1 . The African elephant holds the record for sleeping the least among mammals — about two hours a day — but now, the elephant seal is giving its namespace a run for its money. Recent experiments on elephant seals showed the animals averaged only two hours of sleep per day during the seven months out of the year they spent at sea.
Jessie Kendall-Bar, a Ph. D. at the University of California, discovered elephant seals’ special ability. She found in the open ocean, elephant seals sleep less than two hours per day. While on land, they sleep more than 10 hours a day. “That’s really special,” she says. Previous observations had shown that elephant seals in the open ocean surface for a couple of minutes at a time. So scientists knew that they must be sleeping underwater. But they knew very little about it.
To find out more, Kendall-Bar developed a headcap to gather data about the animals’ brain waves, heart rates, dive (潜水) depths, and movements to determine when they were sleeping. She discovered that seals do not sleep in two-hour bursts. Instead, they take some “catnaps (小睡)” lasting less than 20 minutes each. Starting at the surface, adult seals take 10-minute dives at great depths, usually from 300 to 1,000 feet.
At this point, the animals enter the first stage of sleep, or slow-wave sleep. Then, they fall into REM sleep, when their bodies turn upside down. It seems REM sleep at great depths is risky because of the inability to escape at that moment. “It is just scary to imagine an animal doing this underwater in that state,” says study co-author Terrie Williams.
But what’s likely happening is that the seals are sleeping at great depths where their primary hunters — sharks and killer whales — hardly appear. “The elephant seal is basically using its ability to div e really deep as a protective mechanism (机制),” says Kendall-Bar. “It doesn’t have to keep one eye open or stay awake. It’s sleeping with its entire brain.”
1. Why does the author start the text with the African elephant?| A．To point out the sleep problems of animals. |
| B．To introduce elephant seals’ sleeping patterns. |
| C．To praise elephant seals’ great ability to survive. |
| D．To stress the importance of getting enough sleep. |
| A．Their sleep habits vary by location. |
| B．They spend a long time playing in the sea. |
| C．They can enter a stage of deep sleep quickly. |
| D．Their brain waves are slower than other large animals’. |
| A．It’s a common group activity. | B．It can increase their heart rates. |
| C．It’s made up of a series of short sleep. | D．It helps them develop their swimming ability. |
| A．To get sufficient food easily. | B．To escape from loud noises. |
| C．To maintain their body temperature. | D．To avoid attack from natural enemies. |
2 . Cows produce much methane, the world’s second worst greenhouse gas, as they breakdown the grass. They are a large source of the greenhouse gases that are driving climate change. Now scientists have shown the pollution from cows can be reduced by adding a little seaweed (海藻) to their food.
Recently, the researchers from the University of California studied 21 cows on a farm for about five months. They taught the cows to get their food from inside a special hood, which allowed the scientists to know the amount of the methane the cows were giving off. They added a small amount of seaweed to the cows’ food.
The consequences were surprisingly good. In some cases, the cows produced 82% less methane. The improvement depended on the kind of food the cows were given. Even the worst-polluting cows produced 33%less methane. Over the five months, the scientists didn’t see any signs that the cows’ stomachs were getting used to the seaweed and starting to produce more methane again. What’s more, the cows that were fed seaweed gained just as much weight as the other cows.
But there are still some big problems with the idea of feeding cows seaweed. For one thing, there’s not adequate seaweed to feed all of the cows in the world. So farmers would have to figure out a way to grow lots of seaweed. A bigger problem is that for most of their lives, cows live in the fields, where they eat grass. That means there’s no chance to feed them seaweed every day.
Still, as the study shows, something as simple as feeding cows seaweed can help reduce some of the pollution causing the climate crisis.
1. Why did the researchers carry out the study?| A．To discover healthier grass for cows. | B．To improve the cows’ living conditions. |
| C．To test the effects of the seaweed. | D．To measure the amount of methane in the world. |
| A．The results of the study. | B．The methods of the experiment. |
| C．The background of the subject. | D．The process of the research. |
| A．Lacking. | B．Enough. | C．Common. | D．Special. |
| A．Critical. | B．Doubtful. | C．Positive. | D．Negative. |
3 . Despite the difficulties, the California coastal ecosystem is improving, largely thanks to the huge appetite sea otters (海獭) have for crabs. In a creative study, scientists revealed the return of otters to their former habitat in a Central California river mouth has slowed the decrease of the area’s river banks by up to 90%. “It would cost tens of millions of dollars for humans to rebuild these stream banks and restore these rivers. The otters are stabilizing them for free, in exchange for an all-you-can-eat crab feast,” said biology professor Brian Silliman, Ph. D. at Duke University.
Like many California river mouths, Elkhorn once was a habitat for otters, which need to eat around 20 to 25 pounds of food every day, with crabs being one of their favorite meals. But after fur traders hunted the local otter population nearly to extinction, the number of crabs exploded over the next century. Crabs dig into salt river soil, and over time can cause a salt river to wear away and collapse. Today, years after the otters returned, rivers and stream banks became more stable.
Angelini, one of the study’s authors, said that tool is an encouraging sign for her team as they face similar threats to Florida’s coastlines from sea level rise, storms, and extra nutrients overflowing into coastal waters. “All these seem unsurmountable,” Angelini said. “However, this study shows that, if we truly understand the ecosystem and know what tools to use, we can see significant benefits to the health and stability of these systems.”
The research team conducted large-scale surveys across 13 tidal (潮汐的) streams, as well as small-scale field experiments at five locations around the river mouth over a six-year period. Otters were not included in some lest sites but allowed to be used in others, using a caging system designed by Angelini.
“And all these years later, we now see these amazing results. It’s an inspiring story about the benefits of conservation and persistent, long-term research,” Angelini said.
1. What does Brian Silliman think of the function of sea otters?| A．It’s complex. | B．It’s expensive. |
| C．It’s effective. | D．It’s inefficient. |
| A．The collapse of salt rivers. |
| B．The hunting for their fur. |
| C．The decrease of the sea crabs. |
| D．The pollution of their habitat. |
| A．Hard to understand. | B．Difficult to deal with. |
| C．Impossible to avoid. | D．Dangerous to settle. |
| A．The process of the research. |
| B．The purpose of the research. |
| C．The limitation of the research. |
| D．The discovery of the research. |
4 . Though you may not know it, about half a billion people worldwide depend on the ecosystems created and supported by corals. And with climate change threatening their survival, marine scientist Enric Sala had an idea that might have seemed impossible.
“We wanted to get into a time machine, go back hundreds of years and actually see a coral reef like they used to be everywhere, before we started exploiting (开发) them, polluting them and killing them all over the world,” Sala said.
The idea was, in essence, made possible during an expedition that Sala led in 2009. The team traveled to a corner of the South Pacific Ocean, and found some untouched reefs.
His team presented their findings to officials in the island country of Kiribati. Then the Kiribati government took steps to protect the waters from fishing and other human activities, but between 2015 and 2016, record levels of ocean warming killed half the coral reefs the team had found.
After hearing that news, they lost hope for the health of coral reefs. But the study continued, and last year, they went in for another dive. Despite the reported conditions, Sala and his team found that the reefs had somehow restored themselves, filled with life and color once more. This resurrection (复兴) is something that Sala says can be traced to two key factors.
The first is, thankfully, half of the corals had not died, as was previously thought. Despite the rise in temperatures, there were enough surviving corals left behind to help reproduce the reefs.
The second factor is the Kiribati government’s decision to fully protect those waters. “There are abundant fish species. They eat all the algae that would smother (窒息) the corals, making it possible for the corals to come back,” Sala explained.
“So if some countries want a future for the fisheries, they need to manage their fisheries in a more responsible way around areas that are set aside to help regenerate the rest of the ocean,” Sala said.
For him and his team, the rebirth of the coral reefs in Kiribati is a beacon of hope among so much pessimism (悲观主义) surrounding the future of reefs.
1. What did Enric Sala want to do according to his words in paragraph 2?| A．Study some untouched coral reefs. | B．Develop technology for time travel. |
| C．Raise awareness about sea protection. | D．Restore coral reefs to their original state. |
| A．Habitat destruction. | B．Climate change. |
| C．Water pollution. | D．Biodiversity loss. |
| A．Fall of ocean temperature. | B．Introduction of new fish species. |
| C．Official funding for restoration efforts. | D．Sufficient surviving corals for reproduction. |
| A．Killing all the algae in the ocean. | B．Reducing dependence on fisheries. |
| C．Protecting the ocean from overfishing. | D．Strengthening cooperation with scientists. |
5 . Researchers recently discovered that mosquitoes who have their sleep interrupted would rather get rest than go looking for their next meal. “It was a bit surprising. Sleep deprived (睡眠不足) or not, a blood meal should appeal to them,” said Oluwaseun Ajayi, the leader of the study.
To study mosquitoes, researchers spent more than a year developing ways to analyze how they sleep, and to show the posture of mosquitoes accurately and count their amount of sleep. It was particularly challenging because of something researchers call the “observer effect”. This is when the act of just observing something can change its outcome. In the case of mosquitoes, they’re able to sense that people are nearby due to their body heat, movement, smells and breath. To deal with those circumstances, researchers set up the experiment in a quiet lab where the mosquitoes were several rooms away from anybody who might pass by. They placed cameras and infrared sensors (红外传感器) in the room so they could record whenever the mosquitoes moved without any risk of disturbing them.
Researchers found that the mosquitoes in the lab slept between 16 and 19 hours each day. When mosquitoes were actually in a sleep-like state, their hind legs are lowered, and they bring in their bodies closer to the surface where they are resting. Then, researchers moved their sound equipment regularly at night or during the day to subject them to sleep deprivation. More than three-quarters of the mosquitoes that got to sleep normally went hunting for a blood meal when they were awake. But less than one-quarter wanted to eat after a sleepless night.
Mosquitoes can spread serious diseases to humans. By understanding the sleep rhythms of insects, researchers hope to find new methods to prevent the spread of infections. “In fruit flies, a link between sleep and immunity (免疫力) has been established. And immunity is an important factor for disease transmission in mosquitoes,” Ajayi says. “Based on this, this research would provide us with an understanding of the role of sleep on the disease transmission in mosquitoes.”
1. What did the researchers recently find?| A．The regular sleep patterns of mosquitoes. |
| B．An effective way to prevent mosquito bites. |
| C．The lack of sleep increases the death of mosquitoes. |
| D．Sleep deprivation influences mosquitoes’ eating behaviors. |
| A．Interrupting the sleep of mosquitoes. | B．Avoiding the impacts of observers’ act. |
| C．Figuring out the number of mosquitoes. | D．Placing suitable equipment in the laboratory. |
| A．The results of the experiment. | B．The process of the experiment. |
| C．The purpose of the experiment. | D．The significance of the experiment. |
| A．Conduct research on sleep rhythms of humans. | B．Explore new means of improving human sleep. |
| C．Help reduce the diseases spread by mosquitoes. | D．Present the relationship between sleep and immunity. |
6 . If you’re new to San Francisco, paying the city a visit, or simply looking for a new playground for you and your dog, here are four of the finest dog parks in San Francisco.
Corona Heights Dog Park
Often visited by residents from all over the city because of its nearness to the Randall Museum, Corona Heights Dog Park offers pets and owners breathtaking view after a steep hillside climb, and a fenced dog area that allows dogs to let loose without a leash (狗链). Owners will also enjoy the playground, tennis courts and basketball courts.
Dolores Dog Park
The grounds of Dolores Park once served as camps for those who were left homeless by the 1906 earthquake, but now are often visited by crowds of Mission District people. Four-legged friends can also wander about care free off-leash while making friends with other members of the doggie community.
Pine Lake Dog Park
Famous for its place as a rest stop for hundreds of species of birds to fly to and from warmer climates, Pine Lake Park is also prized by city dogs and their owners for their nice hiking paths, picturesque lake suited for swimming, and off-leash area on the park’s west end that lets dogs run free.
Buena Vista Dog Park
With a history of 146 years, Buena Vista Park is San Francisco’s oldest park. Dogs and owners with plus energy will love burning it on this park’s steep paths and winding staircases. Dog owners should have good control over their dogs, as it’s quite easy for dogs to get separated when going through Buena Vista’s many twists and turns.
1. What do Corona Heights Dog Park and Dolores Dog Park have in common?| A．There are many steep stairs there. | B．Dogs can go around freely there. |
| C．They serve as camps for the homeless. | D．It is suitable for hiking for owners of dog. |
| A．It is a good place for all kinds of birds to rest. | B．It is close to a museum. |
| C．Dogs must be on a leash there. | D．It is suitable for making friends. |
| A．Dolores Dog Park. | B．Pine Lake Dog Park. |
| C．Buena Vista Dog Park. | D．Corona Heights Dog Park. |
7 . Bumblebees are vanishing at a rate consistent with widespread extinction, and climate change is playing a big role. The analysis comes from a new study published in the journal Science today.
The authors found that the likelihood of a bumblebee population surviving in any given place within North America and Europe has dropped by an average of 30 percent as temperatures have risen.
Pesticides, habitat loss, and pathogens(病原体) have already hit bumblebee populations hard. The new study, however, is able to isolate the effect that hotter temperatures are having on bumblebees. Sadly, bees are having a hard time adapting to a warming world. “If things continue along the path without any change, then we can really quickly start to see a lot of these species being lost forever,” lead author of the study Peter Soroye tells The Verge.
That’s not just a tragedy for the bees. It’s also bad news for all the plants that they pollinate and for humans who eat the fruits (and vegetables) of their labor. “We also lose out on a lot of color on our plates,” Soroye says. “Tomatoes, squash, and berries are just some of the crops we can thank bees for pollinating. Animal pollinators like bees, birds, and butterflies could be responsible for up to 1 out of every 3 bites of food we eat,” the US Department of Agriculture says.
For this study, Soroye and colleagues examined data from 1900 to 2015 on 66 species of bumblebees across North America and Europe. They mapped the places bees called home and how their distribution changed over time. They found that bees were vanishing in the areas that had heated up beyond the limit in which the bumblebees had historically been able to survive.
Some bee populations are colonizing new territories that were previously too cold. But those gains are overshadowed by losses in areas where the bees once thrived but are now too hot.
1. What is bumblebees’ main struggle?| A．Habitat loss | B．Climate change | C．Human activities | D．Virus treat |
| A．Humans can barely strive to save bumblebees from extinction. |
| B．Bumblebees will inevitably die out some day. |
| C．Bumblebees serve as a delicacy on our plates. |
| D．Human’s lives are tightly linked to bumblebees’. |
| A．Animal pollinators eat up 1 out of 3 of our food. |
| B．Peter Soroye’s study started from 1900 and lasted 25 years. |
| C．Bumblebees can not be accustomed to the places they used to live in. |
| D．Bumblebees are more used to colder weather. |
| A．The negative effects outweigh the positive ones. | B．No cold areas are left for Bumblebees. |
| C．The losses are beyond estimation. | D．Bumblebees will have a rather bright future. |
8 . Legend has it that centuries ago, manatees (海牛) used to be mistaken for mermaids, so a sight last week at one Florida state park would have put ancient sailors in shock.
Blue Spring State Park is home to one of the largest winter gathering sites for manatees in Florida, and recently, the park reached a new record when the number of manatees spotted in one group was nearly 1,000.
Manatees typically flock to the park during the winter months. According to a Facebook post from the non-profit Save the Manatee Club, January 21 was one of the coldest mornings of the Florida winter season so far. The temperature of the St. Johns River, which Blue Spring sits on, was recorded at 14.9 ℃.
To survive the cold winter weather, manatees will seek out water that is typically warmer than 20 ℃. This is because despite their thick-looking bodies, the blubbery animal affectionately known as the sea cow only has “about an inch of fat and a very slow metabolism (新陈代谢), meaning they cannot easily stay warm,” says the state park.
Since their spring water remains at a constant 22.2 ℃, and is protected from human recreational activity, Blue Spring makes the perfect manatee shelter during the colder months. “What’s more, many manatees rely on artificial warm water sources from power plants, and these might be going off line in the near future. So having some of these manatees come to these natural warm water sites and finding them is really encouraging,” says Cora Berchem, a research associate and the director of multimedia at Save the Manatee Club.
According to the Florida Fish and Wildlife Conservation Commission, there are anywhere between about 7,000 to 11,000 manatees in Florida, which represents a large increase over the past 25 years.
1. What does the underlined phrase “flock to” in Paragraph 3 mean?| A．Escape from. | B．Drop into. | C．Depart from. | D．Flood into. |
| A．It serves as a recreation center. | B．The temperature remains at 22.2 ℃. |
| C．It is a well-preserved state park. | D．Power plants heat the shelter there. |
| A．Importance of protecting manatees. | B．Why manatees’ population grows. |
| C．Unique living habits of manatees. | D．How manatees fight against cold. |
| A．A Club Taking Measures to Rescue Manatees |
| B．A Record Number of Manatees Spotted in Florida |
| C．Florida: the Largest Winter Shelter for Manatees |
| D．Manatees: an Animal Resistant to Cold Weather |
9 . Whether it be a person, an animal, or even an insect, a mother’s instincts (本能) are never wrong. This idea rings true for a mother cat who acted fast and sought out help when her kittens were in trouble. This mother cat’s quick thinking may have just saved her babies.
In the urban district of Izmir in western Turkey, a cat walked into a regular hospital holding a kitten in her mouth. As the mother cat moved through the hospital, people were surprised to see such a sight, but let her pass. The mother cat asked for help, crying for a long time. She was familiar to the hospital staff, who had been leaving her food and water outside, but they were unaware that she had given birth to kittens.
The mother cat was concerned for her young because they weren’t able to open their eyes. After the doctors looked at the kittens, they noticed that they were suffering from eye infections, one of the doctors recalled, “We consulted with vets (兽医) and gave medicine as described. When the kittens opened their eyes a short time later, we were excited.” Later, they were sent to an animal hospital for further care. The cats are now up for adoption and will hopefully find loving forever homes.
When it comes to mother cats and kittens, kittens completely depend on mothers for the first few months of their lives. Because they are blind and almost deaf until about two or three weeks old, the mother cat must protect them from any threat or danger. Without the mother cat’s help, the kittens may not make it to adulthood.
As shown by the mother cat in Turkey, a mother’s love and protection knows no bounds. Whether the mum is a human or a cat, mothers will always look out for their babies and make sure they are safe and healthy.
1. Why did the mother cat show up in the hospital?| A．To beg for food. | B．To get her babies treated. |
| C．To ask the patients for help. | D．To give birth to her babies. |
| A．They built them a home. | B．They adopted all of them. |
| C．They operated on them immediately. | D．They gave them the right medicine. |
| A．Their physical state. | B．Their eating habit. |
| C．Their appearance. | D．Their behavior. |
| A．Cat has nine lives. | B．One good turn deserves another. |
| C．Love makes a difference. | D．Mothers know their kindness only when they raise their children |
10 . Almost all new parents struggle to get enough sleep while caring for their newborns. For some penguin (企鹅) parents, though, periods of sleep are especially short.
Researchers recently found that Chinstrap penguins only sleep for about four seconds at a time in order to protect their eggs and newborn chicks. They do this thousands of times throughout the day. The short “microsleeps” total around 11 hours each day. The microsleeps appear to be enough to keep the parents going for many weeks.
Niels Rattenborg, a sleep researcher at the Max Planck Institute for Biological Intelligence in Germany, said, “What’s surprising is that the penguins are able to function okay and successfully raise their young.”
Chinstrap penguins usually lay their eggs in November in nests made up of small rocks. Mated (交配的) pairs share parenting responsibilities. One parent usually watches the eggs and chicks alone while the other goes off fishing for family meals. Adult penguins don’t face many natural enemies in the mating season. But large birds called brown skuas eat the penguin eggs and small chicks. Other adult penguins may also try to steal the small rocks from the nests, so penguin parents must always be on guard.
For the first time, scientists followed the sleeping behavior of Chinstrap penguins. They did this by attaching devices that measure brain waves. They collected data on 14 adults over 11 days on King George Island off the coast of Antarctica.
Won Young Lee, a biologist at the Korean Polar Research Institute, thought of the idea for the study when he saw mating penguins often blinking (眨) their eyes and possibly sleeping. But the team needed to record brain waves to confirm the animals were sleeping. “For these penguins, microsleeps have some restorative functions,” he said. He added that they would not survive without it.
The researchers didn’t collect sleep data outside the mating season. But they suspect that the penguins may sleep for longer periods at other times of the year.
1. What have researchers found about Chinstrap penguins?| A．They take turns to take care of the young. |
| B．They sleep for several seconds at a time. |
| C．They rest for 11 hours in a row every day. |
| D．They behave poorly due to lack of sleep. |
| A．The habitats of the penguins. | B．The living habits of the penguins. |
| C．The mating seasons of the penguins. | D．The natural enemies of the penguins. |
| A．Microsleeps of the penguins matter in their survival. |
| B．It’s difficult to record brain waves of the penguins. |
| C．The penguins may sleep longer than people believe. |
| D．More funds are needed to further study the penguins. |
| A．A book review. | B．A travel brochure. |
| C．A science journal. | D．A chemistry textbook. |
