单选题{{B}}Passage 4{{/B}} The evolution of sex ratios has produced, in most plants and animals with separate sexes, approximately equal numbers of males and females. Why should this be so? Two main kinds of answers have been offered. One is couched in terms of advantage to population. It is argued that the sex ratio will evolve so as to maximize the number of meetings between individuals of the opposite sex. This is essentially a "group selection" argument. The other, and in my view correct, type of answer was first put forward by Fisher in 1930. This "genetic" argument starts from the assumption that genes can influence the relative numbers of male and female offspring produced by an individual carrying the genes. That sex ratio will be favored which maximizes the number of descendants an individual will have and hence the number of gene copies transmitted. Suppose that the population consisted mostly of females, then an individual who produced sons only would have more grandchildren. In contrast, if the population consisted mostly of males, it would pay to have daughters. If, however, the population consisted of equal numbers of males and females, sons and daughters would be equally valuable. Thus a one-to-one sex ratio is the only stable ratio; it is an "evolutionarily stable strategy." Although Fisher wrote before the mathematical theory of games had been developed, his theory incorporates the essential feature of a game that the best strategy to adopt depends on what others are doing. Since Fisher's time, it has been realized that genes can sometimes influence the chromosome or gamete in which they find themselves so that the gamete will be more likely to participate in fertilization. If such a gene occurs on a sex-determining (X or Y) chromosome, then highly aberrant sex ratios can occur. But more immediately relevant to game theory are the sex ratios in certain parasitic wasp species that have a large excess of females. In these species, fertilized eggs develop into females and unfertilized eggs into males. A female stores sperm and can determine the sex of each egg she lays by fertilizing it or leaving it unfertilized. By Fisher's argument, it should still pay a female to produce equal numbers of sons and daughters. Hamilton, noting that the eggs develop within their host—the larva of another insect—and that the newly emerged adult wasps mate immediately and disperse, offered a remarkably cogent analysis. Since only one female usually eggs in a given larva, it would pay her to produce one male only, because this one could fertilize all his sisters on emergence. Like Fisher, Hamilton looked for an evolutionarily stable strategy, but he went a step further in recognizing that he was looking for a strategy.

单选题Questions 16 to 20 are based on the following passage. Religion consists of conscious ideas, hopes, enthusiasms, and objects of worship; it operates by grace and flourishes by prayer. Reason, on the other hand, is a mere principle or potential order, on which indeed we may come to reflect but which exists in us ideally only, without variation or stress of any kind. We conform or do not conform to it; it does not urge or chide us, not call for any emotions on our part other than those naturally aroused by the various objects which it unfolds in their true nature and proportion. Rationality is nothing but a form, an ideal constitution which experience may more or less embody. Religion is a part of experience itself, a mass of sentiments and ideas. The one is an inviolate principle, the other a changing and struggling force. And yet this struggling and changing force of religion seems to direct man toward something eternal. It seems to make for an ultimate harmony within the soul and for an ultimate harmony between the soul and all that the soul depends upon. Religion, in its intent, is a more conscious and direct pursuit of the Life of Reason than is society, science, or art, for these approach and fill out the ideal life tentatively and piecemeal, hardly regarding the foal or caring for the ultimate justification of the instinctive aims. Nevertheless, we must confess that this religious pursuit of the Life of Reason has been singularly abortive. Those within the pale of each religion may prevail upon themselves, to express satisfaction with its results, thanks to a fond partiality in reading the past and generous draughts of hope for the future ; but any one regarding the various religions at once and comparing their achievements with what reason requires, must feel how terrible is the disappointment which they have one and all prepared for mankind. To confuse intelligence and dislocate sentiment by gratuitous fictions is a short-sighted way of pursuing happiness. Thus religion too often debauches the morality it comes to sanction and impedes the science it ought to fulfill. Religion pursues rationality through the imagination. When it explains events or assigns causes, it is an imaginative substitute for science. When it gives precepts, insinuates ideals, or remoulds aspiration, it is an imaginative substitute for wisdom-I mean for the deliberate and impartial pursuit of all food. The condition and the aims of life are both represented in religion poetically, but this poetry tends to arrogate to itself literal truth and moral authority, neither of which it possesses. Hence the depth and importance of religion becomes intelligible no less than its contradictions and practical disasters. Its object is the same as that of reason, but its method is to proceed by intuition and by unchecked poetical conceits.

单选题In this part you are going to read six passages. Each of the passages is followed by some questions or unfinished statements. For each question there are four choices marked A, B, C and D. Decide on the best choice according to the passage you read and write your choice. The relationship between formal education and economic growth in poor countries is widely misunderstood by economists and politicians alike progress in both area is undoubtedly necessary for the social, political and intellectual development of these and all other societies, however, the conventional view that education should be one of the very highest priorities for promoting rapid economic development in poor countries is wrong. We are fortunate that is it, because new educational systems there and putting enough people through them to improve economic performance would require two or three generations. The findings of a research institution have consistently shown that workers in all countries can be trained on the job to achieve radical higher productivity and, as a result, radically higher standards of living. Ironically, the first evidence for this idea appeared in the United States. Not long ago, with the country entering a recessing and Japan at its pre-bubble peak. The U. S. workforce was derided as poorly educated and one of primary cause of the poor U. S. economic performance. Japan was, and remains, the global leader in automotive-assembly productivity. Yet the research revealed that the U. S. factories of Honda Nissan, and Toyota achieved about 95 percent of the productivity of their Japanese counterparts a result of the training that U. S. workers received on the job. More recently, while examing housing construction, the researchers discovered that illiterate, non-English-speaking Mexican workers in Houston, Texas, consistently met best-practice labor productivity standards despite the complexity of the building industry's work. What is the real relationship between education and economic development? We have to suspect that continuing economic growth promotes the development of education even when governments don't force it. After ail, that's how education got started. When our ancestors were hunters and gatherers 10, 000 years ago, they didn't have time to wonder much about anything besides finding food. only when humanity began to get its food in a more productive way was there time for other things. As education improved, humanity's productivity potential, they could in turn afford more education. This increasingly high level of education is probably a necessary, but not a sufficient, condition for the complex political systems required by advanced economic performance. Thus poor countries might not be able to escape their poverty traps without political changes that may be possible only with broader formal education. A lack of formal education, however, doesn't constrain the ability of the developing world's workforce to substantially improve productivity to the forested future. on the contrary, constraints on improving productivity explain why education isn't developing more quickly there than it is.

单选题 What are the chances that we will encounter some alien form of life, as we explore the galaxy.If the argument about the time scale for the appearance of life on Earth is correct, there ought to be many other stars, whose planets have life on them. Some of these stellar systems could have formed 5 billion years before the Earth. So why is the galaxy not crawling with self designing mechanical or biological life forms? Why hasn't the Earth been visied, and even colonized. I discount suggestions that UFOs contain beings from outer space. I think any visits by aliens would be much more obvious, and probably also, much more unpleasant. What is the explanation of why we have not been visited? One possibility is that the argument about the appearance of life on Earth is wrong. Maybe the probability of life spontaneously appearing is so low that Earth is the only planet in the galaxy, or in the observable universe, in which it happened. Another possibility is that there was a reasonable probability of forming self-reproducing system, like cells, but most of these forms of life did not evolve intelligence. A third possibility is that there is a reasonable probability for life to form, and to evolve to intelligent beings, in the external transmission phase. But at that point, the system becomes unstable, and the intelligent life destroys itself. This would be a very pessimistic conclusion. I very much hope it isn't true. I prefer a fourth possibility: there are other forms of intelligent life out there, but we have been overlooked. There used to be a project called SETI, the search for extraterrestrial intelligence. It involved scanning the radio frequencies, to see if we could pick up signals from alien civilizations. I thought this project was worth supporting, though it was cancelled due to a lack of funds. But we should have been wary of answering back, until we have developed a bit further. Meeting a more advanced civilization, at our present stage, might be a bit like the original inhabitants of America meeting Columbus. I don't think they were better off for it.

单选题There I came into______ with some of the finest craftsmen I have ever met.

单选题For scientists who study human evolution, fossil remains provide the only direct evidence of our ancient ancestors. Access to these paleoanthropological Rosetta stones, how- ever, is limited by protective curators who are often reluctant to lend the fragile fossils. And in the case of fossil skulls, nature preserves critical information in the largely in- accessible interior. But help is on the way. At the annual meeting of the American Association of Physical Anthropologists in Salt Lake City this past April, researchers discussed how medical imaging, virtual reality and computer-controlled modelling technologies get around these obstacles noninvasively. Three-dimensional medical imaging based on computed tomography (CT) scans was developed in the early 1980s. On a computer, surgeons could electronically remove the patient's soft tissue and then explore the virtual skull inside and out before operating. It wasn't long before Glenn Conroy of Washington University and his colleagues demonstrated that these same techniques could also be applied to fossils, in which sediments take the place of soft tissue. With advances in computer graphics and computational power, paleoanthropologists can now perform on their computers a wide range of investigations that are impossible to attempt on the original fossil. Missing features on one Side of the skull can be re-created by mirroring the preserved features (postmortem deformations can be similarly rectified) and tiny, hidden structures such as the inner ear can be magnified for closer examination. Moreover, as Christoph P. E. Zollikofer and Marcias Ponce de Leon of the University of Zurich and others have shown, anthropologists can reconstruct fragmented fossils on-screen. The standard repertoire of measurements can also be made virtually, in most cases with the same degree of accuracy afforded by handheld calipers. And with the creation of a virtual "endocast", brain volume can be determined reliably. In fact, Conroy's recent re- Search has revealed a major discrepancy between the estimated and actual brain volume of an early hominid called Stw 505 (or Mr. Pies). Conroy suspects that the estimated cranial capacity of some other fossils might also be incorrect--a hunch that, if substantiated, could have important implications for our understanding of brain evolution.

单选题The walkers in front crossed the ledge easily, seemingly ______ of the fact that there was a 3000-foot drop on either side. A. attentive B. remindful C. oblivious D. pretentious

单选题Cigarette smoking is a great health ______and may lead to fatal diseases.(2004年武汉大学考博试题)

单选题New research from Australia supports the belief that many pet owners have—it shows that pets are good for your health. The 1 of this new study suggest that people who have pets are 2 less risk from heart disease than 3 who do not. Ironically this 4 study on pets was intended to 5 the myth that pets are good for your health. Earlier research 6 the benefits of owning pets received a lot of 7 , but the results were not good enough to 8 the more skeptical doctors. The new research was carried 9 over three years and examined 6000 people, the largest group yet involved in 10 a study. They took tests that measured a 11 of different factors known to be 12 in heart disease— 13 and blood levels of cholesterol (胆固醇) and triglyceride (甘油三酸酯). 14 , people were asked about their lifestyles. The 800 people who owned pets had 15 levels on each of the factors 16 than those who did not own pets. The differences were even greater than those found in similar studies on people who 17 to vegetarian diets or took 18 exercise. The study also showed that it did not matter 19 kind of pet was owned—a cat was as good as a dog—so the benefits could not be attributed 20 the exercise involved in walking a dog.

单选题Sea rise as a consequence of global warming would immediately threaten that large fraction of the globe living at sea level. Nearly one-third of all human beings live within 36 miles of a coastline. Most of the world's great seaport cities would be 56 : New Orleans, Amsterdam, Shanghai, and Cairo. Some countries- Maldives Islands in the Indian Ocean, islands in the Pacific- would be inundated. Heavily populated coastal areas such as in Bangladesh and Egypt, 57 large populations occupy low-lying areas, would suffer extreme 58 . Warmer oceans would spawn stronger hurricanes and typhoons, 59 in coastal flooding, possibly swamping valuable agricultural lands around the world. 60 water quality may result as 61 flooding which forces salt water into coastal irrigation and drinking water supplies, and irreplaceable, natural 62 could be flooded with ocean water, destroying forever many of the 63 plant and animal species living there. Food supplies and forests would be 64 affected. Changes in rainfall patterns would disrupt agriculture. Warmer temperatures would 65 grain-growing regions pole-wards. The warming would also increase and change the pest plants, such as weeds and the insects 66 the crops. Human health would also be affected. Warming could 67 tropical climate bringing with it yellow fever, malaria, and other diseases. Heat stress and heat mortality could rise. The harmful 68 of localized urban air pollution would very likely be more serious in warmer 69 . There will be some 70 from warming. New sea-lanes will open in the Arctic, longer growing seasons further north will 71 new agricultural lands, and warmer temperature will make some of today's colder regions more 72 . But these benefits will be in individual areas. The natural systems--both plant and animal- will be less able than man to cope and 73 . Any change of temperature, rainfall, and sea level of the magnitude now 74 will be destructive to natural systems and living things and hence to man as well. The list of possible consequences of global warming suggests very clearly that we must do everything we can now to understand its causes and effects and to take all measures possible to prevent and adapt to potential and inevitable disruptions 75 by global warming.

单选题 Abortion. The word alone causes civil conversation to flee the room. This is largely because the pro-choice and pro-life positions are being defined by their extremes, by those who scream accusations instead of arguments. More reasonable voices and concerns, on both sides of the fence, are given little attention. For example, pro-life extremists seem unwilling to draw distinctions between some abortions and others, such as those resulting from rape with an underage child. They would make no exception in the recent real-life case of a woman who discovered in her fifth month that her baby would be born dead due to severe disabilities. On the other hand, pro-choice extremists within feminism insist on holding inconsistent positions. The pregnant woman has an unquestionable fight to abort, they claim. Yet if the biological father has no say whatsoever over the woman's choice, is it reasonable to impose legal obligations upon him for child support? Can absolute legal obligation adhere without some sort of corresponding legal rights? The only hope for progress in the abortion dialogue lies in the great excluded middle,in the voices of average people who see something wrong with a young girl forced to bear the baby of a rapist. Any commentary on abortion should include a statement of the writer's position. I represent what seems to be a growing "middle ground" in pro-choice opinion. Legally, I believe in the right of every human being to medically control everything under his or her own skin. Many things people have a legal right to do, however, seem clearly wrong tome. adultery, lying to friends, walking past someone who is bleeding on the street. Some forms of abortion fall into that category. Morally speaking, my doubts have become so extreme that I could not undergo the procedure past the first three months and I would attempt to dissuade friends from doing so. Fanatics on both sides are using reprehensible and deceitful tactics. An honest dialogue on abortion must start by re-setting the stage, by denouncing the approaches that block communication.

单选题The discovery of the Antarctic not only proved one of the most interesting of all geographical adventures, but created what might be called "the heroic age of Antarctic exploration". By their tremendous heroism, men such as Shackleton, Scott, and Amundsen caused a new continent to emerge from the shadows, and yet that heroic age, little more than a century old, is already passing. Modern science and inventions are revolutionizing the techniques of former explorers, and, although still calling for courage and feats of endurance, future journeys into these icy wastes will probably depend on motor vehicles equipped with caterpillar traction rather than on the dogs that earlier discoverers found so invaluable. Few realize that this Antarctic continent is almost equal in size to South America, and enormous field of work awaits geographers and prospectors. The coasts of this continent remain to be accurately charted, and the mapping of the whole of interior presents formidable task to the cartographers who undertake the work. Once their labors are completed, it will be possible to prospect the vast natural resources which scientists believe will furnish one of the largest treasure hoards of metals and minerals the world has yet known, an almost inexhaustible sources of copper, coal, uranium, and many other ores will become available to man. Such discoveries will usher in an era of practical exploitation of the Antarctic wastes. The polar darkness which hides this continent for the six winter months will be defeated by huge batteries of light, and make possible the establishing of air fields for the future intercontinental air service by making these areas as light as day. Present flying routes will completely change, for the Antarctic refueling bases will make flight from Australia to South America comparatively easy over the 5,000 miles journey. The climate is not likely to offer an insuperable problem, for the explorer Admiral Byrd has shown that the climate is possible even for men completely untrained for expeditions into those frozen wastes. Some of his parties were men who had never seen snow before, and yet he records that they survived the rigors of the Antarctic climate comfortably, so that, provided that the appropriate installations are made, we may assume that human beings from all countries could live there safely. Byrd even affirms that it is probably the most health climate in the world, for the intense cold of thousands of years has sterilized this continent, and rendered it absolutely germfree, with the consequences that ordinary and extraordinary sicknesses and disease from which man suffers in other zones with different climates are here utterly unknown. There exist no problems of conservation and preservation of food supplies, for the latter keep indefinitely without any signs of deterioration; it may even be that later generations will come to regard the Antarctic as the natural storehouse for the whole world. Plans are already on foot to set up permanent bases on the shores of this continent, and what so few years ago was regarded as a "dead continent" now promises to be a most active centre of human life and endeavor.

单选题The appeal for funds did not ______ much of respond A. drag B. elicit C. tempt D. attract

单选题It comes as no surprise that societies have codes of behavior. The character of the codes, on the other hand ,can often be ______. A. predictable B. unexpected C. explicit D. confusing

单选题Howard Johnson ______ a better brand of ice cream and a new way to sell it. A. came up with B. came to C. came across D. came off

单选题Some studies confirmed that this kind of eye disease was ______ in tropic countries.(2005年电子科技大学考博试题)

单选题No other newspaper columnist has managed as yet to rival Ann Landers' popularity in terms of readership.