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1、【说明】3月精读团注定要载入史册啦！3月25日再次命中2篇文章！P4 P5 原题重现这样我们这期精读团P4 5 6 7 11都考过了目前还没有出现考过文章短期内重复的情况（不过大家密切关注最新考勤）之前答应大家如果325再重复就再补文章所以我们补2篇文章时间安排在3月31日下午3点，正好4月1日的同学可以考前听完真题附体可以3月25日也考了，这个就当大家的附体课吧P14 Habitat SelectionResearchers who study habitat selection have proposed various models for the process. Marine bio

2、logist Peter F. Sale hypothesized the existence of a simple mechanism of habitat selection in fish that is based on levels of exploratory behavior. Sense organs monitor specific stimuli in the environment and send a summation of pertinent stimuli back to central-nervous-system centers, which regulat

3、e the amount of exploration. As the constellation of cues approaches some optimum level, exploratory behavior ceases and the animal stays where it is.An alternative hypothesis is that an animal has a cognitive map of the ideal habitat and that its behavior is goal directed. However, working with a s

4、pecies of surgeonfish, Sale tested juveniles in laboratory tanks with various water depths and bottom covers under which fish could hide. Exploration time was least in the tank with shallow water and bottom cover and highest in the tank with shallow water and no bottom cover. In choice tests and fie

5、ld observations, most fish preferred shallow areas with bottom cover. Thus, Sale concluded, there is no need to suggest the inheritance of complex cognitive maps and goal-directed behaviors, rather, the animal simply moves around more in an unsuitable habitat and less in a suitable one.Sales model s

6、till does not explain how the animal “knows” what is suitable and what is not, or how stimuli from multiple cues are integrated. Nor does it explain the role of photoperiod (the duration of the animals daily exposure to sunlight) in the response of dark-eyed juncos to photographs of their natural ha

7、bitat. These wild-caught birds were presented a choice of viewing one of two 35-millimeter color slides showing different habitats. Birds kept in the lab under a winter photoperiod of nine hours of light and fifteen hours of darkness preferred (spent more time in front of) slides of their southern w

8、inter habitat. After day length was increased to fifteen hours of light and nine hours of darkness, the birds viewing preferences shifted to the northern summer habitat. Social cues may also affect choice of habitat. Large juncos (usually males) dominate smaller individuals (usually females and juve

9、niles) in wintering flocks. Biologist Ellen Ketterson explained the finding that females usually migrate farther south than males by hypothesizing that subordinate birds are forced to migrate farther to avoid competing with dominants. In their lab study, researchers E. Roberts and Peter Weigl found

10、that during the short days (stimulating winter), small subordinate juncos showed the strongest preference for winter scenes.Risk of predation and competition are other factors that may affect habitat use. Hairy-footed gerbils live in vegetated islands in a sea of sand in the Namib Desert of southern

11、 Africa. Habitat use was determined by tracks in the sand and by how quickly they gave up feeding at stations containing seeds mixed with sand. Gerbils preferred sites around bushes or grass clumps to open areas and were more active on new-Moon nights than on full-Moon nights. They also gave up feed

12、ing at seed trays sooner in open areas and on full-Moon nights. These differences were likely caused by greater risk of predation in open areas and when the Moon was full. When striped mice, a close competitor of the gerbil, were removed, gerbils increased foraging activity, especially in the grass

13、clumps.The immediate cues to which animals respond when selecting a habitat may not be the same as the ultimate factors that have brought about the evolution of the response. For example, the blue tit, a European bird, lives in oak woodlands where most of its preferred food is found. But the blue ti

14、t establishes its territory each year before leaves and caterpillars (its staple food) have even appeared, so it must be using some other cue, such as the shape of the trees, to select its habitat. In fact, we know little about the signals that animals respond to when choosing their habitat. And in

15、migratory species, it is not even clear when in the life cycle a choice of habitat is made. One study found that breeding sites may be selected in late summer or fall before migration, rather than in the spring, as is usually assumed.Paragraph 1The word “pertinent” in the passage is closet in meanin

16、g toimportantselectedstrongrelevantAccording to paragraph 1, all of the following are processes that occur during exploratory behavior EXCEPT:A favorable combination of cues are gathered.Sense organs detect and record stimuli in the surrounding area.Sense organs receive further directions from the c

17、entral nervous system.The central nervous system receives a summary of stimuli from the sense organs.The word “ceases” in the passage is closet in meaning tostopsdecreasessucceedsoccursParagraph 2In paragraph 2, why does the author discuss Sales research with a species of surgeonfish?To demonstrate

18、how animals distinguish suitable habitats from unsuitable onesTo give an example of an animal that shows little or no exploratory behavior during habitat selectionTo challenge the hypothesis that animals have complex cognitive maps of their ideal habitat that guide their habitat selectionTo provide

19、evidence that fish prefer areas that are shallow and have covering under which to hideParagraph 3The word “integrated” in the passage is closet in meaning tointerpretedproducedfoundcombinedAccording to paragraph 3, Sales model of habitat selection is unable to explain which of the following?Why dark

20、-eyed juncos interest in a particular habitat changes with the duration of daylight they are exposed toWhy the environment suitable for dark-eyed juncos in the winter differs from the environment suitable for them in the summerWhy only some species of animals respond to photographs of their natural

21、habitatsWhy birds studied in the lab behave differently than birds in the wild doParagraph 3 supports which of the following statements about dark-eyed juncos?The habitat preference of dark-eyed juncos changes with the amount of daylight present.Wild-caught dark-eyed juncos do not recognize photogra

22、phs of their own habitat.Dark-eyed juncos choose their habitat based on seasonal temperatures.Artificial light affects dark-eyed juncos choice of habitat differently than does natural sunlight.Paragraph 4According to paragraph 4, what reason has been suggested for why female juncos often migrate far

23、ther south than do male juncos?To avoid the colder temperatures farther northTo provide safer habitats for their juvenilesTo avoid having to compete with malesTo find habitats having the longest daysParagraph 5Risk of predation and competition are other factors that may affect habitat use. Hairy-foo

24、ted gerbils live in vegetated islands in a sea of sand in the Namib Desert of southern Africa. Habitat use was determined by tracks in the sand and by how quickly they gave up feeding at stations containing seeds mixed with sand. Gerbils preferred sites around bushes or grass clumps to open areas an

25、d were more active on new-Moon nights than on full-Moon nights. They also gave up feeding at seed trays sooner in open areas and on full-Moon nights. These differences were likely caused by greater risk of predation in open areas and when the Moon was full. When striped mice, a close competitor of t

26、he gerbil, were removed, gerbils increased foraging activity, especially in the grass clumps.According to paragraph 5, why do hairy-footed gerbils prefer to feed in bushes and grass clumps?There is more food available there.There is less competition there from striped mice.There is more shade there

27、from the heat of the desert.There is less danger there of being harmed by a predator.Paragraph 6According to paragraph 6, which of the following is true about habitat selection by the blue tit?It selects a habitat having the tallest trees.It selects a habitat where there are no caterpillars to eat t

28、he leaves.It selects its territory each year in spring.It selects its habitat before its preferred food appears in the area.Paragraph 6 supports which of the following statements about scientists knowledge of habitat selection?Scientists have successfully identified most of the immediate factors tha

29、t animals respond to in choosing their habitats.Scientists have determined the seasons in which most animal species choose their habitats.Scientists know that evolution has led animals to ignore cues in their environment when choosing habitats.Scientists still have much to learn about the cues to wh

30、ich animals respond in choosing their habitats.Paragraphs 3 and 4Sales model still does not explain how the animal “knows” what is suitable and what is not, or how stimuli from multiple cues are integrated. Nor does it explain the role of photoperiod (the duration of the animals daily exposure to su

31、nlight) in the response of dark-eyed juncos to photographs of their natural habitat. These wild-caught birds were presented a choice of viewing one of two 35-millimeter color slides showing different habitats. Birds kept in the lab under a winter photoperiod of nine hours of light and fifteen hours

32、of darkness preferred (spent more time in front of) slides of their southern winter habitat. After day length was increased to fifteen hours of light and nine hours of darkness, the birds viewing preferences shifted to the northern summer habitat. Social cues may also affect choice of habitat. Large

33、 juncos (usually males) dominate smaller individuals (usually females and juveniles) in wintering flocks. Biologist Ellen Ketterson explained the finding that females usually migrate farther south than males by hypothesizing that subordinate birds are forced to migrate farther to avoid competing wit

34、h dominants. In their lab study, researchers E. Roberts and Peter Weigl found that during the short days (stimulating winter), small subordinate juncos showed the strongest preference for winter scenes.Look at the four squares that indicate where the following sentence could be added to the passage.

35、However, photoperiod is not the only factor in the habitat selection of this bird species.Where would the sentence best fit? Click on a square to add the sentence to the passage.Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecti

36、ng the THREE answer choices that express the most important ideas in the passage. Some answer choices 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.Researchers who study habitat selecti

37、on among animals have proposed various models for the process.Peter F. Sale argued against the hypothesis that animals have cognitive maps of their ideal habitat by demonstrating that animals explore less in suitable habitats than in unsuitable ones.Animals kept in the lab easily recognized images o

38、f their natural habitats during different seasons of the year.Researchers have demonstrated that migratory species of birds select their breeding habitats at a point in their life cycle when they are ready to reproduce.Peter F. Sales model of habitat selection explained how animals distinguish suita

39、ble habitats from unsuitable ones as they integrate stimuli from multiple cues in the environment.Laboratory experiments and field observations showed that day length, dominance relation within species, risk of predation, and competition for food play a role in habitat selection.The fundamental elem

40、ents that determine habitat selection may differ from the immediate cues to which the animals respond.P15 Urban Development in the United States in the 19th CenturyIn discussing the growth of cities in the United States in the nineteenth century, one cannot really use the term “urban planning,” as i

41、t suggests modern concerns for spatial and service organization which, in most instances, did not exist before the planning revolution called the City Beautiful Movement that began in the 1890s. While there certainly were urban areas that were “planned” in the comprehensive contemporary sense of the

42、 word before that date, most notably Washington, D.C. , these were the exception. Most “planning” in the nineteenth century was limited to areas much smaller than a city and was closely associated with developers trying to make a profit from a piece of land. Even when these small-scale plans were we

43、ll designed, the developers made only those improvements that were absolutely necessary to attract the wealthy segment of the market. Indeed, it was the absence of true urban planning that allowed other factors to play such an important role in shaping the nineteenth century American city.Three forc

44、es particularly affected the configuration of urban and suburban areas in the nineteenth century: economics, transportation technology, and demographics. Added to these was the characteristic American preference both for independent living, usually associated with having an individual, free-standing

45、 home for ones family, and for rural living. Economics affected urbanization in two ways. First, economic considerations influenced location decisions for business and industry, which often preempted choice sites. Second, industrial growth generated higher incomes for large segments of the populatio

46、n, which in turn provided more money for larger homes and commuter transportation. Related to economics (since costs to individuals always played a role) were improvements in transportation, from the first horse-drawn buses of the 1820s to electrified street railways at the end of the century. Each

47、transport innovation extended the distance that a person could reasonably travel as a commuter or shopper, while constant system improvements and increased ridership lessened costs. Demographic patterns also affected urbanization in two ways: first, urban populations grew steadily throughout the cen

48、tury due to immigration from rural areas, principally by those seeking factory work, and emigration from abroad. Therefore cities expanded as new housing had to be provided. Secondly, at the same time that new residents were surging into cities, many urbanites, particularly those of the middle class

49、es, began to leave. While a preference for rural living explained part of this exodus, it was also due to the perception that various urban problems were becoming worse.Many nineteenth-century urban problems were those that continue to plague cities todaycrime, pollution, noisebut others were the di

50、rect result of lack of planning and regulation, such as threat of fire, poor sanitation, and shoddy building construction. Fire was a significant problem in urban areas of North America from the time of the first European settlement. Construction with combustible materials coupled with close placeme

51、nt of buildings and the use of open flames in heating, cooking, and lighting meant that the potential for raging fires was ever present. Lack of sanitation, and the ensuing public health problems it created, was a more constant, if less dramatic, urban issue it was not until the 1860s that any serio

52、us, concerted effort was made to develop proper systems for water delivery and sewage removal. In spite of remarkable strides made in the 1870s and 1880s by the newly established profession of sanitary engineering, the common nineteenth-century pattern of individual unprofessionally planned and inst

53、alled cesspools (underground tanks for holding household sewage) continued. This led to water contamination and the spread of disease by rodents and insects. Problems of the fire and poor sanitation were inextricably linked with the last major urban problem of the nineteenth centurylack of coordinat

54、ion in the physical expansion of cities and their infrastructure systems (systems for providing services such as water, gas, electricity, and sewage). Typically, development was both unplanned and unrestricted, with landowners making all choices of lot size, services, and street arrangement based on

55、ly on their individual needs in the marketplace. Distortions of streets and abrupt changes in the distance of houses from the street in urban areas, which so clearly delineate where one development ended and another began, were just the most obvious problems that this lack of coordination created. P

56、aragraph 1Which 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 Understanding the growth of cities in nineteenth-century America requires recognizing

57、how the City Beautiful Movement of the 1890s changed “urban planning.” For the most part, there was no “urban planning”, as that term is understood today, before the beginning of the City Beautiful Movement in the 1890s. Concerns for spatial and service organization had little impact on the growth o

58、f cities before the 1890s when the City Beautiful Movement began.The growth of cities in nineteenth-century America resulted in the creation of the City Beautiful Movement in the 1890s and the rise of the term “urban planning.”According to paragraph 1, Washington. D.C. was a typical nineteenth-centu

59、ry American citya city that was planned in separate sections by land developersthe very first city in America to be described as “planned”one of the few cases of true urban planning in America before the 1890sSelect the TWO answer choices that, according to paragraph 1, best describe most urban plan

60、s in the nineteenth century. To receive credit, you must select TWO answers.They were created to profit land developers.They typically affected only part of a city rather than the whole city.Their success sometimes directly led to other necessary improvements in cities.They were carefully reviewed b