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!

    Most kids go to school during the day and come home to their families or caregivers at night．Sometimes kids can't go home every night so they board or live at school during term-time．

    Whatever the reason for going to boarding school, living with a group of people is very different from living with your family．You have to learn to get on with others, be responsible for looking after your own stuff and follow the rules that are there to make everyone's life pleasant and safe.

The following are some tips from boarders.

    "Remember that the other new students are probably as shy as you are．If you don't talk first and try to make friends, it may not happen．"

    "Don't hold things back inside you．The more you talk, the easier it gets．You can talk to older boarders as well as adults．They understand what you are feeling—they've been through it too．"

    "Be respectful of others' space and give them privacy．Having people around all the time means you don't get much time to yourself."

    "Join in sports and other afterschool activities．You'll meet lots of new people who are interested in the same things as you．And keeping busy will help you get over feeling homesick．"

    "If you are a weekly boarder or go home most weekends it can be harder to make friends, so see if you can organize to stay in for a weekend."

    "Make friends with non-boarders too．It's good to visit someone's home sometimes."

    "Boarding has its ups and downs, you get homesick and sometimes the food is not that great but most of the time it is like being in one big family．You make friends that you know you'll keep for the rest of your life．"

    Being sociable looks like a good way to add years to your life. Relationships with family, friends, neighbours, even pets, will all do the trick, but the biggest longevity(长寿) boost seems to come from marriage or an equivalent relationship. The effect was first noted in 1858 by William Farr, who wrote that widows and widowers(鳏夫) were at a much higher risk of dying than their married peers. Studies since then suggest that marriage could add as much as seven years to a man's life and two to a woman's. The effect holds for all causes of death, whether illness, accident or self-harm.

    Even if the odds are stacked against you (the conditions are not favourable), marriage can more than compensate. Linda Waite of the University of Chicago has found that a married older man with heart disease can expect to live nearly four years longer than an unmarried man with a healthy heart. Likewise, a married man who smokes more than a pack a day is likely to live as long as a divorced man who doesn't smoke. There's a flip side, however, as partners are more likely to become ill or die in the couple of years following their spouse's death, and caring for a spouse with mental disorder can leave you with some of the same severe problems. Even so, the odds favour marriage. In a 30-year study of more than 10,000 people, Nicholas Christakis of Harvard Medical School describes how all kinds of social networks have similar effects.

    So how does it work? The effects are complex, affected by socio-economic factors, health-service provision, emotional support and other more physiological mechanisms(机制). For example, social contact can boost development of the brain and immune system, leading to better health and less chance of depression later in life. People in supportive relationships may handle stress better. Then there are the psychological benefits of a supportive partner.

    A life partner, children and good friends are all recommended if you aim to live to 100.The best social network is still being mapped out, but Christakis says: “People are interconnected, so their health is interconnected.”

    Play time is in short supply for young children these days and the lifelong consequences for developing children can be more serious than many people realize.

    An article in the most recent issue of the American Journal of Play details not only how much children's play time has declined, but how this lack of play affects emotional development, leading to the rise of anxiety, depression, and problems of attention and self control. “Since about 1955, children's free play has been continually declining, at least partly because adults have applied ever-increasing control over children's activities.” says the author Peter Gray, Ph. D, Professor of Psychology at Boston College.

    We can describe the unstructured freely-chosen play as a testing ground for life. It provides critical life experiences without which young children cannot develop into confident and competent adults. So kids need more of it, not less. Because play is how young children learn important social and emotional skills such as sharing, cooperating, communicating, and empathizing. It helps them develop fit bodies, strong minds, and brave hearts, so they can take on new challenges and risky situations.

    Gray's article is meant to serve as a wake-up call regarding the effects of lost play. We must know that lack of childhood free play time is a huge loss that must be paid attention to for the sake of our children and society. But parents who keep a lookout over and disturb their children's play are a big part of the problem. It is hard to find groups of children outdoors at all, and, if you do find them, they are likely to be wearing school uniforms and following the directions of coaches while their parents dutifully watch and cheer.

    Actually, when children are in charge of their own play, it provides a foundation for their future mental health as older children and adults. Play gives children a chance to find and develop a connection to their own self-identified and self-guided interest. It is through play that children first learn to make decisions, solve problems, improve self-control, and follow rules. Play helps children make friends and learn to get along with each other as equals. Most importantly, play is a source of happiness.

When parents realize the major role that free play can take in the development of emotionally healthy children and adults, they may wish to reassess the priorities ruling their children's lives. The needs for childcare, academic and athletic success and children's safety is important. But perhaps parents can begin to identify small changes——such as openings in the schedule, backing off from quite so many supervised (有监督的) activities, and possibly slightly less keeping watch on the playground that would start the slow returning to the direction of free, imaginative-directed play.

    In the early decades of the United States, the agrarian(土地的) movement promoted the farmer as society's hero. In the minds of agrarian thinkers and writers, the farmer was a person on whose well-being the health of the new country depended. The period between the Revolution, which ended in 1783, and the Civil War, which ended in 1865, was the age of the farmer in the United States. Agrarian philosophers, represented most eloquently by Thomas Jefferson, celebrated farmers extravagantly for their supposed centrality in a good society, their political virtue, and their Superior morality. And virtually all policy makers, whether they subscribed to the tenets of the philosophy held by Jefferson or not, recognized agriculture as the key component of the American economy. Consequently, government at all levels worked to encourage farmers as a social group and agriculture as economic enterprise.

    Both the national and state governments developed transportation infrastructure, building canals, roads, bridges, and railroads, deepening harbors, and removing obstructions from navigable streams. The national government imported plant and animal varieties and launched exploring expeditions into prospective farmlands in the West. In addition, government trade policies facilitated the exporting of agricultural products.

    For their part, farmers seemed to meet the social expectations agrarian philosophers had for them, as their broader horizons and greater self-respect, both products of the Revolution, were reflected to some degree in their behavior. Farmers seemed to become more scientific, joining agricultural societies and reading the farm newspapers that sprang up throughout the country. They began using improved implements, tried new crops and pure animal breeds, and became more receptive to modern theories of soil improvement.

    They also responded to inducements by national and state governments. Farmers streamed to the West, filling frontier lands with stunning rapidity. But farmers responded less to the expectations of agrarians and government inducements than to growing market opportunities. European demand for food from the United States seemed insatiable. War, industrialization, and urbanization all kept demand high in Europe. United States cities and industries grew as well; even industries not directly related to farming thrived because of the market, money, and labor that agriculture provided.

    Josh Katz works at the New York Times. His common job is to use information to tell interesting stories. In December 2013, Katz built a quiz on the Times website. It asked people about the words they used to describe things and events. It also asked how they pronounced common words. The quiz then used people's answers to decide where in the United States they were from.

    The quiz got more than 350, 000 results. Katz turned the results into a book. In Speaking American, he studies regional differences in how Americans talk.

"A lot of people's language shows who they are and where they are from, in a very personal way", Katz said.

Katz says people are often surprised to learn that the way they talk can show where they grew up. Most Americans don't realize they use regionalisms — or words and phrases specific to a particular part of the country. But just about everyone does. Almost every major U.S. city has a few unique terms. For example, in Philadelphia, Pennsylvania, the night before Halloween is known as Mischief Night. Anyone who calls it that is likely to be connected to the city.

    Katz himself was surprised by how many common words are regional. "There are a lot of words I use that I just thought were standard words," he says. "Then I found out some of these words were actually a product of my upbringing."

    For example, he says, "I thought everyone said 'sneakers' (运动鞋) and not 'tennis shoes'." But it turns out "sneakers" is connected mostly to the Northeast. That's where Katz is from.

    Some scholars think that language in the U.S. is growing more homogeneous (同类的). But Katz disagrees. "These regional differences are here to stay." he says.

    Not only are people still using common regionalisms, but there are new ones appearing all the time, according to Katz. There's no way to predict how language will change in the future. But Katz sees more changes coming. "The only sure thing about language is that it's going to keep moving." he says.