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? |
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【推荐1】Some animals enjoy playing just like humans do although researchers used to think that applied mostly to birds and mammals. An animal plays when it does something that doesn’t seem to be constructive to its survival so it’s not about food or shelter, for instance. The behavior is also often done again and again.
However, scientists have now conducted experiments that seems to prove bees play too. As far as the experts know, bees are the only insect to do so.
Researchers from Queen Mary University in London earned out an experiment in which bumble bees were taught to roll little balls with the aim of being rewarded with food. They then discovered the insects kept rolling balls even when they weren’t rewarded. They then did another experiment: a path was built from the beehive to a section containing food. Balls were placed on each side of the path leading to the food. The balls on one side were glued down and couldn’t move and the balls on the other side were free and capable of moving. The bees could stay on the path to get to their food, but they always went to the side of the moveable balls and rolled them along. One bee even rolled the balls 44 times in one day.
Researchers say the experiments may well show insects are more evolved than we think.
1. Which of the following best describes the animals’ behavior?| A．Recovered. | B．Repeated. | C．Responded. | D．Recommended. |
| A．The bees kept playing without reward. |
| B．The bees taught each other to roll balls. |
| C．The bees rolled little balls to get food. |
| D．The bees rewarded each other. |
| A．To show the balls were movable. |
| B．To show the bees enjoy food. |
| C．To show the bees enjoy playing. |
| D．To show the balls were important. |
| A．Insects’ evolution is out of control. |
| B．Insects’ behaviors are beyond imagination. |
| C．Insects’ behaviors are out of control. |
| D．Insects’ evolution is beyond imagination. |
【推荐2】You might know what to do if a human needs first aid, but what if your dog gets a bite or your cat eats something poisonous? Dr. Liam Donaldson, clinical director at Greencross Vet (兽医) Hospital at the University of Melbourne, says it’s important that pet owners understand basic first aid. Here, he shares his tips for dealing with common accidents and injuries.
Cuts & woundsYou don’t need to worry about disinfecting the injury site, but you do need to stop the bleeding, says Dr. Donaldson. “If there’s uncontrollable bleeding, apply pressure — even if it’s just using a T-shirt. Once you have applied pressure to reduce bleeding, take your pet immediately to a vet for assessment.” he advises.
Snake bitesSnakes have very small teeth, so their bite marks can be difficult to spot — and you might not see the bite happen. But if your pet shows signs of snake bite poisoning — sudden weakness and collapse, dilated pupils, vomiting, paralysis and shaking or twitching of muscles — get them to a vet without delay.
Tick bitesIt’s a good idea to have a pair of tick-removal tweezers (镊子) on hand in case you need to remove a tick from your pet. “There’s often a lot of concern about whether you have to get all of the tick or not, but as long as you get the body of the tick off, generally the head will just remove itself over time,” says Dr. Donaldson. He recommends keeping the tick so that if your pet becomes ill, your vet can identify whether they were bitten by a paralysis tick (the type that can be deadly).
PoisoningCats eating ivy and dogs eating sago palm or macadamia nuts are some of the most common poisonings Dr. Donaldson sees. “If it’s a macadamia nut, I would just keep a very close eye on them. If they start to show any gastrointestinal signs — if they go off their food, if they become sore in any of their legs — get them checked over by a vet,” he says. “If it was lilies or sago palm, I would recommend getting them to a vet, even if they’re not showing signs of illness, just because that can typically be life-threatening.”
1. If your pet dog gets seriously injured, what is the best solution?| A．To seek medical assistance. | B．To disinfect the injury site. |
| C．To apply pressure to reduce bleeding. | D．To use a T-shirt to stop bleeding. |
| A．Ivy. | B．Sago palm. |
| C．A macadamia nut. | D．A common poisoning. |
| A．A medical journal. | B．A biology textbook. |
| C．A hospital advertisement. | D．An animal care guide. |
【推荐3】Thousands of people around the world are helping to save the world’s biggest fish. By taking photos of whale sharks, those helpful citizens are providing researchers with critical information about whale sharks’ locations and migration routes.
Whale sharks are endangered, with their populations worldwide having decreased by more than 50% over the past 75 years. Although protected in many countries, they are still killed by the fishing industry—caught intentionally and accidentally, especially in tuna(金枪鱼) fishing areas where whale sharks and tuna swim close together. Whale sharks are also threatened by oil and gas drilling, ship strikes and climate change.
To help protect the species, Australian biologist Brad Norman co-founded The Wildbook for Whale Sharks, a photo identification database that went online in 2003. Photography lovers, scientists and whale shark tour operators around the world contribute photos of whale sharks to the system, which uses NASA technology to map their locations and track their movements. Today, the database holds over 70,000 photos from more than 50 countries.
Pictures submitted to The Wildbook are analyzed by scanning the spots on the animal’s skin, which are as unique as human fingerprint, says Norman. Then it identifies the shark by searching the database for a matching pattern. This way, they can figure out which whale shark is where.
The data on whale shark locations and migration routes help scientists make strategies to protect whale habitat. “It’s so important to have the public assist with our project.” says Norman . He hopes to see more people join to help find out where the whale sharks go to mate. Protecting their breeding(繁殖) grounds is the “one big thing” needed to save the species in the long run. The help from thousands of citizens gives him a better chance of making that possible.
1. What can we learn about whale sharks in paragraph 2?| A．They are sometimes caught by accident. |
| B．They are threatened by other fish species. |
| C．They change their migration routes a lot. |
| D．They often damage gas drilling platforms. |
| A．By photographing their unique skin spots. |
| B．By attracting sea creatures for them to hunt. |
| C．By comparing their body marks with stars. |
| D．By finding out their locations and movements. |
| A．Identifying the number of their species. |
| B．Making sure more of their babies safely born. |
| C．Building artificial breeding grounds for them. |
| D．Making more people aware of their existence. |
| A．Whale sharks are endangered |
| B．Find out the whale shark’s migration routes |
| C．The public help to save whale sharks through photos |
| D．Wildbook for Whale Sharks—a photo identification database |
【推荐1】If you follow any people who like traveling on Instagram, you’ve probably noticed they’ve posted amazing photos from Portugal in the last few years, especially during peak summer months. Mario Fernandes, a co-creator and the editor of Golisbon said he had seen increased interest in traveling to Portugal in the past five years, particularly in the last two or three. Cindy Goldberger, a travel adviser for Hiatus, an agency in Brooklyn, New York, said that she noticed an increase in Portugal trips about three years ago and that she gets more requests to plan people’s visits there every year. According to Reuters, the number of foreign tourists visiting Portugal hit a record for 2017, and in the same year the country won the world’s leading destination at the World Travel Awards.
Fernandes suggested it’s because Portugal is safe and more affordable than many other Western European countries. The country’s frequent sunshine is also attractive to many visitors. The Algarve, the southernmost area of Portugal, is home to “some of Europe’s most beautiful beaches,” according to Fenandes. Goldberger noted that many airlines have offered better routes to the country in recent years. She’s also a fan of the new hotels that have opened, including farms that have become hotels.
Eric Hrubant, the president of Cire Travel, noted that there is another reason. “It’s a small country, yet you have cities with rich history, culture and food, as well as a lot of beach and golfing options,” he said. “In five to 10 days, you can have a vacation or honeymoon that caters to all of your senses and desires.”
Hrubant pointed out that celebrities(名人) like Madonna and newlyweds Michael Fassbender and Alicia Vikander have moved to Portugal, which has put the country more popular.
So you don’t know where to go for a vacation this summer? Now you can make a better choice.
1. What does Paragraph 1 mainly say about Portugal?| A．It’s doing its best to attract tourists. |
| B．It’s been made popular by Instagram. |
| C．It’s become a popular tourist destination. |
| D．Its development depends on its tourism. |
| A．Lower expenses. | B．Convenient transportation. |
| C．Frequent sunshine. | D．Beautiful beaches. |
| A．upsets. | B．improves. |
| C．satisfies. | D．frightens. |
| A．To encourage people to visit Portugal. |
| B．To recommend some Portuguese trips. |
| C．To tell some basic facts about Portugal. |
| D．To explain why Portugal has become famous. |
【推荐2】In Wiltshire, England, volunteers are being sought to visit a nature protection area to count the butterflies living there and on surrounding fields.The project is promoted by an environmental protection organization, which has contributed to improving the living environment for wild animals.Recently the organization has issued an appeal to help it observe environmental changes based on the record of butterflies and protect the environment.
In the area, the local people have planted many special flowers with the help of the organization, aiming to see whether these flowers will interest the rare and beautiful butterflies.The project officer Sarah Marshall says, “It will be a suitable habitat (栖息地) for butterflies.They are great ‘indicator species’ as they are easily affected by climate changes so they make a brilliant early-warning system for the environment.” She also points out that volunteers are needed to record the number or species of butterflies, and based on the change happening to the butterflies, the hidden environmental problems in the area can be found out in time.
The organization is seeking volunteers to help monitor butterflies from April through to September. They will walk a fixed route and record the different butterflies they encounter along the way. Each visit should take no more than two hours, and each volunteer is expected to visit once a month to count the wildlife. “Staff will provide back up, so if the weather is poor on the day you are to visit (butterflies don’t like to fly in the rain, wind or if it’s too cloudy) we can have someone else do your job,” Sarah points out.
No previous experience is necessary as training and support will be provided, but a keen interest is essential. If you are interested please contact Sarah on (01380) 725670, ext 278, email sarah@ wiltshirewild- life.org.
1. According to Paragraph 1, what is the purpose of the project?| A．To appeal to more visitors. | B．To protect the environment. |
| C．To control butterfly population. | D．To expand the area for wildlife. |
| A．they can provide support for visitors. |
| B．they can give information to other species. |
| C．they are not easily found out in their habitats. |
| D．they are very sensitive to environmental changes. |
| A．having some special previous experience. |
| B．being interested in protecting the environment. |
| C．walking a regular route and do some recordings. |
| D．visiting the nature protection area once a month. |
| A．Visitors are being trained to identify butterflies. |
| B．Wildlife areas are being protected by butterflies. |
| C．Volunteers are being needed to count butterflies. |
| D．Organizations are being put up to protect butterflies. |
【推荐3】Golden Gate Bridge
Golden Gate Bridge Located in San Francisco, the Golden Gate Bridge started in the year 1933 to connect the San Francisco Peninsula with Marin County. It was finally thrown open to public in 1937. It cost more than S 35 million in the construction. Till the year 1957, the Golden Gate Bridge, at a length of 2, 737 meters, was the longest suspension bridge in the world.
Brooklyn Bridge
The Brooklyn Bridge is located in Brooklyn. It is one of the oldest bridges in the United States, opened in the year 1883. The length of the bridge is 1, 825 meters. The bridge has been featured in several Hollywood movies.
George Washington Bridge
Also known as the Hudson River Bridge, the George Washington Bridge which connects Fort Lee with Manhattan came into use in 1931 after a construction period of almost 4 years. It is a two-level suspension bridge.
Mackinac Bridge
This is the third biggest suspension bridge in the world at a length of 8, 038 meters. The architect of this bridge was Dr. David B. Steinman who directed the construction of the bridge which started in the year 1954 and opened to the public in 1957. People using this bridge are charged a certain amount of money.
Navajo Bridge
Located in Arizona, this bridge crosses the Colorado River and is almost 250 meters long.
The construction of this bridge started in the year 1927, ending two years later and costing＄390,000. In the 1990s a second bridge was built which was opened to the public in 1995. The first bridge is still used by pedestrians now.
1. What do we know about the Golden Gate Bridge?| A．It consists of two bridges |
| B．It takes about 4 years to complete the construction |
| C．It is the longest suspension bridge in the world. |
| D．It costs the least of the five bridges |
| A．Golden Gate Bridge |
| B．Navajo Bridge |
| C．George Washington Bridge |
| D．Brooklyn Bridge |
| A．See the statue of Dr David | B．Steinman. B.Use the second bridge |
| C．Cover nearly 250 meters | D．Have to pay some money. |
