托福TPO阅读49原文+题目+答案

托福TPO阅读49原文（篇）-Mating Songs of Frogs
The calling or singing of frogs plays an important role in their reproduction—specifically, in helping individuals find and select mates. Sound has many advantages as a communication signal.When sounds are broadcast, the auditory receptors do not need to be in a particular orientation relative to the sound source in order to receive stimulation. Loud songs, particularly those made by choruses of frogs calling together, can travel long distances and thus attract distant frogs.Sounds travel around large obstacles. These advantages are not found in the visual modality,where the receiver must be attentive and have its visual receptor orientated in the correct direction.Further, most frogs and toads breed at night, when light levels are low but sounds can be easily localized. We can conclude that auditory signals are used by frogs and toads because they can be effective over long distances at night.
Male frogs do most of the courtship calling. Other male frogs can respond by adding their voices to form a calling chorus. Male frogs can also vocalize to each other as part of aggressive displays.Aggressive calls can be distinct from the advertisement calls used to attract females. Females can respond to male songs by moving toward the sound source or by selecting certain males as reproductive partners. In some species females also respond to males by calling: receptive pairs can even perform duets. Predators may also cue in on calling frogs as potential prey.Frog songs contain several potentially important pieces of information about the calling male.First, sound amplitude can indicate the size of the individual that is Galling. Since many frogs exhibit indeterminate growth (i.e., they keep getting bigger as they get older), size is a good predictor of relative age. In many species, call amplitude is increased by specialized vocal sacs that can enlarge as the animal grows; thus, older frogs produce louder calls. The male’s age matters to the female because older frogs have successfully survived the environmental hazards that the offspring they sire will soon be facing. Amplitude can also convey information on how far away the calling frog is or, for choruses, how many frogs are calling together. An intensely vocalizing chorus may indicate a particularly favorable breeding site. Sound amplitude(subjectively: loudness) can be an ambiguous cue for a female, however. A very intense sound can indicate an old male at some distance or a younger male that is close. A close, small chorus could be confused with a louder chorus that is farther away.
Sound frequencies-or pitch-can also convey information about the calling male because the vocal apparatus grows larger as the frog grows older. In some frogs, the pitch of individual sounds varies with so that older and larger males give lower-pitched calls. Sound pitch is affected by temperature; small males can mimic the lower pitch of larger, older males by calling from colder locations. Finally, the length of time that an individual can afford to spend calling is a good indicator of his health. Many frogs invest considerable energy in calling, both because they do not feed and because it is a physically demanding behavior that relies on rapid muscular contractions of the vocalization apparatus. This effort can be debilitating in a male frog that is not in top physical condition. Calling in tree frogs is said to be the most energetically expensive behavior yet measured any vertebrate.
Sound frequencies and the overall temporal pattern (rhythm and rate) of the song can also reveal the species of the calling male. The frequencies sounds and their temporal patterns are speciesspecific.The species of a potential mate is extremely important to the female. Females that choose to mate with members of another species risk losing the energy invest in eggs because the hybrid offspring will not survive and reproduce.
Thu complexity of a frog song can also affect how attractive it is to a female. The songs of male tungara frogs, for example, can consist simply of short high-frequency “whines” or by several lower-frequency "chucks." More females approach loudspeakers playing whines plus chucks than whines alone. The addition of chucks, however, also has the disadvantage of attracting bats that eat the frogs.
 
      托福TPO阅读49原文+题目：
1. According to paragraph 1, all of the following are mentioned as true of the mating calls of frogs
EXCEPT:
A. They can reach frogs in far-off locations.
B. They are not blocked by objects of substantial size.
C. They are often combined with non-auditory signals.
D. They err be received without the frog’s needing to orient itself toward the direction of the signal.
2. The author provides information about "the visual modality" in order to
A. emphasize that visual information plays a significant part in frog breeding
B. explain why some frogs breed at night, while others breed during the day
C. indicate the resourcefulness with which frogs overcome obstacles in sound travel during the breeding process
D. argue that auditory signals have advantages over visual signals for frog reproduction
3. The word "potential" in the passage is closest in meaning to
A. occasional
B. possible
C. easy
D. hidden
4.The word "favorable” in the passage is closest in meaning to
A. well populated
B. distant
C. extensive
D. advantageous
5.According to paragraph 3，female frogs who listen to frog songs are trying to determine whether a future mate
A. can protect future offspring from predators
B. has an important social position within the male chorus
C. has reached an age that indicates the ability to survive environmental challenges
D. is young enough to be able to produce many offspring
6. It can be inferred from paragraph 3 that female frogs are seeking mates who
A. can inhabit a variety of breeding sites
B. can occupy habitats at a distance from those of younger male frogs
C. have protected previous mates from environmental hazards
D. are likely to pass on traits that strengthen their offspring's chances of survival
7. The word "ambiguous" in the passage is closest in meaning to
A. unexpected
B. unclear
C. important
D. unhelpful
8.The word "convey" in the passage is closest in meaning to
A. transmit
B. add to
C. amplify
D. correct
9.Paragraph 4 implies that young frogs may call from cold areas for which of the following reasons?
A. To indicate superior strength over older males
B. To appear more attractive to females by sounding older than actually are
C. To be able to spend less energy in producing their call
D. To compete against fewer males for a female’s attention
10.In paragraph 4, why does the author mention that tree frog calling is said to be “the most energetically expensive behavior yet measured in any vertebrate"?
A. explain why it is important for tree frogs to be in top physical condition
B. To distinguish tree frogs from other species of frogs
C. To indicate that survival is more difficult for frogs than for other vertebrates
D. To emphasize how physical effort calling requires
11.It can be inferred paragraph 5 that having species specific songs benefits frogs in which of the following ways?
A. It enables frogs to better protect eggs from being damaged by members of other species.
B. It make it possible for frogs to judge their distance from potential mates.
C. It helps frogs to avoid having offspring that cannot survive and reproduce
D. It makes it possible for frogs to invest more of their energy into producing eggs.
12.According to paragraph 6, tungara frogs add a chuck sound to their call in order to
A. make themselves more attractive to females
B. keep predators at a safe distance
C. attract frogs of different species
D. increase the loudness of their calls
13. Look at the four squares ■ that indicate where the following sentence could be added to the passage.
But a frog’s age is not the only influence on the pitch of a frog’s call.
Where would the sentence best fit?
■ Sound frequencies-or pitch-can also convey information about the calling male because the vocal apparatus grows larger as the frog grows older. ■ In some frogs, the pitch of individual sounds varies with so that older and larger males give lower-pitched calls. ■ Sound pitch if affected by temperature; small males can mimic the lower pitch of larger, older males by calling from colder locations. ■Finally, the length of time that an individual can afford to spend calling is a good indicator of his health. Many frogs invest considerable energy in calling, both because they do not feed and because it is a physically demanding behavior that relies on rapid muscular contractions of the vocalization apparatus. This effort can be debilitating in a male frog that is not in top physical condition. Calling in tree frogs is said to be the most energetically expensive behavior yet measured any vertebrate.
14.Directions: An introductory sentence for a brief summary of the passage is provided below.Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.
The calling or singing of frogs is a form of communication.
1.For frogs and toads, sound has a number of advantages over visual signals as a medium of communication over long distances at night.
2.Calling is performed primarily by male frogs to attract mates for reproduction and to actively compete with other male frogs for females.
3.Depending on the species, female frogs can obtain information from a male’s song about age,health, and species of the caller.
4.In some species both males and females produce mating songs either as individual pairs or as choruses, though the choruses are likely to attract predators;
5.Frog calls are difficult to interpret because old frogs and young frogs in cool places produce the same song, and near frogs that are old and weak can sound like fit young frogs calling from a distance.
6.Because calling is such a tiring activity for frogs, it is used to communicate only about biologically necessary activities and often in groups that distribute the calling effort among many individuals.
 
托福TPO阅读49原文（第二篇）-Human Impacts on Biogeography
Biologists, who commonly study the distribution of plant and animal species in different environments—their biogeography—strive to develop interpretations or explanations of the patterns of species distribution, but these may be incorrect if the effects of human beings are not taken into consideration. In some cases, these effects may be accidental; for example, some species of rat were unintentionally transported aboard ships from Europe to the islands of the South Pacific. In other cases, species distributions may have been deliberately modified by human beings. The Polynesians in the South Pacific intentionally moved the kumara (sweet potato) to islands in that region to provide the population with a new food crop.
The relocation of species by humans (and more recently the imposition of restrictions on movement by way of national controls and world conventions) has been primarily for economic reasons and for environmental protection. For example, humans introduced Sitka spruce trees into Scotland and England from North America to use them as a timber crop. Similarly the Monterey pine tree was introduced into New Zealand in the nineteenth century from California and has become the most widely used species in the timber production industry in that country. The potato has been carried from its native home in the high Andes of South America, modified and developed into many varieties, and transported around the world because it can be used as a food crop. The plant formerly known as the Chinese gooseberry was relocated from its native China to New Zealand where an industry was established around the renamed kiwifruit.
We have extended the distribution of some species because of certain useful traits that make the species desirable beyond their former known range For example, willows have extensive root systems, can grow relatively quickly, and are now used in several countries worldwide to stabilize river margins as a flood protection measure. The distribution of willows has therefore been influenced considerably by human use in river bank management.The effects of introduced species can be many and varied and can include effects on the distribution of other species. For example, the North American gray squirrel was introduced into England and has now largely displaced the native red squirrel. The accidental introduction of organisms to new areas may have major pest implications. The South African bronze butterfly, the larva (immature insect forms) of which feed on buds and other parts of geraniums and similar flowers, was accidentally introduced into the Balearic Islands via imported geraniums. In its native South Africa, the distribution and abundance of the butterfly are affected in part by a native wasp that parasitizes (feeds on) the larvae. In the absence of the parasite wasp on the Balearic Islands off the coast of Spain, the butterfly has now spread to mainland Spain where its rapid spread has been accentuated by trade in garden plants and modem transport. The species has become a major pest due to the lack of a natural predator and is now causing great problems for the horticultural industry in Spain.
Human-driven changes in the distribution of some species may result in hybridization (interbreeding) with other species and so have a genetic effect. For example, the North American cord grass was accidentally introduced to the south coast of England in the early nineteenth
century. It hybridized with the European cord grass and resulted in the production of a new species,which in this case is also a major pest plant of estuaries in England where it became dominant and extensive Information about a species distribution (prior to human modification) maybe applied in pest control programs for the introduced species. Studies of the species in its native habitat may yield information about the factors that limit or influence its distribution and population dynamics. That information may then be applied in the development of strategies to contain and control the spread of pest species. For example, information about the role of the parasitic wasp in the ecology of the bronze butterfly may be utilized in the process of finding control strategies for that species on mainland Spain.
1.Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information. (Biologists, who commonly study the distribution of pi ant and animal species in different environments—their biogeography—strive to develop interpretations or explanations of the patterns of species distribution, but these may be incorrect if the effects of human beings are not taken into consideration.)
 
    托福TPO阅读49题目（第二篇）：
A. In biogeography it is common to consider and study the effects of plant and animal species as they are distributed within environments where humans live.
B. Biologists who study environments in which pi ants and animals are distributed have arrived at interpretations or explanations for how species succeed, but these may not be correct.
C. To understand plant and animal distribution patterns correctly, biologists must consider the role of hum an beings in the biogeography of species
D. It is common for biologists who try to understand the effects of humans on their environments to be incorrect in their explanations of certain distribution patterns of plants and animals.
2.In paragraph 1，the author makes the point that the relocations of rats and the kumara to new environments differed in
A. whether or not humans planned to transfer these species to a new environment
B. how far these species had to be transported to arrive at the new environment
C. how difficult it was for these species to become established in the new environment
D. whether or not these species succeeded in the new environment
3.The word "formerly" in the passage is closest in meaning to
A. commonly
B. previously
C. officially
D. interestingly
4.In paragraph 2，the author mentions Chinese gooseberries and the Monterey pine in order to
A. contrast two plant species transplanted for different reasons
B. demonstrate how two extremely different species adapt to a similar environment in New Zealand
C. offer evidence that newly introduced species can have unintended positive effects on the environment
D. provide examples of species moved for economic purposes
5.The word "desirable" in the passage is closest in meaning to
A. easy to spread
B. quick to establish
C. wanted
D. practical
6. The word "relatively” in the passage is closest in meaning to
A. comparatively
B.surprisingly
C. extremely
D.at times
7.According to paragraph 3. why are willows a species that are now found in different countries worldwide?
A. They adapt easily to a variety of environments.
B. They have characteristics that make them useful in preserving river banks during floods.
C. They have a root system that allows them to reproduce easily and live long.
D. They require little care or management from humans.
8.The word "accentuated" in the passage is closest in meaning to
A.controlled
B.intensified
C.explained
D.restricted
9.What can be inferred from paragraph 4 about geraniums in South Africa as compared to geraniums in Spain and the Balearic Islands?
A. The structural parts and buds of geraniums in South Africa differ from those of geraniums in Spain and the Balearic Islands.
B. Compared to the geraniums in Spain, the ones in South Africa are less likely to have bronze butterfly larvae as a pest
C. Geraniums are less important to the horticulture industry in South Africa than they are to the horticultural industries tries of Spain and the Balearic Islands.
D. Geraniums in South Africa ire traded more than the geraniums in Spain and the Balearic Islands are.
10. According to paragraph 4, why did the South African bronze butterfly become a major pest in Spain?
A. Spain has a greater number of flowers for the butterflies to feed on
B. The butterfly's larvae reach maturity more quickly in Spain than they do elsewhere.
C. There are no natural predators of bronze butterfly larvae in Spain
D. The species of geranium that is found in Spain is a more delicate garden plant and easier for pests to consume
11. Paragraph 4 supports which of the following statement about the South African bronze butterfly?
A. It was deliberately introduced into two new environments at the same time
B. Its spread on mainland Spain had a significant economic impact
C. It changed its parasitizing behavior when it adapted to new environments
D. Its presence on mainland Spain and the Balearic Islands caused other insect populations to increase
12. Paragraph 6 returns to a discussion of the bronze buttery in order to
A.demonstrate that information about species in their native habitat can be applied to controlling their spread in new habitats
B.emphasize the negative effects of parastic wasps on butterflies in general
C.further support the claim that the bronze butterfly was accidentally introduced to mainland Spain
D.conclude by recommending the development of careful pest control strategies so that the ecology is not damaged
13.Look at the four squares [■] that indicate where the following sentence could be added to the passage.Its presence there helps control the bronze butterfly population.Where would the sentence best fit? Click on a square [■] to add the sentence to the passage.The effects of introduced species can be many and varied and can include effects on the distribution of other species. For example, the North American gray squirrel was introduced into England and has now largely displaced the native red squirrel. The accidental introduction of
organisms to new areas may have major pest implications. ■The South African bronze butterfly, the larva (immature insect forms) of which feed on buds and other parts of geraniums and similar flowers, was accidentally introduced into the Balearic Islands via imported geraniums. ■In its native South Africa, the distribution and abundance of the butterfly are affected in part by a native wasp that parasitizes (feeds on) the larvae. ■ In the absence of the parasite wasp on the Balearic Islands off the coast of Spain, the butterfly has now spread to mainland Spain where its rapid spread has been accentuated by trade in garden plants and modem transport. ■The species has become a major pest due to the lack of a natural predator and is now causing great problems for the horticultural industry in Spain.
14. A variety of factors, including human activity, can affect the distribution of species:
Answer Choices
1.Research has shown that the biogeography of species can change even without human interference as can be seen In the wide distribution of willows along a wide range of river banks.
2.Introducing a species to a new environment can have unintended consequences such as those that occurred when a butterfly was relocated to an environment that lacked its natural predator.
3.The success of relocating two species together depends on how they help each other survive in a new environment as demonstrated by the South African bronze butterfly and geraniums.
4.The study of the relocations of certain species to new habitats has been difficult because it is not always clear if the relocations were natural or caused by humans.
5.Humans have relocated species for a variety of reasons, including obtaining new food sources,creating new industries, and taking advantage of the characteristics of certain species
6.Understanding the distribution of a species in its native habitat can be useful in controlling Its spread as a pest in Its new habitat.
 
托福TPO阅读49原文（第三篇）-Newspaper in Western Europe
By the eighteenth century, newspapers had become firmly established as a means of spreading news of European and world affairs, as well as of local concerns, within European society. One of the first true newspapers was the Dutch paper Nieuwe Tidingen It began publication in the early seventeenth century at about the same time that the overseas trading company called the Dutch East India Company was formed The same ships that brought goods back from abroad brought news of the world, too.
Dutch publishers had an advantage over many other publishers around Europe because the Netherlands’ highly decentralized political system made its censorship laws very difficult to enforce Throughout Europe in the seventeenth century, governments began recognizing the revolutionary potential of the free press and began requiring licenses of newspapers—to control who was able to publish news Another tactic, in France and elsewhere on the continent from the 1630s onward, was for governments to sponsor official newspapers. These state publications met the increasing demand for news but always supported the government’s views of the events of the day
By the eighteenth century, new conditions allowed newspapers to flourish as never before First,demand for news increased as Europe’s commercial and political interests spread around the globe—merchants in London, Liverpool，or Glasgow, for example, came to depend on early news of Caribbean harvests and gains and losses in colonial wars Europe's growing commercial strength also increased distribution networks for newspapers. There were more and better roads, and more vehicles could deliver newspapers in cities and convey them to outlying towns Newspaper publishers made use of the many new sites where the public expected to read, as newspapers were delivered to cafes and sold or delivered by booksellers.
Second, many European states had established effective postal systems by the eighteenth century.It was through the mail that readers outside major cities and their environs—and virtually all readers in areas where press censorship was exercised firmly— received their newspapers. One of the most successful newspapers in Europe was a French-language paper (one of the many known as La Gazette,) published in Leiden, in the Netherlands, which boasted a wide readership in France and among elites throughout Europe.
Finally, press censorship faltered in one of the most important markets for news—England— at the turn of the eighteenth century after 1688. debate raged about whether the Parliament or the Crown had the right to control the press, and in the confusion the press flourished. The emergence of political parties further hampered control of the press because political decisions in Parliament now always involved compromise, and many members believed that an active press was useful to that process. British government’s control of the press was reduced to taxing newspapers, a tactic that drove some papers out of business.
Eighteenth-century newspapers were modest products by modern Western standards. Many were published only once or twice a week instead of every day, in editions of only a few thousand copies. Each newspaper was generally only four pages long. Illustrations were rare，and headlines had not yet been invented. Hand-operated wooden presses were used to print the papers, just as they had been used to print pamphlets and books since the invention of printing in the fifteenth century.
Yet these newspapers had a dramatic impact on their reading public Regular production of newspapers (especially of many competing newspapers) meant that news was presented to the public at regular intervals and in manageable amounts. Even strange and threatening news from around the world became increasingly easy for readers to absorb and interpret Newspaper readers also felt themselves part of the public life about which they were reading This was true partly because newspapers, available in public reading rooms and in cafes, were one kind of reading that occupied an increasing self-aware and literate audience. Newspapers also were uniquely responsive to their readers. They began to carry advertisements, which both produced revenue for papers and widened readers' exposure to their own communities. Even more important was the inauguration of letters to the editor in which readers expressed their opinions about events Newspapers thus became venues for the often rapid exchange of news and opinions.
 
    托福TPO阅读49题目（第三篇）：
1.According to paragraph 1，what was true about the Dutch paper Nieuwe Tijdingen ?
A.It reported news mainly about ships and trade goods
B.It was established in the eighteenth century
C.It was among the first real newspapers in Europe.
D.It was published by an overseas trading company.
2.Paragraph 2 suggests that the main reason why governments began to license newspapers was
A.to make sure that newspapers were of high quality
B.to provide their countries1 publishers with an advantage over other European publishers
C.to reduce competition among government-sponsored newspapers
D.to help control the public's attitudes about the news
3.According to paragraph 2, what was true about official government newspapers?
A.They made censorship laws more difficult to enforce
B.They expanded the revolutionary potential of the press
C.They appeared first in the Netherlands,
D.They always agreed with the government's opinion.
4.According to paragraph 3, why did demand for news increase in the eighteenth century?
A.People wanted to read about the new books being sold by booksellers
B.Governments wanted to make sure their colonies were being governed efficiently.
C.Merchants needed to know how their businesses would be affected by events in other countries.
D.Owners of cafes needed to predict how foreign harvests might affect food prices
5.The word “exercised” in the passage is closet in meaning to
A.criticized
B.rejected
C.applied
D.defended
6.In paragraph 4, why does the author mention a French language paper that was published in Leiden?
A.To show that the most successful newspapers in Europe tended to be French-language newspapers
B.To illustrate the important role played by the mail in the distinction of newspapers
C.To provide evidence that newspapers were being read by the elites of Europe
D.To establish that the Netherlands had one of the most effective postal systems in Europe
7. The word "emergence” in the passage is closest in meaning to
A. influence
B. activity
C. rise
D. success
8. The word "tactic” in the passage is closest in meaning to
A. strategy
B. situation
C. requirement
D. reason
9. According to paragraph 5, many members of Parliament held which of the following views about the English press?
A. It had the effect of increasing tensions between Parliament and the monarchy
B. It created pressure that encouraged political opponents to reach agreement
C. It helped create the confusion that led to the emergence of political parties.
D. It could be more effectively controlled by compromise than by taxing newspapers
10. According to paragraph 6 ， all of the following are true of eighteenth- century newspapers
EXCEPT
A. They usually were published no more than twice a week
B. They generally consisted of four pages
C. They included numerous illustrations.
D. They had no headlines
11. The word "thus" in the passage is closest in meaning to
A. consequently
B. regularly
C. in addition
D. soon
12. According to paragraph 7 ， newspapers had all of the following effects on their readers
A. They found it easier to understand news from other countries
B. They became more successful in business than those who did not read newspapers
C. They became better connected to their local communities.
D. They could write about their own opinions on current events
13.Look at the four squares ■ that indicate where the following sentence could be added to the passage: ,
And even when it was possible to apply laws limiting speech, authorities were reluctant to do so because of the growing economic importance of the commercial book market.Dutch publishers had an advantage over many other publishers around Europe because the Netherlands’ highly decentralized political system made its censorship laws very difficult to enforce. ■ Throughout Europe in the seventeenth century, governments began recognizing the revolutionary potential of the free press and began requiring licenses of newspapers—to control who was able to publish news. ■Another tactic, in France and elsewhere on the continent from the 1630s onward, was for governments to sponsor official newspapers.■These state publications met the increasing demand for news but always supported the government's views of the events of the day. ■
14. Summary:By the eighteenth century, newspapers had become established as a means of spreading news of European affairs within European society.
A.Governments tried to control what news got published by sponsoring official newspapers,taxing publishers, requiring newspapers to be licensed, and instituting press-censorship laws.
B.England was the most Important market for news, but disruptions caused by conflict over how the government should control the press resulted in many British newspapers being driven out of business.
C.Censorship laws were established and enforced differently across Europe because of differences in the political systems of the various countries.
D.Europe's expanding commercial and political interests led to increased demand for news and also to improved systems for distributing newspapers,
E.Although eighteenth-century newspapers were modest by modern standards, they made current events accessible to the reading public and facilitated the rapid exchange of news and opinions.
F.Newspapers' regular presentation of strange and threatening news from around the world had the effect of making their readers feel more closely connected to their own local communities.