The concentric circles (同心圆状斑点), also known as eyespots on butterfly, not only look like real eyes but may also appear to glare directly at predators (捕食者) from many directions, scientists have found. This visual illusion, called the “Mona Lisa effect”, could scare would-be attackers and buy the insects enough time to escape.
Scientists suspect that eyespots, with dark “pupils (瞳孔)” in the center look like real eyes to predators. Hannah Rowland, an ecologist at the Max Planck Institute wanted to see if the direction of this fake gaze contributed to the effect.
First, Rowland and her co-author trained chicks to attack a worm hidden behind a paper printout of two eyespots at the end of a path. When the eyespots’ pupils were specifically pointed in the chicks’ direction, the birds repeatedly ran toward the paper and then backed away, and they waited a few minutes before attacking. But when the pupils instead appeared to look away from the direction of the chicks’ approach, the birds attacked in seconds. Centrally located pupils, though not as effective as ones that stared directly at the chicks, resulted in longer delays than pupils that looked the other way.
“This suggests that they really are paying attention to the direction of the pupils in the eyespots and are perceiving them as eyelike stimulation. The concentric eyespots found most often in the insect world may seem to the chicks like a pair of eyes that follow them regardless of approach angle,” says Rowland.
National University of Singapore evolutionary biologist Antonia Monteiro, who was not involved in the research, says the study is a “cool” demonstration of an evolutionary theory for eyespots. “These butterflies can be encountered from all angles, so having the pupil centrally located ends up being pretty good,” Monteiro says. Still, she says, the eyespots used in the study were several millimeters larger than even the largest commonly found in nature, raising the possibility that the chicks may have been extra frightened by the size of the paper eyes.
1. What is the function of eyespots on the butterfly?A.Making them look more beautiful. | B.Spotting potential dangers. |
C.Helping them identify the direction. | D.Protecting them from being attacked. |
A.They attacked immediately. | B.They turned away in seconds. |
C.They reacted cautiously. | D.They became very excited. |
A.The eyespot is a butterfly’s powerful weapon. |
B.The experiment needs further proof. |
C.The study first proposes an evolutionary theory of eyespots. |
D.Butterflies in nature have small eyespots. |
A.To appeal to readers to preserve butterflies. |
B.To uncover the hidden biological secret of butterflies. |
C.To analyze the social behaviour of butterflies. |
D.To demonstrate the evolutionary theory for eyespots. |
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【推荐1】When I was a baby, I entertained you and made you laugh. Whenever I was “bad”, you'd shake your finger at me and ask, “How could you?”--but then you'd give up, and roll me over for a belly scratch and I believed that life could not be any more perfect.
My housetraining was a long process, because you were terribly busy, but we worked on that together. We went for long walks, runs in the park and car rides. We stopped for ice cream. I took long naps in the sun waiting for you to come home at the end of the day.
Gradually, you began spending more time at work and on your career, and more time searching for a human mate. Eventually, you fell in love. She, now your wife, is not a dog person, but I still welcomed her into our home. I was happy because you were happy. Then the human babies came along and I shared your excitement, I was fascinated by their pinkness, how they smelled, and I wanted to mother them too. Your wife was afraid I would bite them. But nevertheless, as they began to grow, I became their friend.
Now, you have a new job in another city and you and they will be moving to an apartment that does not allow pets. You've made the right decision for your “family”, but there was a time when I was your only family.
I was excited about the car ride until we arrived at the dog pound. It smelled of dogs and cats, of fear, of hopelessness. You filled out the paperwork and said, “I know you will find a good home for her.” They shrugged and gave you a pained look. The children were in tears as they waved me goodbye. And “How could you?” were the only three words that swept over my mind.
Is it better to live with hope or without hope? At first, whenever anyone passed my pen , I rushed to the front, hoping it was you, that you had changed your mind and that this was all a bad dream.
My beloved master, I will think of you and wait for you forever. I hope you receive more faithfulness from your family than you showed to me.
1. Why was the dog excited about the car ride?A.It thought of moving with its master. |
B.It hoped to be adopted(收养)by another family. |
C.It was longing for the life at the pound |
D.It was happy about its master's decision. |
A.the dog had done many bad things | B.the dog would be given less care |
C.the master's decision upset the dog | D.the master left the dog with regret |
A.It felt disappointed with its master. | B.It continued to love its former owner. |
C.It did not trust humans any more. | D.It was excited about the pound. |
A.Be ready for changes. | B.Never expect too much. |
C.Never complain about your life. | D.Be faithful to those who love you. |
【推荐2】Dogs in the classroom lower stress of primary school students, new research has found. The study by UK researchers found spending some time with a dog twice a week was better for reducing stress on students than many other classroom relaxation activities. And the benefits of these “dog dates" were similar for children in both normal and special schools.
Stress is known to negatively affect a child’s learning, behaviour, health and mood. This has led schools to try a number of ways to reduce stress, including yoga, mindfulness, physical activities and even having animals in classrooms.
The researchers from the University of Lincoln measured students' stress levels by tracking the level of the stress in their saliva (唾液). They studied 105 students aged 8 to 9 in four normal schools as well as 44 children of a similar age in seven special schools in the UK. The children were randomly (任意) divided into three groups: a group that spent time with a dog; a group that spent time doing relaxation activities; and a “control” group that did neither of these things. Students in the dog group spent 20 minutes with a trained dog twice a week for four weeks. The relaxation group spent the same amount of time doing exercises.
The researchers found that the children in the dog group had “significantly lower” stress levels, while those in the relaxation and control groups recorded an increase over the school term. The study, which was published in the journal PLOS ONE, also found stress was lowest in the children in the dog group immediately after their contact with the puppies. “Dog-assisted activities can lead to lower stress levels in schoolchildren with and without special educational needs,” University of Lincoln researcher Kerstin Meints said, “but more research is needed to discover what was the ideal amount of time and contact with dogs for the best effect.”
1. What is the benefit of having dogs in the classroom according to the research?A.Relieving stress for students. | B.Making students feel less lonely. |
C.Strengthening students' health. | D.Improving students’ learning ability. |
A.By analyzing causes. | B.By providing examples. |
C.By listing facts. | D.By making comparison. |
A.The proper contact time with dogs still needs further study. |
B.Dogs have more effects on the children in special schools. |
C.The children doing more exercises have the lowest stress level. |
D.The children spending most time with dogs are lowest in stress. |
A.Students need the company of dogs |
B.Classroom dog dates reduce kids’ stress |
C.A new research about dogs is carried out |
D.Dog-assisted activities become popular in UK |
【推荐3】I was mostly based in Samburu National Reserve, recording details of the population and leading collar (颈圈) operations. We put trackers (跟踪仪) around wild elephants’necks, so we can learn about their activities.
In May 2009, in the middle of the wet season, Rommel appeared again. And it was histurn to be placed a collar. We sent three cars out to search for him. There’s a river running through the park where many elephants gather in the mornings. At 10:30 am, one of my partners clocked Rommel.
A tranquillizer (镇静剂) was carefully shot into his body so we could safely place a collaron him, but for a bull of Rommel’s size it could take longer. After that, he turned away, heading in an unexpected direction and seemed to be near danger by killing himself in thewater. It would be a bad accident. Only by pulling his trunk (象鼻) from the river, could weensure his survival. The problem was that the river was a little bit changeable. Immediately, I decided to act. I jumped in and lifted his heavy, twitching trunk from the water with the help of lifeguards. The team tried to fit him with a collar, but we discovered that we didn’t have one big enough.
We couldn’t risk keeping him there while we created a bigger collar. So I struggled on, holding his trunk high with all my strength. And medicine that took away the efforts of the tranquillizer was delivered.
As soon as his ears started to move, a sign of coming to life, I dropped his trunk and moved to safety. Within a couple of minutes, he was back to life. That was one of my proudest moments
1. What is the purpose of putting trackers around wild elephants’necks?A.To record their sizes. | B.To know their activities. |
C.To control and train them. | D.To save them from danger. |
A.To sent him to a zoo. | B.To treat his wounds. |
C.To place a collar on him safely. | D.To check his health. |
A.He gave him certain medicine. | B.He lifted his trunk out of water. |
C.He performed an operation on him. | D.He called other members for help. |
A.Pride. | B.Surprise. | C.Anger. | D.Worry. |
【推荐1】One of the ocean’s noisiest creatures is smaller than you’d expect-snapping shrimp (鼓虾). They create a widespread background noise in the underwater environment, which helps them communicate, defend territories and hunt for food. When enough shrimp snap (发出劈啪声) at once, the noise can dominate the soundscape of coastal waters.
Aran Mooney, a biologist at Woods Hole Oceanographic Institution, suggested that with increased ocean temperatures, snapping shrimp will snap more often and louder than before. This could raise the background noise of the global ocean. “They make a sound by closing a claw so fast. This makes a bubble (泡泡) and when that bubble explodes, it makes that snapping sound,” said Mooney.
Mooney detected a strong relationship between warmer waters and deafening, more frequent snapping shrimp sounds after experimenting with the shrimp in tanks in the lab and by listening to the shrimp in the ocean at various water temperatures. “As the temperature rises, the snap rate increases,” he said. This makes sense because shrimp are essentially cold-blooded animals, meaning their body temperature and activity levels are largely controlled by their living environment. “We can actually show in the field that not only do snap rates increase, but the sound levels increase as well.”
How the louder snapping shrimp would bother or benefit the surroundings remained to be seen. “We know that fish use sound to communicate,” Mooney said. “If the environment gets noisy, it has the potential to influence that communication. That’s something we have to follow up on.” There is also the possibility that the change of snapping shrimp disturbs instruments humans use to detect mines, which could have implications for national defense.
1. What can we know about the snapping shrimp’s sound?A.It has multiple uses. | B.It is vital to the ecosystem. |
C.It is hard to be detected. | D.It aims to protect the shrimp. |
A.By observing snapping shrimp in the field. |
B.By recording the snap rates in the lab. |
C.By analyzing the way shrimp make noise. |
D.By comparing shrimp’s sound in different places. |
A.Applications of shrimp’s sound. |
B.Impacts of the noise on other creatures. |
C.Means of communication among fish. |
D.Methods of preventing shrimp’s snapping. |
A.Underwater World Is No Longer Quiet |
B.Small Animals Make a Big Difference |
C.Warming Oceans Are Getting Louder |
D.Snapping Shrimp’s Noise Speaks Much |
【推荐2】In a digital age, we almost never write things by hand. However, multiple studies have shown that this act has many benefits.
New brain research, led by researchers at the Norwegian University of Science and Technology, confirms the same: choosing handwriting over using a keyboard results in better learning and memory.
“When you write your shopping list or lecture notes by hand, you simply remember the content better afterwards,” said Audrey van der Meer, author of the study.
The study was conducted using equipment to track and record brain wave activity. The participants included 12 young adults and 12 children. This is the first time that children have participated in such a study. Each subject was asked to write by hand and type on a keyboard while wearing a hood (风帽) with over 250 electrodes (电极). The sensors (传感器) in the electrodes are very sensitive and pick up the electrical activity that takes place in the brain. Each examination took 45 minutes per person.
The results showed that the brain in both young adults and children is much more active when writing by hand than when typing on a keyboard. According to Van der Meer, plenty of senses are activated by pressing a pen on paper, seeing the letters written and hearing the sound made while writing. These sense experiences build contact between different parts of the brain, opening the brain up for learning.
Van der Meer believes that the outcomes stress the importance of children being challenged to draw and write at an early age, especially at school. “Learning to write by hand is a bit slower process, but it’s important for children to go through the tiring phase of learning to write by hand,” she said.
The hand movements used to form the shapes of letters can benefit a lot in many ways. “If you use a keyboard, you use the same movement each letter. Writing by hand requires control of your fine motor (精细动作) skills and senses. It’s important to put the brain in a learning state as often as possible,” Van der Meer added. For example, you might use a keyboard to write an essay, but you should take notes by hand during a lecture.
1. What is the author’s main purpose in writing the text?A.To encourage the use of handwriting. |
B.To suggest children starting to write early. |
C.To report on a new research on handwriting. |
D.To explain how handwriting influences adults and children differently. |
A.Writing by hand is easier on the brain. |
B.More senses are made active when writing by hand. |
C.The brain is more used to the skills required to write by hand. |
D.Noise made by typing doesn’t distract the brain when writing by hand. |
A.The study involved 48 participants altogether. |
B.All the participants were gathered together for examination. |
C.The participants were divided into two groups to conduct the study. |
D.The sensors in the electrodes were used to track brain wave activity. |
A.It helps people develop fine motor skills. |
B.It allows people to write better essays. |
C.It allows children to become more patient. |
D.It increases people’s interest in learning. |
【推荐3】Dog people like to point out dogs’ long history as humankind’s best friend while even the most devoted cat owners may wonder at some point whether their cat really loves them.
Look out for scenting (气味)
Cats use scent to identify their own members, by sharing a group scent profile. They have scent glands on their head and around their ears, and often rub their heads against people and objects that are familiar and comforting. Does your cat rub its head or side against your legs?
Look for blinks
Your cat might be secretly signalling their affection in the way they look at you.
One of the most obvious signs that your beloved pet is fond of you, is the way that your cat approaches you. A tail held in the upright flagpole position or shaped in a upright question mark shows a friendly intention. Wrapping their tail around your leg is another gesture that a cat has ultimate trust in you.
Sense their comfort zone
A.Watch their tail and leg |
B.Actually, cats do love their owners, according to science |
C.Cats are very protective of their personal space and don’t like unwelcome guests to invade it |
D.Look out for these behaviors to prove that your furry friend is truly bonded to you |
E.Watch how they greet you |
F.The soft sensation you feel against your legs is actually your cat identifying you as a friend |
G.When cats encounter strange humans or other cats they don’t know, they usually greet them with an unblinking stare |
【推荐1】When starting college, most students enjoy a week’s stay on campus before classes actually begin. What should you do with that time? Below are several tips to ease yourself into college life.
Participating in Campus Welcome Activities
Most universities host welcome events before the academic year officially begins, including freshmen orientations, campus picnics, and entertainments like concerts.
Participating in such events is a great way to learn about school facilities and understand campus culture: What do students do for fun? What are their favorite classes? What is the history of your university? It can help you observe campus life outside the classroom.
Exploring Campus
Getting to know where essential campus resources are—such as the student advising center, psychological services, and the tutoring center—will make your first few weeks on campus a lot easier, because you won’t have to look for them while still getting used to your classes.
Take some time to check out the buildings where your classes will be held. This will prevent you from getting lost in the first few days of classes and familiarize you with how long it takes to get from place to place. If you’re worried about taking classes one after another in different buildings, a quick test run won’t hurt. That way, you will avoid potential time delays in getting to your classes.
Starting a Routine
Before getting too excited about all of the fun things you will be able to do during the week, remember that you do have a pretty big schedule change coming up. Starting classes means being in different places at different times, so it’s a great idea to start getting used to that routine right this week.
What helps you most is to schedule your sleep. Following the planned time will ensure you have enough sleep to get to those early classes and stay wide awake.
If you have other daily routines, such as exercising or talking on the phone with family, work those into your day-to-day life before classes start so that you get a better idea of how they fit in with your schedule.
1. Why are freshmen advised to have a quick test run between buildings?A.To see how many facilities they can use. | B.To avoid being late for future classes. |
C.To help those getting lost on campus. | D.To practice running on their way to class. |
A.On the first day of their classes. | B.Before the orientation week. |
C.After their first-day classes. | D.During the orientation week. |
A.Take physical exercise before class. | B.Leave their phones powered off. |
C.Take early classes every day. | D.Keep to the sleep schedule. |
【推荐2】NASA is planning to send a robot called MIRA to the International Space Station (ISS) by 2024. Its creators claim that MIRA is capable of performing operations on its own and if required, it can also be controlled remotely. Such a device could allow doctors on Earth to perform operations on astronauts in space while controlling the device remotely.
However, before performing surgical (外科的) operations on humans, MIRA will have to pass several tests on the ISS involving non-living objects. These tests will help MIRA learn to perform surgeries in low-gravity conditions, which can be quite a challenge. It is believed that in the future, MIRA could play an important role in helping out astronauts who face medical emergencies on the moon and Mars or during long-distance space travel.
The journey from the ISS to Earth can be completed in six hours. Considering the already available medicines and supplies on the ISS, this may sound like a manageable duration for many of the medical emergency cases occurring there. However, if an astronaut requires immediate medical support on a distant planet like Mars, he or she will probably die by the time help arrives.
Obviously, it is not practical to send all kinds of doctors with astronauts. Therefore, the best strategy to deal with medical emergencies is to have a robot surgeon that could perform all kinds of surgeries. MIRA could achieve this goal as it can be remotely controlled in outer space by a surgeon on Earth. For example, if an astronaut faces both nerve (神经) and bone injury on Mars, a neurosurgeon and an orthopedic surgeon on Earth can perform surgeries remotely on the injured astronaut using MIRA.
But the robot surgeon could be very useful here on Earth as well. After receiving safety approval from the Food and Drug Administration, in the coming years, we might see doctors using this robot to perform surgeries remotely on Earth. This remarkable device could make complicated (复杂的) surgeries practical in even remote and rural areas, where there could be a shortage of doctors.
1. What is MIRA designed for?A.Carrying out operations in an emergency. |
B.Documenting daily activities done by astronauts. |
C.Ensuring sufficient medicines and supplies on the ISS. |
D.Improving the functioning of space operation equipment. |
A.MIRA doing tests on animals in low-gravity conditions. |
B.Scientists bringing down the cost of sending MIRA into space. |
C.MIRA helping out astronauts with medical needs on the moon. |
D.Scientists conducting MIRA experiments on lifeless objects on the ISS. |
A.It offers life support when help arrives. |
B.It offers up-to-date medical equipment for space travel. |
C.It provides life-saving assistance for astronauts on remote planets. |
D.It increases the manageable duration for many medical emergencies. |
A.Taking remote control from Earth. | B.Sending all kinds of doctors into space. |
C.Making surgeries practical in rural areas. | D.Dealing with different types of medical emergencies. |
【推荐3】Search “toxic parents”, and you’ll find more than 38,000 posts, largely urging young adults to cut ties with their families. The idea is to safeguard one’s mental health from abusive parents (虐待型父母). However, as a psychoanalyst (精神分析学家), I’ve seen that trend in recent years become a way to manage conflicts in the family, and the severe impacts estrangement (疏远) has on both sides of the divide. This is a self-help trend that creates much harm.
Today’s social justice values respond to this reality, calling on us to criticize oppressive (高压的) and harmful figures and to gain power for those who have been powerless. But when adult children use the most effective tool they have - themselves - to gain a sense of security and ban their parents from their lives, the roles are simply switched, and the pain only deepens.
Often, what I see in my practice are cases of family conflict mismanaged. I see the terrible effect of that trend: situations with no winners, only isolated (孤立的;孤独的) humans who long to be known and feel safe in the presence of the other.
The catch is that after estrangement, adult children feel abandoned and betrayed. They carry the ghosts of their childhood, tackling the emotional reality that those who raised us can never truly be left behind, no matter how hard we try.
What I have found is that most of these families need repair, not permanent break-up. How can one learn how to negotiate (谈判;协商) needs, to create boundaries and to trust? How can we love others, and ourselves, if not through accepting the limitations that come with being human? Good relationships are the result not of a perfect level of harmony but rather of successful adjustments.
To pursue (追求) dialogue instead of estrangement will be hard and painful work. It can’t be a single project of “self-help”, because at the end of the day, real intimacy (亲密关系) is achieved by working through the injuries of the past together. In most cases of family conflict, repair is possible and preferable to estrangement - and it’s worth the work.
1. Why do young people cut ties with the family?A.To gain an independent life. | B.To restore harmony in the family. |
C.To protect their psychological well-being. | D.To follow a tendency towards social justice. |
A.Response. | B.Problem. | C.Operation. | D.Emphasis. |
A.break down boundaries | B.gain power within the family |
C.live up to their parents’ expectations | D.accept imperfection of family members |
A.By offering causes and effects. | B.By analyzing the problem and solutions. |
C.By comparing strengths and weaknesses. | D.By listing relevant examples and data. |