Birds rely on their keen sense of hearing to detect prey(猎物) and identify other birds on the basis of their songs. In fact, birds have better hearing than humans, so they hear with much more detail. So how do birds hear?
Birds and humans both have an inner ear and a middle ear. However, birds differ from humans in that they lack an external ear structure. Where humans have an outer ear organ, birds have a funnel-shaped(漏斗状的) opening that functions as their outer ear, located on each side of their head. These openings are usually positioned behind and slightly below a bird’s eyes and are protected by soft feathers.
The position of a bird’s head also plays a role in its hearing abilities. Scientists have determined that noises register(显示) at different frequencies on each side of the bird’s head. Depending on the angle from which the noise originates, it registers with a certain frequency in the left eardrum(耳膜) but with a different frequency in the right eardrum. This allows the bird to locate a sound’s origin.
Let’s take a look at owls. They are known for their extremely accurate hearing, which helps them locate prey at night. This hearing ability is partly due to the unbalanced arrangement of the ear openings, with one opening being lower than the other. Sounds register in these openings at slightly different times. Owls can use this time difference, which is only 30 millionths of a second, to determine whether the sounds are coming from their left or their right. Other birds of prey have small covers in front of their ears that help them determine whether sounds are coming from above them or below them. Some owls do appear to have ears on the top of their head, but those are actually feathers controlled by small muscles under the skin that do not affect their hearing at all.
1. According to paragraph 2, what is the major difference between birds’ ears and humans’ cars?A.Size | B.Position. | C.Structure. | D.Function. |
A.Each side of the bird’s head. |
B.Sound quality around the bird. |
C.The angle from which the noise comes. |
D.The difference in frequencies between the eardrums. |
A.To give examples. | B.To present the main idea. |
C.To draw a conclusion. | D.To compare different opinions. |
A.Different Senses of Birds | B.Amazing Abilities of Birds |
C.The Secret of Birds’ Hearing | D.The Origin of Birds’ Hearing |
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【推荐1】Turtles have a problem. They are delicious. And so are their eggs. That has led to the eggs of marine turtles being poached (偷猎).
To deal with the problem Kim Williams-Guillen and Helen Pheasey of the University of Kent, have come up with a handy gadget (小装置). It is a global-positioning-system (GPS) transmitter (发射机) enclosed in a plastic shell made by 3D printing. The result looks like a turtle's egg and weighs about the same. Dug up and carried away by poachers, it can lead the police to those poachers' bases of operation.
As they report this week in Current Biology, Dr Williams-Guillén and Dr Pheasey have now tested their invention in Costa Rica. They placed a decoy egg into each of 101 turtle nests on four beaches where poaching is a problem. The decoys remained inactive until their shells were exposed to the air. At that moment—presumed to signal the arrival of poachers—the “egg” in question starts broadcasting its location once an hour.
In all, 25 of the decoys were poached. They told different stories. Some travelled just a few kilometres, with one ending up at a bar 2km away from the nest it was taken from, where its signal abruptly ended. Others went quite a distance. One, for example, was carried 137km inland, to a supermarket.
To make sure that they, themselves, were not harming what they were intending to protect, the researchers monitored all of the decoy-laden nests which had survived the attentions of poachers and compared these nests' outputs of hatchlings with those of 44 other surviving nests that had no decoy in them. Both sorts of nest had the same hatching rates, suggesting that adding a decoy did not affect the development of the eggs it was hidden among.
Given the success of their project, Dr Williams-Guillen and Dr Pheasey propose that the idea should be used more widely for turtles. They also suggest that similar decoys might help protect the eggs of other endangered reptiles—and birds—that are collected and traded illegally.
1. What is the purpose of the new invention?A.To make man-made turtle eggs. |
B.To track the poachers of turtle eggs. |
C.To protect turtle eggs from poachers. |
D.To locate turtle eggs and send signals. |
A.About a quarter of them were poached. |
B.They appeared different from real turtle eggs. |
C.Their shells would break if exposed to the air. |
D.They gave warnings about approaching poachers. |
A.It may cause widespread damage to turtle eggs![]() |
B.It will help raise people's environmental awareness. |
C.It can be applied to more wildlife conservation fields. |
D.It needs further improvement before being put into practice. |
A.A New Device May Help Stop the Robbery of Turtle Eggs |
B.Researchers Propose a New Idea to Save Poached Turtle Eggs |
C.GPS Will Update Researchers on the Developments of Turtle Eggs |
D.Decoy Eggs Can Help Turtle Eggs Survive the Attention of Poachers |
【推荐2】Humans aren’t the only animals that move to music. Parrots have been known to do it. And now rats have been observed bopping their heads in time with the tunes of Mozart, Lady Gaga, Michael Jackson and others, according to a new study from the University of Tokyo. What’s more, the rats seems to respond to the same beats that get humans’ feet tapping (轻跺).
The researchers played a sonata by Mozart for lab rats at different variations (变更) of the original speed: 75%, 100%, 200% and 400%. Wireless sensors on the rats’ bodies tracked their movements. Meanwhile, 20 human participants were involved and listened to the same music through motion sensor-equipped headphones.
It was observed that the rats’ head movements were the most obvious when the music played at its normal speed, which was around 132 bpm (beats per minute). The same was true for human participants. The researchers then changed to some pop songs such as Lady Gaga’s “Born This Way” and Michael Jackson’s “Beat It”. As with Mozart’s, rats moved their heads along the rhythm of pop songs, similar to how people do, at about 120 to 140 bpm.
The study showed that both rats and humans moved their heads along to the beat in a similar rhythm. The level of head bopping from both humans and rats decreased as the music sped up. The study suggests that there is something similar about the way human and rat brains respond to rhythm, but rats do not match their motions to the beat like humans do. Humans can predict the timing of a beat and move predictably to it.
Aniruddh Patel, a psychologist who studies brain response to music, says humans and parrots respond to beats with big, voluntary movements such as head shaking, dancing or foot tapping. Patel also stresses that this study does not show that rats have the same emotional associations with music as humans do. Yet he believes it could help reveal how humans and some other animals evolved a sense of rhythm.
1. What does the underlined word “bopping” in the first paragraph mean?A.Moving. | B.Responding to. | C.Nodding. | D.Reacting. |
A.They seem more interested in pop music. | B.They make similar movements to different rhythms. |
C.They prefer moving their heads with the beat. | D.They are unable to predict the beat of music. |
A.Uncaring. | B.Doubtful. | C.Positive. | D.Disapproving. |
A.Music affects rats’ brains. | B.Humans are the only animals that move to music. |
C.Music is attractive to rats. | D.Rats may respond to music like human do. |
【推荐3】On a farm in England, Gavin and Alice Munro are taking sustainability (持续性) to the next level: they harvest trees which they grow into chairs.
The couple have a furniture (家具) farm in Derbyshire where they are growing 250 chairs and 50 tables. It is their answer to what they see as the inefficient (效率低的) process of cutting down mature trees to create furniture.
“Instead of growing a tree for 50 years and then cutting it down and making it into smaller and smaller bits ... the idea is to grow the tree into the shape that you want directly. It’s like a kind of 3D printing,” said Gavin.
Part of the inspiration for the idea came when Gavin was a young boy. He found an overgrown bonsai tree (盆景树) which looked like a chair.
The 44-year-old man began experiment in 2006. In 2012, Gavin and Alice set up the company Full Grown. Within several years, the couple developed the most effective way to shape a tree without limiting its growth. They guide shoots (新枝) heading in the right direction, rather than forcing them the wrong way against their natural growth.
The average chair takes six to nine years to grow and another year to dry out. The labor and time involved in producing the organic pieces mean they do not come cheap. Chairs sell for£10,000 each and tables for£2.500 to £12.500.
1. What is special about the farm?A.3D printing is used. | B.Bonsai trees grow there. |
C.It was set up by a couple. | D.Trees can grow into furniture. |
A.By limiting its growth. |
B.By following its natural growth. |
C.By forcing it against its natural growth. |
D.By guiding its shoots in the right direction. |
A.Over 50 years. | B.6 to 9 years. |
C.6 years at most. | D.7 to10 years. |
A.It has brought in huge amounts of money. |
B.Trees grow there inefficiently. |
C.It’s a good try of sustainability. |
D.It will gain popularity soon. |
【推荐1】While international travel is not an option due to the pandemic, Chinese tourists are still traveling within the country. Some people have an option for a more rural experience, though historic and natural wonders are still the priorities.
According to a recent report released by Chinese-owned Trip. com Group, one of the world's largest online travel agencies, rural tourism trips in China had increased year-on-year by more than 300 percent by March 2021.
Zhou Mingqi, founder and general manager of Shanghai Tour Guide Enterprise Management Consulting, said that Chinese people are tired of the hustle and bustle(喧嚣忙碌)of big cities and want to have unique experiences.
"There is a need to experience a different kind of life, like idyllic(田园诗般的)scenery or countryside life, to change a lifestyle on the weekend, " Zhou told CNN.
Wang Shang works for a Beijing-based company that helps organize countryside tours. She said that in one of the hotels she worked for, visitors can experience growing their own food, practice farming and learn about the region's traditional crafts and customs, CNN reported. Deng Yu, a 26-year-old tourist, likes the lifestyle very much. Working in big cities for several years, Deng told CGTN that rural trips help her not only "enjoy the landscape" but also "relieve stress by escaping the bustling city life and getting closer to nature."
Wang believes that experiencing a healthy lifestyle is another reason why city-dwellers travel to rural areas. Most of the visitors from cities are used to buying food in the supermarket. Sometimes they would worry about the food safety. But in rural areas, they can easily get healthy, fresh produce. Wang said that visitors from big cities come to buy flour, noodles, meat, eggs, honey and liquor, among other items.
The trend has also been pushed by Chinese internet influencers such as Li Ziqi, whose beautifully-shot videos of simple life in rural China have gained tens of millions of viewers.
To keep this boom going and attract more visitors, some rural areas are increasing their appeal.
"Nowadays· the rural areas in many places have indeed undergone major changes. Especially after renovating for tourism, it will become much more beautiful than in the past." Zhou told CNN.
1. What do we know about the international travel?A.It is widespread throughout the country. |
B.It declines greatly and suffers a great loss. |
C.It has been replaced by rural tourism trips. |
D.It is not favored by the official government. |
A.They want to change a lifestyle. | B.They feel like living with farmers. |
C.They want to witness the good harvest. | D.They hate working in big cities. |
A.We can learn more about traditional customs. |
B.It is easier to enjoy the scenery and earn some bonus. |
C.People can buy some organic and fresh produce. |
D.Strangers are more likely to be employed. |
A.Cautious. | B.Negative. | C.Doubtful. | D.Positive. |
【推荐2】Starting this year, Scholastic Aptitude Test(SAT)scores will be about more than just how many correct answers a person has on the test.The College Board in charge of the SAT recently published a new policy.It will include something called an "adversity score", based on 31 different factors and ranging from I to 100.A score of 50 is an "average level of disadvantage", said The New York Times.A higher score means a student has faced more adversity.It will cover 150 colleges later this year and be available to all US colleges in 2020.
What kind of adversity do students face? African-American students, for example, are more likely to attend underfunded(资金不足的) schools, and their families usually can’t afford extra SAT lessons.Higher SAT scores have been found to have a close tie with students from richer families and those with better-educated parents, reported The New York Times.As a result, the SAT has long been criticized for its unfairness.
The new adversity score tries to deal with that reality.If a student came from a poor neighborhood or attended a high school without enough funding, this information will be given to college administrators.While one student's SAT score may be lower than her rich classmates, college administrators may assume that she did her best in a bad situation.
This sounds good, but the College Board has received a lot of criticism for this new development.Parents are worried.They’re concerned that their children's hard work would be "completely neglected“(忽视)just because they happened to come from a rich family.
Writing in Time, Andre J.Washington and Daniel Hemel call the adversity score a half-hearted effort".They say the score fails to directly deal with racial inequality(种族不平等).They also say that the problems experienced by African-Americans are deeper than just low scores and school funding.For example, they point out that African-American students are less likely to have supportive relationships with teachers, so they are less likely to have satisfying recommendation letters.
At least they're trying, says Richard D Kahlenberg, a senior fellow aThe Century Foundation.”An imperfect adversity score is better than failing to consider the difficulty so many students get through”, he said."The adversity score is simple and direct.”
1. What does “adversity" probably mean in the passage?A.Mess |
B.Difficulty |
C.Confusion |
D.Failure |
A.Schools are underfunded. |
B.The media have caused the unfairness. |
C.Parents are not well-educated. |
D.Family status greatly affects students' scores. |
A.It will narrow the gap between the white and the black. |
B.Students from poor families are likely to benefit from it. |
C.It will encourage students to work harder for high scores. |
D.Students from rich families may have higher adversity scores.. |
A.It fails to take students' difficulties into consideration. |
B.It will make racial inequality a more serious problem. |
C.The relationship between teachers and students will be affected. |
D.Efforts made by students from rich families will be undervalued. |
【推荐3】From teenage to adulthood, you go through a basket of changes—graduation, jobs and relationships that come and go. But as you grow older, does your personality change?
People tend to think of personality as fixed. But that is not how it works. “Personality is a developmental phenomenon instead of something that you’re stuck with and can’t get over,” said Brent Roberts, a psychologist at the University of Illinois.
Roberts and other researchers have surveyed the personalities of participants regularly over many years, showing that our personality is actually stable within each decade of life. You don’t notice it on a 1-to-5-yeartime range, but in the long term, it becomes pronounced(显著的).
In 1960, psychologists surveyed over 440,000 high school students who answered questions about everything from how they reacted to emotional situations to how efficiently they got work done. Fifty years later, researchers tracked down 1,952 of these students and gave them the same survey. The results found that in their 60s, participants scored much higher than they did as teenagers on questions measuring calmness, self-confidence, leadership and social sensitivity(敏感度).
Over again, studies have found similar results. Personality tends to get “better” over time. Psychologists name it “the maturity principle(成熟定律)”. People become more extroverted(外向), emotionally stable, agreeable and gentle as they grow older. In general, “the maturity principle” applies to most people.
So what causes the change? Evidence suggests it’s not dramatic life events, such as marriage, the birth of a child or loss of a loved one. Instead, changing expectations placed on us—as we adjust to university, the work force, starting a family—slowly wear us in, almost like a pair of shoes, Roberts said. “Over time, you are asked to do things differently and thus learn how to behave in these situations.” So we adapt.
1. What has Roberts found about personality according to the passage?A.It is a stable phenomenon. | B.It changes on a daily basis. |
C.It is a fixed pattern of thoughts. | D.It develops gradually as we age. |
A.By classifying the facts. | B.By making comparisons. |
C.By giving various examples. | D.By quoting previous researches. |
A.An approachable and stable character. | B.A calm and self-centered personality. |
C.A successful and extraordinary career. | D.An unusual and emotional sensitivity. |
A.We have too much work to do. |
B.Dramatic life events have happened to us. |
C.We gradually adapt to different life situations. |
D.It is stressful to behave • ourselves in adulthood. |