Look into hunters' eyes

    Have you ever been face to face with a cat or a sheep? If you have,you probably noticed that cats narrow their eyes to vertical (垂直的) slits (狭缝),while sheep have horizontal pupils (瞳孔).

     Why is the difference?

    Scientists from the Universities of California Berkeley and Durham in Britain may have the answer. Their research, published recently in the journal Science Advances, suggested that pupils' shapes could tell whether an animal is a hunter or gets hunted.

    The researchers took a close look at the eyes of 214 land animals.The challenge was to see if they could find a relationship between an animal's role in the food chain and the pupils' shapes.

    They found a pattern. Species with pupils that are vertical slits are more likely to be small ambush predators (捕猎者) – creatures that lie in wait for their lunch.In contrast,those with horizontal pupils are more likely to be plant-eating prey (猎物) species.

    Evolution chose the arrangement for a good reason.For hunters such as household cats,it appears that vertical pupils not only improve their ability to keep track of moving objects like mice,but also maximize (使最大化) their ability to judge the distances of the animals they hunt.

    However, an interesting discovery from the study is that the slit pupils are mostly linked to hunters that are close to the ground. Therefore, bigger cats who actively hunt down their prey, like tigers and lions, don't have slit pupils.

    On the other hand, for plant-eating prey animals, horizontal pupils give them a wider field of vision.When stretched (伸展) horizontally,the pupils allow for more light to enter from the front, back, and sides. Meanwhile, they also limit the amount of light from the sun above so the animal can see the ground better.“ Once they do find a predator,they need to see where they are running,” said leading researcher Martin Banks,a UC Berkeley professor of optometry (视光学).“They have to see well enough out of the corner of their eye to run quickly and jump over things.”

    But what happens when they bend down to eat? Researchers checked this by watching prey animals in the Oakland Zoo in California, US. They believe that when goats lower their heads to eat,their eyes rotate (旋转) to keep their pupils horizontal.

    So it seems that the eyes are indeed the window to the soul!

    Have you ever lost your direction? Then you might find satellite navigation(satnav) systems(卫星定位系统) helpful.

    A satnav system uses groups of satellites. They send information to a receiver(接收器), such as your smartphone. Then they can find where you are.

The earliest satnav system is the Global Positioning System(GPS) of the United States. The US has put 24 satellites into space to make sure GPS can locate(定位) a person correctly and globally. Likewise, Russia's GLONASS and European Union's Galileo can also work globally.

    But China is catching up, building its own BeiDou Navigation Satellite System. BeiDou is China's homegrown satnav system, reported Xinhua. It was set up in 2000, when China sent BeiDou's first navigation experiment satellite into space. With it, China became the third country to build a satnav system after the US and Russia.

    BeiDou can find you wherever you are. It helps you go faster by finding shortcuts(捷径) and using correct directions. When you are in trouble and call the police, they will know exactly where you are if you have a cellphone that uses BeiDou.

    Today, there are more than 20 BeiDou satellites above our heads. And the system is able to offer open services to the Asia-Pacific region(亚太地区).

    In November, China plans to send more BeiDou-3 satellites into space. BeiDou-3's position accuracy(准确度) is less than five meters, Ran Chengqi, a senior designer of the satellite navigation system, told China Daily.

    By 2020, BeiDou is planned to have 35 satellites and begin serving globally, reported Xinhua.

    Susan was born as the ninth child in a Catholic family. She suffered from learning disabilities ever since her birth because of her mother's poor health.

    School was difficult for Susan and she was bullied because of her different behaviors. Her siblings, who were much older, had life experiences that were unknown to their little sister. From the time of her birth, Susan was a screamer. The only really safe place that she would use as a repeat was her bedroom. There she would hang posters of her musical idols on the wall and sing popular music into a hairbrush that she pretended was a microphone.

    One by one the siblings moved away from home and then Susan's father died. This left her alone with an aging mother and a cat. The siblings accused her mother of not expecting more out of Susan. She had seen many professionals and remembered hearing the word “borderline” but didn't know what it meant. She tried volunteer work. Her best state of mind, however, was found when she was singing and so she would regularly join others in karaoke or pubs where she could show her skills and receive appreciation from the crowd.

    When Susan announced at Christmas that she was planning to compete in the Britain's Got Talent contest, her siblings tried to discourage her. It was a wonder that she was even able to do the audition considering the troubles she faced just physically getting to the right place.

    “The Woman I Was Born to Be” is a beautiful story written in the simple but humorous voice of the author, Susan Boyle. She tells her story from birth to the present in an interesting and educational manner. The writing is supplemented by photos from her albums.

    I love this book! In fact, I read the whole thing in one day!

There is something in the stories that not only teaches the reader but also inspires us to reach for our dreams — no matter how impossible they may seem to be!

    Throughout history scientists have risked their health and their lives in their search for the truth.

    Sir Isaac Newton, the seventeenth century scientist, was very smart, but that didn't stop him from doing some pretty stupid things. In his laboratory in Cambridge he often did the strangest experiments. Once, while testing how light passes through lenses (晶状体), he put a long needle into his eye, pushed it to the back, and then moved it around just to see what would happen. Luckily, nothing long-lasting did. On another occasion he stared at the sun for as long as he could bear, to discover what effect this would have on his sight. Again he escaped suffering permanent damage, though he had to spend some days in a darkened room before his eyes recovered.

    In the 1750s the Swedish chemist Karl Scheele was the first person to find a way to produce phosphorus (磷). He in fact discovered eight more chemical elements including chlorine (氯), though he didn't get any praise for them. He was a very clever scientist, but his one failing was a curious habit of tasting a little of every substance he worked with. This risky practice finally caught up with him, and in 1786 he was found dead in his laboratory surrounded by a large number of dangerous chemicals, any of which might have been responsible for his death.

    Eugene Shoemaker was a respected geologist. He spent a large part of his life studying craters (火山口) on the moon, and how they were formed, and later did research into the comets of the planet Jupiter. In 1997 he and his wife were in the Australian desert where they went every year to search for places where comets might have hit the earth. While driving in the Tanami desert, normally one of the emptiest places in the world, another vehicle crashed into them and Shoemaker was killed on the spot. Some of his ashes (骨灰) were sent to the moon aboard the Lunar Prospector spacecraft and left there — he is the only person who has had this honor.

    Unlike most other holidays, the history of April Fools' Day, sometimes called All Fools' Day, is not totally clear. The only point in time that can be agreed on as the beginning of this tradition was 1582, in France. Before that year, the New Year was celebrated for eight days, beginning on March 25th. The celebration reached the highest point on April 1st. With the reform of the calendar under Charles IX，the Gregorian calendar(公历，阳历) was introduced, and New Year's Day was moved to January 1st.

    However, because in those days communications were not as developed as they are today, many people did not receive the news for several years. Some people refused to accept the new calendar and continued to celebrate the New Year on April 1st. These backward people were considered "fools" by other people. They  were often sent on "fools" errands(徒劳无益的工作)  or were made the targets of jokes.

    This developed, over time, into a tradition of playing a trick on someone on the first day of April. The tradition eventually spread to England and Scotland in the eighteenth century. It was later introduced to the American colonies of both the Britain and France. April Fools' Day thus developed into an international fun feast, so to speak, with different nationalities specializing in their own kind of humor at the expense of their friends and families.

    While faking and fierce looks are among animals great defenses, many species know that everyone runs from a big stink (臭气) too.

    Vulture (秃鸳)

    Vultures, are street sweepers that feast on the rotting flesh of dead animals, which benefits us by ridding our highways and landscapes of animal bodies and the bacteria they might carry. When vultures feel threatened they vomit, and the smell of vomited-on dead bodies puts of most predators. Throwing up allows the vulture to fly away more quickly-and the vomit can hurt the aggressor's eyes and face.

    Opossum (负鼠)

    In some ways opossums have it easy. In order to become "dead", they don't have to fax anyone a death certificate. They just lie there with their tongues hanging out with the smell of dead flesh, sometimes for hours, effectively convincing potential predators they can find a much fresher meal elsewhere. Even if they keep getting attacked, they won't move any more than a human statue until the threat has passed.

    Hoatzin (磨雉)

    Hold your nose and meet the hoatzin, a bird of distinctions, not the least of which is that it smells like fresh cow shit. The animal mostly eats leaves and it's the only bird known to digest by fermentation, like a cow. This process is what causes its smell and has earned it the nickname the "stink bird

    Millipedes (千足虫)

    Millipedes are tricky. For starters they look wormy. Their name is deceptive, too: Their legs number about 750. Their major defense is to curl up into a ball. They, though, also release a harm eyes, and leave a horrible smell on their attackers.

    Sea Hare (海兔)

    The graceful sea hare is plain in taste in the first place, so it's not the most popular dish in the seafood chain. Nonetheless this type of sea creature has a pretty creative smell-related defense that is almost the opposite of its smelly companions on this list. The sea hare gives out a slimy, purple ink, the substance which makes food less palatable to predators.

    Researchers using lobsters (2-f) as model predators found that the sea blocks the lobsters receptive mechanism. In other words, the sea hare gives its attacker the equivalent of a stuffy nose so they don't know how appealing it is.