Alpacas(羊驼) are members of the camel family, having lived in South America for thousands of years. Their fur gives the animals a teddy bear_like appearance. Alpacas are too small to be used as animals of burden but are valued only for their fur. Generally, their lifespan is around 15 to 20 years.

    Alpacas are social animals that live in family groups made up of a male, females and their young. They are gentle, elegant, curious, intelligent and observant. They are safe and pleasant to be around, moving gracefully and slowly around the field, and are therefore unlikely to run into or over anyone, even small children. Occasionally, an alpaca will spit snd kick, but the soft padded(有爪垫的) feet usually do little more than just“get your attention”.

    Because these animals are environmentally friendly and need so little grass and food, you can usually raise from two to eight alpacas on an acre of land with grass or hay. A single, 60 pound bale(大捆) of hay can generally feed a group of about 20 alpacas for one day. Alpacas also require access to plenty of fresh water to drink.

    Alpaca fur is used for making knittedd and woven(编织) items, just as sheep's wool is. These items include blankets, sweaters, hats, gloves, scarves, a wide variety of textiles(针织品) in South America, and sweaters, socks, coats and bedding in other parts of the world. The fur comes in more than 52 natural colors as classified in Peru, 12 as classified in Australia and 16 as classified in the United States.

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    Try this: For an entire day, forget about the clock. Eat when you're hungry and sleep when you're tired. What do you think will happen?

    You may be surprised to find that your day is much like most other days. You'll probably get hungry when you normally eat and tired when you normally sleep. Even though you don't know what time it is, your body does. These patterns of daily life are called circadian rhythms(生理节奏), and they are more than just habits. Inside our bodies are several clocklike systems that follow a roughly 24-hour cycle. Throughout the day and night, our inner clocks direct changes in temperature, body chemicals, hunger, sleepiness and more.

    Everyone's rhythms are different, which is why you might like to stay up late while your sister always wants to go to bed early. But on the whole, everyone is programmed to feel tired at night and energetic during the day. Learning about our body clocks may help scientists understand why problems arise when we act out of step with our circadian rhythms. For example, traveling across time zones can make people wake up in the middle of the night. Regularly staying up late can make kids do worse in tests.

    "There is a growing sense that when we eat and when we sleep are important parts of how healthy we are," says Steven Shea, director of the Sleep Disorders Program at Brigham and Women's Hospital in Boston.

    One way to learn about how our body clocks tick is to mess them up and see what happens. That's what neurologist(神经病学家)Frank Scheer and his workmates did in a recent study. Staying up night after night, their studies suggest, could make kids extra hungry and more likely to gain weight. And regularly sleeping too little, Scheer says, may be one cause of the recent increase in childhood obesity.

    A newspaper reporter's job can be very interesting. He meets all types of people and lives quite a busy life. He is on the rush for news all the time, then after several years he may get a desk job, and life becomes a bit more settled. Let's look at his work a little more closely. In a day he may have to interview the prime minister of a foreign country, and the next day he may be writing about a football match. Sometimes he may be so busy that he has hardly any time to sleep. And at other times he may go on for days looking out for news materials yet return empty-handed.

    In the beginning, a reporter has to cover a very wide field. After the early years he becomes more specialized in his work. For example, he may finally be asked to write only on court cases or politics or sports. Some reporters may become so specialized that they are asked only to write on a special thing: horse racing, for example. In most newspaper houses there is at least one special racing correspondent. Some newspapers have book reviews. Their job is delightful. They read the latest book and then write reviews on the ones they like. Then there are those who write on films, so they get to see them even before they are shown in the cinema. How lucky, you would say!

    A reporter's job can also be very dangerous. A number of them have died rushing from one assignment to another, and if there is a flood or a riot(暴) they may get hurt or even be killed. Three years ago there was a reporter whose camera was smashed by a group of men, because they were angry with him for taking their picture. Dangerous or not, one thing is certain, and that is, their job is never dull!

Seeds on Ice

    Close to the North Pole, remote and rocky Plateau Mountain in the Norwegian archipelago of Svalbard seems an unlikely spot for any global effort to safeguard agriculture. In this cold and deserted environment, no grains, no gardens, no trees can grow. Yet at the end of a 130-meter-long tunnel cut out of solid stone is a room filled with humanity's most precious treasure, the largest and most diverse seed collection—more than a half-billion seeds.

    A quiet rescue mission is under way. With growing evidence that unchecked climate change-will seriously affect food production and threaten the diversity （多样性） of crops around the world, the Svalbard Global Seed Vault （地窖） represents a major step towards ensuring the preservation （贮藏） of hundreds of thousands of crop varieties. This is a seed collection, but more importantly, it is a collection of the traits found within the seeds: the genes that give one variety resistance to a particular pest and another variety tolerance for hot, dry weather.

    Few people will ever see or come into contact with the contents of this vault. In sealed boxes, behind multiple locked doors, monitored by electronic security systems, enveloped in below—zero temperatures, and surrounded by tons of rock, hundreds of millions of seeds are protected in their mountain fortress. Frozen in such conditions inside the mountain, seeds of most major crops will remain viable for hundreds of years, or longer. Seeds of some are capable of retaining （保留） their ability to grow for thousands of years.

    Everyone can look back now and say that the Seed Vault was a good and obvious idea, and that of course the Norwegian government should have approved and funded it. But back in 2004, when the Seed Vault was proposed, it was viewed as a crazy, impractical, and expensive idea.

    We knew that nothing would provide a definite guarantee. But we were tired, fed up, and frankly scared of the steady, greater losses of crop diversity. The Seed Vault was built by optimists who wanted to do something to preserve options so that humanity and its crops might be better prepared for change. If it simply resupplied seed gene banks with samples those gene banks had lost, this would repay our efforts.

    The Seed Vault is about hope and commitment-about what can be done if countries come together and work cooperatively to accomplish something significant, long-lasting, and worthy of who we are and wish to be.

    On Nov. 24, near Yellowstone's northeast entrance, Spitfire, a female grey wolf, was shot and killed by a hunter as she approached a group of cottages.

    "It was a legal harvest," Abby Nelson, a wolf management specialist said. "The facts are obviously a little bit harder for people to bear, but that pack has showed signs of habituation. They just stand there and have no fear. Wolf hunters can easily pick the one they want."

    The carefree relation that some Yellowstone wolves have built with humans is reportedly attractive for hunters who look for an easy kill.

    In the overnight, yet another famous Yellowstone wolf met a violent end outside the park, officials are actively rethinking how to manage wildlife habituation.

    Smith, a wolf biologist for Yellowstone, says, "Now we're thinking of pounding them," Park officials might use fireworks, and paintball or beanbag guns when they approach humans in the park. "If you get close to people, you're going to get attacked."

    If you think this sounds cruel, you're not alone. Seeing these creatures from the roads that wind through the park not only allows tourists to witness something amazing, but also to reconnect with nature in a way that is better than any conservation campaign. But there's a growing sense that the present policy of doing nothing isn't working; more wolves will unnecessarily die and the broken record of hunters scoring easy kills will go on.

    As Smith adds, urging people to keep wolves wild when meeting them halfway is a big ask. Still, he's hopeful to preserve the world's best place to observe free­ranging wolves; it's a policy change that tourists can be involved in.

    "... perhaps Spitfire's death will accomplish some good, and we'll all come together to do a better job on managing crowds and roads and wolves in Yellowstone, " Smith said.

It's normal to long for the taste of potato chips or a cheese-covered pizza. Even though they're full of calories, eating them occasionally won't do much harm. However, according to the new numbers, young people are becoming more gluttonous. The BBC's Good Food Nation Survey showed that on average, 16 to 20-year-olds ate fast food at least twice a day in the UK. So what's behind this fast food binge (狂热)?

WebMD, an online publisher of news and information of human health and well-being, surveyed nearly 600 teenagers and adults in the United States. They found that the most common reason was our busy lifestyle. More than 92.3 percent of respondents said they were too busy to cook. Many find it challenging to balance work and life, and the convenience of fast food meets their needs. Fast food is readily available in corner stores and vending machines (自动售货机). Remember those instant noodle cups from the supermarket? They're ready in minutes, and you can store them at home for a long time.

But many people think this trend does no good. Sarah Toule, head of health information at World Cancer Research Fund, told the BBC: "It's frightening that people, especially younger generations, are eating so much fast food loaded with fat, sugar and salt, but offers little nutritional value."

She added, "Especially high in calories, fast food leads to unhealthy weight gain — which in turn increases the risk of 11 cancers later in life."

So what is the right thing to do? Toule suggested that young people should prepare meals in advance and learn to include the different food groups in their diets.