A “secretive” new species of frog has been discovered on the forest floor in India’s Western Ghat mountain range. Named the starry dwarf frog after the markings on its dark brown back, it is just 2 centimeters long.
The frog, whose closest relatives are a group of species native to India and Sri Linka, is the only member of an ancient lineage (血统) dating back to millions of years ago, according to researchers from India and the US. It is unclear whether the species is descended (传下来) from African or Asian frogs.
A group of Indian and US researchers first came across the local species hidden in leaf-litter as part of a wider project to look for new frogs, lizards and snakes in the richly biodiverse region and stored it in a jar for later study. Genetic testing and a closer look at its shape, colouring and other features have shown that it doesn’t match any existing species. Kartik Shanker of the Indian Institute of Science, who helped design the study, says while it is common to find new frog in India, this one needs to be noticed. “This particular species not just is a new species, but also belongs to a new genus (属), and that makes it a little more special,” says Shanker.
The number of known species of frog identified in India has climbed from around 200 to above 400 over the past two decades. While many species new to science are frequently sorted as endangered at once, it is too early to say whether the starry dwarf frog is threatened. “They are very secretive,” says Shanker, adding that the team didn’t know the size of its population. The frog is active at night and lives near water.
Habitat loss is a serious risk to frogs in tropical forests around the world, alongside threats such as a deadly fungus (真菌) that has been killing off amphibians (两栖动物) for the past four decades. But the new species was found in a reserved forest, meaning it will enjoy a degree of protection by Indian government agencies.
1. What can we learn from paragraph 3?| A．The species was discovered by tourists. |
| B．The species was found in a rich region. |
| C．The species was further studied. |
| D．The species was finally set free. |
| A．It is in small quantities. | B．It is an endangered species. |
| C．It is well worth attention. | D．It is related to African frogs. |
| A．Habitat loss is the chief threat to frogs. |
| B．The new species may face less dangers. |
| C．Tropical forests in India are all under protection. |
| D．The Indian government determines to save frogs. |
| A．A pet guide. | B．A social website. |
| C．A travel journal. | D．A science report. |
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【推荐1】Dolphins are social and intelligent animals. And, like the way humans maintain relationships by hugging or giving a handshake, dolphins breathe together at the same time when they come up from the water for air. This shared act is important for creating social connections. But sharing the same air and area is also spreading an infectious and deadly disease among the dolphins.
Janet Mann and other scientists are trying to understand the virus. They discovered it in the water off the American states of Virginia and Maryland. It is now spreading to other Atlantic coast dolphins.
Mann explains that the dolphin virus is in the lungs. “When dolphins breathe together at the surface, they’re sharing tiny droplets just like we do when we’re talking with each other,” she said.
During her 35 years of studying dolphins, Janet Mann has noticed that even though dolphins have close friends, they visit other dolphins and leave the groups often. Following the social lives of dolphins in the Chesapeake Bay has permitted researchers to identify over 2,000 dolphin individuals. They can remember them by their special shapes and markings on their back fins.
Two researchers, Melissa Collier and Ann-Marie Jacoby, saw two dolphins. A third dolphin joined his friends. All three dolphins came to the surface of the water and breathed together. “This is typical, male behavior. The males stay pretty coordinated (协调) with each other. The females sync (同步), but not as regularly. They syne mostly with their offspring (幼崽).” Mann says. This behavior pattern might explain why more male dolphins have died in the most recent outbreak of the virus.
Viruses are naturally occurring in the wild, but human activities in the ocean can make the virus worse by wakening environments and populations even more. Pollution from carbon and plastics, limited food sources, along with ocean warming from climate change, harm the animals. These factors weaken the dolphins’ immune systems. “So, they are extremely vulnerable (脆弱的,易受伤的) to virus outbreaks.” Mann says.
1. What are Mann and other scientists trying to do?| A．Record the dolphins’ social habits. | B．Increase the population of dolphins. |
| C．Compare the viruses among dolphins. | D．Study the spread of the virus among dolphins. |
| A．Researchers. | B．Close friends. |
| C．The social lives of dolphins | D．Over 2,000 dolphin individuals. |
| A．They absorbed more air than females. | B．They did more social activities together. |
| C．They came to the surface of the water more | D．They were more vulnerable to viruses. |
| A．Ocean warming. | B．Dolphins breathing together. |
| C．Researchers studying dolphins. | D．The growing population of dolphins. |
【推荐2】Scientists have mapped the largest coral reef (珊瑚礁) off America’s Atlantic coast. Researchers say the reef spreads about 500 kilometers from Florida to South Carolina. At some points, it is 109 kilometers wide. The researchers measured the reef using 3D mapping technology.
Ocean scientists have known since the 1960s that some coral life was present off the Atlantic Coast. But the reef’s exact size had remained unknown. New underwater mapping technology made it possible to create images of the ocean floor in 3D.
The largest yet known deep coral reef “has been right under our noses, waiting to be discovered,” said Derek Sowers. He is an expert at the nonprofit group Ocean Exploration Trust.
The reef was found at ocean depths from 200 to 1,000 meters. Deep-sea life cannot use sunlight to carry out photosynthesis (光合作用). Instead, reef corals at extreme depths must get food particles (颗粒) out of the water for energy.
Deep coral reefs are known to contain animals such as sharks, sea stars, octopus and many kinds of fish.
Unlike deep coral reefs, tropical (热带的) reefs are more familiar to scientists and sea explorers alike because they are easier to reach. The world’s largest tropical coral reef system, Australia’s Great Barrier Reef, spreads for 2,300 kilometers.
Sowers said it is possible larger deep-sea reefs will be discovered in the future since only about 25 percent of the world’s ocean floor has been mapped in 3D. Only 50 percent of U.S. offshore waters have been mapped. Maps of the ocean floor are created using high-technology sound equipment on ships.
Erik Cordes is a sea biologist at Temple University and a co-writer of a study on the mapping operation. He said deep reefs cover more of the ocean floor than tropical reefs. But both are currently facing similar risks, including climate change and damage from exploring oil and gas activities.
1. How do deep-sea corals get the energy to grow?| A．They get it from sunlight. | B．They eat other sea animals. |
| C．They create it by themselves. | D．They get food out of water. |
| A．They are much easier to reach. | B．More advanced technology will be developed. |
| C．Scientists are showing growing interest in them. | D．Most of the ocean floor hasn’t been mapped. |
| A．Differences between the two corals. | B．Human activities harming them. |
| C．The need to study deep-sea corals. | D．The importance of deep-sea corals. |
| A．Scientists Map Largest Deep-Sea Coral Reef Ever | B．Scientists Map Deep-Sea Floor for Further Research |
| C．Deep-Sea Coral Reefs Are Home to Sea Animals | D．A Deep-Sea Secret Comes to Light |
【推荐3】You may have never seen a dodo bird in your lifetime. Driven to extinction on the island of Mauritius in 1692, the species has become a thing of the past. But it could soon be brought back to life.
A company called Colossal Biosciences, which has offices in Austin, plans to “de-extinct” the species alongside some other well-known extinct species, the woolly mammoth (长毛象) and Tasmanian tiger. According to the company, all three will be de-extinct within the next decade.
The dodo bird was a giant flightless pigeon (鸽子) on the island of Mauritius. The island, off the east coast of Africa, was visited by sailors in the early 1600’s. When the sailors arrived there, they would walk around the island and knock the heads of the dodos because there was nothing else to do on the island. By 1692, the species was extinct.
“Bringing back extinct animals isn’t just because we can,” says Forrest Galante, a scientist who serves as a conservation advisor to Colossal Biosciences. “In the case of the dodo, it will put back something of the food chain.” Removing the bird created a gap in the ecosystem of the environment, Recovering it, in theory, should help fill that gap. “You’re bringing back a creature, an individual and a group of them that will most importantly repair a damaged ecosystem, because they’ve been removed by human beings,” says Galante.
Just like in Jurassic Park, DNA is required to bring back an extinct animal. DNA from species like the dodo bird and woolly mammoth can be recovered. According to Galante, this DNA is then hatched into a related species that is living today. In the case of the dodo bird, a pigeon is used. When the pigeon lays eggs, dodo birds will hatch from the eggs.
The new dodos will not be the exact same type of bird, but close enough to fill the gaps their extinction left behind.
1. What does Colossal Biosciences plan to do?| A．Preserve existing endangered animals. | B．Document the history of extinct species. |
| C．Bring back some extinct animal species. | D．Teach people to raise and train dodo birds. |
| A．Lack of food. | B．Human activity. |
| C．Loss of habitat. | D．Coastal natural disasters. |
| A．It is beneficial to the ecosystem. | B．It is a little late to do such a thing. |
| C．It is far beyond humans’ capability. | D．It is unnecessary to save the species. |
| A．The inspiration for collecting DNA. | B．How dodo birds hatch from their eggs. |
| C．The impact of pigeons on dodo birds. | D．The use of DNA for reliving dodo birds. |
【推荐1】This spring, Facebook revealed that it’s developing a version of Instagram for children under 13 years old that gives kids the chance to connect with friends and family without seeing ads or being targeted by child predators(奴役儿童者).
But as any caregiver or parent knows, screens are addictive. Many adults can’t tear themselves away from their smartphones, computers, and televisions. And children are even less prepared to resist the lure. As is reported, kids between the ages of 8 and 12 already spend 1,200 hours a year in front of screens. What’s more, child-protection advocates also worry that Facebook, which owns Instagram, won’t be able to adequately protect young users’ privacy or stop them from cyberbullying.
Erin Wilkey Oh, content director at the nonprofit Common Sense Media, says, “Social media could benefit younger kids if it’s done thoughtfully. But Facebook’s track record shows the company may not really do what it promises. Plus, there are already ways for children to connect with family and friends online. Do they really need another app to make them spend more time on their devices?”
The relationship between kids and social media is more complicated than it seems. A 2020 survey conducted by Common Sense Media found that even though social media use was linked to depression and anxiety, many teens also saw social media as a way to access critical information about their mental and physical health and connect with their peers.
Despite the outcry(强烈抗议), Facebook doesn’t seem to slow its plans to roll out the app. So parents can minimize the potentially negative impacts. Parents can create a set of rules that details how much screen time kids are allowed each week and what they can watch. It’s not perfect, but it can help families balance screen time with exercise, and real-life social interactions that are vital to children’s well-being.
1. What does the underlined word “lure” in Paragraph 2 mean?| A．Suffering. | B．Connection. |
| C．Attraction. | D．Devotion. |
| A．Social media do good to little kids. | B．Apps intended for kids are necessary. |
| C．Facebook often breaks its promise. | D．Facebook doesn’t have to develop its new app. |
| A．Social media do harm to children. |
| B．Many kids benefit from social media in some way. |
| C．Children shouldn’t have access to social media. |
| D．More surveys should be done on social media. |
| A．Keep their kids off Facebook. |
| B．Show their kids real social skills. |
| C．Stress negative influences online. |
| D．Weigh their kids’ workout against online time. |
【推荐2】One of the world’s most significant ecological and environmental problems is desertification. Desertification is a type of land degradation in which a relatively dry land region becomes increasingly arid (干旱的), typically losing its bodies of water as well as vegetation and wildlife. It’s happening all over the world and it’s happening very quickly.
There are several causes of desertification. The immediate cause is the removal of most vegetation. This is driven by a number of factors, such as drought, tillage (耕种) for agriculture, overgrazing (过度放牧) and deforestation for fuel or construction materials. Some farmers farm their land too much, without giving the soil a chance to recover. Others allow their animals to eat up large areas of grass far too quickly — at a rate that makes it impossible for the grass to grow back. Cutting down trees is another major cause of desertification. Trees help protect the soil. Without trees, the soil easily blows away in the wind or washes away in floods. Besides, wildlife plays an important role in the preservation of vegetation and soil. So removal of animals is also one of the main drivers of increasing desertification. Moreover, some parts of the Earth are hotter today than they used to be. This change in climate has dried out a lot of land.
The consequences of desertification can be disastrous. So we need to take steps to prevent desertification. We should pay attention to how much energy we use in our daily lives. That way, we can reduce the amount of carbon dioxide released. We can walk or cycle short distances, and use less water. We can also protect our forests by reusing paper and not using disposable chopsticks. What’s more, we should try to make people around us aware of the problem and encourage them to change their daily habits in the same way. As long as we create a harmonious environment, life on this planet will live in peace and abundance, and stop the pace of desertification together.
1. What can we learn about desertification from paragraph 1?| A．It is happening slowly throughout the world. |
| B．It is an ecological and environmental solution. |
| C．It is the process during which farmland turns into desert. |
| D．It is the process during which a relatively dry land becomes rich. |
| A．Wildlife does harm to the vegetation and soil. |
| B．The change in climate contributes to dried land. |
| C．Animals eat the grass at a slower rate than grass grows. |
| D．Trees are blown away in the wind or washed away in floods. |
| A．Changing our good daily habits. |
| B．Raising people’s environmental awareness. |
| C．Using more paper and less disposable chopsticks. |
| D．Using more energy and releasing less carbon dioxide. |
| A．Desertification — the major cause of climate change. |
| B．Desertification — everyone’s responsibility for its treatment. |
| C．Desertification — the disastrous consequences of deforestation. |
| D．Desertification — the most significant ecological and environmental problem. |
【推荐3】Not being able to fall asleep or stay asleep is not a disorder in itself but a sign of some other problems, often a physical one.
If you have trouble sleeping, the American Sleep Disorders Association suggests that, for a week or two, you put down the time you go to bed, get up, exercise, and drink coffee, tea or wine. The purpose is to find the habits that may affect your sleep.
Then: a. Don't drink coffee in the six hours before going to bed.
b. Stop smoking and drinking at bedtime.
c. Don't sleep during the day.
d. Go to bed at the same time every night. Set your alarm clock for the same time every morning and get up at that time, whether or not you sleep well.
e. Use the bedroom only for sleep. Read, watch TV, eat and talk elsewhere.
f. Take sleeping pills according to your doctor's directions and don't take them for longer than three weeks at a time.
g. If you haven't fallen asleep within 15 minutes of going to bed, don't turn over worrying about it. Get up and read or watch TV until you are sleepy, then return to bed.
If you continue to have trouble sleeping, ask your doctor for help or go to a sleep-disorders center.
1. According to the passage, there is probably ________ if you are not able to fall asleep or stay asleep.| A．a bad way of sleeping |
| B．a disorder in sleep |
| C．a physical reason |
| D．a problem caused by the brain |
| A．ask a doctor for help or go to a sleep-disorders center |
| B．put down the time you do things every day |
| C．do more physical exercise |
| D．find out the cause first |
| A．Taking some sleeping pills every day. |
| B．Reading books before you go to bed. |
| C．Setting your alarm clock at night. |
| D．Forming good living habits. |
| A．tell us not being able to fall asleep is a serious disease |
| B．provide us with some suggestions on the sleep problem |
| C．persuade us not to go to see the doctors when we are ill |
| D．help the American Sleep Disorders Association to find the causes of not being able to fall sleep |
