Scientists have been able to track the entire life of a mammoth (猛犸象) that lived more than 17,000 years ago. The team figured out where in Alaska it likely was at any given point of its 28-year life.
To do so, the researchers closely studied a 1.8-meter-long mammoth tusk (象牙) dating back around 17,100 years. Mammoth tusks grow by adding layers of tissue almost daily, forming rings like a tree that can reveal detailed information.
The main thing the researchers analyzed was strontium isotopes (锶同位素), which can act almost like an ancient GPS. Different areas have different isotopic features, which start in minerals deep underground and make their way to the top of the land, into plants and water. Finally, they can be seen on the animals that consume those plants and water.
Previous studies had produced an isotopic map of Alaska by analyzing isotopes in the teeth of hundreds of small animals, which don’t travel far in their lifetimes and so represent a local area. The researchers can then compare isotopic signals from each part of the mammoth’s tusk to this map, to get an idea of where the mammoth most likely wandered throughout its life.
The scientists started from where its remains were found. Working backwards, the scientists then looked at the isotopic feature of where the mammoth was about a week before death, then searched the map for the best match in a nearby area. A model then worked backwards stepwise to determine the most likely routes the mammoth might have taken.
According to the research, the mammoth seems to have spent his early years in the Yukon River Basin and Alaska, constantly trekking between several territories in a predictable pattern. The team says that this behavior seems to be like modern elephants, moving regularly from place to place.
1. What is the key to reading the mammoth’s tusk?| A．The length of the tusk. | B．The age of the mammoth. |
| C．The area the mammoth lived in. | D．The tissue found in the tusk’s layers. |
| A．Plants and water are main carriers of isotopes. |
| B．The isotopes in the tusk came from the underground. |
| C．It was difficult to analyze the isotopic features of an area. |
| D．The researchers were surprised to find isotopes in the tusk. |
| A．By explaining the significance of tusks. | B．By recording the animal species of Alaska. |
| C．By offering researchers a map to compare with. | D．By proving the possibility of analyzing isotopes. |
| A．Looking for food. | B．Escaping from dangers. |
| C．Making a long journey. | D．Sending warning signals. |
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【推荐1】Migratory (迁徙的) birds flying to China’s largest freshwater lake for winter are likely to face a tougher environment than before. Little rainfall, a record drought, and the earliest dry season in the Poyang Lake area — all exacerbated by climate change — have threatened the food supply and habitat of wintering birds, domestic media reported Monday.
Known as a “migratory bird haven,” Poyang Lake and its surrounding wetlands and ponds serve as one of the most important wintering stopovers for hundreds of thousands of migratory birds, including Siberian cranes and oriental white storks. The lake’s seasonal shrinkage provides abundant food to the waterbirds and helps maintain their habitat.
Duan Qingxian, director of the nonprofit Poyang Lake Wildlife Rescue Association, said on Tuesday that migratory birds inhabiting the lake area, as monitored by his team, had declined by at least 50% compared with the same period over the past years. “There is less food such as grassroots, snails, and shells for waterfowl (水禽) due to the drought,” said Duan, who has lived in Duchang on the north side of the lake for over 40 years. “While patrolling the lakeside this year, I saw several dozen geese at a time flying from north to south, instead of hundreds previously.”
In September, local authorities started drawing water from Poyang Lake’s main channel to replenish nearby sub-lakes. They also cut grasses that were too old and hard for the birds to eat to make the grass sprout (抽芽). Duan said that human efforts to minimize the effects of changing weather patterns were just “a drop in the bucket” for a massive lake like Poyang. “We just do what we can do to reduce the impact of the drought on migratory birds as much as possible,” Duan said. “As long as the weather cools, and it rains, the tender grass will grow, and more birds will come.”
1. What does the underlined word “exacerbated” in Paragraph 1 mean?| A．Worsened. | B．Improved. | C．Replaced. | D．Eased. |
| A．To define a concept. | B．To give some examples. |
| C．To present a new argument. | D．To add background information. |
| A．Measures adopted to save the migratory birds. |
| B．Difficulties in monitoring the birds in the lake. |
| C．Terrible situation caused by the severe drought. |
| D．Suitable food for the wintering birds in the lake. |
| A．About 50% the waterbirds living on the lake will starve to death. |
| B．Current measures to stop the lake from drying are very effective. |
| C．It’s necessary to offer some artificial food for the migratory birds. |
| D．The drought’s impact may be relieved when the temperature falls. |
【推荐2】A five-year-old dog named Millie is helping to keep the streets of Hereford, England, clean with her 80-year-old owner Alfie Kitson. Kitson only has to point at a bit of rubbish on the floor and say, “Put that in the bin,” and Millie will do what he bids.
Millie was just eight months old when she was found abandoned in a rubbish bag tied to a tree branch in Spain, where Kitson and his family lived for 20 years. After giving her a new home, Kitson later spotted a soldier and his dog doing the trick in a park and set about trying to get Millie to do the same.
He began putting a box, of similar size to a public bin, in their Spanish garden, and bit by bit, he raised its height as she understood to drop things in the box. And luckily, the bins in Hereford were just the right size for Millie to showcase her talent when she moved to Britain with Kitson and his wife.
“Obviously, environmental concerns are a hot topic at the moment, so if we can help clear up rubbish and plastic off the street, then we’re doing our bit to help,” Kitson said. “We rescued her because our house felt empty without an animal. Dogs and cats are a big part of the life of anyone who loves animals. She is the family, and we are glad we can show her off to neighbors as she is really an amazing dog.”
Hereford office worker Samuel Tiler regularly spots Millie working her magic in the city center.
“The first time I saw her do it, I thought I might be going mad. I thought, ‘Is that really a dog tidying up people’s litter?’” he said of the dog. “I just wish people could be more thoughtful as it shouldn’t take a dog to clear up after them,” Tiler added. “If you’ve got a dog taking responsibility for the environment — surely we can do the same.”
1. What does the underlined word “bids” in paragraph 1 probably mean?| A．Commands. | B．Promises. | C．Misses. | D．Witnesses. |
| A．Before he bought his new home in Spain. | B．When Millie was less than eight months old. |
| C．After he saw a man training his dog. | D．After he moved to his new home in Britain. |
| A．To show off to his neighbors. | B．To guard his house. |
| C．To accompany him and his wife. | D．To clean up the rubbish in the park. |
| A．Dogs are really friendly to humans. |
| B．Humans have to pay the price for their mistakes. |
| C．More dogs should be trained to help keep the environment tidy. |
| D．Humans should do their part in keeping the environment clean. |
【推荐3】Some years ago, Michel-Andre found himself staring at the body of a dead whale on a beach in the Canary Islands. It was obvious that the animal had been struck violently by a ship——but why? Only later, after surveying the whales which lived in the area and measuring the increase of sound pollution from ships did it become clear that there was a link.
The whales had become desensitised to the noise of approaching boats and were being struck by them, often seriously. “We never thought that this could be something that could kill,” recalls (回忆) Andre, who is the director of the Laboratory of Applied Bioacoustics at the Technical University of Catalonia, Barcelona.
Andre has spent 20 years developing an advanced system to better understand why incidents like this happen. His underwater microphones have exposed a world of deafening sound and animal communication never observed with such clarity(清晰) before.
It was not an easy task. Sound waves don't travel through water in the uniform, predictable way they do through the air. Instead, the temperature, salinity (盐度) and, flow of water have great effects on their path.
What can be done? One solution is to change shipping routes to courses where ships are statistically less likely to meet animals. It’s also possible to slow ships down to 18km/h or less, which is less likely to seriously injure a whale.
As for dealing with the root cause of the problem, the UN’s International Maritime Organisation has already published guidelines on how to quieten ships, but it will be a while before the effects of such changes might be observed.
“The ocean is not our world,” comments Andre. But it is ours to look after. And thanks to his work, we can better understand the effects of subsea sound pollution.
1. What does the underlined word “desensitised” in Paragraph 2 mean?| A．Stubborn. | B．Flexible. | C．Dull. | D．Friendly. |
| A．To lower the speed of ships. |
| B．To reduce the number of ships. |
| C．To set up preserves under the sea. |
| D．To give the injured animals timely treatment. |
| A．Doubtful. | B．Disapproving. | C．Positive. | D．Uncaring. |
| A．A great expert. | B．Noise in the sea. |
| C．Animals in the sea. | D．Sea exploration technology. |
【推荐1】That the Leaning Tower of Pisa no longer leans quite so much after a￡20 million project to save it has proved to be a great success. The tower, which was on the edge of collapse, has been straightened by 18 inches, returning to its 1838 position.
“It has straightened a little bit more than we expected, but very little helps,” said Prof. John Burland, the only British member of the rescue committee. “The tower is still very slightly moving towards being upright.”
The tower, which has been leaning almost since building work first began in 1173, was closed to the public in 1990 because of safety fears. The 183-foot tower was nearly 15 feet off vertical and its structure was found to have been weakened by centuries of strain (作用力).
Prof. Burland said it could have collapsed “at any moment”. However, it took nine years of quarreling before any work was done. The last attempt at straightening the tower was carried out. Concrete was poured into the foundations, but the result was that the tower sank further into the soil.
The straightening work involved digging out around 70 tonnes of earth from the northern side of the tower, causing it to sink on that side. Before the digging started, the tower was fixed with steel ropes and 600 tonnes of lead weights.
However, halfway through the project, concerns about the ugliness of the weights led to their removal and the tower leaned greatly. The weights were hurriedly reattached. In one night, the tower moved more than it had averaged in an entire year. The tower’s stonework has also been restored.
The Italian government stepped in after a tower collapsed in Pavia in 1989, killing four people. Experts suddenly realised that the tower at Pisa, which was similarly built and on the same sort of earth, could do the same.
1. What would be the best title for the passage?| A．The Building of the Leaning Tower of Pisa |
| B．Saving the Leaning Tower of Pisa |
| C．The Collapse of the Leaning Tower of Pisa |
| D．The History of the Leaning Tower of Pisa |
| A．closed for the straightening work in 1990 |
| B．began to lean more than 800 years ago |
| C．has a history of more than 1,000 years |
| D．has become vertical |
| A．The development of new technology. |
| B．The advice of Prof.John Burland. |
| C．The expectation of the rescue committee. |
| D．The collapse of a tower in Pavia. |
| A．The lead weights fixed to the tower. |
| B．Restoring the stonework. |
| C．Pouring concrete into the foundations. |
| D．Digging earth from the southern side of the tower. |
【推荐2】A few years ago, a company called Space Marketing came up with a plan to send a mile–long advertisement into space. To advertising agencies (机构), it would have been “a dream come true”. However, advertising standards agencies finally decided not to allow Space Marketing to go ahead with their plans and they were forced to give them up.
Space may indeed be the final place for advertisers, because on Earth we are already surrounded by advertising wherever we are and whatever we are doing. Apart from the obvious adverts that we see every day on TV, and in newspapers and magazines, there is a whole “other world” of advertising messages for our attention. There are ads that we see on the side of the bus we catch to work, for example. And what about the logos (商标) we see on the clothing of the people we walk past in the streets?
Most of the time, we are probably not even aware of (意识到的) these less obvious advertising methods, but that doesn’t mean that they don’t work. Take “product placement”, for example. You are in a cinema, watching the latest Hollywood movie. Look carefully at the make of car your favorite actor is driving. And what about his watch? Can you see what brand it is? Chances are, you can, and the company that owns the brand is likely to have paid thousands for it to appear in the film.
So, whether Space Marketing finally succeeds in sending ads into space or not is perhaps less important than it might seem. This would not change a thing. Our everyday lives are already strongly influenced by advertising whether we realize it or not.
1. What happened to the plan of sending an ad into space?| A．It came to nothing. |
| B．It was a dream come true. |
| C．It had to wait a few years before it was carried out. |
| D．It was supported by the advertising standards agencies. |
| A．By showing research findings. |
| B．By explaining research findings. |
| C．By giving instructions. |
| D．By using examples. |
| A．costs a little |
| B．doesn’t work |
| C．is less obvious than TV ads |
| D．mainly appears in Hollywood movies |
| A．We live in a world of advertising. |
| B．We’ve changed a lot because of advertising. |
| C．Space Marketing leads in the advertising industry. |
| D．Space ads will mark the beginning of a new world. |
They conducted a study that showed younger children aged 3-4 were most hungry for more stories, with over three-quarters saying they wished their parents read to them more often.
More than half of all children aged 3-8 said story time was their favourite pastime with their parents.
"The results of our research confirm the traditional activity of storytelling continues to be a powerful learning and emotional resource in children’s lives," said child psychologist Richard Woolfson.
Storytelling ranked higher than television or video games among pastimes for kids, and 82 percent said reading a story with their parents helped them sleep better, according the survey of 500 children aged 3-8 in Britain.
The best storytellers were mothers who used funny voices to illustrate different characters or made their own special sound effects to keep the story moving, researchers said.
When mum and dad are not at hand, celebrities will do: over 30 percent of children said they would like to hear a bedtime story from Harry Potter star Daniel Radcliffe, with teen idols Zac Efron, Miley Cyrus and Emma Watson.
"It can be very difficult for parents to find the time to read with their children, but these moments can help build strong bonds and play a vital part in their child’s development," said Woolfson.
1. The underlined word “pastime” in the passage mot probably means .
| A．old time | B．entertainment | C．emotion | D．character |
| A．pointing out similarities and differences | B．following the natural time order |
| C．comparing opinions from different fields | D．providing examples and statistics |
| A．grow stronger | B．become more emotional |
| C．sleep better | D．become more powerful |
