In films and TV shows, police investigators dust crime scenes for fingerprints to catch criminals. Now, conservationists (环保主义者) are using a similar method to tackle the illegal overfishing of sharks and rays.
Overfishing is when too many of a particular type of fish are caught, putting that species in danger. Many sharks and rays are killed because of a high demand-and a high price-for their fins(鱼鳍). In some countries, the fins are used as an ingredient in shark fin soup, which some people believe can cure certain illnesses.
About 100 species of sharks and rays are protected by the Convention on International Trade in Endangered Species of Wild Fauna and Flora(CITES), an agreement between 184 countries to limit sales of wildlife that may be at the risk of dying out. CITES has teams of people who visit ports and fish factories to look for evidence of protected species being illegally caught and sold. The idea is to punish those responsible and stop it from happening, but finding evidence is difficult. If a fish is already cut up and ready for sale, it’s hard to tell which species it was. Often, fish are sold before inspectors arrive.
Scientists have come up with a process that analyzes “fish dust”-tiny traces of fish that get left on the floor at ports and factories, even after the fish are no longer there. Using a process called metabarcoding(宏条形码技术), they examine the chemical that carries all the information about a living thing’s body and characteristics in the dust and can tell if it is from a protected species.
The scientists tested the method in Indonesia, where many sharks and rays are caught and sold. They studied dust from seven sites and found evidence of 61 species of sharks and rays. More than 80% of them were CITES-protected species. Dr. Andhika Prasetyo, the scientist who led the research, hopes the new method will be helpful in protecting endangered sea life.
1. Why is dusting crime scenes mentioned in paragraph 1?| A．To discuss overfishing in a broader context. |
| B．To introduce the initial purpose of the passage. |
| C．To bring forth something new with the familiar. |
| D．To show the difference between two professions. |
| A．The risk in saving wildlife and the opportunity to seize. |
| B．The mission of CITES and the trouble inspectors confront. |
| C．The number of endangered species and the way to save them. |
| D．The agreement made by countries and the responsibility each carries. |
| A．It scans the body of a fish to confirm its killer. |
| B．It guides the investigators to the remains of a fish. |
| C．It turns a fish into the dust and test its characteristics. |
| D．It identifies a fish by studying the chemical in the dust. |
| A．The evidence collected belong to over 61 species. |
| B．Scientists in Indonesia will carry out further studies |
| C．The dusting method is promising in protecting sea life. |
| D．More than 80% of sharks and rays have been in danger. |
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【推荐1】There was great excitement on the planet of Venus( 金 星 ) this week. For the first time Venusian scientists managed to land a satellite on the planet Earth, and it has been sending back signals as well as photographs.
The satellite was directed into an area known as Manhattan. Because of excellent weather conditions and extremely strong signals, Venusian scientists were able to get valuable information about the possibility of a manned flying saucer( 飞碟) landing on Earth. A press conference was held at the Venus Institute of Technology.
"We have come to the conclusion, based on last week’s satellite landing, "Prof. Zog said, that there is no life on Earth. "
“How do you know this?" the science reporter of the Venus Evening News asked.
"For one thing, Earth’s surface in the area of Manhattan is composed of solid concrete and nothing can grow there. For another, the atmosphere is filled with carbon monoxide and other deadly gases and nobody could possibly breathe this air and survive.”
“Are there any other sources of danger that you have discovered in your studies?”
“Take a look at this photo. You see this dark black cloud staying over the surface of Earth? We don' t know what it is made of, but it could give us a lot of trouble and we shall have to make further tests before we send a Venus Being there.”
"Over here you will notice what seems to be a river, but the satellite findings indicate it is polluted and the water is unfit to drink.”
“Sir, what are all those tiny black spots on the photographs?”
“We’re not certain. They seem to be metal particles that move along certain paths. They give gases, make noise and keep crashing into each other.”
“Prof. Zog, why are we spending billions and billions of Zilches to land a flying saucer on Earth when there is no life there?"
“Because if we Venusians can learn to breathe in the Earth atmosphere, then we can live anywhere.”
1. What tone did the author use when writing the text?| A．Serious | B．Aggressive | C．Humorous | D．Frustrating |
| A．Over population. | B．Global warming. | C．Damaged forests. | D．Heavy traffic |
| A．To tell us a dream of Venusian scientists. |
| B．To discover the secret of life on other planets. |
| C．To persuade people to try living on the earth. |
| D．To remind people on the earth of some crises.(危机). |
【推荐2】Every day, thousands of rangers patrol national parks and other protected areas in Africa. Their job is fraught with danger, both from hostile humans armed with automatic weapons and from the unappreciative and potentially aggressive wildlife, armed with tusks, teeth and claws, which they are helping to preserve.
That is particularly true of data on poaching (偷猎), which remains, in both senses of the word, an elephantine problem. Since 2006 African elephant populations have declined by around 30%. In 2021, according to Monitoring the Illegal Killing of Elephants (MIKE), a conservation programme, around 40% of elephant deaths were a result of poaching.
Elsewhere, there is great variation in the pressure on animals like elephants. Some parks, like Garamba in the Democratic Republic of Congo (DRC), are badly hit — with more than 90% of the bodies found by rangers being victims of poachers.
Natural variables such as habitat type, they discovered, make little difference.
One factor that was unquantifiable, and therefore untestable, according to Dr Kuiper, was local political will to preserve wildlife. But this study does nevertheless confirm observations made elsewhere, that the best form of conservation is a prosperous population.
| A．Human ones predominate. |
| B．The severity of elephant poaching varies from place to place. |
| C．Humans are the biggest factor defining elephant ranges across Africa. |
| D．There was one unexpected result, though — the impact of armed conflict. |
| E．But their work is important, not least because the data they collect are crucial to conservation planning. |
| F．In others, like Chobe, in Botswana, less than 10% of dead elephants discovered have been killed illegally. |
| G．Current discussion of how to reduce poaching focuses on two areas: reducing demand and reducing supply. |
【推荐3】The idea that humans are facing a global extinction of experience of nature is popular, but is it true? To give more light on this issue, the scientists measured how the average distance from an individual’s home to the nearest area with low human impact changed in the last decade.
The scientists found that humans currently live 9.7 kilometers away from a natural area on average, which is 7% further away than in the year 2000. Europe and East Asia have the highest average distance to natural areas, such as 22 kilometers in Germany and 16 kilometers in France. The scientists also showed that tree cover within cities has declined worldwide since 2000, suggesting that the possibility for the urban population to access green spaces is reducing as well.
The scientists also systematically searched for scientific publications assessing a trend in experiences of nature, finding that the number of studies assessing these trends was very low (the number is 18), most of which are about the US, Europe and Japan. This shows that more studies should investigate the claim about the extinction of nature experience, especially in Africa and Latin America. The 18 studies found by the scientists show a decline in visits to nature parks in the US and Japan, a decrease in camping activities in the US, and a decrease in the number of flower species observed by Japanese children. They also find signs of decline in the use of natural elements in novels, songs and cartoons.
Despite these examples of decline, other interactions are increasing. Watching wildlife documentaries or interacting with wild animals in videogames is, for example, more common than a few years ago. “New ways of digitally interacting with nature have certainly emerged or increased in recent years,” says Dr Gladys Barragan-Jason. “But several former studies show that these vicarious interactions have a lesser effect on our sense of connection with nature than exposure to nature, such as visiting nature parks.”
1. How does the author mainly develop the text?| A．By giving examples and making contrast. |
| B．By listing data and classifying them. |
| C．By giving examples and definitions. |
| D．By analyzing data and making comparison. |
| A．the distance between humans and nature |
| B．the connection between humans and wild animals |
| C．reading novels, singing songs and watching cartoons |
| D．tree cover, visits to nature parks and nature presence in the arts |
| A．Positive. | B．Novel. | C．Indirect. | D．Complex. |
| A．Global Extinction of Green Spaces. | B．Decline in Experiences of Nature. |
| C．The Lost Joy in the Natural World. | D．A New Way of Connecting With Nature. |
【推荐1】Sound may offer a creative way to take the ocean's temperature. Climate change is steadily warming the seas, which have absorbed about 90 percent of the excess heat trapped by greenhouse gases. This warming contributes to sea-level rise, endangers species and influences weather patterns.
But tracking the warming is tricky. Ship-based observations capture only snapshots in time over a tiny portion of the water. Satellite observations cannot enter very deep below the surface. The most detailed picture of ocean heat comes from Argo, which can drop down to around 6,500feet. But there are only about 4,000 such floats, and they cannot sample deeper parts of the oceans.
In Science, researchers at the California Institute of Technology and the Chinese Academy of Sciences compared the travel speeds of sounds produced by undersea earthquakes to detect ocean warming over wider areas. Because sound travels faster in warmer water, differences in speed can reveal changing temperatures. "They're opening up a whole new area of study," says Princeton University geophysicist Frederik Simons, who was not involved in the research.
Inspired by those early efforts to measure ocean heat with sound, Caltech researcher Wenbo Wu thought to monitor low-frequency sound waves sent out by earthquakes below the seafloor. “I know these earthquakes are very powerful sources, "Wu says, "So why not try to use the earthquakes?"”
He and his team tested the idea near Indonesia’s island of Nias, where the IndoAustralian Plate is bumping under the Sunda Plate. The researchers gathered sound data from 4,272 earthquakes of magnitude 3 or greater from 2004 to 2016, and they compared sound wave speeds from quakes that originated in the same spot over the years. By modeling the differences, often just fractions of a second, they found that the ocean near Nias was warming by about 0.08 degree Fahrenheit per decade—more than the 0.047 degree F suggested by Argo’s data. Less than one degree F does not sound large, but it takes considerable heat to warm the entire eastern Indian Ocean.
The new method is promising, says University of Hawaii oceanographer Bruce Howe, who was not involved in the work. Meanwhile Simons and his colleagues are exploring an alternative technique, employing dozens of underwater microphones called hydrophones to catch more earthquake sounds. He notes that finding out the floats’ precise locations will be challenging, however. Overcoming such challenges would fill in important gaps, Wu says, “We really need different methods of gathering the data as much as possible.”
1. What do people do to take ocean’s temperature?| A．Ships sail across all the oceans to take photos. |
| B．Satellites are used to provide data on ocean heat. |
| C．Argo enters the deepest seas for detailed pictures. |
| D．The numbers of floats hit a record high for samples. |
| A．Because its speed varies with the temperature of water. |
| B．Because it accompanies earthquakes below the seafloor. |
| C．Because it is approved by Chinese and US researchers. |
| D．Because its value has been proved by previous efforts. |
| A．They use hydrophones as floats. |
| B．They exchange their data with Argo. |
| C．They meet the same trouble at work. |
| D．They employ new research methods. |
| A．Undersea earthquakes | B．Climate and seas |
| C．Sound and ocean heat | D．New method found |
【推荐2】If your in-box is currently reporting unread messages in the hundreds or thousands, you might have a hard time believing the news: e-mail is on the decline.
At first thought, that might seem to be the case. The incoming generation, after all, doesn’t do e-mail. Oh, they might have an account. They use it only as we would use a fax machine: as a means to communicate with old-school folks like their parents or to fulfill the sign-up requirements of Web sites. They rarely check it, though.
Today’s instant electronic memos—such as texting and Facebook and Twitter messages—are more direct, more concentrated, more efficient. They go without the salutation (称呼语) and the signoff (签收); we already know the “to” and “from”. Many corporations are moving to messaging networks for exactly that reason: more signals, less noise and less time. This trend is further evidence that store-and-forward systems such as e-mail and voicemail are outdated. Instead of my leaving you a lengthy message that you pick up later, I can now send you an easily-read message that you can read—and respond to—on the go.
The coming of the mobile era is responsible for the decline of e-mail. Instant messages bring great convenience to people. They can deal with them at about any time: before a movie, in a taxi, waiting for lunch. And because these notes are very brief, they’re a natural for smart phone typing.
Does this mean e-mail is on its way to the dustbin of digital history? Not necessarily. E-mail still has certain advantages. On the other hand, tweets and texts feel ephemeral—you read them, then they’re gone, into an endless string, but e-mail still feels like something you have and that you can file, search and return to later. It’s easy to imagine that it will continue to feel more appropriate for formal communications: agreements, important news, longer explanations.
So, e-mail won’t go away completely. Remember, we’ve been through a transition like this not so long ago: when e-mail was on the rise, people said that postal mail was dead. That’s not how it works. Postal mail found its smaller niche, and so will e-mail. Technology rarely replaces an institution completely; it just adds new alternatives.
1. What would the incoming generation like to do with their e-mail accounts?| A．Contact close friends | B．Send long messages |
| C．Fill in some forms | D．Communicate with their colleagues |
| A．illustrate the preferences of the young generation |
| B．explain the possible reasons behind the decline of e-mail |
| C．reveal the rapid development of e-communication channels |
| D．offer evidence about the uncertain future of easily-consumed messages |
| A．Conveniently-sent | B．Randomly-written | C．Hardly readable | D．Short-lived |
| A．It’s too early to determine the decline of e-mail. | B．E-mail has reasons to exist on its own advantages. |
| C．E-mail, just like postal mail has come to its end. | D．We should feel sorry for the decline of e-mail. |
【推荐3】Think about a remote control. Something so simple in function is seemingly capable of invisible magic to most of us. Only few have any real idea of why a remote control works. The rest of us just assume it should. And the longer a given technology exits, the more we take it for granted.
Consider for a moment a screen showing modern remote control users versus the first remote control users： the original users would be carefully aiming the remote directly at the television, reading the names of the buttons, and intentionally pressing the button. The modern users would be leaning on a sofa, pointing the remote any which way, and instinctively feeling for the button they desired.
Humans are known for being handy with tools, so it is no surprise that we get so comfortable with our technology. However, as we become increasingly comfortable with how to use new technologies, rather than being humbled by is originality, we consumers often become unfairly demanding of what our technology should do for us Once wonderful new inventions （such as televisions） quickly became commonplace. The focus of consumer attitudes towards them changed from gratitude with respect to discriminating preference. Televisions needed to be bigger and have a higher resolution. Video games needed to be more realistic. Computers needed to be more powerful yet smaller in size.
For children of the last twenty years born into this modern life, these technological wonders seem like elements of the periodic （周期的） table： a given aspect that is simply part of the universe. Younger generations don't even try to imagine life without modern conveniences. They do not appreciate the unprecedented （史无前例的） technology that is in their possession； rather, they complain about the ways in which it fails to live up to ideal expectations. "My digital video recorder at home doesn't allow me to program it from my computer at work. "
If it sounds as though were never satisfied, we aren't. Of course our complaints do actually motivate engineers to continually refine their products. After all, the expectation is that someone, somewhere is working on how to make the existing product even better.
1. What can we infer from paragraph 2？| A．Modern remote controls have no button and instructions. |
| B．Consumers' behavior towards new technologies changes over time. |
| C．Remote controls have become far more effective over the years. |
| D．Modern remote controls are designed more user﹣friendly. |
| A．Less realistic video games. |
| B．Wanting to make sacrifices. |
| C．Needing to understand technology. |
| D．More powerful smartphones. |
| A．The inspiration of modern technology comes from chemistry. |
| B．Younger generation loam technology while they learn chemistry. |
| C．Children naturally take modern technology for granted. |
| D．Children regard many technological inventions as remarkable. |
| A．blessing |
| B．approving |
| C．satisfied |
| D．critical |
【推荐1】The commonly held view is that people arrived in North America from Asia via a land bridge once connecting the two continents. But recent discoveries have suggested humans might have been there earlier. Researchers studying fossilized (化石的) human footprints in New Mexico say that humans were there at least 23,000 years ago.
Matthew Bennett, a specialist in ancient footprints and author of a study on the new findings published in Science, and his colleagues studied 61 footprints by radiocarbon (放射性碳) dating layers of aquatic (水生的) plant seeds preserved above and below the footprints and correctly dated they were made 21,000 to 23,000 years ago. The people who made the footprints were living there in the last Ice Age when two huge ice sheets covering the continent and cold temperatures would have made a journey between Asia and Alaska impossible, indicating humans must have been there much earlier than previously thought.
According to their analysis of the footprints, they were likely made in soft ground at the edge of a wetland by children who were sent to do the work like fetching and catching by adults. Wind probably blew dust over the surface, accumulating (积累) in the prints, thus, leaving footprints that previously recorded.
Their finding also makes it possible to explore the older and more controversial (有争议的) sites with a different light. One such site is Chiquihuite Cave in central Mexico, where stone tools dating back to 30,000 years ago have been found.
David Rachal, an uninvolved but experienced geoarchaeologist (地质考古学家) thought the footprint dates provided by Bennett and his team looked "solid", with seeds providing very reliable and exact ages through radiocarbon dating. "You could not ask for a better setup," said Rachal. However, he was puzzled that no artifacts, such as stone tools, had been found in the area. He thought it was just a theme that would inspire others to explore further.
1. What is the most important evidence dating the time in the passage?| A．The aquatic plant seeds. | B．The fossilized human footprints. |
| C．The stone tools. | D．The huge ice sheets. |
| A．To introduce a historical site. | B．To show the significance of the footprints. |
| C．To compare geoarchaeological discoveries. | D．To explain the course of making a discovery. |
| A．Unconcerned and uncertain. | B．Doubtful and dissatisfied. |
| C．Negative but curious. | D．Favorable but confused. |
| A．The discovery of human footprints. | B．Scientific methods of dating footprints. |
| C．The earlier arrival of people in North America. | D．A discussion on human history among researchers. |
【推荐2】The start-up that attracted the largest investment in the history of cybersecurity, of more than half a billion dollars, has a simple goal: a passwordless future.
Despite the spread of password management software that can generate and remember complicated strings of random characters, some of the most common passwords are still “12345”, “password” and “iloveyou”. As a result, more than 80 percent of hacks involve these kinds of passwords; and passwords remain the most sought-after data by hackers, above other personal or sensitive information.
In many cases, individuals are tricked into handing over password details by phishing emails and other social engineering techniques. Hackers have sought to break into apps and steal entire password databases as well. Passwords are also under attack from new technology, such as automated programs that can rapidly try to guess them, or can try stolen passwords on multiple online accounts.
Since the need to replace the easily forgotten and highly hackable strings of letters and numbers that we use to access everyday life has become even more urgent, the race to replace the password is under way, with biometric-based (基于生物识别的) security emerging as one of the most sought-after solutions. According to Tieo, a union of more than 250 companies, which promotes a standard system of passwordless authentication (身份验证), the vast majority of consumer services will offer passwordless login systems in the next couple of years. “If done correctly and safely, biometrics are really helping us move to a passwordless future in a rapid manner,” said Andrew Jenkinson, CEO of Tieo.
But there are still risks associated with the use of biometric authentication. Unlike passwords, biometrics cannot be changed. This means such data must be closely guarded for privacy purposes and to prevent spoofing—hackers trying to trick cameras or sensors with photos, or masks of their victim. “Biometric authentication and passwordless authentication has its own attack surface,” said Paul Smith, director of security research at CyberPek. His team revealed that it had found a design problem which would allow potential attackers to bypass facial recognition login by injecting a spoofed photo of a user’s face into the process.
The biggest obstacle standing in the way of the start-ups hoping to kill the password is how to change years of habit. Eric Brown, founder of TAK Cyber, a cyber research and advisory company, argued that while sensitive applications may rapidly shift from passwords, other websites have less motivation to update their systems. “You’ll never get rid of them,” he said. “We’re never going to get to the post-password era.”
1. What is the third paragraph mainly about?| A．Why passwords are the most sought-after data. |
| B．How passwords are stolen by phishing emails. |
| C．How passwords have caused us trouble. |
| D．Why passwords are difficult to secure. |
| A．Facial recognition login is the key to fighting hackers. |
| B．Biometric authentication has its own set of problems. |
| C．TAK Cyber’s login system guarantees the safety of data. |
| D．Spoofing brings more problems than automated programs. |
| A．Indifferent. | B．Passionate. | C．Pessimistic. | D．Objective. |
| A．Biometric authentication: password security solution! |
| B．Start-ups race to welcome a passwordless future |
| C．The argument to end passwords has begun |
| D．Killing the password: a cure or a fantasy? |
【推荐3】Today’s artificial intelligence may not be that clever, but it just got much quicker in understanding. A learning program designed by three researchers can now recognize and draw handwritten characters after seeing them only a few times, just as a human can. And the program can do it so well that people can’t tell the difference.
The findings, published in the journal Science, represent a major step forward in developing more powerful computer programs that learn in the ways that humans do.
Although computers are excellent at storing and processing data, they’re less-than-stellar students. Your average 3-year-olds could pick up basic concepts faster than the most advanced program.
In short, “You can generalize,” said coauthor Joshua Tenenbaum. But there’s something else humans can do with just a little exposure—they can break an object down into its key parts and dream up something new. “To scientists like me who study the mind, the gap between machine-learning and human-learning capacities remains vast,” Tenenbaum said. “We want to close that gap, and that’s our long-term goal.”
Now, Tenenbaum and his colleagues have managed to build a different kind of machine learning algorithm ( 算 法 )—one that, like humans, can learn a simple concept from very few examples and can even apply it in new ways. The researchers tested the model on human handwriting, which can vary sharply from person to person, even when each produces the exact same character.
The scientists built an algorithm with an approach called Bayesian program learning, or BPL, a probability-based program. This algorithm is actually able to build concepts as it goes.
In a set of experiments, the scientists tested the program using many examples of 1,623 handwritten characters from 50 different writing systems from around the world. In a one-shot classification challenge, people were quite good at it, with an average error rate of 4.5 percent. But BPL, slightly edged them out, with a comparable error rate of 3.3 percent. The scientists also challenged the program and some human participants to draw new versions of various characters they presented. They then had human judges determine which ones were made by man and which were made by machine. As it turned out, the humans were barely as good as chance at figuring out which set of characters was machine-produced and which was created by humans.
The findings could be used to improve a variety of technologies in the near term, including for other symbol-based systems such as gestures, dance moves and spoken and signed language. But the research could also shed fresh light on how learning happens in young humans, the scientists pointed out.
1. What is the passage mainly about?| A．An advance in artificial intelligence. | B．A special learning program for students. |
| C．The application of artificial intelligence. | D．A new approach of developing programs. |
| A．students are better at processing data | B．computers are incomparable to students |
| C．students are less smart than computers | D．computers are less clever in some aspects |
| A．Humans were slow at recognizing characters. |
| B．BPL wrote characters in a quite different manner. |
| C．BPL could identify and write characters as humans. |
| D．Humans could create more characters than computers. |
| A．Computers learn in the same way as humans. |
| B．The findings may help improve human-learning. |
| C．Machine-learning is superior to human-learning. |
| D．Young humans can understand algorithms quickly. |
