A recent study suggests that groundwater is an answer to water shortages in African countries south of the Sahara Desert, This finding could help millions of people in an area which is expected to be strongly affected by climate change.
WaterAid, an international non-profit group, and the British Geological Survey (BGS), a British government organization, carried out the research.
The report released in March said underground water could help develop agriculture in the area. Additional water resources could help farming in an area where only three to five percent of agricultural land is irrigated (灌溉). For example, BGS information shows Senegal has an aquifer (地下水层) that has been kept in good condition by years of rainfall
“We can’t drink enough to satisfy our thirst,” said Oumou. Drame. She is 40 years old and a mother of five. “We don’t sleep at night.
| A．Tata Bathily is a village in northern Senegal. |
| B．But getting to the water is difficult and costly. |
| C．We leave our children at home to fetch water. |
| D．That is ten times deeper than the wells in Tata Bathily. |
| E．Improvements in the existing water supply may take time. |
| F．Many people think the hot weather is partly to blame for the water shortage. |
| G．They found that underground water could deal with at least five years of drought. |
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【推荐1】If you believe that scientists and artists are most creative when they're young, you are missing an important part of the story. A new study published in De Economist looked at Nobel Prize winners in the field of economics. It found there are two different peaks of creativity. One comes early in a person's career, while another comes later.
The research supports previous work by the authors that found similar patterns in the arts and other sciences.
"We believe what we found in this study isn't limited to economics, but could apply to creativity more generally," said Bruce Weinberg, lead author of the study and professor of economics at The Ohio State University.
"Many people believe that creativity is exclusively associated with youth,but it really depends on what kind of creativity you're talking about."
In the study, those who did their most groundbreaking work early in their careers tended to be "conceptual" innovators(创新者).
These type of innovators "think outside the box", challenging conventional wisdom and suddenly coming up with new ideas. Conceptual innovators are not yet immersed(沉浸于)in the accepted theories of their field, Weinberg said.
But there is another kind of creativity, he said, which is found among "experimental" innovators. These innovators accumulate knowledge through their careers and find new ways to understand it.
The long periods of trial and error for important experimental innovations come later in a Nobel laureate's(荣誉获得者的)career.
"Whether you hit your creative peak early or late in your career depends on whether you have a conceptual or experimental approach," Weinberg said.
The researchers took a novel, empirical(经验主义的)approach to the study, which involved 31 laureates. They arranged the laureates on a list from the most experimental to most conceptual.
This ranking was based on the laureates' most important work, classifying them into "conceptual" or "experimental".
After classifying the laureates, the researchers determined the age at which each laureate made his most important contribution to economics and could be considered at his creative peak.
They found that conceptual laureates peaked between ages 25 and 29. Experimental laureates peaked when they were roughly twice as old, in their mid-50s.
"Our research suggests that when you're most creative is more about how you approach your work."
1. What did the study published in De Economist find?| A．Creativity comes at any age, young or old. |
| B．Creativity tends to decrease as people get older. |
| C．Economists, artists and other scientists have much in common. |
| D．Economists are more creative than artists and other scientists. |
| A．Follow rules strictly. |
| B．Experiment on boxes. |
| C．Break old thought patterns. |
| D．Figure out how to escape from a box. |
| A．They usually come up with new ideas all of a sudden. |
| B．They make discoveries through constant trial and error. |
| C．The majority of them reach their creative peak in their twenties. |
| D．They make more contributions than "conceptual" innovators. |
| A．One's personality type. |
| B．What kind of job one takes. |
| C．How one handles their work. |
| D．One's attitude toward their work. |
【推荐2】People have long watched moths (飞蛾) and other flying insects flock to streetlamps, lights and flames. These insects appear attracted by the light. But a new study suggests they may just lose track of which way is up.
Previous theories say light probably blinds flying insects so that they get trapped by the light, or maybe they interpret light at night as a place to fly for a quick escape. Now the new study suggests flying insects instead turn their backs to the sky’s light to keep their feet pointing toward the ground. Insects naturally turn their backs toward light. But when that light is from an artificial source, it may affect their sense of direction, leading to them flying in circles or diving toward the ground.
At a field station in Costa Rica, Samuel Fabian, an entomologist from Imperial College London in England and his teammates set up hanging and standing lights, and then used high-speed cameras to track wild, flying insects including moths and flies. Some circled the lights endlessly, and others flew sharply upward, losing speed until they couldn’t fly any higher. When the light source pointed up, some insects turned around and headed for the ground. During the flight, the insects always kept the lights at their back even if they’d end up crashing. Crash landings were common when the team lit up a white sheet on the floor. But not when a white sheet — stretched into a height above the floor—was bathed in diffuse (漫射) light, much as the sky would be, insects flew through the area without getting trapped by the light.
The team also observed some species in a lab. Moths and dragonflies generally behaved like the wild insects, and they kept the light at their backs. However, in the lab, fruit flies, like oleander hawk moths — which can fly in the dark — could fly over LED lights without being thrown off course. In the wild, though, the moths still crashed. Maybe this is because, Fabian says, the insects can sometimes control their response to light, or over time, they might learn to avoid artificial light.
1. Why do insects naturally turn their backs toward light?| A．To get close to the light. | B．To escape being caught quickly. |
| C．To protect their feet better. | D．To track where the ground is. |
| A．Artificial light at night could put insects on a crash course. |
| B．Artificial light signaled an escape route for the insects. |
| C．The insects had a better sense of direction. |
| D．The insects were flying toward the light. |
| A．To stress the importance of the study. | B．To prove the previous theory. |
| C．To tell the existence of the exception. | D．To explain the flight pattern. |
| A．Artificial Light Makes Insects More Adaptable | B．Insects May Lose Track near Artificial Light |
| C．The Ways to Get Rid of Light Pollution | D．Insects Learn to Fly for a Quick Escape |
【推荐3】The artificial lighting which lines the world’s coastlines could be having a significant effect on species that rely on the moon and stars to find food, new research suggests.
Creatures such as the sand hopper orientate（确定方位）their nightly migrations based on the moon’s position and brightness of the natural night sky. However, a study by Bangor University and the University of Plymouth shows the presence of artificial light coming from cities several kilometres away (also known as artificial sky glow) disrupts the lunar compass they use when covering long distances.
In some cases, this can lead to animals travelling towards the sea and away from food, while in others it reduces the chance of them risking out for food at all. Writing in Current Biology, researchers say this could throw a clear threat not just to the health of sand hopper populations (沙蚤种群)but also the wider ecosystem, since they play an important role in breaking down and recycling algae (海藻)washed up on coastlines.
Dr. Thomas Davies, Lecturer in Marine Conservation at the University of Plymouth (UK), said, “Artificial sky glow is the most geographically widespread form of light pollution. Surveys have shown it can currently be detected above 23% of the world’s coasts nightly, and with coastal human populations set to at least double by 2060, its effects are only going to increase. Our results show it is already having obvious effects on biological processes that are guided by celestial（天上的）light signals.”
Through the study, researchers find increasing proofs that light pollution from coastal cities can influence marine species inhabiting nearby beaches, rocky shores and even the seafloor. These results highlight how massive city lighting could be in shaping the ecology of coastlines kilometres distant from their nearest urban centres. They also highlight the potential for artificial sky glow to affect other species that undergo migrations using the moon as a compass.
“While our understanding of the effect of street lights on nature has improved greatly, artificial sky glow has been largely overlooked. More work is urgently needed to fully understand the degree to which it is shaping the natural environment.” Dr. Thomas.
1. Which of the following could best replace “disrupts” in paragraph 2?| A．disturbs | B．makes |
| C．unites | D．replaces |
| A．Light pollution is more serious in coastal cities. |
| B．Artificial light has been widely used in the world. |
| C．Artificial light is of great use to animals’ migrations. |
| D．Light pollution caused by artificial sky glow is on the rise. |
| A．It is the main pollution in cities. |
| B．It shapes the ecology of the ocean. |
| C．It has a great effect on surroundings. |
| D．It affects the migrations of sea creatures. |
| A．It is useless. | B．It is quite necessary. |
| C．It is doubtful. | D．It is challenging. |
