As they migrate(迁移), butterflies and moths(飞蛾) choose the winds they want to fly with, and they change their body positions if they start floating in the wrong direction. This new finding suggests that insects may employ some of the same methods that birds use for traveling long distances. Scientists have long thought that insects were simply at the mercy of the wind.

    Fascinating as their skills of flight are, migrating behavior has been difficult to study in insects because many long distant trips happen thousands of feet above ground. Only recently have scientists developed technologies that can detect such little creatures at such great heights.

    To their surprise, though, the insects weren't passive but active travelers on the winds. In autumn, for example, most light winds blew from the east, but the insects somehow sought out ones that carried them south and they positioned themselves to navigate(导航) directly to their wintering homes.

    Even in the spring, when most winds flowed northward, the insects didn't always go with the flow. If breezes weren't blowing in the exact direction they wanted to go, the insects changed their body positions to compensate(抵消). Many migrating birds do the same thing.

    The study also found butterflies and moths actively flew within the air streams that pushed them along. By adding flight speeds to wind speeds, the scientists calculated that butterflies and moths can travel as fast as 100 kilometers an hour. The findings may have real-world applications.

    With climate warming, migrating insects are growing in number. Knowing how and when these pests move could help when farmers decide when to spray their crops.

    A new report from the International Bar Association (IBA) suggests machines will mostly likely replace humans in a growing number of occupations. One of the authors of the report, Gerlind Wisskirchen, believes that governments need to introduce human quotas（配额）in some sectors in order to protect jobs.

    The report suggests that the jobs at risk are common ones, such as accountants and lawyers. Financial services are more at risk than legal roles though, as algorithms（计算机程序）are easier for a computer to solve when compared to keeping client relationships and making new laws. Simple physical work is also in the firing line, the authors mention.

    As the world population heads toward 7 to 10 billion, futurist Morris Miselowski says, “I am not sure that this nine-to-five, Monday to Friday work as we understand it, will continue for many of us for the next couple of decades.” He forecasts that the biggest changes will be a shift（转变）away from the traditional work time..

“Artificial intelligence (AI)（人工智能）… and all sorts of new technologies are just about to happen; all of that's going to change where, how and when we do work.”

Ms Wissfikirchen was surprised by how far-reaching the effects of automation（自动化）are.

     “Even though automation began 30 years ago in the blue-collar sector, the new development of artificial intelligence and robotics affects not just the blue-collar sector, but the white-collar sector,” said Ms Wisskirchen.

    Toby Walsh, professor of Artificial Intelligence at UNSW, said there was a ray of hope when it came to technology and the future of jobs.

“It's always good to remember that although technology will take jobs away as they raise in this report, there will also be new jobs created by technology,” he said. “In fact if we look at the history of technology since the Industrial Revolution, more jobs have been created than destroyed.”

    When you're having a hard time with your homework or when you're preparing for your term paper, these student-focused websites can help you with just about anything you need. The key to getting the most out of these online resources is to know how they can best be used to your advantage.

Facebook

    Although Facebook can be one of your biggest time-wasters and distractions when you are supposed to be getting work done, it can also be one of your most valuable resources. Most of your classmates will probably have a Facebook account, so anyone you need to connect with about a class you missed or about a problem is usually just a few clicks away.

SparkNotes

    With a free library of history timeline, philosophy study guides and library summaries, SparkNotes has covered just about any reading-related jam you find yourself in. Just run a search for the book, play, or short summary of the material you are supposed to read.

Amazon.com

    Do you finish every term with many expensive textbooks you will never open again? Instead of letting the money spent go to waste, get back some of your cash by selling your books on Amazon.

RateMyProfessors.com

    Choosing new classes can sometimes be like trying to pick out your clothes in the dark, a total guessing game. Which teacher gives out the hardest problem sets? How much homework will that history professor give you every week? At RateMyProfessors.com, students all over the country rate their professors on quality, helpfulness, and how hard their classes are.

 Wikipedia

    While Wikipedia isn't aimed specifically at students, it is difficult to think of another website that does more to reduce the pain of paper writing and researching. Wikipedia gives you a quick way to find sources and get the details of almost any topic you need to research — all without walking to the library.

    The United States will introduce a new and comprehensive(综合的) exam for students who seek to study in American and other English-speaking countries, Xinhua News Agency reported from New York.

    The exam, which stands for a great change from the current English level test, was disclosed by Theresa Chang Wei Jen, associate director of the International Service of the US College Board, America's leading educational organization.

    The Advanced Placement International English Language (APIEL) will be offered for the first time throughout the world on May 10, 2002, said Jen.

    However, the APIEL is a strange title to most Chinese students, and it is unlikely to soon gain the similarity of other already existing exams, such as the TOEFL(Test of English as a Foreign Language), the GRE(Graduate Record Examination), or the IELTS(International English Language Testing System).

    "I have never heard of such a test and I would prefer the IELTS if I need another exam," said Xu Jingyan, a graduating student from Beijing University of Aeronautics and Astronautics, who wants to study in England and has already taken the TOEFL.

    Most of Xu's classmates have never heard of the APIEL. "The APIEL is designed for international students who wish to get university studies in English-speaking countries, including the United States, Britain, Canada, and Australia." said Jen.

    The APIEL has been adopted, said Jen, because the TOEFL can no longer accurately reflect the abilities of students of using the English language comprehensively in an academic environment. Xinhua reported that a fairly large number of foreign students who earned high scores in TOEFL exam turned out to be very ordinary educational performers after admission.

    Compared with the TOEFL, the APIEL measures a student's ability to read, write, speak and understand English through testing his or her skills in listening comprehension, speaking with accuracy(精确) and resourcefulness, and writing with clarity(清晰) and fluency, Jen said.

    Some spiders hunt on the ground, others build webs to trap their food, but the grass water spider catches its prey by running along the surface of the water.

    This special water spider lives on the grassy banks of streams where mosquitoes, damsel flies and other insects come to feed and breed.

    Although it is one of the largest spiders in New Zealand, it has an unusual ability. It doesn't disturb the water as it waits for its meal, and there is barely a ripple(波纹) when it skims(掠过) across the surface at lightning speed to catch its prey.

    Grass water spiders deal swiftly with larger insects like damsel flies by pulling their heads under the water and holding them there until they drown.

    After a meal, the grass water spider spends up to half an hour grooming(修饰) itself. It wipes its eight eyes, brushes its antennae(触角), and takes special care to clean the hairs on its body.

    It is the hairs that trap tiny bubbles(泡沫) of air so that the spider can run down a blade(叶片) of grass and stay underwater for up to an hour when it is frightened. The hairs also keep the spider dry, even underwater.

    It is only when the female spider is caring for the young that she does not hunt on the water. After mating, she produces a large egg sac(囊), which she carries around for five weeks. Once the eggs start to hatch, she attaches the sac to some blades of grass or a thistle. She then tears the sac open and releases the tiny spiders into the nursery web.

For most of us, walking is something we do automatically. It doesn't require much effort, so many of us fail to remember the benefits of walking for health.

Physical activity doesn't need to be hard. Whether you're regularly active or not, even a quick ten-minute daily walk can deliver a host of health benefits. But what happens if we stop walking ahead and start challenging our brains and bodies by walking backwards? Not only does this change of direction demand more of our attention, but it may also bring additional health benefits.

One of the most well-studied benefits of walking backwards is improving stability and balance. Walking backwards can improve how a person walks and balance for healthy adults and those with knee problems. Walking backwards causes us to take shorter, more frequent steps, leading to improve the muscles of the lower legs. But the benefits of changing direction aren't just that- -an interest in backwards movement has led researchers to discover various other benefits. While normal walking can help us maintain a healthy weight, walking backwards may be even more effective. Energy expenditure when walking backwards is almost 40 percent higher than walking at the same speed forwards, with one study showing reductions in body fat for women who completed a six-week backwards walk.

Walking backwards is simple, but that doesn't mean it's easy. So, how can you add walking backwards into your exercise plan? When walking backwards, we're more likely to crash into something or fall over, so in the interest of safety, it's best to start indoors where you won't crash into someone or outside in a flat, open area. Look over your shoulder. Keep your head and chest upright while reaching back with your big toe for each step, rolling through the foot from toe to heel. Once you become more confident walking backwards, you can begin to speed things up.