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Rain forests Tropical rainforests are the most diverse ecosystem (生态系统) on Earth, and also the oldest. Today, tropical rainforests cover only 6 percent of the Earth’s ground surface, but they are home to over half of the planet’s plant and animal species.What Is a Rainforest Generally speaking, a rainforest is an environment that receives high rainfall and is dominated by tall trees. A wide range of ecosystems fall into this category, of course. But most of the time when people talk about rainforests, they mean the tropical rainforests located near the equator. These forests receive between 160 and 400 inches of rain per year. The total annual rainfall is spread pretty evenly throughout the year, and the temperature rarely dips below 60 degrees Fahrenheit. This steady climate is due to the position of rainforests on the globe. Because of the orientation of the Earth’s axis, the Northern and Southern hemispheres each spend part of the year tilted away from the sun. Since rainforests are at the middle of the globe, located near the equator, they arc not especially affected by this change. They receive nearly the same amount of sunlight, and therefore heat, all year. Consequently, the weather in these regions remains fairly constant. The consistently wet, warm weather and ample sunlight give plant life everything it needs to thrive. Trees have the resources to grow to tremendous heights, and they live for hundreds, even thousands, of years. These giants, which reach 60 to 150 ft in the air, form the basic structure of the rainforest. Their top branches spread wide in order to capture maximum sunlight. This creates a thick canopy (树冠) level at the top of the forest, with thinner greenery levels underneath. Some large trees grow so tall that they even tower over the canopy layer. As you go lower, down into the rainforest, you find less and less greenery. The forest floor is made up of moss, fungi, and decaying plant matter that has fallen from the upper layers. The reason for this decrease in greenery is very simple the overabundance of plants gathering sunlight at the top of the forest blocks most sunlight from reaching the bottom of the forest, making it difficult for robust plants to thrive.The Forest for the Trees The ample sunlight and extremely wet climate of many tropical areas encourage the growth of towering trees with wide canopies. This thick top layer of the rainforest dictates the lives of all other plants in the forest. New tree seedlings rarely survive to make it to the top unless some older trees die, creating a "hole" in the canopy. When this happens, all of the seedlings on the ground level compete intensely to reach the sunlight. Many plant species reach the top of the forest by climbing the tall trees. It is much easier to ascend this way, because the plant doesn’t have to form its own supporting structure. Some plant species, called epiphytes, grow directly on the surface of the giant trees. These plants, which include a variety of orchids and ferns, make up much of the understory, the layer of the rainforest right below the canopy. Epiphytes are close enough to the top to receive adequate light, and the runoff from the canopy layer provides all the water and nutrients(养分)they need, which is important since they don’t have access to the nutrients in the ground. Stranglers and Buttresses Some epiphytes eventually develop into stranglers. They grow long, thick roots that extend down the tree trunk into the ground. As they continue to grow, the roots form a sort of web structure all around the tree. At the same time, the strangler plant’s branches extend upward, spreading out into the canopy. Eventually, the strangler may block so much light from above, and absorb such a high percentage of nutrients from the ground below, that the host tree dies. Competition over nutrients is almost as intense as competition for light. The excessive rainfall rapidly dissolves nutrients in the soil making it relatively infertile except at the top layers. For this reason, rainforest tree roots grow outward to cover a wider area, rather than downward to lower levels. This makes rainforest trees somewhat unstable, since they don’t have very strong anchors in the ground. Some trees compensate for this by growing natural buttresses. These buttresses are basically tree trunks that extend out from the side of the tree and clown to the ground, giving the tree additional support. Rainforest trees are dependent on bacteria that are continually producing nutrients in the ground. Rainforest bacteria and trees have a very close, symbiotic (共生的) relationship. The trees provide the bacteria with food, in the form of fallen leaves and other material, and the bacteria break this material down into the nutrients that the trees need to survive. One of the most remarkable things about rainforest plant life is its diversity. The temperate rainforests of the Pacific Northwest are mainly composed of a dozen or so tree species. A tropical rainforest, on the other hand, might have 300 distinct tree species.All Creatures, Great and Small Rainforests are home to the majority of animal species in the world. And a great number of species who now live in other environments, including humans, originally inhabited the rainforests. Researchers estimate that in a large rainforest area, there may be more than 10 million different animal species. Most of these species have adapted for life in the upper levels of the rainforest, where food is most plentiful. Insects, which can easily climb or fly from tree to tree, make up the largest group (ants are the most abundant animal in the rainforest). Insect species have a highly symbiotic relationship with the plant life in a rainforest. The insects move from plant to plant, enjoying the wealth of food provided there. As they travel, the insects may pick up the plants’ seeds, dropping them some distance away. This helps to disperse the population of the plant species over a larger area. The numerous birds of the rainforest also play a major part in seed dispersal. When they eat fruit from a plant, the seeds pass through their digestive system. By the time they excrete (排泄) the seeds, the birds may have flown many miles away from the fruit-bearing tree. There are also a large number of reptiles and mammals in the rainforest. Since the weather is so hot and humid during the day, most rainforest mammals are active only at night, dusk or dawn. The many rainforest bat species are especially well adapted for this lifestyle. Using their sonar, bats navigate easily through the mass of trees in the rainforest, feeding on insects and fruit. While most rainforest species spend their lives in the trees, there is also a lot of life on the forest floor. Great apes, wild pigs, big cats and even elephants can all be found in rainforests. There are a number of people who live in the rainforests, as well. These tribes--which, up until recently, numbered in the thousands--are being forced out of the rainforests at an alarming rate because of deforestation.Deforestation In the past hundred years, humans have begun destroying rainforests at an alarming rate. Today, roughly 1.5 acres of rainforest are destroyed every second. People are cutting down the rainforests in pursuit of three major resources: · land for crops · lumber for paper and other wood products · land for livestock pastures In the current economy, people obviously have a need for all of these resources. But almost all experts agree that, over time, we will suffer much more from the destruction of the rainforests than we will benefit. The world’s rainforests are an extremely valuable natural resource, to be sure, but not for their lumber or their land. They are the main cradle of life on Earth, and they hold millions of unique life forms that we have yet to discover. Destroying the rainforests is comparable to destroying an unknown planet we have no idea what we’re losing. If deforestation continues at its current rate, the world’s tropical rainforests will be wiped out within 40 years. As we are still ignorant of millions of unique life forms in the rainforest, deforestation can be compared to the destruction of ______.
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Be very wary of opinions that flatter your self-esteem. Both men and women, nine times out of ten, are firmly convinced of the superior excellence of their own sex. There is abundant evidence on both sides. If you are a man, you can point out that most poets and men of science are male; If you are a woman, you can retort that so are most criminals. The question is inherently insoluble, but self-esteem conceals this from most people. We are all, whatever part of the world we come from, persuaded that our own nation is superior to all others... The only way I know of dealing with this general human conceit is to remind ourselves that man is a brief episode in the life of a small planet in a little corner of the universe, and that for what we know, other parts of the cosmos may contain beings as superior to ourselves as we are to jelly-fish.
America is a country that now sits atop the cherished myth that work provides rewards, that working people can support their families. It’s a myth that has become so divorced from reality that it might as well begin with the words "Once upon a time". Today 1.6 million New Yorkers suffer from "food insecurity", which is a fancy way of saying they don’t have enough to eat. Some are the people who come in at night and clean the skyscrapers that glitter along the river. Some pour coffee and take care of the aged parents of the people who live in those buildings. The American Dream for the well-to-do grows from the bowed backs of the working poor, who too often have to choose between groceries and rent. In a new book called "The Betrayal of Work", Beth Shulman says that even in the booming 1990s one out of every four American workers made less than $8. 70 an hour, an income equal to the government’s poverty level for a family of four. Many, if not most, of these workers had no health care, sick pay or retirement provisions. We ease our consciences, Shulman writes, by describing these people as "low skilled", as though they’re not important or intelligent enough to deserve more. But Iow-skilled workers today are better educated than ever before, and they constitute the linchpin (SYNC) of American industry. When politicians crow (得意洋洋地说) that happy days are here again because jobs are on the rise, it’s these jobs they’re really talking about. Five of the 10 occupations expected to grow big in the next decade are in the lowest-paying job groups. And before we sit back and decide that’s just the way it; is, it’s instructive to consider the rest of the world. While the bottom 10 percent of American workers earn just 37 percent of our average wage, their counterparts in other industrialized countries earn upwards of 60 percent. And those are countries that provide health care and child care, which eases the economic pinch considerably. Almost 40 years ago, when Lyndon Johnson declared war on poverty, a family with a car and a house in the suburbs felt prosperous. Today that same family may well feel poor, overwhelmed by credit card debt, a second mortgage and the cost of the stuff that has become the backbone of American life. When the middle Class feels poor, the poor have little chance for change, or even recognition. Some Americans try to make themselves feel less guilty by attributing the poverty of the working people to ______.
TEXT C "Winners" Winners have different potentials. Achievement is not the most important thing, authenticity is. The authentic person experiences the reality of himself by knowing himself, being himself, and becoming a credible, responsive person. He actualizes his own unprecedented uniqueness and appreciates the uniqueness of others. A winner is not afraid to do his own thinking and to use his own knowledge. He can separate facts from opinion and doesn’t pretend to have all the answers. He listens to others, evaluates what they say, but comes to his own conclusions. While he can admire and respect other people, he is not totally defined, demolished, bound, or awed by them. A winner can be spontaneous. He does not have to respond in predetermined, rigid ways. He can change his plans when the situation calls for it. A winner has a zest for life. He enjoys work, play, food, other people, sex, and the world of nature. Without guilt, he enjoys his own accomplishments. Without envy he enjoys the accomplishments of others. Although a winner can freely enjoy himself, he can also postpone enjoyment. He can discipline himself in the present to enhance his enjoyment in the future. He is not afraid to go after what he wants but does so in appropriate ways. He does not get his security by controlling others. He does not set himself up to lose. A winner cares about the world and its peoples. He is not isolated from the general problems of society. He is concerned, compassionate, and committed to improving the quality of life. Even in the face of national and international adversity, he does not see himself as totally powerless. He does what he can to make the world a better place. "Losers" Although people are born to win, they are also born helpless and totally dependent on their environment. Winners successfully make the transition from total helplessness to independence and then to interdependence. Losers do not. Somewhere along the line they begin to avoid becoming self-responsible. As we have noted, few people are total winners or losers. Most of them are winners in some areas of their lives and losers in others. Their winning or losing is influenced by what happens to them in childhood. A lack of response to dependency needs, poor nutrition, brutality, unhappy relationships, disease, continuing disappointments, inadequate physical care, and traumatic events are among the many experiences that contribute to making people losers. Such experiences interrupt, deter, or prevent the normal progress toward autonomy and self-actualization. To cope with negative experiences a child learns to manipulate himself and others. These manipulative techniques are hard to give up later in life and often become set patterns. A winner works to shed them. A loser hangs on to them. A loser represses his capacity to express spontaneously and appropriately his full range of possible behaviour. He may be unaware of other options for his life if the path he chooses goes nowhere. He is afraid to try new things. He maintains his own status quo. He is a repeater. He repeats not only his own mistakes but often those of his family and culture also. A loser has difficulty giving and receiving affection. He does not enter into intimate, honest, direct relationships with others. Instead, he tries to manipulate them into living up to his expectations and channels his energies into living up to their expectations. When a person wants to discover and change his "losing streak", when he wants to become more like the winner he was born to be, he can use gestalt-type experiments and transactional analysis to make change happen. These are two new, exciting, psychological approaches to human problems. The first was given new life by Dr. Frederick Peris; the second was developed by Dr. Eric Berne. Gestalt therapy is not new. However, its current popularity has grown very rapidly since it Was given new impetus and direction by Dr. Frederick Peris. Gestalt is a German word for which there is no exact English equivalent; it means, roughly, the forming of an organised, meaningful whole. Peris perceives many personalities as lacking wholeness, as being fragmented. He claims people are often aware of only parts of themselves rather than of the whole self. For example, a woman may not know or want to admit that sometimes she acts like her mother; a man may not know or admit that sometimes he wants to cry like a baby. The aim of gestalt therapy is to help one to become whole-to help the person become aware of, admit to, reclaim, and integrate his fragmented parts. Integration helps a person make the transition from dependency to self-sufficiency; from authoritarian outer support to authentic inner support. The second section describes two psychological approaches______.
Passage Two Supporters of the biotech industry have accused an American scientist of misconduct after she testified to the New Zealand government that a genetically modified(GM) bacterium could cause serious damage if released. The New Zealand Life Sciences Network, an association of pro-GM scientists and organizations, says the view expressed by Elaine Ingham, a soil biologist at Oregon State University in Corvallis, was exaggerated and irresponsible. It has asked her university to discipline her. But Ingham stands by her comments and says the complaints are an attempt to silence her. "They’re trying to cause trouble with my university and get me fired," Ingham told New Scientist. The controversy began on 1 February, when Ingham testified before New Zealand’s Royal Commission on Genetic Modification, which will determine how to regulate GM organisms. Ingham claimed that a GM version of a common soil bacterium could spread and destroy plants if released into the wild. Other researchers had previously modified the bacterium to produce alcohol from organic waste. But Ingham says that when she put it in soil with wheat plants, all of the plants died within a week.. "We would lose terrestrial(陆生的)plants... this is an organism that is potentially deadly to the continued survival of human beings," she told the commission. She added that the U. S. Environmental Protection Agency (EPA) canceled its approval for field tests using the organism once she had told them about her research in 1999. But last week the New Zealand Life Sciences Network accused Ingham of "presenting inaccurate, careless and exaggerated information" and "generating speculative doomsday scenarios (世界末日的局面)that are not scientifically supportable". They say that her study doesn’t even show that the bacteria would survive in the wild, much less kill massive numbers of plants. What’s more, the network says that contrary to Ingham’s claims, the EPA. was never asked to consider the organism for field trials. The EPA has not commented on the dispute. But an e-mail to the network from Janet Anderson, director of the EPA’s bio pesticides (生物杀虫剂)division, says "there is no record of a review and/or clearance to field test". Ingham says EPA officials had told her that the organism was approved for field tests, but says she has few details. It’s also not clear whether the organism, first engineered by a German institute for biotechnology, is still in use. Whether Ingham is right or wrong, her supporters say opponents are trying unfairly to silence her. "I think her concerns should be taken seriously. She shouldn’t be harassed in this way," says Ann Clarke, a plant biologist at the University of Guelph in Canada who also testified before the commission. "It’s an attempt to silence the opposition." Ingham insists that her testimony is based on ______.
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