题目内容
It is hard to box against a southpaw, as Apollo Creed found out when he fought Rocky Balboa in the first of an interminable series of movies. While "Rocky" is fiction, the strategic advantage of being left-handed in a fight is very real, simply because most right-handed people have little experience of fighting left-handers, but not vice versa. And the same competitive advantage is enjoyed by left-handers in other sports, such as tennis and cricket.The orthodox view of human handedness is that it is connected to the bilateral specialization of the brain that has concentrated language-processing functions on the left side of that organ. Because, long ago in the evolutionary past, an ancestor of humans ( and all other vertebrate animals ) underwent a contortion that twisted its head around 180~ relative to its body, the left side of the brain controls the right side of the body, and vice versa. In humans, the left brain (and thus the right body) is usually dominant. And on average, lefthanders are smaller and lighter than right-handers. That should put them at an evolutionary disadvantage. Sporting advantage notwithstanding, therefore, the existence of left-handedness poses a problem for biologists. But Charlotte Faurie and Michel Raymond, of the University of Montpellier Ⅱ , in France, think they know the answer. As they report in the Proceedings of the Royal Society, there is a clue in the advantage seen in boxing.As any schoolboy could tell you, winning fights enhances your status. If, in prehistory, this translated into increased reproductive success, it might have been enough to maintain a certain proportion of left-handers in the population, by balancing the costs of being left-handed with the advantages gained in fighting. If that is true, then there will be a higher proportion of left-handers in societies with higher levels of violence, since the advantages of being left-handed will be enhanced in such societies. Dr Faurie and Dr Raymond set out to test this hypothesis.Fighting in modem societies often involves the use of technology, notably firearms, that is unlikely to give any advantage to left-handers. So Dr Faurie and Dr Raymond decided to confine their investigation to the proportion of left-handers and the level of violence ( by number of homicides) in traditional societies.By trawling the literature, checking with police departments, and even going out into the field and asking people, the two researchers found that the proportion of left-handers in a traditional society is, indeed, correlated with its homicide rate. One of the highest proportions of left-handers, for example, was found among the Yanomamo of South America. Raiding and warfare are central to Yanomamo culture. The murder rate is 4 per 1 000 inhabitants per year (compared with, for example, 0.068 in New York). And, according to Dr Faurie and Dr Raymond, 22.6% of Yanomamo are left-handed. In contrast, Dioula-speaking people of Burkina Faso in West Africa are virtual pacifists. There are only 0. 013 murders per 1 000 inhabitants among them and only 3.4% of the population is left-handed.While there is no suggestion that left-handed people are more violent than the right-handed, it looks as though they are more successfully violent. Perhaps that helps to explain the double meaning of the word "sinister". The researchers choose to carry out their study in traditional societies because（）
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The world seems increasingly divided into those who favor genetically modified (GM) foods and those who fear them. Advocates assert that growing genetically altered crops can be kinder to the environment and that eating foods from those plants is perfectly safe. And, they say, genetic engineering—which can induce plants to grow in poor soils or to produce more nutritious foods—will soon become an essential tool for helping to feed the world’s burgeoning population. Skeptics contend that GM crops could pose unique risks to the environment and to health—risks too troubling to accept placidly. Taking that view, many European countries are restricting the planting and importation of GM agricultural products. Much of the debate hinges on perceptions of safety. But what exactly does recent scientific research say about the hazards Advocates of GM, or transgenic, crops say the plants will benefit the environment by requiring fewer toxic pesticides than conventional crops. But critics fear the potential risks and wonder how big the benefits really are. "We have so many questions about these plants," remarks Guenther Stotzky, a soil microbiologist at New York University. "There’s a lot we don’t know and need to find out. " As GM crops multiply in the landscape, unprecedented numbers of researchers have started fanning into the fields to get the missing information. Some of their recent findings are reassuring; others suggest a need for vigilance. Every year U.S. growers shower crops with an estimated 971 million pounds of pesticides, mostly to kill insects, weeds and fungi. But pesticide residues linger on crops and the surrounding soil, leaching into groundwater, running into streams and getting gobbled up by wildlife. The constant chemical trickle is an old worry for environmentalists. In the mid-1990s agribusinesses began advertising GM seeds that promised to reduce a farmer’s use of toxic pesticides. Today most GM crops—mainly soybean, corn, cotton and canola—contain genes enabling them to either resist insect pests or tolerate weed-killing herbicides. The insect-resistant varieties make their own insecticide, a property meant to reduce the need for chemical sprays. The herbicidetolerant types survive when exposed to broad-spectrum weed killers, potentially allowing farmers to forgo more poisonous chemicals that target specific weed species. Farmers like to limit the use of more hazardous pesticides when they can, but GM crops also hold appeal because they simplify operations (reducing the frequency and complexity of pesticide applications) and, in some cases, increase yields. But confirming environmental benefit is tricky. Virtually no peer-reviewed papers have addressed such advantages, which would be expected to vary from plant to plant and place to place. Some information is available, however. According to the U.S. Department of Agriculture, farmers who plant herbicidetolerant crops do not necessarily use fewer sprays, but they do apply a more benign mix of chemicals. For instance, those who grow herbicide-tolerant soybeans typically avoid the most noxious weed killer, turning instead to glyphosate herbicides, which are less toxic and degrade more quickly. Insect-resistant crops also bring mixed benefits. To date, insect resistance has been provided by a gene from the soil bacterium Bacillus thuringiensis (Bt). This gene directs cells to manufacture a crystalline protein that is toxic to certain insects—especially caterpillars and beetles that gnaw on crops—but does not harm other organisms. The toxin gene in different strains of Bacillus. thuringiensis can affect different mixes of insects, so seed makers can select the version that seems best suited to a particular crop. Defining the environmental risks of GM crops seems even harder than calculating their benefits. At the moment, public attention is most trained on Bt crops, thanks to several negative studies. Regulators, too, are surveying the risks intensely. This spring or summer the EPA is expected to issue major new guidelines for Bt crops, ordering seed producers to show more thoroughly that the crops can be planted safely and monitored in farm fields. In the face of mounting consumer concern, scientists are stepping up research into the consequences of Bt and other GM crops. Among their questions: How do Bt crops affect "nontarget" organisms—the innocent bugs, birds, worms and other creatures that happen to pass by the modified plants Will GM crops pollinate nearby plants, casting their genes into the wild to create superweeds that grow unchecked What are the odds that the genetically engineered traits will lose their ability to protect against insects and invasive weeds, leaving GM plants suddenly vulnerable People’s worries about GM plants include the following problems EXCEPT______.
People do not have secret trolleys at the supermarket, so how can it be a violation of their privacy if a grocer sells their purchasing habits to a marketing firm If they walk around in public view, what harm can cameras recording their movements cause A company is paying them to do a job, so why should it not read their e-mails when they are at work How, what and why, indeed. Yet, in all these situations, most people feel a sense of unease. The technology for gathering, storing, manipulating and sharing information has become part of the scenery, but there is little guidance on how to resolve the conflicts created by all the personal data now washing around. The author in the end of the passage ______ the idea of applying contextual integrity to issues concerning privacy. [A] approves of [B] disagrees with [C] is critical of [D] is indifferent to
In sixteenth-century Italy and eighteenth-century France, waning prosperity and increasing social unrest led the ruling families to try to preserve their superiority by withdrawing from the lower and middle classes behind barriers of etiquette. In a prosperous community, on the other hand, polite society soon adsorbs the newly rich, and in England there has never been any shortage of books on etiquette for teaching them the manners appropriate to their new way of life. Every code of etiquette has contained three elements: basic moral duties; practical rules which promote efficiency; and artificial, optional graces such as formal compliments to, say, women on their beauty or superiors on their generosity and importance. In the first category are considerations for the weak and respect for age. Among the ancient Egyptians the young always stood in the presence of older people. Among the Mponguwe of Tanzaia, the young men bow as they pass the huts of the elders. In England, until about a century ago, young children did not sit in their parents’ presence without asking permission. Practical rules are helpful in such ordinary occurrences of social life as making proper introductions at parties or other functions so that people can be brought to know each other. Before the invention of the fork, etiquette directed that the fingers should be kept as clean as possible; before the handkerchief came into common use, etiquette suggested that after spitting, a person should rub the spit inconspicuously underfoot. Extremely refined behavior, however, cultivated as an art of gracious living, has been characteristic only of societies with wealth and leisure, which admitted women as the social equals of men. After the fall of Rome, the first European society to regulate behavior in private life in accordance with a complicated code of etiquette was twelfth-century Province, in France. Provinces had become wealthy. The lords had returned to their castle from the crusades, and there the ideals of chivalry grew up, which emphasized the virtue and gentleness of women and demanded that a knight should profess a pure and dedicated love to a lady who would be his inspiration, and to whom he would dedicate his valiant deeds, though he would never come physically close to her. This was the introduction of the concept of romantic love, which was to influence literature for many hundreds of years and which still lives on in a debased form in simple popular songs and cheap novels today. In Renaissance Italy too, in the fourteenth and fifteenth centuries, a wealthy and leisured society developed an extremely complex code of manners, but the rules of behavior of fashionable society had little influence on the daily life of the lower classes. Indeed many of the rules, such as how to enter a banquet room, or how to use a sword or handkerchief for ceremonial purposes, were irrelevant to the way of life of the average working man, who spent most of his life outdoors or in his own poor hut and most probably did not have a handkerchief, certainly not a sword, to his name. Yet the essential basis of all good manners does not vary. Consideration for the old and weak and the avoidance of banning or giving unnecessary offence to others is a feature of all societies everywhere and at all levels from the highest to the lowest. Etiquette as an art of gracious living is quoted as a feature of which country
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