As a popular subject of study among evolutionary ecologists, the three-spined stickleback (三刺鱼) is known for their different shapes, sizes, and behaviors—they can even live in both sea water and fresh water, and under a wide range of temperatures. But what makes that?
The researchers tracked six populations of the fish before and after seasonal changes to their environment, using genome sequencing (基因组测序) . Seasonal changes result in great changes in habitat structure and balance of salt and freshwater, and only those fish able to tolerate these rapid changes survive into the next season.
“These changes probably resemble the habitat shifts experienced by stickleback populations during the past 10,000 years, says Professor Barrett “We hope to gain insight into the genetic changes that may have resulted from natural selection long in the past.”
Remarkably, the researchers discovered the evidence of genetic changes driven by the seasonal shifts in habitats, which mirrored the differences found between long-established freshwater and saltwater populations. “These genetic changes occurred in independent populations over a single season, highlighting just how quickly the effects of natural selection can be detected,” says Professor Barrett, “the findings suggest that we may be able to use the genetic differences to predict how populations may adapt to the environment.”
The research emphasizes the importance of studying species in dynamic environments to gain a better understanding of how natural selection operates. In the further research, they plan to investigate how repeatable the observed genetic changes are, by testing whether they show up year after year. Doing so would demonstrate their ability to reliably forecast the evolutionary future of these populations.
1. What is paragraph 2 mainly about?A.The difficulties of the research. | B.The purpose of the research. |
C.The background of the research. | D.The methods of the research. |
A.Habitat shifts. | B.Genetic changes. |
C.Seasonal changes. | D.Independent populations. |
A.To know what natural selection is. |
B.To study species in dynamic environments. |
C.To test the reliability of the present discoveries. |
D.To forecast the evolutionary future of certain species. |
A.A science magazine. | B.A science fiction. |
C.An advertisement. | D.A novel. |
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【推荐1】Summer has finally arrived, which means kids are bound for the outdoors. It can be exciting for kids and parents to have a great opportunity to go swimming, picnicking or on adventures. This time of year is also a dangerous time of year as almost half of all injury-related deaths in children occur between May and August. Whether it be in the pool, on bike, out in the sun or in the backyard is always important. Here are some tips to keep the family safe over the summer.
Water Safety
At this time of year, drowning deaths among children skyrocket(飞涨) compared to the rest of the year. Never leave your child alone in the water, even in shallow water. A child can drown in as little as one inch of water. Enroll your children in swimming lessons. Some swim schools offer class for children as young as 6 months.
Sun Safety
We are fortunate enough to live in the Sunshine State, where sun shines year-round. But with all the time you and the kids will be spending outdoors this summer, it’s important to protect yourself. Make sure to use a widely-used sunscreen(防晒霜) that blocks both UVA and UVB sunlight. Cotton clothing has an estimated SPF of only 6, so even if your kids are going out wearing T-shirts and shorts, make sure they are covered up.
Bike Safety
Nothing says summer like a nice neighborhood bike ride. But bikes are not toys and can certainly cause injury. Don’t forget to always wear a helmet. Head injuries are reduced by 85 Percent when riders wear a helmet and other safety equipment like knee and wrist pads. It’s estimated that 75 percent of bicycle-related deaths could have been prevented with bicycle helmets. When riding on the street, make sure kids understand all riding hand signals, ride with the traffic flow and stay as far right as possible.
1. Summer is called a dangerous time because children .A.are easily injured |
B.enjoy staying in the sun |
C.want to learn swimming |
D.refuse to accept advice |
A.Kids only need to wear T-shirts and shorts. |
B.Bikes, like toys, seldom lead to injury. |
C.Some swim schools offer children class for free. |
D.Deaths from drowning increase suddenly in summer. |
【推荐2】The traditional Chinese lunar calendar divides the year into 24 solar terms. Major Snow, the 21st solar term of the year, begins this year on Dec 7 and ends on Dec 20.
Snowy winter
Appreciating plum blossoms
Plum blossoms usually flower in mid-to-late December in some southern cities of China, and sometimes bloom even earlier. The plum blossom is admired in Chinese culture for its toughness during severe winters.
Eating lamb
Lamb is a favorite food for Chinese people during Major Snow.
Eating porridge
Hot porridge could help warm you and nourish (滋养) your body in cold weather. In China, it’s customary to eat red bean porridge on the first day of Major Snow.
Preventing lung illness
During this period, Chinese people watch for outbreaks of lung illness, which can be prevented by properly drinking water. During Major Snow, it’s drier and colder, so people should drink more water. But you should not drink too much water at once.
A.In addition, there are other varieties |
B.People in southern China make sausages |
C.The snow falls at night and melts in the day |
D.Don’t drink cold water after exercise, either |
E.The snow in North China may last a whole day |
F.It’s excellent for protecting the body against the cold |
G.During this period, the temperature drops significantly |
【推荐3】Summer is a time to look forward to because there is no school to get you down.
●Read if you feel bored
Subscribe to a magazine or comic if you don’t like books. Choose whatever age-appropriate book that interests you and start reading. You can read anywhere. In your backyard or on your balcony, on your bed, or out by the lake.
●Get caught up on schoolwork.
Not all of us are straight “A” students. Take this time to go to the library and review material for the next year in advance.
●Travel.
●
If summers are hot where you live, you can go to the beach with your family or friends. Also, some water parks have great discounts at times during the summer. But be careful, if there’s a heat wave outside, you’d better stay out of the sum, or even go indoors.
A.Beat the heat. |
B.Reading doesn`t have to be boring |
C.Spend a lot of time outside. |
D.If you usually go on vacation in the summer |
E.Since it’s summer, you can do this at your own pace |
F.To have a good summer, you don’t have to do anything expensive. |
G.If you don`t have much time. |
【推荐1】Elephant Transit Home
In both Africa and Asia elephants are being threatened by changes in their natural habitats (栖息地). People are moving into the elephants’ habitats and endangering their survival. In the country of Sri Lanka, there is one place where elephants are not only protected but also respected. It is called the Elephant Transit Home (ETH).
Set up in 1995, the ETH aims to protect and nurture baby elephants that are found injured or living without their mothers in the wild. Every year about 30 baby elephants in Sri Lanka need help. As many as possible are brought to the ETH. There they are given food, shelter, and medical care. Most importantly, they are given the chance to be with other elephants and become part of a herd (象群).
A day at the ETH begins early in the morning when the baby elephants are given their first feeding of milk. During the day, each baby will drink an average of 13 gallons of milk. Older elephants are fed mostly coconut leaves and other native plants. Then the elephants are allowed to walk around, eating the grass and forming a herd. The cost of caring for the baby elephants is high. The ETH spends about $125,000 each year on powdered milk for the baby elephants.
At the ETH, workers try to reduce human connection with the elephants. They also try to increase bonds (联系) between the elephants. It usually takes three years for a baby elephant to be set free into its natural habitat. The elephants are sent back to the wild together with other orphans with whom they have bonded. This program helps them return to the wild as members of a herd that will communicate with each other and take care of each other.
The ETH is considered one of the best animal protection sites in the world. Not only are the elephants cared for, they are treated with respect. Most importantly, they go back to live in the wild, where they belong.
1. What does the underlined word “nurture” in Paragraph 2 mean?A.Set free. | B.Relate to. | C.Focus on. | D.Care for. |
A.It changes elephants’ habitats for the better. |
B.It receives about $125,000 each year. |
C.It helps to keep baby elephants safe. |
D.It protects 30 elephants every year. |
A.To study them better in a natural environment. |
B.To help them make it in the wild as a herd. |
C.To provide them with more living space. |
D.To train them to stay away from hunters. |
A.To introduce an animal protection site. |
B.To show the ways of wildlife protection. |
C.To explain the threat baby elephants face. |
D.To persuade the readers to protect elephants. |
When Brantley Harrison and her family rescued a tiny, injured squirrel back, then released her back into the wild, they didn’t expect to ever see her again. Nine years later, however, little Bella, they called the squirrel Bella, still comes to visit them almost every day—as long as snacks are provided, of course.
As a baby, the terrible attack made by an owl (猫头鹰) left Bella near death, she was carefully taken in by the Greenville County, South Carolina family, and raised by them alongside three other squirrels named Larry, Curly, and Moe. Bella stayed with the Harrisons until she had healed successfully thanks to a regular diet of fruit, nuts, and baby food, and was ready to jump on the trees in the forest. The sweet squirrel never goes too far from her adopted home, though, and stops by to say hello whenever she can, despite how much time has passed.
“Bella sits right at the front door waiting for someone to notice she has come by for a visit. If no one notices her, she will jump over to the dining room window to wait for someone to see her,” Brantley told The Dodo. The little lady just isn’t ready to part with the family that succored her life. Whenever she stops by, she asks for nothing more than a handful of nuts.
What is the most amazing part? A few years after Bella’s original stay at the Harrison house, she found her way back to them with an injured foot—and a belly full of babies—spending another few months of recovering. “It was truly amazing to watch the baby I raised raise her own babies,” Brantley said. Bella now even has her own Instagram page, where her human family documents her adventures, with almost 4 thousand followers!
1. What happened after little Bella was injured by an owl? (No more than 10 words)2. How did the Harrisons take care of little Bella? (No more than 15 words)
3. What does the underlined word in the third paragraph mean? (Only 1 word)
4. What brought Bella back to the Harrisons a few years after its original stay? (No more than 10 words)
5. How does Bella’s story inspire you? Please explain in your own words. (no more than 20words)
【推荐3】Like humans, animals need sleep too. A big problem for animals in the wild is keeping their enemies away while they sleep. Animals take care of this problem in different ways.
Anolis lizards live in many areas including tropical rainforests. They often sleep on leaves at the end of long branches. A leaf might seem like a strange bed, but it works like an alarm. If a hungry snake wiggles a branch, the lizard wakes up and leaps to safety.
Chimpanzees take their sleep very seriously. Each day, a chimpanzee builds itself a new, comfortable bed to sleep in. Scientists believe chimpanzees carefully choose a tree that is strong, where they build a nest using branches and leaves.
Parrotfish live among coral reefs in oceans. Every night, parrotfish usually sleep close to the rock in sheltered places. Some parrotfish go one step further by quickly making a slime layer that covers their whole body. This covering acts like a sleeping bag that provides a barrier against danger.
Bottle-nosed dolphins need to sleep, but they have to be on the ocean’s surface to breathe. They also need to watch over their young. What do they do? While half of the dolphin’s brain sleeps, the other half stays awake. After a while, the sleeping half wakes up while the other half snoozes.
Sooty terns have the most amazing sleep. They nest on islands. When they arc not nesting, they live for many years in the sky and on the sea’s surface. When and where can they sleep? Scientists believe they are able to sleep while they are flying, staying out of the reach of enemies.
1. Which animals need the most preparation before sleep?A.Anolis lizards. | B.Chimpanzees. | C.Parrotfish. | D.Sooty terns. |
A.Quietness. | B.Time length. | C.Comfort. | D.Safety. |
A.biography | B.tourist brochure | C.science fiction | D.popular science magazine |
【推荐1】You may not pay much attention to your daily elevator ride. Many of us use a lift several times during the day without really thinking about it. But Lee Gray, PhD, of the University of North Carolina, US, has made it his business to examine this overlooked form of public transport. He is known as the “Elevator Guy”.
“The lift becomes this interesting social space where etiquette (礼仪) is sort of odd,” Gray told the BBC. “They are socially very interesting but often very awkward places.”
We walk in and usually turn around to face the door. If someone else comes in, we may have to move. And here, according to Gray, lift users unthinkingly go through a set pattern of movements. He told the BBC what he had observed.
He explained that when you are the only one inside a lift, you can do whatever you want – it’s your own little box.
If there are two of you, you go into different corners, standing diagonally (对角线地) across from each other to create distance.
When a third person enters, you will unconsciously form a triangle. And when there is a fourth person it becomes a square, with someone in every corner. A fifth person is probably going to have to stand in the middle.
New entrants(新进入者) to the lift will need to size up the situation when the doors slide open and then act decisively. Once in, for most people the rule is simple – look down, or look at your phone.
Why are we so awkward in lifts?
“You don’t have enough space,” Professor Babette Renneberg, a clinical psychologist at the Free University of Berlin, told the BBC. “Usually when we meet other people we have about an arm’s length of distance between us. And that’s not possible in most elevators.”
In such a small, enclosed space it becomes very important to act in a way that cannot be construed (理解) as threatening or odd. “The easiest way to do this is to avoid eye contact,” she said.
1. According to Gray, when people enter an elevator, they usually _____.A.try to keep a distance from other people |
B.look around or examine their phone |
C.make eye contact with those in the elevator |
D.turn around and greet one another |
A. | B. |
C. | D. |
A.ignore | B.make the best of |
C.put up with | D.judge |
A.someone’s odd behaviors |
B.their unfamiliarity with one another |
C.the lack of space |
D.their eye contact with one another |
【推荐2】Kim Jae-geun, a softly-spoken 59-year-old man in South Korea, had spent many years in advertising before he no longer had the strength for it. So during the past seven years, instead of spending his days writing copy, Mr. Kimhas spent his evenings behind the counter of his bar, Seochon Blues, near Seoul’s government district. The place is also home to thousands of vinyl records (黑胶唱片) that he began collecting as a teenager. Customers can request their favourite songs there. The bar is often full of tired office workers, and 20-something people and local artists at weekends. “There’s a special wave,” Mr. Kim observed. “All the young people ask for very old songs.” he said.
Mr. Kim’s Seochon Blues is one of the dozens of “LP bars” in South Korea’s capital, many of which are run by men with similar stories. South Korean companies offer few opportunities to middle-aged workers who haven’t climbed through the ranks. Leaving their jobs in their fifties, with music collections becoming too large for their living rooms, a few who haven’t taken up work as taxi drivers or security guards began to make a living by opening such bars.
The first LP bars opened in the 1990s, possibly inspired by the “listening bars” that originated in mid-20th century Japan. Music enthusiasts would come to these bars to listen to imported records that were otherwise hard to come by. The LP bars have proliferated in recent years with more and more people loving going there, thus greatly benefiting the middle-aged owners.
All LP bars encourage nostalgia (怀旧). “I don’t like digitization or the isolated way people have now,” said Lee Jae-jun, who left his job and also opened such a bar. He likes recalling the eighties and nineties and playing songs from people’s youth. “On the best days, regulars arrive for just one drink, and then I play old songs they like. And before you know it, it’s midnight and everyone goes home, drunk and happy,” said Lee Jae-jun.
1. What appears unusual for Mr. Kim in Seochon Blues?A.Teenagers collect different types of vinyl records. |
B.The youth enjoy listening to old songs. |
C.Artists try to get inspiration for writing songs. |
D.People show off their success in advertisements. |
A.Middle-aged workers are welcomed by small companies. |
B.South Koreans prefer to live a quite relaxed life. |
C.South Koreans tend to change their jobs constantly. |
D.LP bars offer career opportunities to middle-aged workers. |
A.Sprung up | B.Survived. | C.Died down. | D.Returned. |
A.Amazing and professional. | B.Romantic and enjoyable. |
C.Nostalgic and relaxed. | D.Mysterious and encouraging. |
A.The stories behind Kim Jae-geun | B.The rise of LP bars in South Korea |
C.The popularity of music bands | D.The influence of old records |
【推荐3】Seamounts are mountains, usually volcanoes, which rise up from the sea floor. Some of the volcanoes are extinct; some are still active. But they are hard to find for the reason that they do not reach the surface of the water. Scientists say seamounts cover nearly 29 million square kilometers of this planet under the sea. Marine life gathers at seamounts because they carry nutrient-rich water upward from the sea floor.
In September, a group of scientists set out to explore Cook Seamount which rises almost 4,000 meters from the Pacific Ocean floor about 160 kilometers off the island of Hawaii. Never have humans seen it up close before.
Three people went in a submarine down to over 900 meters below the ocean surface to the top of the seamount. As the blue waters became darker, underwater creatures that chemically create their own light began to swim past the submarine. The scientists found several kinds of deep sea corals, including a possible new species of coral they named “Purple Haze”, on the seamount’s sides.
Conservation International and the University of Hawaii worked together for the trip to Cook Seamount. Greg Stone, the lead scientist, said, “This three-day research is the start of an effort to survey seamounts throughout the Pacific Ocean over the next five years, and we hope to study a total of 50 seamounts.” He said humans have little knowledge about seamounts, but they are a “key part” of what drives the ocean. Stone said he wanted to find out what is living on the seamounts and how they support ocean life. From that, he says, we will understand ocean health, which relates directly to human health.
M. Sanjayan, Executive Vice President of Conservation International, said there were 10,000 or maybe 100,000 seamounts across the world’s oceans and because most had not been explored, he expected they would see things new to science.
One of the other two seamounts studied on their trip was Lo’ihi, an active volcano, which has been studied over the past 30 years. The scientists saw an “old friend” on it-a shark they had seen there before. Scientists say volcanic activity of Lo’ihi pushes the seamount upward. But do not look for it to break the surface of the water any time soon.
1. Why is it difficult to find seamounts?A.Because there are too few seamounts. |
B.Because they can’t be seen above the sea. |
C.Because it’s dangerous to get close to seamounts. |
D.Because many seamounts are not high. |
A.There is no sunlight around the top of Cook Seamount. |
B.Scientists found some new species on Cook Seamount. |
C.The height of Cook Seamount is about 900 meters. |
D.Underwater creatures can create their own light. |
A.They will study 10 seamounts every year. |
B.Their survey aims at 50 seamounts around the world. |
C.They know little about how seamounts influence the ocean. |
D.They want to find out how ocean health relates to human healt |
A.Lo'ihi is a new discovery during that trip. |
B.Lo'ihi is the only active volcano under the Pacific. |
C.Lo'ihi may become an island many many years later. |
D.Lo'ihi must have had volcanic activity in recent years. |
A.Undersea Creatures and Seamounts |
B.New Discoveries Under the Ocean |
C.Scientists Surveyed the Creatures In the Sea |
D.Scientists Explored Seamounts |
【推荐1】Because of a record drought, the Amazon River drops to the lowest level ever recorded. Smaller river systems that feed into the Amazon River have been drying up, leaving boats stranded (搁浅) and people in remote villages with very little food and water. The port of Manaus, where the Amazon River meets with the smaller river Rio Negro in Brazil, recorded 13.59 m of water on Monday compared to 17.60 m a year ago. That was the lowest level since records began in 1902. It was said the drought had affected 481,000 people so far.
The Brazilian government has blamed the drought on the El Nino climate pattern, which has brought hotter and drier weather. The government said it was expected the drought would last until at least December, when El Nino’s effects are forecast to reach the highest point.
The drought has made it hard to access food, drinking water and medicines, which are usually transported by river. After months without rain, some rainforest villagers were relieved when a Brazilian charity delivered supplies to their community. Some areas could still be reached by canoe, but many boats hadn’t been able to bring supplies along the river and a lot of supplies were being delivered by tractor. The drought also affected the cleanliness of the village’s drinking water. As a result, many children were getting ill and often having fever. Villagers said it wasn’t very good for them because they were practically isolated (隔绝).
El Nino has also affected the animals of the river. More than 100 endangered river dolphins are thought to have died because of high water temperatures. The Amazon rainforest represents about half of the remaining rainforest left on Earth and is home to more than one million species, or a third of all known land plants, animals and insects. About 150—200 billion tons of carbon is stored in the Amazon rainforest, making it important for the health of the whole planet.
1. What can we learn from paragraph 1?A.Water level in Manaus hit its lowest in over a century. |
B.The Amazon River has been drying up and disappearing. |
C.It is important for the global fight against climate change. |
D.It forces villagers living in the rainforest to leave their homes. |
A.Optimistic. | B.Concerned. | C.Content. | D.Uncaring. |
A.It contains almost all of the world’s fresh, flowing water. |
B.It will cause the widespread droughts around the world. |
C.It is important for the global fight against climate change. |
D.It forces villagers living in the rainforest to leave their homes. |
A.The Ecosystem of the Amazon Rainforest |
B.The Importance of the Amazon River |
C.The Amazon River and Its Rainforest |
D.The Lowest Level of the Amazon River |
【推荐2】Adverse impacts on health due to extreme weather and vector-borne disease risks could increase in the United Kingdom (UK) under a warming climate, according to a report published on Monday by the UK Health Security Agency (UKHSA).
The report, written by 90 experts, is based on climate projections using a high-end warming scenario (可能发生的情况) or a “worst-case scenario” of approximately 4.3 degrees Celsius of warming by 2100. “Our changing climate poses one of the greatest health security and societal challenges, impacting everything from the air we breathe to the quality and availability of our food and water,” Isabel Oliver, chief scientific officer at UKHSA, said in a statement. The report estimates that there will be up to 10,000 deaths in the country by the 2050s as a result of extreme heat.
Based on a high-end warming scenario, the report anticipates a substantial surge in heat related deaths, with an increase of over 1.5 times by the 2030s and an over 12-fold rise by the 2070s. It also states that vector-borne diseases, such as chikungunya, dengue and Zika viruses, could become transmissible in London and other parts of the UK due to more Aedes albopictus (Asian tiger mosquitoes) and Culex mosquitoes.
The report also warns that more people will be at high risk of flooding in the future due to changing rainfall patterns.
“Action is needed now to adapt our policies, environments and our behaviors to secure health, well-being and livelihoods,” Oliver said, adding that much can be done to “avert (避免) and prevent” the impacts of climate change on health.
UKHSA, an executive agency sponsored by the Department of Health and Social Care, is responsible for planning, preventing and responding to external health threats.
This year is set to be the hottest year on record in human history, according to a report published by the United Nations World Meteorological Organization (WMO) at the 28th meeting of the Conference of the Parties to the UN Framework Convention on Climate Change.
1. What is the author’s purpose in writing this passage?A.To introduce the warming climate. |
B.To remind people about the harmful impacts on health under climate change. |
C.To help people get rid of external health threats. |
D.To display UK’s dependence on food. |
A.Availability of our food and water caused by high-end warming scenario. |
B.10,000 deaths caused by vector-borne diseases. |
C.Flooding in the future caused by varied rainfall patterns. |
D.Transmissible vector-borne diseases caused by flooding in the future. |
A.A smooth drop. | B.A sharp decline. | C.A small growth. | D.A massive rise. |
A.Increasing food supplies. |
B.Averting and preventing the climate change. |
C.Adjusting the policies, environments and people’s behaviors. |
D.Planning, preventing and responding to health threats. |
【推荐3】Since the beginning of the summer in 2022, China has been sweltering under the worst heatwave in decades. A number of people in Zhejiang, Jiangsu, and Sichuan provinces were diagnosed with thermoplegia (热射病), the most severe form of heatstroke, and some even died of this disease.
In a warming world, the hazards of heatwaves are increasing. “Over the past four decades, the main drivers of the large increase in heatwave-related deaths in China are the rapid increase in the frequency of heatwaves, followed by population growth, population aging, and rising baseline mortality (基线死亡率),” said Prof. Huang Cunrui, a researcher from Tsinghua University. According to a study, the number of deaths caused by heatwaves in China has increased rapidly since 1979, from 3679 persons per year in the 1980s to 15,500 persons per year in the 2010s.
High temperatures would accelerate the loss in soil moisture (水分). What’ s more, each additional degree of warming will increase crop losses to insects by 10 - 25 percent, threatening food security for billions of people. China has witnessed a range of extreme weather events, including heavy rainfall, flooding, tornadoes, and record heatwaves this year. Meteorological officials said the country had an average temperature of 21.3 degrees Celsius in June, 0.9 degrees Celsius higher than the same period on average, and the highest record for the same period since 1961.
Experts say that while extreme summer heat is not entirely new, these sorts of occurrences could be something that becomes a standard part of life, requiring people to start learning how to cope with heatwaves that may continue for the rest of summer and well into the future.
Remember that even healthy, young athletes can be harmed by extreme heat, so every activity should be evaluated when extreme heat hits. There are some ways to stay safe during extreme heat events, such as drinking plenty of water, looking for shade or remaining in shade when outside, and avoiding cooking large meals.
1. What is the major reason for the increase in heatwave-related deaths in China?A.The aging of the population. |
B.The higher frequency of heatwaves. |
C.The higher level of death rate. |
D.The increase of the population. |
A.By listing examples. |
B.By comparing statistics. |
C.By giving explanations. |
D.By referring to previous findings. |
A.The government should take measures to solve the extreme heat. |
B.The rare heatwave in summer is coming to an end. |
C.People may get accustomed to the extreme heat in summer. |
D.Extreme summer heat has never occurred before. |
A.Significance of being aware of the danger of extreme heat. |
B.Prediction of the extreme weather events in the future. |
C.Conclusion of the relationship between heatwave and health. |
D.Effective ways to protect people from heatwave. |