1 . Tiny, black-capped chickadees (北美山雀) have big memories. They store food in hundreds to thousands of different locations in the wild—and then come back to these places when other food sources are low.
Scientists have known that chickadees have incredible memory skills. That memory can be a matter of life or death for these birds when there are no enough food resources in colder months.
Some researchers thought that neurons called place cells (细胞) would explain these birds’ ability to remember where their food is stored. These cells are known to include information about where things are in space. But recently, Selmaan Chettih and his team found that each time a chickadee hides a seed (种子) in a specific location, a unique brain pattern appears—separate from place cells.
To observe this, Chettih and his team created special areas with lots of feeders filled with sunflower seeds. They put small flaps (片状下垂物) where birds could hide seeds.
The scientists tracked the activity in their brains. Each time a bird hid a seed under a flap, researchers saw a brief unique brain pattern appear—what they called the bar code. Different patterns appeared even if the birds hid many seeds in the same location. When the birds revisited these sites and retrieved the hidden seeds, the same bar code-like pattern appeared again, as though all the information about each location and seed were related to a unique brain pattern.
The researchers compared these memories to episodic memories in humans, which are memories of specific events or personal experiences. They’re important to how humans connect time, people, places and sensory information together.
Chettih says that this seed-hiding behavior has a clear pattern of activity, which may help researchers build a structure for how the brain creates and stores memories.
1. Why are memory skills necessary for chickadees?| A．Memory skills show their intelligence and learning abilities. |
| B．Memory skills can help them survive in colder months. |
| C．They need memory skills to identify different types of food. |
| D．They use memory skills to avoid being attacked by other animals. |
| A．Unique brain patterns appeared when chickadees hid seeds. |
| B．Chickadees’ memories were controlled by place cells. |
| C．Chickadees preferred hiding sunflower seeds. |
| D．Chickadees often hid many seeds in the same location. |
| A．Got back. | B．Gave up. | C．Repaired. | D．Designed |
| A．To compare chickadees and human memory skills. |
| B．To present a detailed description of chickadees. |
| C．To introduce a study on chickadees’ memory. |
| D．To provide readers with a way to improve memory skills. |
2 . A British company has proposed releasing a GM(genetically modified) strain of the diamondback moth (菱形斑纹蛾), which has been developed to help reduce the population of these vegetable-eating insects.
Male diamondback moths carrying a deadly gene would be released which would cause their off springs (后代) to die almost immediately. Then the fall in their numbers could help to increase crop yields for farmers.
Oxitec, the company which came up with the idea, hopes to begin trials next year but faces opposition from groups who say the untested technology could threaten wildlife and human health.
“Mass releases of GM insects into the British countryside would be impossible to recall if anything went wrong. Changing one part of an ecosystem can have knock-on effects on others in ways that are poorly understood. This could include an increase in different types of pests. Wildlife that feeds on insects could be harmed if there are changes to their food supply” said Dr Helen Wallace, the director of Gene-Watch UK, who has sat on government advisory bodies.
Hadyn Parry, Oxitec’s chief executive, said there was demand from farmers for the technology and that using GM insects to kill the pests that feed on food crops is better for the environment than chemical sprays. The firm, which is supported by grants from the taxpayer, is developing a number of GM insects that would be used in Britain and around the world to protect crops and combat disease in humans.
Oxitec has contacted the Health and Safety Executive (HSE) to ask what controls, if any, should be put in place around GM moth trials. A spokesman said that while its officials and advisers have discussed Oxitec’s plans, there is yet to be a formal application for a trial. Consequently the department has not reached a view on whether it should go ahead.
1. People strongly object to the idea mainly because they think _______.| A．the technology won’t be as effective as chemical sprays |
| B．the technology may bring about knock-on effects on insects |
| C．the technology won’t be well controlled |
| D．the technology may not be good for wildlife and human health |
| A．Disapproving. | B．Positive. | C．Doubtful. | D．Not mentioned. |
| A．struggle | B．avoid | C．fight | D．contract |
| A．Oxitec still hasn’t formed any plans to control the trials. |
| B．Oxitec has decided to begin the trial this year. |
| C．Taxpayers will not continue to support Oxitec’s research. |
| D．Farmers prefer GM insects to chemical sprays. |
1. Why did Miriam’s uncle give her some money?
| A．To pay for her school tuition. |
| B．To celebrate her birthday. |
| C．To reward her for her kindness. |
| A．It inspired Miriam and her mother to visit Africa. |
| B．It tells the abuse of elephants in Thailand. |
| C．It is about a boy’s campaign to save elephants. |
| A．By teaching people to make clay elephants. |
| B．By drawing pictures about elephants. |
| C．By making and selling baked goods. |
| A．She’s a teacher. |
| B．She’s an animal doctor. |
| C．She’s an artist. |
4 . Birders get nervous when they see landscapes covered in wind turbines (涡轮机). When the wind gets going, their blades (叶片) can turn around at well over 200km per hour. It is easy to imagine careless birds getting cut into pieces and wind turbines do indeed kill at least some birds. But a new analysis of American data suggests the numbers are negligible, and have little impact on bird populations.
Erik Katovich, an economist at the University of Geneva, made use of the Christmas BirdCount, a citizen-science project run by the National Audubon Society. Volunteers count birds they spot over Christmas, and the society gathers the numbers. He assumed, reasonably, that if wind turbines harmed bird populations, the numbers seen in the Christmas Bird Count would drop in places where new turbines had been built. Combining bird population and species maps with the locations and construction dates of all wind turbines, he found building turbines had no noticeable effect on bird populations.
Instead of limiting his analysis to wind power alone, he also examined oil-and-gas extraction (开采), which has boomed in America over the past couple of decades. Comparing bird populations to the locations of new gas wells revealed an average 15% drop in bird numbers when new wells were drilled, probably due to a combination of noise, air pollution and the disturbance of rivers and ponds that many birds rely upon. When drilling happened in migration centers, feeding grounds or breeding locations, bird numbers instead dropped by 25%.
Wind power, in other words, not only produces far less planet-heating carbon dioxide and methane than do fossil fuels. It appears to be significantly less damaging to wildlife, too. Yet that is not the impression you would get from reading the news. Dr Katovich found 173 stories in major American news media reporting the supposed negative effects that wind turbines had on birds in 2020, compared with only 46 stories discussing the effects of oil-and-gas wells.
1. What does the underlined word“negligible”in paragraph 1 mean?| A．Insignificant. | B．Inaccurate. | C．Inconsistent. | D．Indefinite. |
| A．Previous studies. | B．Relevant data. |
| C．Reasonable prediction. | D．Experiment results. |
| A．Oil-and-gas extraction has expanded in America. |
| B．Birds are heavily dependent on rivers and ponds. |
| C．Many factors lead to the decline of bird populations. |
| D．Well drilling poses a serious threat to birds' survival. |
| A．Wind turbines could share the sky with wildlife. |
| B．More evidence is needed to confirm the finding. |
| C．Wind power will be substituted for fossil fuels. |
| D．Wind turbines deserve wider media coverage. |
5 . Humans can make do with scarves, coats and gloves in cold weather. Some animals can hibernate (冬眠) for the winter. A new study finds that reptiles (爬行动物) and birds do something that is similar to hibernation, but a little different. In very cold weather, their body temperatures greatly drop into an energy-saving state in order to survive. The ability to thermoregulation (体温调节) for reptiles and birds is possible.
In Texas, where the city of Beaumont reached a low of 18 degrees Fahrenheit last month, it looked as if alligators (短吻鳄) had died of cold — yet alive in iced-over water. By ensuring their long noses stayed above the water line, the cold-blooded creatures were able to lower their body temperatures to survive the sudden short period of very cold weather. The process, in the case of cold-blooded animals like reptiles, is called brumation — it’s like a short state of hibernating. While in this state, reptiles become sleepy and they can go for a long time without eating or drinking. For example, alligators can be in brumation from just a few hours to months.
Like reptiles and mammals, birds can go into a state called torpor in order to save energy under very cold conditions. “Torpor is somewhere between a short sleep and hibernation,” said Justin Baldwin, a PhD candidate in biology at Washington University in St. Louis. Baldwin studied 29 species of hummingbirds living in Colombia. Researchers found that hummingbirds can enter into deep or shallow torpor, depending on several factors, including their size and weather conditions. In deep torpor, the birds are much more likely to be affected by disease. And what’s more, they would be easily harmed by their enemies.
Some bird lovers want to help the birds when they are in torpor. For example, the Bird Alliance of Oregon offers a few tips on how to keep the birds from danger.
1. What does the new study show?| A．Body temperature is important for animals. |
| B．Thermoregulation exists in reptiles and birds. |
| C．Reptiles and birds’ thermoregulation is unusual. |
| D．Body temperature drops greatly during reptiles and birds’ sleep. |
| A．They are active in brumation. | B．They are dead in cold weather. |
| C．They face extinction in cold weather. | D．They eat and drink nothing in brumation. |
| A．They can get enough sleep. | B．They may harm other birds. |
| C．They may waste plenty of energy. | D．They may be under threat. |
| A．Risks of animal hibernation. |
| B．His opinions of the study about birds. |
| C．Some detailed measures to protect the birds in torpor. |
| D．Other problems raised by cold weather. |
6 . One Saturday in June, I got off the train from Vienna at Altenberg station, in the midst of a gathering of bathers, such as often flock to our village at fine weekends.
I had gone only a few steps along the street and the crowd had not yet scattered when, high above me in the air, I saw a bird whose species I could not at first determine. It flew with slow, measured wing-beats, varied at set intervals by longer periods of gliding. It seemed too heavy to be a hawk; for a stork (鹳), it was not big enough and, even at that height, neck and feet should have been visible. Then the bird made a sudden turn so that the setting sun shone for a second full on the underside of the great wings which lit up like stars in the blue of the skies. The bird was white. By Heaven, it was my cockatoo (凤头鹦鹉)! The steady movements of his wings clearly indicated that he was setting out on a long-distance flight.
“What should I do? Should I call to the bird?” Well, have you ever heard the flight-call of the greater cockatoo? No? But you have probably heard pig-killing in the traditional method. Imagine the loudest long cry a pig could make, picked up by a microphone and amplified many times over by a powerful speaker. A man can imitate it quite successfully, though somewhat weak, by shouting at the top of his voice “O-ah”. I had already proved that the cockatoo understood this imitation and promptly “came to heel”. But would it work at such a height? A bird always has great difficulty in making the decision to fly downwards at a steep angle. To yell, or not to yell, that was the question. If I yelled and the bird came down, all would be well, but what if it sailed calmly on through the clouds? How would I then explain my song to the crowd of people?
Finally, I did yell. The people around me stood still, rooted to the spot. The bird hesitated for a moment on outstretched wings, and then, folding them, it descended in one dive and landed upon my outstretched arm. Once again I was master of the situation.
1. What was the author’s cockatoo like?| A．It looked like a hawk. | B．It was blue and shiny. |
| C．Its neck and feet were long. | D．It was white with great wings. |
| A．By waving at it quickly. | B．By singing a song loudly. |
| C．By screaming his head off. | D．By using a powerful loudspeaker. |
| A．Flew about. | B．Came back. | C．Came around. | D．Landed on the ground. |
| A．He knew birds very well. | B．He could speak with his bird. |
| C．He liked showing off in public. | D．He often surprised people around him. |
7 . Located in the Ouachita Mountains, Hot Springs National Park covers over 5,500 acres and was the first area of land in North America set aside by the government for amusement. To protect the hot springs and their surrounding environment, it was named as an official protected area in 1832. On March 4,1921, an act of Congress transformed Hot Springs Reservation into Hot Springs National Park, providing key protection to the area and improving its importance.
The main draw to this park is what it is named for, the hot springs. The springs hold an average temperature of 62℃. The most special aspect of the hot springs is that they have long been recognized for their usage in medicine, which can help improve blood circulation, reduce inflammation (炎症), and provide relief for muscle and joint pain. Visitors have the chance to experience the recovery power of these hot waters. Additionally, they can explore the park’s hiking trails, which wind through the scenic parks, offering breathtaking views of the surrounding landscape.
Unlike most national parks that are surrounded by wilderness, Hot Springs National Park is located in the city of Hot Springs, creating a unique mix of natural wonders and city life. Visitors can explore the park’s beautiful scenery, and then experience the charm of the city’s downtown area, with cultural attractions and historic landmarks. The city of Hot Springs offers various resting places, restaurants, shops, and other services that suit the needs of tourists.
Whether you want to experience hot springs, explore the hiking trails, or learn about the park’s fascinating past, it provides a memorable experience for visitors of all ages.
1. What do we know about Hot Springs National Park from paragraph 1?| A．It has been protected for a long time. | B．It is famous for its rich amusement activities. |
| C．It is the largest national park in North America. | D．It protects a large number of historical buildings. |
| A．They have great medical value. | B．They lie in the center of hiking trails. |
| C．They can keep a comfortable temperature. | D．They are surrounded by mountain landscapes. |
| A．It has unique natural wonders. | B．It is located in a wild area. |
| C．It combines nature with city life. | D．It offers cheaper service to tourists. |
| A．A tourist map. | B．A history book. |
| C．A scientific report. | D．A geographic magazine. |
There was once a town in the heart of America where all life seemed to live in harmony with its
Then everything began to change: mysterious illnesses swept the flocks of chickens; the cattle and sheep sickened and died. Everywhere was
No black magic, no enemy action had silenced the rebirth of new life in this stricken world. The people had done it
In fact, this town does not actually exist. I know of no community that has experienced all the things I describe. Yet every one of these disasters has actually happened somewhere. A dangerous threat has crept upon us almost unnoticed, and this imagined tragedy may
9 . Producing genuine tears on demand is one of the hardest parts of my job as an actress. Acting teachers will tell you that in order to cry on screen you need to summon up something personal—a fear, an inner secret, a sad experience—that taps into your deepest emotions.
This may sound strange, but the inner secret I use when I need to cry during a movie scene is the image of an elephant. It’s an image that haunts me, an image that will remain in my heart and mind for as long as I live.
Two years ago I visited Samburu National Reserve, a wildlife park in Kenya. There, on a guided walk through the bush, I saw my first dead elephant. Poachers had hunted down this magnificent animal before piercing her tough hide (兽皮) with poisoned spears. As if she already knew her fate, the elephant had walked through the bush, the toxins (毒素) coursing through her veins, until she found a quiet place to lie down. When I saw her, her body was lying in the dusty red soil. That moment, the sight of the dead mother and her mutilated (残缺的) body lying under the shade of the tree, changed something inside me. I remember crying for her as I thought about the cruelty and senselessness that had led to her death.
That’s why I’m supporting a new United Nations campaign against the illegal trade in wildlife, which is pushing many species—not just elephants—to the edge of extinction in every corner of the world. Under the banner “Wild for Life”, this campaign serves to raise awareness about the illegal trade in wildlife and encourage everyone to take action against these crimes. The time for tears is over. The time for action is upon us.
1. Why does the author mention producing genuine tears on demand in the first paragraph?| A．To emphasize it is hard to produce genuine tears on demand. |
| B．To indicate the importance of genuine tears to a successful film. |
| C．To introduce the topic. |
| D．To prove a point. |
| A．The elephant mother lied under a tree and died naturally. |
| B．The elephant was shot with poisoned spears by poachers and died. |
| C．The elephant already knew some poachers would kill her. |
| D．The elephant escaped to a safe place successfully. |
| A．Indifferent. | B．Anxious. | C．Sorrowful. | D．Cautious. |
| A．To raise awareness about the illegal trade in wildlife and encourage people to take action. |
| B．To help protect extinct wildlife species. |
| C．To criticize the illegal hunting and trade. |
| D．To stop the illegal trade such as ivory happening entirely. |
10 . Scientists have found a new way to break down a group of harmful chemicals very hard to get rid of. The discovery could help solve a dangerous and growing problem — how to clean up the pollution of “forever chemicals”.
The group of chemicals known as PFAS (全氟烷基物) are pretty amazing. They’re non-stick, waterproof, and oil proof. They don’t burn easily or dissolve (溶解) in water. So scientists got really excited when they were discovered. Businesses started putting PFAS in all sorts of products, from non-stick pans to waterproof clothes, and from fire-fighting spray to carpets that resist stains. Even things like food wrappers and floss for cleaning your teeth contain PFAS chemicals.
But after a while, scientists realized the same things that made the chemicals useful also caused a real problem — PFAS doesn’t break down in nature. It doesn’t dissolve in water or bum. Not even bacteria can break PFAS down. No wonder these chemicals are known as “forever chemicals”.
As a result, PFAS chemicals surge in the environment. The chemicals are found in air, water, and dirt around the world — and in animals and people. In the US, 97% of humans have PFAS in their blood.
Luckily, scientists in the US have now found a way to break down some PFAS chemicals. Their solution requires boiling PFAS with two other very common chemicals. These chemicals can be found in just about any laboratory.
Dr. Brittany Trang, one of the scientists involved, said she didn’t even want to test the idea at first. “I thought it was too simple,” she said. But the process worked.
The research involved 10 types of PFAS, including two of the most common kinds. That’s a big step. But there are over 12,000 different kinds of PFAS. It’s important to note that the new method can only break down PFAS chemicals that have already been collected. Figuring out how to remove PFAS chemicals from the environment and collect them remains a huge challenge.
1. What can we infer about PFAS chemicals from paragraph 2?| A．Scientists were so excited to invent them. |
| B．They were environmentally friendly at first. |
| C．They are really widely used in our daily life. |
| D．They have more advantages than disadvantages. |
| A．Increase fast. | B．Float everywhere. | C．Extend fully. | D．React quickly. |
| A．It’s already too late to get rid of them. |
| B．There’s still a long way to go about it. |
| C．The new method is too simple to work well. |
| D．It’s impossible to get them removed from the environment. |
| A．Say Goodbye to Forever Chemicals |
| B．PFAS Chemicals Are a Two-edged Sword |
| C．PFAS Chemicals Will Remain a Challenge for Long |
| D．Scientists Find a Way to Break down Forever Chemicals |
