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An Australian research group may ease humanity’s collective conscience over a spate of prehistoric extinctions on the southern continent. The die-off, they say, was not the rapacious work of newly arrived humans, but was due rather to changing climate. Australia’s large prehistoric animals, called megafauna, were as bizarre as anything that lives there today. King of them all was the marsupial lion, a 130-kilogram meat-eater who lived alongside giant kangaroos, huge lizards called goannas, and Diprotodon, which resembled a three-tonne wombat. After the arrival of humans on the continent, at least 45,000 years ago, these weird and wonderful creatures began to die out. Experts blamed the colonizers, arguing that they launched a hunting ’ blitzkrieg’ that wiped out the megafauna (巨型动物) within a few generations. But the animals may have survived for a lot longer than people thought, argues Judith Field of the University of Sydney, who has analyzed fossil remains. Her excavations seem to show that man and beast lived side by side for as long as 15,000 years. She suspects that as Australia approached the most recent ice age, the growing cold and aridity turned much of the continent into a place where these large animals simply could not survive. Although man probably did hunt the large animals, the fact that they survived for so long argues against the blitzkrieg (闪电战) model, she adds. Field and her colleagues collected animal bones from a ten-metre-deep section of earth at Cuddle Springs, New South Wales. They focused on bones from four layers: two with evidence of human settlement, such as stone tools, and two deeper ones with no evidence of tools. They dated the bones by measuring the amounts of radioactive elements, such as uranium and thorium, that remained in the bones. They found that the various animal carcasses in each level would indeed have lived cheek by jowl with humans as recently as 30,000 years ago. The team report their research in Proceedings of the National Academy of Sciences. Proponents of the blitzkrieg model had previously argued that the dating of the Cuddle Springs material was not certain, but Field says their research clears up the matter. Well-preserved bones at other sites have been very hard to find, probably because they are too dry, whereas Cuddle Springs is the site of an old lake bed. A second group, reporting in the journal Memoirs of the Queensland Museum, has also unveiled evidence that climate change may have killed off many of Australia’s animals. By looking at smaller animal bones from the Darling Downs in Queensland, they show that their disappearance seems to have coincided with increasing dryness. But the matter is not settled yet, particularly as the timing of humans’ first foray into Australia has still not been agreed. Fossil evidence from Lake Mungo in New South Wales suggests that they may have arrived 60,000 years ago. And it is possible that they hastened the megafauna’s demise by burning habitats to make way for primitive agriculture. Field remains convinced, however, that it was climate that drove the animals to their death. "The arid zone grew to encompass 70% of the continent by 30,000 years ago," she says. "There would have been very few opportunities once it got dryer.\ Which of the following is INCORRECT according to the passage
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On the map there’s just one island, but when you get there you’ll find two distinct Sardinias. If you’re wondering which is the right destination for you, take the ice-cream test and try two gelati in Sardinia. On the wealthy Costa Smeralda I was served an ice-cream with enormous speed and efficiency by a Tom Cruise look-alike—all teeth, tan and ambition. But on Sardinia’s quieter western coast—the Riviera de Corallo—it was served, quite slowly and with elegance, by a girl with the face of an angel. My vote goes—narrowly—to this less-visited shore. There I found a seat in Alghero’s Piazza Civica, where the late afternoon sun was warming the old stones and the fishing boats were back at anchor just through the archway of the Porta al Mare. I reflected, as I ate my ice-cream and watched the locals make their evening passeggiata through the ancient square and the Door to the Sea, that the world is not such a bad place after all. By contrast, at a little cafe near the marina at Porto Cervo on the Costa Smeralda, watching beautiful young things leaping on and off their yachts, I reflected mainly that most people seemed to have a lot more money than I. It’s all very idyllic, the sea is always blue and the weather from May to October is invariably perfect. But is this plutocrats’ playground Sardinia No—not if you mean the rugged Sardinia with its roots in prehistory and its future in a possible split with mother Italy. To see the real Sardinia you could take the overnight ferry from Livorno on the Italian mainland to Olbia just below the Costa Smeralda. Perhaps hire a little Fiat—although Ferraris are available—and take the road that skirts the millionaire belt, heading north and then west. Head inland now, towards Sassari and Alghero. The hills crowd the shoreline, the villages are few and the roads are empty. Dotted around the fields, sticking up through olive groves like huge rock cones, are the remains of forts built by the mysterious Nuragic people, who came here long before the Romans and Phoenicians. A little way down the coast along a precipitous new highway is the ancient town of Bosa, where lace making and timber working keep many of the locals occupied. There is, of course, a great deal more to Sardinia than the Costa Smeralda and the Riviera del Corallo—there’s a whole islandful of things to see and do. South-central is where the main chain of mountains runs; snow-capped for four months of the year and a popular climbing and walking venue in gentler seasons. The coastline is longer than mainland Italy’s entire western side, with resorts dotted around natural harbours and scenic inlets. You could take in most of them in a two-day tour by car. But nothing compares with the Costa Smeralda or the Riviera del Corallo. It just depends on how you like your gelati. On the western coast of Sardinia he was served a gelati by ______.
A new generation of mind-enhancing drugs that act as "cosmetics" for the brain could become as common as a cup of coffee, according to an official investigation by leading scientists. Powerful stimulants that improve memory, intellectual agility or other aspects of mental performance will almost certainly be developed over the next 20 years. They will have few side-effects, little or no addictive properties and could be used for non-medical purposes such as boosting exam performance, making better business decisions or even eliminating bad memories, the scientists said. The first of these " cognition enhancers" is already being developed from research into existing drugs designed to treat medical problems. "In a world that is increasingly non-stop and competitive, the individual’s use of such substances may move from the fringe to the norm, with cognition enhancers used as coffee is today," says the Foresight report of the government’s Office of Science and Technology. "Cognition enhancers are likely to be developed to treat people who need to improve attention, memory or wakefulness and to help people to forget, sleep more efficiently and be less impulsive," the report says. Drugs that help people to forget disturbing experiences raise the prospect of a future portrayed in films such as Total Recall or Eternal Sunshine of the Spotless Mind, where characters are able to forget painful relationships, the scientists said. But the possibility raises disturbing practical, ethical and social issues. "It is possible that such an advance could usher in a new era of drug use without addiction," says the report. Professor Trevor Robbins of Cambridge University, one of the lead authors of the Foresight report, said yesterday that two drugs available on prescription were known to have mind-enhancing properties when taken by healthy people. Ritalin, which is given to children with attention-deficit disorder, is being used by a small number of students in an attempt to improve exam results and by businessmen to boost boardroom performance. Modafinil, a drug designed to treat narcolepsy, is also used to improve the concentration of healthy people so they can make more accurate decisions, Professor Robbins said. "What tends to happen is that the drug makes you less impulsive, it makes you more reflective about the problem so you take a bit longer, but you get it right," Professor Robbins said. Research into the chemistry of the brain has already identified about 60 natural compounds that affect the mind. Further work is almost certain to produce new drugs that could enhance mental performance, the Foresight report says. "If we ever find ourselves in a society that embraced cognition enhancers, ’mental cosmetics’ could become accepted and create new expectations about the performance and behaviour of individuals and groups," the report says. Cognitive enhancers could also be developed to help people come off addictive drugs or overcome post-traumatic stress disorder. All of the following are non-medical purposes of the new generation of mind-enhancing drugs EXCEPT ______.
A new generation of mind-enhancing drugs that act as "cosmetics" for the brain could become as common as a cup of coffee, according to an official investigation by leading scientists. Powerful stimulants that improve memory, intellectual agility or other aspects of mental performance will almost certainly be developed over the next 20 years. They will have few side-effects, little or no addictive properties and could be used for non-medical purposes such as boosting exam performance, making better business decisions or even eliminating bad memories, the scientists said. The first of these " cognition enhancers" is already being developed from research into existing drugs designed to treat medical problems. "In a world that is increasingly non-stop and competitive, the individual’s use of such substances may move from the fringe to the norm, with cognition enhancers used as coffee is today," says the Foresight report of the government’s Office of Science and Technology. "Cognition enhancers are likely to be developed to treat people who need to improve attention, memory or wakefulness and to help people to forget, sleep more efficiently and be less impulsive," the report says. Drugs that help people to forget disturbing experiences raise the prospect of a future portrayed in films such as Total Recall or Eternal Sunshine of the Spotless Mind, where characters are able to forget painful relationships, the scientists said. But the possibility raises disturbing practical, ethical and social issues. "It is possible that such an advance could usher in a new era of drug use without addiction," says the report. Professor Trevor Robbins of Cambridge University, one of the lead authors of the Foresight report, said yesterday that two drugs available on prescription were known to have mind-enhancing properties when taken by healthy people. Ritalin, which is given to children with attention-deficit disorder, is being used by a small number of students in an attempt to improve exam results and by businessmen to boost boardroom performance. Modafinil, a drug designed to treat narcolepsy, is also used to improve the concentration of healthy people so they can make more accurate decisions, Professor Robbins said. "What tends to happen is that the drug makes you less impulsive, it makes you more reflective about the problem so you take a bit longer, but you get it right," Professor Robbins said. Research into the chemistry of the brain has already identified about 60 natural compounds that affect the mind. Further work is almost certain to produce new drugs that could enhance mental performance, the Foresight report says. "If we ever find ourselves in a society that embraced cognition enhancers, ’mental cosmetics’ could become accepted and create new expectations about the performance and behaviour of individuals and groups," the report says. Cognitive enhancers could also be developed to help people come off addictive drugs or overcome post-traumatic stress disorder. Which of the following is NOT among the advances of the new drugs
A new generation of mind-enhancing drugs that act as "cosmetics" for the brain could become as common as a cup of coffee, according to an official investigation by leading scientists. Powerful stimulants that improve memory, intellectual agility or other aspects of mental performance will almost certainly be developed over the next 20 years. They will have few side-effects, little or no addictive properties and could be used for non-medical purposes such as boosting exam performance, making better business decisions or even eliminating bad memories, the scientists said. The first of these " cognition enhancers" is already being developed from research into existing drugs designed to treat medical problems. "In a world that is increasingly non-stop and competitive, the individual’s use of such substances may move from the fringe to the norm, with cognition enhancers used as coffee is today," says the Foresight report of the government’s Office of Science and Technology. "Cognition enhancers are likely to be developed to treat people who need to improve attention, memory or wakefulness and to help people to forget, sleep more efficiently and be less impulsive," the report says. Drugs that help people to forget disturbing experiences raise the prospect of a future portrayed in films such as Total Recall or Eternal Sunshine of the Spotless Mind, where characters are able to forget painful relationships, the scientists said. But the possibility raises disturbing practical, ethical and social issues. "It is possible that such an advance could usher in a new era of drug use without addiction," says the report. Professor Trevor Robbins of Cambridge University, one of the lead authors of the Foresight report, said yesterday that two drugs available on prescription were known to have mind-enhancing properties when taken by healthy people. Ritalin, which is given to children with attention-deficit disorder, is being used by a small number of students in an attempt to improve exam results and by businessmen to boost boardroom performance. Modafinil, a drug designed to treat narcolepsy, is also used to improve the concentration of healthy people so they can make more accurate decisions, Professor Robbins said. "What tends to happen is that the drug makes you less impulsive, it makes you more reflective about the problem so you take a bit longer, but you get it right," Professor Robbins said. Research into the chemistry of the brain has already identified about 60 natural compounds that affect the mind. Further work is almost certain to produce new drugs that could enhance mental performance, the Foresight report says. "If we ever find ourselves in a society that embraced cognition enhancers, ’mental cosmetics’ could become accepted and create new expectations about the performance and behaviour of individuals and groups," the report says. Cognitive enhancers could also be developed to help people come off addictive drugs or overcome post-traumatic stress disorder. Which of the following is INCORRECT according to the passage
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