Syr to 4.5 km3, which is entirely feasible, the lake's level could stabilize at about 47 meters. This change would bring the shoreline to within eight kilometers of Aralsk, the former major port city, close enough to allow recovery of an earlier channel that connected the city to the receding waters. The channel would give large commercial fishing vessels access to the sea, and shipping could restart. Marshlands and fish populations would improve even more because of a further reduction in salinity. Outflow to the southern lakes could also increase, helping their restoration. Such a plan would require a much longer and higher dike, as well as reconstruction of the gate facility, and it is not clear that Kazakhstan has the means or desire to pursue it. The country is, however, now discussing more modest proposals to bring water closer to Aralsk.
The Large Aral faces a difficult future; it continues to shrink rapidly. Only a long, narrow channel connects the shallow eastern basin and the deeper western basin, and this could close altogether. If countries along the Amu make no changes, we estimate that at current rates of groundwater in and evaporation out, an isolated eastern basin would stabilize at an area of 4,300 square kilometers (km2). But it would average only 2.5 meters deep. Salinity would exceed 100 g/l, possibly reaching 200 g/l; the only creatures that could live in it would be brine shrimp and bacteria. The western basin's fate depends on ground- water inflow, estimates for which arc uncertain. Someone has noted numerous fresh-water springs on the western cliffs. The most reliable calculations indicate that the basin would settle at about 2,100 km2. The lake would still be relatively deep, reaching 37 meters in spots, but salinity would rise well above 100 g/l.
The reading Passage has seven paragraphs A-F.
Which paragraph contains the following information?
Write the correct letter A-F, in boxes 14-19 on your answer sheet.
NB You may use any letter more than once.
14 A mission impossible
15 An extremely worrying trend for one main part of Aral Sea
16 An uncompleted project because of political reasons
17 A promising recover)' in the future
18 A strongly affected populated district
19 The disclosure of a big secret
Do the following statements agree with the information given in Reading Passage 2?
In boxes 20-22 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
20 In response to the increasingly growing number in the population, not all nations near the Aral Sea consider plans which will enhance the severity of the problems the Aral Sea is faced with.
21 The willingness for Kazakhstan to take the restoration action to save the Small Aral Sea is somehow not certain.
22 The western basin seems to have a destined future regardless of the influx of the groundwater.
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 23-26 on your answer sheet.
The 23................. produced by the flood waters, which were ceased because of the decrease in 24.................. of the Aral Sea, are main sources to keep the survival of the wetlands. The types of fishes living in it experienced a devastating tragedy out of the increase in 25................... and decrease in spots for 26................... with a good example of the extinction of a specific fish. What is more, fisheries and shipping suffered greatly from these vast changes.
14 D 15 F 16 A
17 E 18 C 19 A
20 TRUE 21 TRUE 22 FALSE
23 freshwater and sediment 24 river flows
25 salinity 26 spawning and feeding
The evolutional mystery: Crocodile survives
Crocodiles have been around for 200 million years, but they're certainly not primitive. The early forms of crocodiles are known as Crocodilia. Since they spent most of their life beneath water, accordingly their body adapted to aquatic lifestyle. Due to the changes formed within their body shape and tendency to adapt according to the climate they were able to survive when most of the reptiles of their period are just a part of history. In their tenure on Earth, they've endured the impacts of meteors, planetary refrigeration, extreme upheavals of the Earth's tectonic surface and profound climate change. They were around for the rise and fall of the dinosaurs, and even 65 million years of supposed mammalian dominance has failed to loosen their grip on the environments they inhabit.
The first crocodile-like ancestors appeared about 230 million years ago, with many of the features that make crocs such successful stealth hunters already in place: streamlined body, long tail, protective armour and long jaws. They have long head and a long tail that helps them to change their direction in water while moving. They have four legs which are short and are webbed. Never underestimate their ability to move on ground. When they move they can move at such a speed that won't give you a second chance to make a mistake by going close to them especially when hungry. They can lift their whole body within seconds from ground.
Crocodilians have no lips. When submerged in their classic 'sit and wait' position, their mouths fill with water. The nostrils on the tip of the elongated snout lead into canals that run through bone to open behind the valve - allowing the crocodilian to breathe through its nostrils even though its mouth is under water. When the animal is totally submerged, another valve seals the nostrils, so the crocodilian can open its mouth to catch prey with no fear of drowning. The thin skin on the crocodilian head and face is covered with tiny, pigmented domes, forming a network of neural pressure receptors that can detect barely perceptible vibrations in the water. This enables a crocodile lying in silent darkness to suddenly throw its head sideways and grasp with deadly accuracy small prey moving close by.
Like other reptiles, crocodiles are endothermic animals (cold-blooded, or whose body temperature varies with the temperature of the surrounding environment) and, therefore, need to sunbathe, to raise the temperature of the body. On the contrary, if it is too hot, they prefer being in water or in the shade. Being a cold-blooded species, the crocodilian heart is unique in having an actively controlled valve that can redirect, at will, blood flow away from the lungs and recirculate it around the body, taking oxygen to where it's needed most. In addition, their metabolism is a very slow one, so, they can survive for long periods without feeding. Crocodiles are capable of slowing their metabolism even further allowing them to survive for a full year without feeding.
Crocodiles use a very effective technique to catch the prey. The prey remains almost unaware of the fact that there can be any crocodile beneath water. The crocodile is successful because it switches its feeding methods. It hunts fish, grabs birds at the surface, hides among the water edge vegetation to wait for a gazelle to come by, and when there is a chance for an ambush, the crocodile lunges forward, knocks the animal with its powerful tail and then drags it to water where it quickly drowns. Another way is to wait motionless for an animal to come to the water's edge and grabs it by its nose where it is held to drown.
In many places inhabited by crocodilians, the hot season brings drought that dries up their hunting grounds and takes away the means to regulate their body temperature. They allowed reptiles to dominate the terrestrial environment. Furthermore, many crocs protect themselves from this by digging burrows and entombing themselves in mud, waiting for months without access to food or water, until the rains arrive. To do this, they sink into a quiescent (寂静的) state called aestivation (休憩,夏眠).
Most of (At least nine species of) crocodilian are thought to aestivate during dry periods. Kennett and Christian's six-year study of Australian freshwater crocodiles - Crocodylus johnstoni (the King Crocodiles). The crocodiles spent almost four months a year underground without access to water. Doubly labeled water was used to measure field metabolic rates and water flux, and plasma (and cloacal fluid samples were taken at approximately monthly intervals during some years to monitorthe effects of aestivation with respect to the accumulation of nitrogenous wastes and electrolyte concentrations. Doubly found that the crocodiles' metabolic engines tick over, producing waste and using up water and fat reserves. Waste products are stored in the urine, which gets increasingly concentrated as the months pass. However, the concentration of waste products in the blood changes very little, allowing the crocodiles to function normally. Furthermore, though the animals lost water and body mass (just over one-tenth of their initial mass) while underground, the losses were proportional: on emergence, the aestivating crocodiles were not dehydrated and exhibited no other detrimental effects such as a decreased growth rate. Kennett and Christian believe this ability of individuals to sit out the bad times and endure long periods of enforced starvation must surely be key to the survival of the crocodilian line through time.
Reading passage 2 has seven paragraphs, A-G; Choose the correct heading for paragraphs A-G from the list below.
Write the correct number, i-xi, in boxes 14-20 on your answer sheet.
List of Headings
i The competitors with the dinosaur
ii A historical event for the Supreme survivors.
iii What makes the crocodile the fastest running animal on land
iv Regulated body temperature by the surrounding environment
v Underwater aid in body structure offered to a successful predator
vi The perfectly designed body for a great land roamer
vii Slow metabolisms which makes crocodile a unique reptile
viii The favorable features in the impact of a drought
ix Shifting Eating habits and food intake
x A project on a special mechanism
xi A unique findings has been achieved recently
14 Paragraph A
15 Paragraph B
16 Paragraph C
17 Paragraph D
18 Paragraph E
19 Paragraph F
20 Paragraph G
Complete the summary and write the correct answer (no more than two words or a number) in boxes 21-26 on your answer sheet.
In many places inhabited by crocodilians, most types of the crocodile has evolved a successful scheme to survive in the drought brought by a 21............. According to Kennett and Christian's six-year study of Australian freshwater crocodiles' aestivation, they found Aestivating crocodiles spent around 22............. a year without access to 23.............. The absolute size of body water pools declined proportionately with ......24...; thus there is no sign of 25............. and other health-damaging impact in the crocodiles even after an aestivation period. This super capacity helps crocodiles endure the tough drought without slowing their speed of 26............. significantly
14 ii 15 vi 16 v
17 iv 18 ix 19 viii
20 x 21 dry season/hot season/dry period
22 four months 23 water 24 body mass
25 dehydration 26 growth
The Exploration of Mars
In 1877, Giovanni Schiaparelli, an Italian astronomer, made drawings and maps of the Martian surface that suggested strange features. The images from telescopes at this time were not as sharp as today's. Schiaparelli said he could see a network of lines, or canali. In 1894, an American astronomer, Percival Lowell, made a series of observat