Researchers have discovered a unique group of polar bears who’ve survived in the absence of sea ice: by hunting from the ice that breaks off glaciers (冰川). The bears live in southeast Greenland and are a genetically(基因地) distinct subpopulation, which suggests they’ve been separated from other polar bears for around 200 years, according to a paper published this week in Science.
“The findings show us how some polar bears might survive under climate change. but I don’t think glacier habitat is going to support huge numbers of polar bears,” said Kristin Laidre, a polar research scientist at the University of Washington. “There’s just not enough of it. We still expect to see large declines in polar bears across the Arctic under climate change.”
When temporary ice sheets form on the ocean during each fall’s freeze, the bears walk across it in search of food, often by sitting next to gaps in the ice and waiting for seals to come up for air. When the ice melts (融化) in spring, polar bears typically survive between 100 and 180 days without food until the ice forms again. As temperatures rise, however, that period is becoming longer, which is harming the bears and pushing them toward starvation. The bears living in southeast Greenland go even longer without sea ice—around 250 days. But they’ve been able to continue bunting during that period by using large pieces of ice that break off from glaciers into the water.
There are roughly 26, 000 polar bears remaining across the globe. Though the southeast Greenland bears have adapted to surviving in their surroundings, rising temperatures may ultimately cause their glacial ice to shrink, too. As Steve Armstrup, a scientist with Polar Bears International says, the study “is not some kind of effective rescue for polar bears”. While the southeast Greenland bears are able to hunt through glacial ice today, he says, “In the future, that will change unless we arrest the rise of global greenhouse gases.”
1. What do we know about the newly- found polar bears?| A．They exist in large numbers. | B．They have genetically changed. |
| C．They do better in hunting seals. | D．They survive longer without food. |
| A．Keeping global warming under control. |
| B．Moving many polar bears south. |
| C．Preventing glacial ice breaking. |
| D．Finding new habitats for polar bears. |
| A．Polar Bears Find New Opportunities |
| B．Polar Bears Suffer From Lack of Ice |
| C．Polar Bears Survive in Iceless Regions |
| D．Polar Bears Decline With Climate Change |
| A．Lifestyle. | B．Health. | C．Travel. | D．Environment. |
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【推荐1】As a student, I heard the line “graduate school is stressful” so many times that it began to bear no meaning:
Sure, there were campus resources that encouraged healthy behaviors, including deep thought, and the benefits of self-care, but self-care sounded expensive and time-consuming to me; I had work to do. And I was not a fan of deep thought: The thought of sitting still for 30 minutes only caused me greater stress. But one thing I couldn’t stay away from was walking my dog.
Tessa is a six-year-old lovely coonhound that I got as a gift to myself, for completing my undergraduate degree at the University of Rhode Island in Kingston. I first saw Tessa as a thin and little dog in a photo on the Internet. She was found, huddled up with her friends, in a deserted house in Alabama.
Because of Tessa, I took frequent walking breaks while studying for a master’s degree in public health at Yale University in New Haven, Connecticut. I discovered the best corners and crannies on campus, including the sloping grass land behind the school, filled with squirrels and sticks — a safe place for dogs. I found a tree accidentally with a swing, overlooking the Yale Peabody Museum of Natural History, which offered the best sunset view in town. On our daily walks, I found calm in the woods and quiet in the early morning enveloping the city streets.
Now, as I work from home, Tessa continues to help me deal with a lonely existence. Just like in graduate school, she demands that I stop working, however briefly, and accompany her on a walk. These forced breaks throughout the day take me away from my computer and help me to stay active, greet my neighbors and come back to work refreshed. And although I certainly haven’t escaped from stress, and I am still trying to find my footing in research, I will continue to make time for walks every day. I recommend it very much.
1. How did the author feel about a deep thought?| A．Anxious. | B．Time-consuming. | C．Disordered. | D．Encouraged. |
| A．Lovely. | B．Gifted. | C．Poor. | D．Courageous. |
| A．Tessa likes walking very much. |
| B．The Yale University is very beautiful. |
| C．Tessa is helpful in spending graduate school happily. |
| D．The author likes both the city and the university. |
| A．The author often feels lonely at home. | B．The author works hard but exercises less. |
| C．Both the author and the neighbors like Tessa. | D．Walking with Tessa benefits the author much. |
【推荐2】My folks bought their first house in the early 1940s after Dad got a better job in Marquette, Michigan. We lived just inside the city limits in what was still a rural area.
In the spring of 1948, when I was 6 years old, my parents bought a calf（小牛）to replace our cow, which had been killed the year before. So one day we drove to a local farm and returned with a white and brown calf we named Tubby.
We didn’t own a truck, so Tubby rode home in the backseat of Dad’s car with my 9-year-old brother, Steve, and me. As you can imagine, the trip was a lot of fun for us kids.
Later that summer, Mom thought it would be cute to take a picture of me sitting on Tubby’s back. All went well until the snap of the camera shutter sent Tubby charging off on a run, with me holding on for dear life.
I lasted for about 30 feet before I hit the ground. Mom was quick enough to shoot a follow-up picture, so we had photos of me both on and off Tubby!
When summer had passed, the day arrived for poor Tubby to fill our freezer. I must have been somewhere else with my Mom on the fateful day, because I have no memory of how it happened. All I knew was that the barn was empty, and that we had plenty of meat for dinners.
I hadn’t lived on a farm like my mother, so I didn’t understand that what happened to Tubby was not unusual. Livestock aren’t meant to be pets, and most farm kids know and accept that truth.
Whenever we had beef for dinner, I would tearfully, “Is this Tubby?” This went on for a couple of weeks until Dad had finally had enough and declared, “No more cows!” That made me feel a little better about poor Tubby.
1. The writer’s parents bought Tubby so that ____.| A．the family would have enough meat to eat |
| B．It would provide their children with milk. |
| C．they would have more cows in the future |
| D．they would no longer feel lonely on the farm. |
| A．Serious. | B．Strong-willed. |
| C．Careless. | D．Quick-minded. |
| A．Steve was not so fond of Tubby as his younger brother. |
| B．the author’s mom thought it natural to kill a cow for meat. |
| C．the author had much trouble with Tubby in the summer. |
| D．the author was pleased to see their freezer filled with beef. |
| A．pets | B．education |
| C．diet | D．animals |
【推荐3】Many people think the dinosaurs were the biggest animals that ever lived.They are wrong.The world’s biggest animal is still living and it lives in the ocean.It is called the blue whale.Blue whales can be as long as 30 metres and weigh as much as 1,000 kilos.The largest dinosaurs weighed only 500 kilos.
The whale is not only the world’s biggest animal,it is also one of the smartest.We know that whales can communicate with each other,although we do not know what they are saying.Perhaps one day we will learn how to communicate with whales,and then they will be able to tell us about themselves.
Although they live in the ocean,whales don’t lay eggs like fish do.They are mammals.They give birth to babies and produce milk inside their own bodies to feed them.Humans are also mammals.
There are lots of stories about whales,but perhaps the most famous story is MobyDick,which was written by an American writer named Herman Melville.In the book,a sailor named Captain Ahab spends a lot of time trying to find and kill an enormous white whale named Moby Dick.
Sadly,there are not many kinds of whales left.People have killed them for food and other things for thousands of years.However,there are now laws(法律) to stop people killing most kinds of whales.So perhaps there will be more of them in years to come.
1. Whales can .| A．tell us about themselves |
| B．lay eggs |
| C．communicate with each other |
| D．live on the land |
| A．a story written by Herman Melville |
| B．a sailor |
| C．the name of a blue whale |
| D．a famous dinosaur |
| A．they don’t lay eggs | B．people have killed them |
| C．they live in the ocean | D．there are laws against them |
| A．the world’s biggest animal |
| B．lots of stories about whales |
| C．laws to stop people killing whales |
| D．the differences between dinosaurs and whales |
【推荐1】Life today is much easier than it was hundreds of years ago, but it has brought new problems. One of the biggest is pollution. Pollution comes in many ways. We see it, smell it, drink it and even hear it.
Men have been polluting the earth. Many years ago, the pollution was not so serious because there were not so many people. When the land was used up or the river was dirty in one place, men moved to another place.
Air pollution is now the most serious. Air makes people sick. And lots of people now are trying to use something to clear the air. Water pollution kills our fish and pollutes our drinking water. Noise pollution makes us become angry more easily.
Many countries are making rules to fight air pollution. They stop people from burning coal in houses and factories in the city, and from putting dirty smoke into the air.
Pollution by SO2 is now the most dangerous kind of air pollution. It is caused by heavy traffic. It is true that if there are fewer people driving, there will be less air pollution.
Although most of the pollution is caused by us, we are the ones who can change the situation. The earth is our home. We must take care of it. And we must pay more attention to the information in pollution at the same time.
1. Why was the pollution in the past less serious?| A．Because life in the past was easier. | B．Because there were not so many people. |
| C．Because men stayed in one place. | D．Because people used less coal to make fire. |
| A．Air pollution. | B．Noise pollution. |
| C．Light pollution. | D．Water pollution. |
| A．Try to use something to clear the air. | B．Ask people to use public transport more. |
| C．Stop putting dirty smoke into the air. | D．Encourage people to move to another place. |
| A．To prove life is much easier today. | B．To call on us to take care of our earth. |
| C．To show the danger of pollution. | D．To introduce how to fight air pollution. |
【推荐2】Humans are driving climate change. That means we can change our path.
Extend product lifespan (寿命).
Switch to electric cooking. Not only is gas-powered cooking releasing harmful chemicals into the environment, but it could be contributing to health problems for you if you’re cooking indoors.
Plant trees where you can. Trees can help control temperatures and improve air quality.
| A．Eat more sustainably |
| B．Fix what you have instead of replacing it |
| C．The time it gives you back this fall is an added bonus |
| D．As climate change causes temperatures in many areas to rise |
| E．Just make sure the plants you’re adding are approved for your area |
| F．Plus, research has shown some gas stoves can leak pollutants even when they’re off |
| G．While governments and businesses have a key role to play in addressing climate change |
【推荐3】The kakapo is the world’s heaviest and only flightless parrot. Now, some scientists are using advanced technology to rescue the endangered kakapos. If successful, the techniques used may help save other bird species as well.
The few remaining kakapos live on three small islands, where their progress can be monitored through a smart device. Once found in large numbers across New Zealand, the cute bird, which can weigh up to 11 pounds (5 kilograms), is now heading to extinction. While cruel predators (捕食者) such as foxes, cats, and snakes are largely to blame, the kakapo’s strange habits of laying eggs don’t help either. For starters, the parrots, which can live up to 100 years, do not start laying eggs until the age of five.
Scientists have set up individual feeding stations for all the birds to keep track of how much they eat. Given the difficulties to increasing the population, it is not surprising that only 114 adult parrots remain. Though the number is low, it is a great improvement over the 51 kakapos that remained on Earth in 1995. The increase of its population results from the government’s decision to remove the 51 birds to three small predator-free islands off the coast of New Zealand, and the efforts of a team led by Andrew Digby, a kakapo scientist for the New Zealand Department of Conservation.
A four-day-old kakapo chick will receive a health check. Young chicks in nests are examined and weighed every night, to ensure they are healthy.
Once the birds lay eggs, the eggs are carefully moved from the nests and taken to a hatching (孵化) room to hatch. “We tend to be more successful at raising kakapo eggs than the kakapo,” says Digby. “We break less of them. ” Once the eggs hatch, each mother is given only one chick, while the rest of the newborns are hand-fed (人工喂养). This helps ensure they all receive enough food.
1. What makes the kakapo unique in the parrot family?| A．Its food. | B．Its way of hatching. |
| C．Its feather. | D．Its flightless heavy body. |
| A．The way it feeds the young. | B．The environment it needs to live in. |
| C．The nature of its natural enemies. | D．The cause of its being endangered. |
| A．Giving the kakapos a new home without natural enemies. |
| B．Setting up individual feeding stations for the kakapos. |
| C．Building a fence to keep the predators away. |
| D．Driving all the predators nearby away. |
| A．To help the mother kakapo keep laying eggs. |
| B．To make every chick get enough food to survive. |
| C．To protect the mother kakapo from the predators. |
| D．To protect the chick from being killed by accident. |
The following experiment is an easy one that you can do at home. But make sure that you are supervised, because you will need to use matches. Now for the experiment！
What you need
•A hard-boiled egg without the shell
•A bottle with a neck slightly smaller than the egg
•A piece of paper
•A match
Method
1） Check that the egg will sit firmly on the neck of the bottle.
2） Tear the paper into strips and put the strips into the bottle.
3） Light the paper by dropping a burning match into the bottle.
4） Quickly sit the egg on the neck of the bottle.
Result
Astonishingly, the egg will be sucked into the bottle. Your friends will be amazed when you show them the experiment. But be careful when you handle matches.
Why it happened
As the paper burns, it needs oxygen and uses up the oxygen (air) in the bottle. The egg acts as a seal in the neck of the bottle, so no more air can get inside. This reduces the air pressure inside the bottle. The air pressure must equalize, so more air from outside must enter the bottle. The outside air pressure against the egg and then the egg is pushed into the bottle! This proves that air is all around and that it is pressing down on it.
1. Why is there the need to take care when you are doing the experiment?
| A．The bottle could break. |
| B．You need to light the paper with a match. |
| C．The egg needs to be shelled. |
| D．The egg has to be perfectly placed on the neck of the bottle. |
| A．equalize the air pressure inside and outside |
| B．make a seal in the neck of the bottle |
| C．finish up the oxygen inside the bottle |
| D．produce more oxygen inside the bottle |
| A．The oxygen inside the bottle sucked the egg in. |
| B．It became saft without the shell. |
| C．The neck of the bottle was wide enough. |
| D．The outside air pressure forced it into the bottle. |
| A．water pushes on your body when you swim underwater. |
| B．the earth is surrounded by a layer of air called the atmosphere. |
| C．the pressure of air around us has a powerful force. |
| D．the air pressure is not equalized around us. |
【推荐2】There is a cute animal living in the rainforest of Central and South America. Hanging out in the trees is its regular routine. It eats plenty of leaves every day to maintain its body temperature, keeping its organs working. It has three toes and walks slowest. The giant panda is second slowest, and two-toed sloths (树懒) come in third. People are curious about why they walk slowest.
Three-toed sloths rely on leaves merely. They have evolved finely tuned strategies for coping with this restricted diet. Firstly, they get as much energy from their food as possible. Secondly, they have a multi-chamber stomach that takes up a third of their body. Thirdly, they can spend five to seven days, or even weeks, processing a meal.
The other distinguished feature of three-toed sloth is that they use as little energy as possible. They spend most of their time eating, resting or sleeping. They get down from the treetops once a week for a bathroom break. When sloths do move, it is not very fast. It would take a sloth about five minutes to cross an average neighborhood street.
This unhurried approach to life means that sloths don’t need very much muscle. In fact, they have about 30% less muscle mass than other animals of their size. They also use less energy to keep themselves warm because their body temperature can change by about five degrees Celsius, less than a cold-blooded reptile, but more than most mammals. These physical and behavioral adaptations minimize the sloth’s metabolic rate (新陈代谢率). Three-toed sloths have the slowest metabolism of any mammal.
Moving slowly has allowed sloths to grow in their treetQp habitat. But it also made the sloths themselves a great habitat for other organisms, including algae (藻类), which provides a little extra camouflage (保护色) and maybe even a snack.
1. What similarity do sloths and pandas have?| A．Walking slowly. | B．Living in the rainforest. |
| C．Having identical appearances. | D．Enjoying eating bamboo leaves. |
| A．They frequently get down from trees. | B．They have rather small stomachs. |
| C．They eat a variety of foods. | D．They digest food slowly. |
| A．Their physical movement is faster than a cold-blooded animal’s. |
| B．Their temperature is lower than other mammal’s of their size. |
| C．Their muscle mass is more than other animals’. |
| D．Their metabolism is the slowest of reptile’s. |
| A．Why do three-toed sloths walk slowly? | B．Where is the habitat of three-toed sloths? |
| C．What is the eating habit of three-toed sloths? | D．When will three-toed sloths come down from trees? |
You’re on your way to school as usual when suddenly an invisible barrier appears out of nowhere, trapping you underneath it and isolating you from the outside world. What do you do?
This is the scary experience the residents of a fictional town called Chester’s Mill are going through in the US TV series Under the Dome. Based on famous US author Stephen King’s 2009 best-selling novel, the show has become “the highest-rated summer show in 21 years” since debuting (首播) on June 24, reported the New York Post.
The series begins with the dome (穹顶) making its alarming appearance. As the earth trembles and birds take off, an enormous, invisible barrier slices down, cutting the town off from the rest of the world.
The residents quickly realize they are trapped, probably for quite some time. Families are separated, emergency services are unreachable and water, food and fuel are strictly limited.
There is no way out or in. But who or what is responsible? Nobody knows. Thus, the residents are at the mercy of unknown forces and their internal conflicts.
While it provides an enjoyable TV thrill ride, the movie’s science fiction is closely linked with reality.
“Not only is it worrying, suspenseful (悬疑的) and full of splendid special effects, but it has big thoughts about environmentalism and the future of the commented The Denver Post planet.”
As King himself explained to The Telegraph: “The dome is a microcosm (微观世界) of life. We all live under the dome. We live on this little blue planet and so far as we know that’s all we’ve got,” he said. “The resources that we’ve got are the resources that we’ve got; they’re limited.”
But the show explores many themes in addition to environmental destruction. It also shows “how quickly the social order we take for granted can disappear when people are isolated and afraid”, said the Los Angeles Times.
It is “a science-fiction social study”, said The Washington Post. “Once the people of Chester’s Mill realize they are indefinitely trapped without means of food supply, outside communication and power, their polite sense of small-town, American civilization begins to fall apart.”
1. The underlined word “isolating” in the first paragraph probably means _______.| A．separating | B．protecting |
| C．discouraging | D．distinguishing |
| A．the dome, which appears out of nowhere, doesn’t have huge effects on the residents’ lives |
| B．it takes a long time for residents to realize they are trapped by the invisible dome |
| C．because of the dome, the residents in the small town become more united and helpful |
| D．not knowing what has happened, the residents feel helpless against unknown forces |
| A．Because it is suspenseful and uses splendid special effects to reflect modern life. |
| B．Because it gets us to think about the future of the earth and the importance of environmental protection. |
| C．Because it attaches great importance to following the social order even in frightening situations. |
| D．Because the residents in the TV series live almost the same life as ordinary Americans do. |
