In 2009, biologist Charles Anderson put forward an assumption that globe skimmer dragonflies (蜻蜓) on the Maldives had flown in from what he assumed was India. When they flew off again, it was towards East Africa. 12 years later, a group of researchers decided to investigate his claim.
Globe skimmer dragonflies are too small to be fitted with electronic devices. Instead, the researchers examined its physical aspects and calculated how long a globe skimmer dragonfly could stay in the air using the energy that can be stored in its body. In addition, the researchers used wind models to determine if there are winds that facilitate the migration in both directions.
“Our study shows that this migration from India to East Africa is actually possible. However, the globe skimmer dragonfly can’t manage it using only the fat in its body. It also requires favorable winds and these are present during certain periods of the year,” says Johanna Hedlund, a biology researcher at Lund University.
According to the migration experiments using wind models, about 15 percent of the dragonflies could manage the migration from India to Africa in the spring. In the autumn, 40 percent could make the same journey in the opposite direction.
Johanna Hedlund and her colleagues consider it impressive that dragonflies can do this at all. Even more impressive is the fact that the globe skimmer dragonfly migration across the Indian Ocean is the longest in the animal kingdom in relation to an animal’s size.
Other animals also rely on favorable wind conditions when they migrate. Two examples are the amur falcon and the Jacobin cuckoo, which also fly across the Indian Ocean. The researchers warn that climate change may affect the chances of these birds and the globe skimmer dragonfly in the future. There is a risk that wind patterns will change when the water surface gets warmer.
1. What can be learned from the text?A.The dragonfly flies using the fat in its body. |
B.The dragonfly flies the longest in the animal world. |
C.Charles Anderson spotted dragonflies flying to India. |
D.15 percent of the dragonflies left Africa for the Maldives. |
A.By fitting electronic devices. | B.By giving examples. |
C.By performing experiments. | D.By making comparisons. |
A.To illustrate how the animals fly. |
B.To warn people of the climate change. |
C.To evidence that water surface gets warmer. |
D.To show the influence of wind on the migration. |
A.Wind conditions are crucial to dragonflies. |
B.Climate change may affect animals’ migration. |
C.Dragonflies can migrate across the Indian Ocean. |
D.Johanna and her colleagues investigate dragonflies. |
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【推荐1】Pets are an important part of our lives, staying with us and providing unconditional love. We find so much joy with them.
Talk to a sympathetic listener.
Consider a ceremony. The love for your pets never has to end. They can live on in your heart and memory forever. Although you miss them deeply, it can be helpful to honour them and celebrate the wonderful time you spent together. Many people choose to hold some sort of ceremony.
A.Recover with Dr. Time’s help |
B.Beat the heavy blow with confidence |
C.That’s why we feel deep sorrow when a pet dies |
D.But there is no one-size-fits-all response to death and loss |
E.Pets are increasingly viewed as important family members |
F.Pets, as everybody knows, help their owners get rid of loneliness |
G.Making photo books of your pets can be another way of remembering them |
【推荐2】Much like people whose relatives or friends have died, orphaned (成为孤儿的) elephants get by with a little help from their friends, according to a study.
Scientists in the United States and Kenya analysed stress hormones (激素) in the baby elephants whose mothers had died, expecting to find higher levels. Instead, the support of their peers appeared to reduce the orphans’ level of anxiety.
The study, published last week in the journal Communications Biology, concluded that social relationships have a psychological impact on the young elephants. Elephants have strong familial and group ties. Before the age of nine, baby elephants rarely move away more than 30 feet (nine metres) from their mothers, and even a few hours of separation lead to joyous reunion. The bond between female elephants and their young has long been thought to reduce stress.
Expecting to find that the orphaned elephants, which tend to die early at a higher rate than those whose mothers are still alive, would be more depressed, the team analysed stress hormone levels in the waste matter of 36 young elephants in the nature reserves in northern Kenya between 2015 and 2016. Twenty-five of the elephants had lost their mothers to drought or hunting between 2009 and 2013, when a rise in the demand for ivory left many elephants on the reserves motherless.
However, the researchers were surprised to find that long-term stress hormone levels were similar among orphans and elephants with living mothers. Jenna Parker, the study’s main author and a professor at Colorado State University, said their unexpected resilience is directly linked to social support from other elephants, specifically companions of a similar age. Those with more “friends” had significantly lower stress hormone levels. The results may encourage elephant orphanages to pair up animals to help them to recover from loss and adapt to future threats.
It could be a timely move as interactions between humans and elephants are on the rise, thanks in part to drought related to climate change. Experts say the increased conflict is a threat to Kenya’s 36,000 strong elephant population.
1. What did the scientists focus on about orphaned elephants in the study?A.Their peers. | B.Their family. | C.Their psychology. | D.Their growth. |
A.Separation is necessary for younger elephants. |
B.Young elephants are attached to their mothers. |
C.Younger elephants are fond of wandering alone. |
D.Female elephants dominate young elephants’ life. |
A.Difference. | B.Anxiety. | C.Recovery. | D.Result. |
A.Orphaned Elephants Find Relief in Friends. |
B.Elephants Have a Strong Bond with Mothers. |
C.Stress Levels are Higher in Young Elephants. |
D.Orphaned Elephants Have Been Suffering a Lot. |
【推荐3】Lately, the concerns about bees being endangered have become widely noted among people all over the world, but how to take action about it has become scarce in this age. That’s why World Bee Day exists to educate people about the importance of bees and how they can help preserve them for the sake of the future. If you want to help save these fuzzy insects from extinction, then read down below to learn more about what World Bee Day is about!
World Bee Day corresponds (相一致) with an important influencer in the pioneering of beekeeping. Anton Jansa, who in the 18th century pioneered modern beekeeping techniques in his native Slovenia, was one of the first people to help bring about the importance of bees in the world environment. Since then, beekeeping has become a vital necessity in the world’s ecosystems and economic systems. However, not many people realize the importance of bees or know how to help save the bees, which led to the announcement of World Bee Day through the United Nations.
The United Nations set World Bee Day to raise awareness of the importance of bees. Because bees are under a continuous threat from human activity, including the introduction of invasive insects, pesticides and land-use change, which has continuously been destroying bee colonies (蜂群) over time. World Bee Day helps educate people about the importance of bees and what they do for the environment, which includes how they help grow 90% of the world’s wildflower plants, 35% of the world’s crops, and help build ecosystems all over the world. With these statistics, the United Nations has created various programs all over the world to increase awareness of protecting bees and what you can do to help this cause.
If you’re looking for a way to help raise awareness of bee endangerment, then share and spread the news about World Bee Day through social media. If you’re wanting to do more, find a charity that goes towards bee conservation and donates through there. Start a garden and place in a wide arrangement of fruits, vegetables, and flowers that you know bees would like.
1. What’s the purpose of setting up World Bee Day?A.To prove that bees are now endangered. |
B.To teach people ways of protecting bees. |
C.To show the meaning of the scarce bees. |
D.To warn people of the danger of bees. |
A.He was the first to keep bees in his motherland Slovenia. |
B.He used a brand-new technique to keep bees in the 19th century. |
C.He made people know the importance of bees in the environment. |
D.He helped people know the ways to help to save the bees exactly. |
A.To show the number of the world’s wildflower plants is big. |
B.To prove that bees are important to build ecosystems. |
C.To help people understand the necessity of World Bee Day. |
D.To have readers know what to do to protect the bees. |
A.Present colorful pictures of bees on social media. |
B.Share the news of kinds of bees that are dying out. |
C.Raise and donate money for bees with your friends. |
D.Build a garden with many plants in it. |
【推荐1】Superheroes have taken over cinemas for the past 10 years. Superman, Thor, Iron Man, the Black Panther and many more have featured in film series with serious and complex storylines about the end of the universe. However, the makers of Shazam, which came out in China on April 5, have a different take on the superhero movie.
“It’s just a light, funny … action comedy about a boy in a superman’s body,” wrote Owen Gleiberman in his review for Variety magazine.
Billy Batson, the film’s main character, is a 14-year-old who’s spent his life going in and out of foster homes (寄养家庭). One day, on the way to another home, Billy escapes to the subway and meets a wizard (巫师), who gives him magical powers. Whenever Billy says the magic word – “Shazam” – he changes into an adult-sized man with superhuman powers. These new powers include wisdom, strength, stamina, courage and speed. He can also fly.
But how does Billy use his godlike new superpowers? With the help of his new foster brother, Freddie Freeman, Billy tests his strength like any teenager would do – by breaking the rules. He smashes (砸碎) open a soda machine to get free sodas, tricks his teachers, and even buys beer.
While the film is fun and silly, it also has emotional weight. A major part of the story centers on Billy’s search for his real mother. And later, when he faces the villainous Dr Thaddeus Sivana, a former misfit (不合群的人) kid himself, Billy realizes that his new powers can’t fix every problem. He also learns that he has something precious to protect – his new family.
“With strong messages about families of all shapes and sizes and the importance of supporting and nurturing young people, Shazam really feels like the movie we need right now,” wrote Rosie Fletcher at the website Den of Geek.
1. How is Shazam different from other superhero movies?A.It has a complex, serious storyline. |
B.It is about the end of the universe. |
C.It has a light and funny atmosphere. |
D.It has several important characters. |
A.He was born with magical powers. |
B.He has no idea who his real mother is. |
C.He enjoys his time with his foster family. |
D.He lives with a wizard near the subway. |
A.He fails to find his real mother in the end. |
B.He loves playing tricks with his magic powers. |
C.He teaches Dr Thaddeus Sivana to be a good person. |
D.He realizes what his new family means to him. |
A.Tips for a good superhero |
B.Wizards live among us |
C.How to watch Shazam |
D.Super fun superhero |
【推荐2】Learning to Love Locally-Grown Foods
Cooking shows on TV are usually all about foreign foods. Thanks to globalization, people everywhere are introducing their taste buds to dishes from every corner of the world.
For starters, local food is often tastier because it is fresher. Imported goods must be flown or shipped in from far away, so they naturally lose some of their freshness during the journey.
Buying local foods can also have a beneficial impact on the environment. Buying local, consumers can maintain green space and farmland in their communities. Besides, if farmers can sell directly to consumers, they will earn more money for their families. Additional profits also enable farmers to better care for their soil and keep quality standards high.
A.In the end, it’s a win-win situation for both parties. |
B.However, some disagree with the idea of importing foreign foods. |
C.To conclude, the farmers can make money and improve their life. |
D.This causes confusion and makes it difficult to check if any harmful chemicals were used. |
E.At the same time, other people are discovering that food from their area is the best. |
F.If you’re interested in having more local foods, you can even attend a farmers’ market. |
G.Imported goods must also be packaged in plastic or other containers to survive the journey. |
【推荐3】Language learning apps are very popular now and offer opportunities to learn vocabulary and practice grammar. But there has been a discussion about just how effective such apps can be.
Among the most popular apps are Duolingo and Busuu. A former research found positive results on the use of them. But it mainly concentrated on studies with learners who had signed up for language courses and these apps worked as an after﹣class support, so the results were not always reliable. A recent study of 4, 095 Busuu users has been carried out to find out if users can actually learn a language with an app.
Busuu provides learning materials for 12 different languages. It offers special models where some contents are ready for use for free while some contents are not. We find that its users are an even mix of men and women. More than half consider themselves to be at the beginner level because there is a reduction in users as their language levels go up. Most people use the app because of personal interest, or because they want to study or live abroad. Female users are likely to use it less often but for longer periods of time than male users.
Feedback in the app is highly thought of. More than 92% of the users say that the app has met their expectations and 86% consider the app as very good or good. In fact, more than 80% of the users surveyed strongly agree that using the app has helped them improve their knowledge of the language they are learning.
Besides, language learning apps also create an environment where mistakes are only known to the users, and this can address the performance nervousness that many learners suffer from when asked to speak a foreign language. So language teachers should encourage their students to use them to do the grammar work, leaving precious class time for more language communication.
1. What’s the reason why the results of the former research weren’t always reliable?A.It used out-of-date methods. | B.It just focused on positive results. |
C.It was only carried out before class. | D.It only considered users of a limited kind. |
A.All the contents are free to use. | B.Users use it for diverse purposes. |
C.It’s used by more advanced learners. | D.It’s more popular with female learners. |
A.solve. | B.organize. | C.increase. | D.practice. |
A.Students should be required to use apps for homework after class. |
B.Language learning apps are very popular with most language teachers. |
C.Students won’t suffer nervousness in learning languages by using Busuu. |
D.Language learning apps are effective and satisfactory to language learners. |