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We may all like to consider ourselves free spirits. But a study of the traces left by 50,000 cellphone users over three months has conclusively proved that the truth is otherwise. "We are all in one way or another boring," says Alhert-László Barabási at the Center for Complex Network Research at Northeastern University in Boston, who co-wrote the study. "Spontaneous individuals are largely absent from the population." Barabási and colleagues used three months’ worth of data from a cellphone network to track the cellphone towers each person’s phone connected to each hour of the day, revealing their approximate location. They conclude that regardless of whether a person typically remains close to home or roams far and wide, their movements are theoretically predictable as much as 93 per cent of the time. Surprisingly, the cellphone data showed that individuals’movements were more or less as predictable at week ends as on weekdays, suggesting that routine is rooted in human nature rather than being an effect of work patterns. The cellphone records were processed to identify the most visited locations for each user. Then the probability of finding a given user at his or her most visited locations at each hour through the day was calculated. People were to be found in their most visited location for any given hour 70 per cent of the time. Not surprisingly, the figure increased at night, and decreased at lunchtime and in the early evening, when most people were returning home from work. The team analysed the randomness(随意的) of people’s traces to show it was theoretically possible to predict the average person’s whereabouts as much as 93 per cent of the time. "Say your routine movement is from home to the coffee shop to work: if you are at home and then go to the coffee shop it’s easy for me to predict that you are going to work," says co-author Nicholas Blumm. This predictability was not much affected by differences in age, gender, language spoken or whether a person lived in a rural or urban setting. What did the cellphone data show about "routine"
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Passage One What does the speaker tell us about important decision-making in the US
公安机关是政府的一个职能部门，但不同于一般行政机关；人民警察是国家公务人员，但又不同于政府其他部门的公务员。因此，对人民警察的素质和职业道德必须有更高更严的要求。( )
中国共产党对公安机关的绝对领导是无条件的和全面的，但不是直接的。 ( )
Opportunists and Competitors A) Growth, reproduction, and daily metabolism all require an organism to expend energy. The expenditure of energy is essentially a process of budgeting, just as finances are budgeted. If all of one’s money is spent on clothes, there may be none left to buy food or go to the movies. Similarly, a plant or animal cannot squander all its energy on growing a big body if none would be left over for reproduction, for this is the surest way to extinction. B) All organisms, therefore, allocate energy to growth, reproduction, maintenance, and storage. No choice is involved; this allocation comes as part of the genetic package from the parents. Maintenance for a given body design of an organism is relatively constant. Storage is important, but ultimately that energy will be used for maintenance, reproduction, or growth. Therefore the principal differences in energy allocation are likely to be between growth and reproduction. C) Almost all of an organism’s energy can be diverted to reproduction, with very little allocated to building the body. Organisms at this extreme are "opportunists". At the other extreme are "competitors", almost all of whose resources are invested in building a huge body, with a bare minimum allocated to reproduction. D) Dandelions are good examples of opportunists. Their seed heads raised just high enough above the ground to catch the wind, the plants are no bigger than they need be, their stems are hollow, and all the rigidity comes from their water content. Thus, a minimum investment has been made in the body that becomes a platform for seed dispersal. These very short-lived plants reproduce prolifically; that is to say they provide a constant rain of seed in the neighborhood of parent plants. E) A new plant will spring up wherever a seed falls on a suitable soil surface, but because they do not build big bodies, they cannot compete with other plants for space, water, or sunlight. These plants are termed opportunists because they rely on their seeds’ falling into settings where competing plants have been removed by natural processes, such as along an eroding riverbank, on landslips, or where a tree falls and creates a gap in the forest canopy. F) Opportunists must constantly invade new areas to compensate for being displaced by more competitive species. Human landscapes of lawns, fields, or flowerbeds provide settings with bare soil and a lack of competitors that are perfect habitats for colonization by opportunists. Hence, many of the strongly opportunistic plants are the common weeds of fields and gardens. G) Because each individual is short-lived, the population of an opportunist species is likely to be adversely affected by drought, bad winters, or floods. If their population is tracked through time, it will be seen to be particularly unstable—soaring and plummeting in irregular cycles. H) The opposite of an opportunist is a competitor. These organisms tend to have big bodies, are long-lived, and spend relatively little effort each year on reproduction. I) An oak tree is a good example of a competitor. A massive oak claims its ground for 200 years or more, out-competing all other would-be canopy trees by casting a dense shade and drawing up any free water in the soil. The leaves of an oak tree taste foul because they are rich in tannins, a chemical that renders them distasteful or indigestible to many organisms. The tannins are part of the defense mechanism that is essential to longevity. J) Although oaks produce thousands of acorns, the investment in a crop of acorns is small compared with the energy spent on building leaves, trunk, and roots. Once an oak tree becomes established, it is likely to survive minor cycles of drought and even fire. A population of oaks is likely to be relatively stable through time, and its survival is likely to depend more on its ability to withstand the pressures of competition or predation than on its ability to take advantage of chance events. K) It should be noted, however, that the pure opportunist or pure competitor is rare in nature, as most species fall between the extremes of a continuum, exhibiting a blend of some opportunistic and some competitive characteristics. L) Oak wood has a density of about 0.75g/cm3, great strength and hardness, and is very resistant to insect and fungal attack because of its high tannin content. It also has very appealing grain markings, particularly when quarter-sawn. M) Oak planking was common on high status Viking longships in the 9th and 10th centuries. The wood was hewn (砍) from green logs, by axe and wedge, to produce radial planks, similar to quarter-sawn timber. Wide, quarter-sawn boards of oak have been prized since the Middle Ages for use in interior paneling of prestigious buildings such as the debating chamber of the House of Commons in London and in the construction of fine furniture. N) Oak wood, from Quercus robur and Quercus petraea, was used in Europe for the construction of ships until the 19th century, and was the principal timber used in the construction of European timber-framed buildings. Today oak Wood is still commonly used for furniture making and flooring, timber frame buildings, and for veneer production. Barrels in which wines, sherry, and spirits such as brandy, Scotch whisky and Bourbon whiskey are aged are made from European and American oak. The use of oak in wine can add many different dimensions to wine based on the type and style of the oak. Oak barrels, which may be charred before use, contribute to the colour, taste, and aroma of the contents, imparting a desirable oaky vanillin flavour to these drinks. The great dilemma for wine producers is to choose between French and American oak woods. French oaks (Quercus robur, Quercus petraea) give the wine greater refinement and are chosen for the best wines since they increase the price compared to those aged in American oak wood. American oak contributes greater texture and resistance to ageing, but produces more violent wine bouquets. Oak wood chips are used for smoking fish, meat, cheeses and other foods. O) Japanese oak is used in the making of professional drums from manufacturer Yamaha Drums. The higher density of oak gives the drum a brighter and louder tone compared to traditional chum materials such as maple and birch. In hill states of India, besides fuelwood and timber, the local people use oak wood for making agricultural implements. The leaves are used as fodder during lean period and bedding for livestock. If you want to find a good example of opportunists, dandelion is a good choice for research.
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