Sharks are often regarded as cruel animals, the lone wolves hiding in the deep, hunting for animals. But that is increasingly out of step with what scientists are learning about the animals. Instead, they say, some species of sharks are social creatures.
They form these social groups where they hang out with the same individuals over multiple years," says Yannis Papastamatiou from Florida International University.
Papastamatiou s team studied gray reef sharks(灰礁鲨) populating the waters off Palmyra Atoll in the central Pacific Ocean. They attached small location transmitters(位置信号传送器) to 41 sharks, which allowed them to track the animals' movements. Also, two sharks were equipped with small video cameras9 which could record a shark's-eye view of their daily lives.
After tracking the sharks for four years, the researchers found that the same groupings of sharks—ranging from a couple up to as many as 20—frequently returned to the same parts of the reef over and over again. They also found that some of the groups stuck together during the study period.
"The sharks might be inspired to stay together because it makes hunting for food easier," Papastamatiou says. "If we hang out together and I see something, then you can come and try and take advantage of that. And alternatively, if you see something, then I can try and take advantage of that."
He points out that the sharks don't cooperatively hunt, but says that as long as the group isn't too large——which would raise competition and conflict—socializing appears to benefit the sharks.
David Shiffman, who studies shark protection, says he was surprised to learn that the sharks stuck together for so long. "Sharks are smart creatures," Shiffman says. "In addition to knowing where to find food by watching others, some species of sharks can also learn to solve simple puzzles, just by watching other sharks solve them."
1. What is a misunderstanding about sharks?A.They normally hunt alone. | B.They stay away from reefs. |
C.They go hunting in groups. | D.They are powerful animals. |
A.They equipped 41 sharks with cameras. |
B.They created artificial reefs for sharks. |
C.They dived into the sea to watch sharks. |
D.They employed positioning technology. |
A.By sharing food with each other. |
B.By cooperating to solve problems. |
C.By following group members' examples. |
D.By growing stronger through competition. |
A.Sharks Are Very Lonely Animals |
B.Feel Afraid of Sharks? Calm Down |
C.Everyone Needs Friends—Even Sharks |
D.A Large or Small Group: Which Is Better? |
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【推荐1】While out hunting for ducks near Perry Lake, Kansas, Jake Atkins and his friend accidentally got trapped in sinking mud, which they unknowingly walked right into.
"We were walking pretty much side-by-side, and we both sank to knee depth in the mud and we tried to wiggle(扭动)ourselves out and it ended up being waist deep," Atkins said. They realized that if they struggled any more, they would only sink further, so Atkins called 911 and they tried to stay as still as possible until help arrived.
Atkins' dog, Otis, waited nearby but jumped to action when firefighters failed to save his owner. "If they'd walked out, they would've sunk too. So there was no way for them to get rope to us. So when those firefighters popped out of the bushes, I said just tie the rope onto Otis," Atkins said.
Otis bravely walked out onto the sinking mud three times to rescue the gear, Atkins friend, and finally Atkins. By the final trip, Otis was crying from exhaustion(精疲力竭)but refused to rest until Atkins was safe. " He followed me as they were pulling me. He kind of just was walking right beside me as they were pulling me in on my back. It was kind of funny," Atkins said.
Watch the entire video below to see what this dog did to save his owner from sinking mud.
Can you believe the fire department couldn't even save the two hunters? Let us know what you think in the comments below.
1. How did the two hunters get trapped?A.By chance while hunting. | B.On purpose while training a dog. |
C.They were pulled in by ducks. | D.Otis set the trap for them. |
A.To wait for Otis to save them. |
B.To wait for the ducks and shoot them. |
C.To avoid sinking deeper into the mud. |
D.To be able to call 911. |
A.The fire department failed to save the hunters finally. |
B.Otis saved the two hunters in one go. |
C.Otis pulled the two hunters out. |
D.The dog played the key role in the rescue. |
A.A book about dogs. | B.A website. |
C.A newspaper. | D.A magazine. |
【推荐2】An elderly couple in the UK claimed that they were held hostage by a pair of seagulls nesting on the roof of their home. Every time they tried to leave, the birds would become aggressive and attack them.
One time, when Roy Pickard, the 71-year-old husband, decided to take his chances and go outside, he was hit so hard on the back of the head that he had to be taken to the hospital for help. Local authorities have installed a gazebo outside the couple’s home, which should offer some protection. That’s the best they can do for now.
“The whole thing has been terrible,” Roy old reporters. “I’ve not been able to go out of the front door. If I try to get out of the door, the two adult birds are right there, and I’ve got no chance. It’s really frightening. My wife isn’t well at the moment, so we’re relying on me to get out.” Luckily, the Pickards’ garage is connected to their house and he can get out through there when he needs to do some shopping, but he doesn’t dare get out of the car to close the garage door, so he always leaves it open until he comes back.
Roy has complained about the situation to both the local authorities and animal organizations like the RSPCA and RSPB, but their solutions have not been very helpful. The Wyer Council says that seagulls are protected while nesting, so all they can do is try to make the couple’s life bearable by installing a gazebo and making arrangements so that the 77-year-old wife, Brenda, can reach her private appointments safely. Unfortunately, animal organizations wouldn’t help the Pickards either. For now, all they can do is wait for the chicks to fly away. “The RSPCA and RSPB have been no help whatever. They seem to put the rights of these birds above those of people , which is ridiculous,” Roy said.
1. What is the problem facing the Pickards?A.The door of their garage can’t be closed. | B.They can’t walk out because of the seagulls. |
C.Their pet birds often attack them aggressively. | D.A flock of birds nested on the roof of their house. |
A.Tell them to wait until the birds fly away. | B.Build a gazebo to provide some protection. |
C.Send people to guard them outside the home. | D.Make arrangements for them to have appointments. |
A.It wants to protect the seagulls. | B.It is looking for an ideal solution. |
C.It will help Roy do some shopping. | D.It hopes the couple can lead a simple life. |
A.The RSPCA and RSPB are useless. | B.Birds are more valuable than humans. |
C.It is ridiculous for people to help others. | D.Roy is disappointed with the authorities’ actions. |
【推荐3】The poaching, or illegal killing, of rhinos(犀牛) in South Africa is growing worse each year. The government recently reported that a record number of rhinos were poached in 2014, a year which had more rhino killings in South Africa than ever before.
The World Wildlife Fund, or WWF, says about 20,000 rhinos live in South Africa. That is more than 80 percent of the rhinos in the world. Edna Molewa, South Africa’s environmental issues minister, says, “During 2014, we are sad to say this,1,215 rhinos were killed. This is a rise in the number of poached rhinos from 1004 in 2013 and indeed very worrying.”
The animals are hunted for their horns(犀牛角). Many people in Asia believe the horn has curing power, which drives poachers, at all costs, mad for more horns. But there is no scientific evidence for this belief. The horn is made of keratin. That is the same thing as human hair, fingernails and toenails.
Ms. Mo1ewa said 386 suspected poachers were arrested last year, an increase from the year before. But rhino protection workers say poachers often go unpunished after arrest. South Africa’s legal system is ineffective. Ms. Molewa said more needs to be done and South Africa is taking strong measures to protect rhinos. The efforts include moving some of the animals to secret places in neighboring countries. “Now approximately 100 rhinos have been moved to neighboring states in the SADC region during 2014 and 200 more rhinos will be moved this year” Molewa said.
Jo Shaw, the rhino program manager at the WWF, said, “we’re talking about a loss of a hundred rhinos a month. Or more than three a day. We really need to see effective action not just at a national level but internationally.” She says officials should find the criminal groups responsible for the poaching and punish them. Government officials are to meet in Botswana in March at the Inter-governmental Conference on Illegal Wildlife Trade.
![](https://img.xkw.com/dksih/QBM/2016/3/25/1578858534477824/1578858534600704/STEM/132560b42e764544ba3442a7f056eb93.png?resizew=233)
1. What do we know about rhinos?
A.Half of the rhinos live in South Africa. |
B.Less than 1,000 rhinos were killed in 2013. |
C.The killing reached the highest point in 2014. |
D.There are only 20,000 rhinos left in the world. |
A.To get more keratin. |
B.To protect the farmland. |
C.To use them for decoration. |
D.To make money from horns. |
A.many criminal groups are well organized |
B.new laws are needed to punish the killers |
C.rhino protection needs international cooperation |
D.conferences about protecting rhinos are to be held every year |
A.Rhino protection has a long way to go. |
B.No one would like to buy horns in the future. |
C.The illegal killing of rhinos will soon disappear. |
D.Rhinos living in South Africa will move to other countries. |
【推荐1】Nowadays golf is a very popular game around the world and the golf course is usually Perfectly taken care of by the owners. When a golfer plays on any golf course, he or she expects the course has a lot of hazards(障碍区)like sands, woods, and ponds of water. There is one special golf course, though, where along with these hazards that stand still, the player must expect to compete against hundreds of moving hazards. The golf course is on Christmas Island. The island is an area of Australia in the Indian Ocean, the third largest ocean in the world, lying between Africa and Australia. The moving hazards are bright red, four-and-one-half-inch crabs, small creatures with five pairs of legs, carrying a shell.
Over 150 million of these brightly colored crabs live in the island’s rainforests. Every year, starting around November, the crabs migrate(迁徙), that is, they leave the rainforest and make their way to the ocean. They arrive at the coast after one to three weeks. But the males return to the rainforest earlier than the females, who return about half a month later after producing up to 100,000 eggs.
On Christmas Island there is a golf course which was built on the crabs, migration route. During the migration season, there are hundreds of red crabs moving on the course. The rules of the Christmas Island Golf Club say that all players must treat the crabs as they would treat any other hazard. They cannot move them, and they must play around them. If a walking crab happens to knock a ball while it is on the green, hitting it into a hole, the ball is considered “in”.
The golfers must compete against a moving hazard, and actually so must the crabs. People have built roads that run through the crabs’ migration route. Unluckily, up to two million crabs are killed by passing vehicles every year. People are trying to reduce the number by putting up “Crab Crossing’’ signs and closing certain roads during the migration season.
1. What do we learn about the red crabs according to paragraph two?A.They arrive in the rainforest in November. |
B.They spend most of their year in the ocean. |
C.The females spend two more weeks on the coast. |
D.The males start to migrate earlier than the females. |
A.can help protect the crabs |
B.will attract more golf players |
C.slow down the migration of the crabs |
D.are designed to help improve the Golf skills |
A.the crabs must face danger on the road |
B.the crabs are quite perfect moving hazards |
C.the crabs like competing against moving hazards as well |
D.the crabs should choose the right route and season for migration |
A.Funny Golf | B.Great Migration |
C.Crab Crossing | D.Crab Hazards |
【推荐2】The Food and Drug Administration, citing an epidemic of diet-related illnesses, released new guidelines on Wednesday aimed at reducing the amount of salt that Americans consume at restaurants, school cafeterias and food trucks, or when they are eating packaged and prepared foods at home.
The recommendations, issued after years of delay, seek to reduce the average daily sodium intake by 12% over the next 2 and 1/2 years by encouraging food manufacturers, restaurants and food service companies to scale back their use of salt.
That goal translates into 3,000 milligrams of salt — slightly more than 1 teaspoon — compared to the 3,400 milligrams that Americans typically consume in a day. America’s love affair with salty foods has been linked to alarmingly high rates of high blood pressure, a leading risk factor for heart attacks, strokes and kidney failure.
Much of the excess sodium that Americans consume, about 70%, comes from processed and packaged food and meals served at restaurants, according to researchers. The guidance will apply to 163 categories of processed and packaged food and provide different targets for, say, rye bread, salad dressing and baby food.
Nutritionists and public health experts praised the FDA for taking on the problem of excess sodium, saying the effort would help sharpen the public’s focus on the dangers of overindulgence and create pressure on food companies to reduce their reliance on salt as a cheap flavor booster.
But many said that voluntary measures were unlikely to move the needle very much. Some experts have suggested compulsory reductions, though they acknowledge that the food industry’s profit-chasing nature makes such measures unlikely at the federal level.
1. What’s the purpose of the new guidelines released on Wednesday?A.To reduce daily sodium intake. |
B.To reduce the alarming rates of some diseases. |
C.To reduce the consumption of packed and prepared food. |
D.To reduce food companies’ reliance on salt as a cheap flavor booster. |
A.3400 milligrams. | B.Less than 1 teaspoon. |
C.2640 milligrams. | D.3000 milligrams |
A.Raising the awareness of reducing the cost. |
B.Thinking more about the positive effects than the cost. |
C.Increasing their reliance on salt as a cheap flavor booster. |
D.Sharpening the public’s focus on the dangers of overindulgence. |
A.To be carried out. | B.To switch to a new place. |
C.To make some sort of progress. | D.To change something totally. |
【推荐3】The importance of reading literature often seems lost on many Chinese people. Even experts in education think that the first goal of education is to encourage a love of learning. There is therefore the possibility of something wrong with the way students are taught here.
Why should they read literature? Do stories have value compared with the reading and learning of facts? Studies show clearly that the most powerful ways of learning are by experience, action and doing experiments and taking risks. Yet there are so many important things to learn that cannot be learned in these ways: feelings, problem solving, danger and relationships, for example. Research into this has shown how deep reading is a valuable experience different to a learning of words or facts. Keen( 热心的) readers of -literature show a better understanding of others. Their abilities to make good decisions are raised. Young children who enjoy a parent reading stories to them show greater awareness(意识) when they reach school age.
The best schools do seem to provide a limited (有限的) chance to enjoy literature, usually about the Chinese classic stories but there is not enough "free" time for students. There are enough reading materials (材料). Chinese book shops are full of story books, and most of them are of good quality (质量) in terms of content,plot (情节) and language. Was there not a Chinese author who received a Nobel Prize for literature recently? There are moves in Chinese education to promote (提升) decision making and shared values. The value of literature is helpful to these as well as to the future of China.
1. What does the author think of the way students are educated in China?A.He is proud of it. |
B.He is interested in it. |
C.He doesn't quite accept it. |
D.He is confident about it. |
A.By experience. |
B.By taking risks. |
C.By reading deeply. |
D.By doing experiments. |
A.Reading literature helps develop good values. |
B.Chinese students like reading stories as they get older. |
C.Stories in Chinese bookstores are generally of poor quality. |
D.Chinese students have no chance to read enough materials. |
A.Literature is a kind of art. |
B.Reading literature should be valued. |
C.Good reading materials are in great need. |
D.Something is wrong with Chinese education. |