A shark that walks in water instead of swimming might sound like a creature straight out of science fiction. However, that is precisely how the fish -- found in the waters of Northern Australia moves across the seafloor .The unique ocean animals were discovered by a team of scientists led by Dr. Christine Dudgeon from Australia's University of Queensland during a 12 year global conservation study.
The newly-found sharks have evolved (进化) to survive in low oxygen environments, enabling them to hunt during low tides. The researchers believe their ability to use their fins (鳍) to walk affords the sharks a remarkable edge over the smaller animals they try to bunt. “While they are super hunters in their shallow habitat, the tiny sharks present no threat to people," says Dudgeon.“At less than a meter long on average, they're incredibly cute little animals that do not look like sharks at all," she adds.
A DNA analysis of skin samples from the live fish suggests that walking sharks broke away from their original population and became a distinct species about nine million years ago. Though that may appear to be a long time ago, it is relatively recent given that sharks have been around for more than 400 million years. In fact, Dudgeon and her team believe walking sharks are the youngest kind of sharks on Earth!
The researchers say that the sharks' small numbers and small habitat make them extremely vulnerable (易受伤害) to natural disasters and overfishing. They are currently on the Nature Red List, which lists species at risk. Dudgeon and her team believe sensible conservation management plans are urgently needed to protect the walking sharks and other endangered animals from further threats.
1. What is the most noticeable feature of the newly-found sharks?A.They are cute and harmless to humans. |
B.They can survive in their shallow habitat. |
C.They walk on their fins across the seafloor. |
D.They are the youngest kind of sharks on Earth. |
A.The evolution of the shark. | B.The behavior of the sharks. |
C.The population of the sharks. | D.The DNA samples of the sharks. |
A.Adjusting the methods of fishing. |
B.Putting the sharks on the Nature Red List |
C.Changing the sharks' living environments. |
D.Adopting necessary measures to protect the sharks. |
A.Environment. | B.Nature. |
C.Education. | D.Geography. |
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【推荐1】A rhino lazily chews on some grass at her feet. A short distance away, her baby plays in a muddy pool of water. Suddenly, the mother twitches (颤动) her ears, picking up the sounds of possible danger coming near.
It’s not a lion or other wild animals that’s a rhino’s biggest threat. It’s people.
One hundred years ago, 500,000 rhinos wandered around parts of Africa and Asia. But today, rhinos are threatened with extinction. If nothing is done to save them, they could vanish forever.
Poachers (偷猎者) are killing rhinos for their horns. They do it to make money.
In some countries, people pay high prices for rhino horn. They believe that eating ground-up rhino horn will make them healthy. But that isn’t true. Rhino horn is made of keratin (角质). That’s the same thing your fingernails are made of. Eating it cannot make anyone healthy.
Humane Society International is working to help save rhinos. They wrote a children’s book and produced a video to help spread the word. The book, I’m a Little Rhino, was given to 1.5 million children in Vietnam. That country buys and uses the most rhino horn.
“The goal is to educate children about rhinos in general, and introduce the threat that poaching causes to their survival,” says Adam Peyman, program manager for HSI’s wildlife department. “It also explains that rhino horn is not effective as medicine and encourages them and their families to avoid buying or using rhino horn.”
Carter and Olivia Ries have been working to save rhinos for several years. “We made two trips to South Africa where we visited a dozen schools and met with government officials,” says Carter.“We gave the officials over 10,000 letters we collected from the youth around the world to show that the youth of the world care for rhinos. The next step was to bring that same message to the youth of Vietnam.”
Carter and Olivia visited schools in Vietnam. They want kids to bring the message back to their parents that using rhino horn “is causing the species to be pushed to the edge of extinction.”
1. What does the underlined word “vanish” in Paragraph 3 mean?A.Escape. | B.Starve. |
C.Disappear. | D.Expand. |
A.To seek pleasure. |
B.For health benefits. |
C.For personal collections. |
D.To produce artificial nails. |
A.By introducing some tough new laws. |
B.By spreading knowledge about rhinos. |
C.By sending workers to guard against poaching. |
D.By explaining the importance of protecting the environment. |
A.To collect letters from young students. |
B.To collect materials for their new book. |
C.To raise money for rhino saving programs. |
D.To arouse people’s awareness of protecting rhinos. |
【推荐2】Green Is Good
Planting and growing things offers a lot more than fresh vegetables and flowers. Working in a nice outdoor space can help you stay refreshed, promote your creativity and enrich your leisure activities.
Providing a fun workout
It’s wonderful to get out in the garden on a beautiful day to give it a tidy. Planting seeds, pulling up weeds, moving pots, pushing a lawnmower, and other gardening tasks actually provide a whole-body, moderate-intensity workout for people, especially for adults.
Having dirt under your fingernails may be a sign of poor hygiene. but scientists say it could also be a mark of good health. Thanks to beneficial bacteria found in soil, gardening may boost your immune system, helping you get sick less and fight off infections easier.
Nourishing your spirit
Increasing coordination and strength
Hand and finger strength, flexibility and coordination are essential for everyday tasks like opening jars, carrying packages and picking up children.
A.Sharpening your mind |
B.And that’s just for starters |
C.Improving your immune system |
D.Even better, whatever your age, it is a beneficial activity |
E.Working with plants provides stress relief and positive sensory stimulation |
F.The benefits come from a combination of physical exercise and the stress reduction |
G.Gardening is a great way to improve and maintain those fine motor skills and muscles |
【推荐3】Tens of thousands of nature lovers see black bears and grizzly bears each year
If a bear is coming towards you, you must first determine if the bear attack is defensive(such as when protecting young bears)or predatory(捕食性的)(such as when hunting).
Black bears do not often challenge humans, but when they do, their attacks are usually predatory. Bears do not feel threatened when they are hunting, so playing dead will not help you stay safe. During a predatory bear attack, the first thing you should do is drop any food you have and back away. If the bear still comes towards you, make as much noise as possible by shouting and hitting objects.
A.It is a good idea to collect some facts about bears. |
B.Your frightening behaviour can make the bear back down. |
C.Most walk away with exciting memories and photographs. |
D.That turns out to be a hint in some situations but not in others. |
E.Black bears and grizzly bears are likely to attack for different reasons. |
F.You should learn some life-saving skills before going on a hike in the wild. |
G.There are many ideas about how a person should react when faced with bears. |
【推荐1】BEIJING — The Chinese economy has shown positive signs of stabilizing (稳定), but it’s hard to judge what it will be next year, governor of China’s central bank said on Thursday.
Zhou Xiaochuan, governor of the People’s Bank of China, made the remarks on a panel discussion with delegates from the financial field to the 18th National Congress of the Communist Party of China, which opened here on Thursday morning.
China’s economic momentum (推进力) will depend on not only domestic conditions, but also changes brought by the global financial crisis, said Zhou, who is also a CPC delegate to the national congress.
“It has become increasingly clear that the Chinese economy is now moving towards a better direction,” he said.
Due to the impact of the debt crisis in Europe, China’s economy began slowing this year. The Chinese economy expanded only 7. 4 percent year-on-year in the third quarter of 2012, marking a downturn for seven straight quarters, the National Bureau of Statistics of China said.
As the government adopted a series of fiscal (财政的) and monetary measures and speeded up the approvals of investment projects to spur the slowing economy, the domestic economy has stabilized since September with better indicators, Zhou said.
He said it’s hard to judge how the global financial crisis will continue to affect the Chinese economy because the spreading of the European debt crisis and the so-called fiscal cliff problem in the United States have increased uncertainties of the world economy.
“We need to monitor the effect on our economy of the monetary, easing policies launched recently by the United States and the European Union,” he said.
China is likely to maintain the policy continuity to some extent in 2013, but will leave enough room to make the policy targeted and flexible.
1. What is the attitude of Zhou Xiaochuan towards the Chinese economy at present?A.Doubtful. | B.Negative. | C.Optimistic. | D.Unknown. |
A.cause | B.expand | C.decrease. | D.encourage. |
A.Global financial crisis. |
B.The debt crisis in Europe. |
C.Fiscal cliff problem in the US. |
D.The Chinese economy policy. |
A.The People’s Bank of China published the economic statistics of China. |
B.The Chinese economy policy will have a chance of flexibility in 2013. |
C.The world economy is uncertain. |
D.The global financial crisis has a great effect on the Chinese economy. |
【推荐2】A reentry capsule(太空舱)carrying the crew —— Chen Dong, Liu Yang and Cai Xuzhe —— touched down on Earth at the Dongfeng Landing Site in northwestern China’s Gobi Desert after flying nine hours. This has become the first time that Chinese astronauts have returned to Earth at night, which meant low temperatures and low visibility. Many technologies were developed to make sure the Shenzhou - 14 crewed spaceship went back safely.
The temperatures can be tricky. From the moment the spaceship separated from the space station on the way home, it has to start its own thermal (热 的) control system to keep the temperature between 17 and 25 degrees, an ideal condition for the astronauts. When the spaceship enters Earth’ atmosphere, it can cause temperatures of over 1, 000 degree Celsius, so the ship has a heat shield on its bottom to protect itself from the high temperature.
High efficient communication is another promise of the safe return. The ground teams including control center in Beijing, landing site and rescue teams use the BeiDou Navigation Satellite System. The rescue helicopters also have a smart system to help predict the path of the reentry capsule during landing.
When the spaceship is 10 kilometers above the ground, the three parachutes (降落伞) will open one after another. The size of the parachutes will expand from only several square meters to over 1, 000 square meters, gradually reducing the spaceship speed from 200 meters per second to seven meters per second, which protects astronauts from gravity force overload. “It’s like when we’re driving, we need to slow down gradually, ”said Rong Wei, chief designer of manned spaceship at the 5th Academy of Aerospace Science and Technology Group, At the same time, the engine will be ready for a soft landing.
1. Why was Shenzhou- 14 spaceship’s returning different than before?A.Because the landing site is in the Desert. |
B.Because there are less astronauts in Shenzhou- 14. |
C.Because the returning time was put off. |
D.Because it was cold and dark outside. |
A.It was controlled to fit astronauts’ condition. |
B.It was the highest at the very beginning. |
C.It went to the frozen point in the atmosphere. |
D.It kept dropping before starting the control system. |
A.To design the best landing spot. | B.To assure the location of the capsule. |
C.To control the temperature in capsule. | D.To send orders from the capsule. |
A.How the engine expanded parachutes. | B.How the gravity force influenced landing. |
C.How the landing parachutes worked. | D.How astronauts controlled the landing. |
【推荐3】During the Beijing 2022 Winter Olympics, foreign journalists not only enjoyed the Chinese athletes’ excellent performance, but experienced “the speed of China” in the development of high-speed rail.
On Feb. 14, 57 journalists from 36 Chinese and foreign media groups were invited by the 2022 Beijing Media Center to visit the city’s rail transit command center to explore the “secret” of Beijing’s high-quality development in the field.
Beijing has formed a safe, convenient, efficient and green rail transit system. It now consists of 27 metro lines, increased from two in 2001 when Beijing won the bid to host the 2008 Olympic Games. Last year, the city’s metro lines together handled nearly 10 million passenger trips per working day, accounting for 57 percent of the total number carried by urban public vehicles.
Compared with car travel, each subway passenger can reduce 77 percent of their carbon emissions, which means the total reduced carbon emissions can reach 7. 38 million metric tons a year. This is equal to the amount of carbon dioxide absorbed by 410 million trees, experts said. In addition to efficiency and ecological protection, the city’s urban rail transit is becoming more intelligent. For example, the west part of Metro Line 11 is known as a line serving the 2022 Winter Olympics, which features a fully automated driving mode under staff supervision at the beginning of the train’s operation.
Although China was behind developed countries in high-speed railway development, it has accumulated abundant experience in constructing all types of railways, including high-speed and railways at high altitudes and carrying heavy loads. The country also has the longest high-speed rail mileage, which accounts for more than 66 percent of the world’s total.
“China’s high-speed trains run across rivers and mountains to reach all directions, from forests and snowy fields in the north to wetlands south of the Yangtze River, and from the desert in the west to the East China Sea,” said Zou Wu, a senior engineer at the China State Railway Group. “The country’s high-speed railway network covers 92 percent of the cities each with a population of more than 500, 000 people.”
1. Why did journalists visit Beijing’s rail transit command center?A.To enjoy the Chinese athletes’ excellent performance. |
B.To visit Beijing Media Center with some foreign tourists. |
C.To figure out Beijing’s rapid development of high-speed rail. |
D.To explore the “secret” of the cultural development of Beijing. |
A.Car travel’s carbon emissions are reduced by 77 percent. |
B.The total carbon emissions are increased because of the railways. |
C.Passengers completely control their carbon emissions by subway. |
D.Taking a subway will be beneficial to the environment of the city. |
A.China’s high-speed trains reach everywhere. |
B.China’s high-speed trains are applied widely. |
C.China’s high-speed trains promote the forests’ growth. |
D.China’s high-speed trains run from the desert in the east. |
A.High-speed railway depresses Olympics’ journalists. |
B.High-speed railway impresses Olympics’ journalists. |
C.High-speed railway improves Olympics’ quality efficiently. |
D.High-speed railway influences Olympics’ athletes’ careers. |