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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    Last night's meteor (流星) shower left many people in the community dissatisfied and demanding answers. According to Gabe Rothschild, Emerald Valley's mayor, people gathered in the suburbs of the city, carrying heavy telescopes, expecting to watch the brightly burning meteors passing through the sky. What they found instead was a sky so brightened by the city's lights that it darkened the light of the meteors passing overhead.

     “My family was so frustrated,” admitted town resident Duane Cosby, “We wanted to make this an unforgettable family outing, but it turned out to be a huge disappointment.”

    Astronomers—scientists who study stars and planets—have been complaining about this problem for decades. They say that light pollution prevents them from seeing objects in the sky that they could see quite easily in the past. They call on people and the government to take measures to fight against it.

    There is yet a population besides professional and amateur star observers that suffers even more from light pollution. This population consists of birds, bats, frogs, snakes, etc. For example, outdoor lighting severely affects migrating (迁徙的) birds. According to the International Dark-Sky Association, “100 million birds a year throughout North America die in crashes with lighted buildings and towers.”

    Countless more animal casualties (伤亡) result from the use of artificial lighting. Clearly, people enjoy the benefits of lighting their evenings. But some scientists think it can be harmful for humans, too. They worry that exposure to light while sleeping can increase a person's chances of getting cancer.

    Emerald Valley is only one community that is becoming aware of the negative effects of light pollution. For years, Flagstaff, Arizona, has enforced lighting regulations in its city in order to assist astronomers at the Lowell Observatory. Similar efforts have been made worldwide, and a movement is underway to remind us to turn off lights when we are not using them, so that other creatures can share the night.

    ELECTRICITY IS AT THE CORE OF MODERN LIFE. DESPITE THIS, THE FULL STORY OF THIS REVOLUTIONARY FORCE HAS REMAINED UNTOLD—UNTIL NOW.

    Simply Electrifying offers the comprehensive story of one of mankind's most important journeys: from a time when only a few could even imagine a world with electricity to today when, for most of us, a world without electricity would be unimaginable.

    Since the birth of the modern science of electricity 265 years ago, mankind has built an impressive structure to produce, deliver, and use electricity, thanks to a combination of pioneering science, innovative technology, wise business strategy, and pervasive (到处存在的)economic and environmental regulation.

    Simply Electrifying brings to life the stories of the people that made it all possible—from early pathfinders like Benjamin Franklin, Michael Faraday, James Clerk Maxwell, and Albert Einstein to innovators such as Samuel Morse, Thomas Edison, George Westinghouse, and Nikola Tesla. In modern times, business strategists and economic and environmental regulation driven by many, including President Franklin D. Roosevelt, Rachel Carson, and even President Barack Obama, have shaped how we use and understand electricity in crucial ways. Today, Elon Musk and others are on the edge of again changing the way we think about and interact with it.

    Simply Electrifying is painstakingly researched and beautifully written, showing us how both profit-makers and policy-makers must use a wide-angle lens to truly understand the past and predict the future.

    By now, you've probably been warned that a robot is coming for your job. But rather than repeat the warning, I've decided to throw down a challenge: man against machine.

    Start with the task we're doing right now: communicating in fluent human. We're sharing abstract ideas through words that we choose with an understanding of their slight difference and impact. We don't just speak in human; we speak as humans. A robot who says that science is fun is delivering a line (念一句话). A human who says that science is fun is telling you something important about being alive.

    Here's another inbuilt advantage we take for granted: as humans we are limited by design. We are bound in time: we die. We are bound in space: we can't be in more than one place at a time. That means when I speak to an audience, I am giving them something special. It's a custom-made, one-off, 100% robot-free delivery, from today's one-and-only Australian Chief Scientist.

    True, I now come in digital versions, through Twitter and Facebook and other platforms, but the availability of those tools hasn't stopped people from inviting me to speak in person. Digital Alan seems to increase the appetite for human Alan, just as Spotify (a digital music service) can increase the demand for a musician's live performances.

    Thanks to technology, many goods and services are cheaper, better and more accessible than ever before. We like our mass-produced bread, and our on-tap lectures and our automated FitBit advice. But automation hasn't killed the artisan bakery (面包店). Online courses haven't killed the booming, alongside their machine equivalents.

    Here's a third argument for the win. We humans have learned the habit of civilization. Let me explain this point by a story. A few years go, some researchers set out to study the way the people interact with robots. They sent out a small robot to patrol (巡逻) the local mall. That robot had a terrible time, and the villains of the story were children. They kicked him, bullied him, and smacked (掌击) him in the head.

    The point is not that the children were violent. The point is that the adults were not. They restrained whatever primitive impulse (冲动) they might have felt in childhood to smack something smaller and weaker in the head, because they had absorbed the habit of living together. We call it civilization. If we want artificial intelligence for the people, we'll need every bit of that civilizing instinct.

    Together, these points suggest to me that humanity has a powerful competitive edge. We can coexist with our increasingly capable machines and we can make space for the full breadth of human talents to flourish.

    I admire my father for as long as I can remember. I loved the way he treated people with such respect and kindness.

    On Sundays we usually took the bus into Manhattan, where we would do interesting things, like riding the Circle Line. He would point out every landmark and tell us the history behind it. He loved to take us on the subway to Nathan's in Coney Island. Once there, he would give my sister and me each a five-dollar bill and then he would enjoy himself for the afternoon with his newspapers.

    In 1968, we went to see the movie “Oliver”, a Charles Dickens' classic story of a young orphan(孤儿) boy called Oliver. On the way home from the theater that afternoon he told us how he was raised in an orphanage(孤儿院) in New York after both of his parents died. He told us the nuns(修女) were wonderful to him and loved him like a mother would. As he grew older, he was placed in a few foster(寄养) families before he joined the Army.

    When we were teenagers, he still took us out each weekend and he would ask us to invite specific friends to join us and he would pay for them. We often went to Yankee Stadium to watch the baseball game and he bought us tickets in the least expensive seats. To keep the cost down, he waited for us in the car where he read his newspapers and then took a nap(小睡).

    He was always happy and appreciated everything he had. He loved his two little girls and later his two granddaughters. He gave so much, yet he had so little. He thought he was the richest man in the world.

    In the U. S. state of Washington, a road called Interstate(州际公路；州际的)90 cuts through a wild mountainous area to reach the city of Seattle. For the area's many kinds of animals, busy high- way greatly limits their movements. Animals need to move to find food, to find mates, to find new places to live as their populations expand or just when conditions change, like a fire breaks out. Crossing I-90 – as the road is called – is a risky but sometimes necessary act. But soon, animals will have a safer choice. They will be able to go above it.

    To help the animals, the state is finishing work on its largest - ever wildlife bridge. The 11-meter-tall, 20 - meter - wide bridge begins in the forest. It forms two arches above the highway, one for each direction of traffic. Workers are adding fencing anti plants to help guide the animals across the bridge, Two-meter-thick walls will help block noise from vehicles below. Scientists chose the area because it is within a natural migration(迁徙)path for some animals.

    The I -90 bridge is part of a growing number of wildlife crossings across the United States. Some are fences, some are overland bridges，and some are underpasses. They all aim to keep drivers and animals away from each other.

    A U. S. Transportation Department study found crashes between animals and humans rose year by year. The accidents made up about 5 percent of all crashes nationally, and cost the economy (经济)about ＄8 billion. Such costs come from car repaid, emergency room visits and removal of the dead animals on roads. Collisions between animals and drivers are rarely deadly to people. But they are often deadly to wildlife. The study also found that 21 endangered or threatened species in the U.S. are affected by vehicle hits. Bridges, underpasses and fencing reduce I he area's animal - driver collisions by 80 percent.

    Most of the wildlife bridges are in western states. Many other areas also need such paths. But finding money for more crossings is "the- number - one problem". Patty Garvey — Darda of the U. S. Forest Service has worked on the I - 90 crossing from the start of the project. She says the $ 6 - million bridge will one day pay for itself because the highway will not have to be fully or partly closed each time a large animal is struck. "If you shut clown Interstate 90, you shut down interstate trade." she adds.