The fruit-tree pinhole borer (针孔蛀虫), as its name implies, makes holes in fruit trees. It lays its eggs and raises its young in the galleries thus created . Yet the beetles (甲虫) do not feed directly on the wood they bore into. Instead, they devour fungi (真菌) that grow on the wood thus exposed.
Researchers have long suspected that this is a form of farming, because they have evidence that the beetles carry spores (孢子) of their preferred crop, R. sulphurea, into their smallholdings—in effect, sowing it there.
Observations of natural fruit-tree pinhole-bore r dwellings suggest that R. sulphurea grows in them more abundantly (大量地) than might be expected, given all the fungal competition around—but not why. To check whether the beetles are, indeed, weeding their crop, Janina Diehl and Peter Biedermann of the University of Freiburg did an experiment.
In the laboratory, they had mother beetles of the little wood bore restablish nests, in which the typical fungal gardens formed. But before the beetles had started laying their eggs, they collected all of the beetles and then returned half to their dwellings while leaving the other nests empty. Genetic analysis of the fungal gardens after 40 days showed that the presence of the beetles had greatly changed the fungal community. Twenty days after that, they sampled the gallery walls for fungi.
As they had hoped and expected, R. sulphurea was much more abundant in beetle-tended galleries than in those without residents. In the former, it made up half of the fungal mass extracted. In the latter, less than a third. These beetles are indeed weeding their crop.
“Further research into how exactly the beetles suppress the growth of weed fungi could alsoprovide worthwhile insights for human agriculture, which is struggling with weed resistance, for example,” says Biedermann. “It’s highly exciting for us to see how nature has been doing this for 60 million years. We humans can still learn something from these mechanisms.”
1. What does the underlined word “devour” in paragraph 1 mean?| A．Sow. | B．Tend. | C．Eat. | D．Move. |
| A．The number of the mother beetles. | B．The presence of the beetles. |
| C．The quality of food fungi. | D．The types of weed fungi. |
| A．They weed crops. | B．They feed on fruit. |
| C．They live in groups. | D．They lay eggs in trees. |
| A．The research findings are of little value. |
| B．Measures should be taken to protect the beetles. |
| C．Fungi cause much damage to human agriculture. |
| D．Further research to the beetles might benefit farmers. |
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The dog's name is Trouble. And apparendy Trouble is still alive. Of course, I would hang on,too, if someone left me $12 million. Look! Top-shelf dog food, soft pillows everywhere, drivers walking me in nice leafy parks. I would live to be 110 in dog years.
The dog's story is still fresh in my mind the other night when I leave a steak house after a superb meal. Then I notice a woman carrying a small bag out of the door behind me.
Once outside, she walks over to where a man is holding a tiny dog hke it's a baby. The dog looks like a Maltese, too, barking and annoying, with a cute haircut,
And now I am treated to an absolute astonishing sight. Because now the woman reaches into the bag and begins pulling out little pieces of meat, which she puts on a plastic spoon and feeds to the dog.
This is no cheap steak house. It's actually, way out of my league --I'm there only because it's a special occasion. I can tell you this: if I walked out of the place with any leftover steak, it sure wouldn't go to a dog. Not at those prices.
So now the woman is Spoon-feeding the dog and the man is just standing there, holding this dog and looking as if this is the most normal thing in the world. And the dog is calmly chewing these pieces of steak as if he's a little king. And this dog is in no hurry. He's having a great time.
A few minutes go by, and now the dog finishes all of his steak. At this point, I hear the woman say to the man "Think he's still hungry?" And she glances behind her at the restaurant, as if she might go back in there to get more steak for the dog.
Watching all this, I'm afraid I'm going to shout, "Are you out of your mind? Feeding all that pricey steak to that little dog? Did you see what our American life is like today? We're all going to be eating dog food if this keeps up!"
1. Why would the author live to be 110 in dog years?
| A．Because he is always in poor health and falls ill. |
| B．Because a Maltese dog lives longer than a human being. |
| C．Because his grandparents left him a large sum of money. |
| D．Because he thinks the dog is treated extremely well. |
| A．An American family's happy life. |
| B．A Maltese dog getting $12 million from its owner. |
| C．A New Yorker spending $ 8 billion for a few banks. |
| D．A pet dog being fed with expensive food. |
| A．the restaurant is too expensive for the author |
| B．the author hates the dog being taken there |
| C．the superb restaurant is about to be out of service |
| D．the dog doesn't belong to the author's group |
| A．indifferent | B．annoyed | C．concerned | D．envious |
【推荐2】Despite the bad reputation of sharks, they are crucial to the health of the marine ecosystem and can even help fight climate change.
In the shallows of Shark Bay, Western Australia, seagrass is food for the sea cows, which can weigh as much as 500 kg and eat roughly 40 kg of seagrass a day. Sea cows are a rich source of food for tiger sharks. By keeping the sea cow population controlled, tiger sharks here help the seagrass grow sustainably. A booming seagrass meadow stores twice as much CO2 per square mile as forests typically do on land.
But tiger shark numbers are declining. Off Australia’s northeast coast of Queensland, tiger sharks are estimated to have fallen by at least 71 percent, largely due to overfishing. A reduction in tiger sharks means more seagrass consumed by herbivores (食草动物) and less carbon stored in sea vegetation. This raised the question: What if they were absent from the Shark Bay — would the seagrass-dominated ecosystem survive?
To find out, researchers led by Rob Nowicki of Florida International University, spent time in Eastern Australia, where shark numbers were lower and sea cows ate seagrass largely undisturbed. “When uncontrolled, sea cows can rapidly destroy wide areas of seagrass.” said Nowicki.
Those findings emphasized that tiger sharks were playing an important role in preventing the reduction of seagrass in Shark Bay. If their populations continue to decline, the resilience of carbon-rich ocean ecosystems will likely decrease.
When it comes to stimulating shark numbers, there have been movements toward more sustainable fishing, but a large percentage of the industry have not changed their methods, which is a reason why the population of many marine top predators (捕食者) continues to decline.
Aside from supporting sustainable fishing, Nowicki said the only way to truly protect marine life is to reduce our global greenhouse gas emissions. “Ultimately, if we are going to protect our ecosystems in the centuries to come, we are going to need to solve climate change while undertaking species protection at the same time.”
1. Why are tiger sharks vital to the marine ecosystem?| A．They feed on various sea animals. |
| B．They can store large amounts of CO2. |
| C．They can prevent the loss of seagrass. |
| D．They influence marine species’ distribution. |
| A．Sustainability. | B．Recovery. | C．Preservation. | D．Construction. |
| A．Climate change. | B．Lack of protection. |
| C．Unsustainable fishing. | D．Loss of seagrass. |
| A．The number of tiger sharks is decreasing. |
| B．Climate change causes the loss of seagrass. |
| C．Environmental protection is at the top of the agenda. |
| D．Tiger sharks are vital to the health of the marine ecosystem. |
【推荐3】There are about 5,000 different kinds of ladybugs in the world. They are also known as lady beetles or ladybird beetles. They come in many different colors and patterns, but the bestknown in North America is the sevenspotted ladybug, with its shiny, redandblack body.
In many cultures, ladybugs are thought to be good luck. Most people like them because they are pretty, lovely and do no harm to human beings. But farmers love them because they eat aphids and other planteating pests. One ladybug can eat up 5,000 insects in its lifetime!
Most ladybugs have domeshaped bodies with six short legs. Depending on the kind, they can have spots, stripes, or nothing at all. Sevenspotted ladybugs are red or orange with three spots on each side and one in the middle. They have a black head. Ladybugs are colorful for a reason. They tell the enemy: “Eat something else! I taste terrible.” When threatened, they may play dead. Birds are ladybugs' main predators, but they are also eaten by frogs, spiders, and dragonflies.
Ladybugs are happy in many different places, including grasslands, forests, cities, suburbs, and along rivers. Sevenspotted ladybugs are native to Europe but were brought to North America in the mid1900s.
Ladybugs are most active from spring until fall. When the weather turns cold, they look for a warm place to hibernate, such as in rotting logs, under rocks, or even inside houses. These hibernating places can have thousands of ladybugs.
The name “ladybug” was given by European farmers who prayed to the Virgin Mary when pests began eating their crops. After ladybugs came and wiped out the invading insects, the farmers named them “beetle of Our Lady”. This later was shortened to “lady beetle” and “ladybug”.
1. The underlined word “aphid” in Paragraph 2 is probably a kind of .| A．pest | B．bird | C．plant | D．tree |
| A．all ladybugs have spots | B．the colorful body can protect them |
| C．most ladybugs are red or orange | D．frogs are not one of the predators |
| A．Ladybugs can live along rivers. |
| B．Sevenspotted ladybugs were brought to Europe from North America. |
| C．Ladybugs are very active in autumn. |
| D．The name “ladybug” came from “beetle of Our Lady”. |
| A．Sevenspotted Ladybugs | B．The Development of Ladybugs |
| C．The History of Ladybugs | D．Ladybugs |
【推荐1】In his famous painting, Impression, Sunrise, Claude Monet keeps the details to a bare minimum. A light mist provides a foggy background to the sunrise in the French seaport of Le Havre while boats are just suggested by a few rough brushstrokes in the foreground, where orange and yellow colors contrast sharply with the dark boats and water. The whole picture seems like an unfinished work.
Actually, Monet himself saw the work as unfinished since he just had enough time to catch a rough impression of the moment. And it was for that reason that he adopted the title “Impression” to distinguish it from his other works about Le Havre.
From the April 15 to May 15, 1874, Monet exhibited this work with those of Camille Pissarro, Alfred Sisley, Edouard Manet, Paul Cézanne, Edgar Degas, and some other thirty artists. They organized the exhibition on their own as they were rejected at the Paris Salon.
Monet’s Impression, Sunrise enjoyed the most attention and visitors even claimed that they were absolutely unable to recognize what was shown at all. A critic, Louis Leroy, who attended the exhibition, wrote a now-famous article in Le Charivari in which he used the term “Impressionist” based on the title of this painting. Despite the fact that Leroy had used the word in a negative sense, the group decided to adopt it and the painters were happy to be called Impressionists. Today, Impression, Sunrise is considered as one of the best-known paintings.
Although the painting is very famous, it is in many ways untypical of Monet’s own work of this period and of Impressionism. It shows little of the Impressionist treatment of light and colour and the painting is strongly emotional rather than analytical.
Nevertheless, the highly abstract technique employed to catch a rough impression of the moment does illustrate particularly well the revolutionary (革命性的) feature of an Impressionist painting. At that time, this technique was still completely alien to viewers.
1. Which statement can best describe Impression, Sunrise?| A．It is a typical Impressionist work. | B．It is analytical rather than emotional. |
| C．It appears very rough and unfinished. | D．It is best-known for the treatment of colors. |
| A．Cautious. | B．Disapproving. | C．Favorable. | D．Tolerant. |
| A．New. | B．Appealing. | C．Understandable. | D．Affordable. |
| A．Features of Impressionism | B．Selected Works of Impressionists |
| C．Representatives of Impressionism | D．Impression, Sunrise by Claude Monet |
【推荐2】Can exercise during childhood protect you against memory loss many decades later? Exercise early in life seems to have lifelong benefits for the brain, in rats at least.
“This is an animal study, but it shows that physical activity at a young age is very important—not just for physical development, but for the whole lifelong track of cognitive（认知的）development during ageing,”says Martin Wojtowicz of the University of Toronto, Canada.“ In humans, it may delay the appearance of Alzheimer's symptoms（阿茨海默氏症）, possibly to the point of preventing them.”
Wojtowicz’s team divided 80 young male rats into two equal groups, and placed running wheels in the cages of one group for a period of six weeks. Around four months later—when the rats had reached middle age—the team taught all the rats to connect an electric shock with being in a specific. When placed in the box, they froze with fear.
Two weeks later, the team tested the rats in three situations: exactly the same box in the same room, the same box with the room arranged differently, and a completely different box in a different room.
The rats without access to a running wheel when they were young now froze the same percentage of times in each of these situations, suggesting they couldn't remember which one was dangerous. But those that had been able to run in their youth froze 40 to 50 percent less in both changed box settings.
"The results suggest the amount of physical activity when we're young, at least for rats, has influence on brain and cognitive health—in the form of better memories—when we're older," says Arthur Kramer of Northeastern University in Boston, who has found that, in humans, exercise promotes the growth of new brain cells.
1. The study shows that_____.| A．physical activity is important for physical health |
| B．using the running wheels is of benefit to the rats’ growth |
| C．physical activity can prevent human’s Alzheimer's symptoms |
| D．the more exercise a rat has when young, the better memory it will possess when older |
| A．By analyzing causes. |
| B．By giving an example. |
| C．By describing the process. |
| D．By showing differences. |
| A．Exercise. | B．Development. |
| C．Benefit. | D．Study. |
| A．Negative. | B．Objective. |
| C．Critical. | D．Doubtful. |
【推荐3】If you want to get the most out of the study of a language, you must also read for pleasure:（乐趣） novels, plays, travel books, and so on．And in reading books of this kind the important thing is to get on with the reading; to try to grasp (抓住)what the writer is going to tell you in the book as a whole．This is impossible if you stop and think over the meaning of every single word which happens to be unfamiliar(不熟悉)．You can not enjoy a story if you stop half a dozen times on every page in order to look up words in the dictionary．You may even prevent yourself from understanding the story as a whole by doing this．
When you are reading books of this kind, therefore, you will usually have to rely mainly on(依靠) the context (上下文) to help you．If you meet an unfamiliar word, do not let it take too much of your attention from the main thread(主线) of the story．In all probability(可能) you will meet the same word again a few pages later on in a slightly(细微的) different context, and each time you see it that your understanding of it will become more exact．
1. When you meet new words in reading such kinds of books, you’d better _______.| A．stop and look them up in a dictionary | B．stop and think them over |
| C．try to guess their meanings from the context | D．have none of them |
| A．to read very slowly | B．to read quickly and not too carefully |
| C．to read very carefully | D．to read very seriously(严肃地) |
| A．Read for Pleasure | B．Get on with the Books |
| C．Reading Skills | D．The Importance of Reading |
