Energy goes from one plant or animal to another. A food chain shows how this energy moves. Each time an animal gets eaten, its energy is passed onto the animal that eats it. The food chain is very important because it keeps the balance of nature. If one part of the food chain disappears, it can affect all the other plants and animals. Any threat to the food chain is a threat to the environment's biodiversit(生物多样性). The food chain helps keep animal populations in balance. However, if something happens to increase or decrease one of the links in the food chain, that balance is broken. If one animal becomes endangered, it puts all the animals above it at risk.

    Some of the threats are natural, such as wildfires, hurricanes, tornados, floods and so on. But the biggest threats to the food chain come from you and me. These threats include overhunting, overfishing, logging, farming, development, pollution, etc. The food chain is endangered anywhere humans have had an effect on the natural environment.

    A recent study shows that the overfishing of large sharks is damaging the food chain along the US Atlantic coast. Canadian and American scientists say sharks are being killed in great numbers for their meat and fins(鳍). Now, not enough sharks are around to eat the cownose(牛鼻) ray. The ray's population has increased and they have eaten up the shellfish to the point where it has hurt commercial(商业的) fishing.

    Many of us disturb the natural environment in our own backyards. It's up to us to take care of the environment and try not to disrupt the natural food chain. If we don't act responsibly, animals will start disappearing.

    You get anxious if there's no wi-fi in the hotel or mobile phone signal up the mountain. You feel upset if your phone is getting low on power, and you secretly worry things will go wrong at work if you're not there. All these can be called “always on” stress caused by smart phone addiction.

    For some people, smart phones have liberated them from the nine-to-five work. Flexible working has given them more autonomy（自主权）in their working lives and enabled them to spend more time with their friends and families. For many others though, smart phones have become tyrants（暴君）in their pockets, never allowing them to turn them off, relax and recharge their batteries.

    Pittsburgh-based developer Kevin Holesh was worried about how much he was ignoring his family and friends in favour of his iPhone. So he developed an app — Moment — to monitor his usage. The app enables users to see how much time they're spending on the device and set up warnings if the usage limits are breached（突破）. “Moment's goal is to promote balance in your life,” his website explains. “Some time on your phone, some time off it enjoying your loving family and friends around you.”

    Dr. Christine Grant, an occupational（职业的）psychologist at Coventry University, said, “The effects of this 'always on' culture are that your mind is never resting, and you're not giving your body time to recover, so you're always stressed. And the more tired and stressed we get, the more mistakes we make. Physical and mental health can suffer.”

    And as the number of connected smart phones is increasing, so is the amount of data. This is leading to a sort of decision paralysis（瘫痪）and is creating more stress in the workplace because people have to receive a broader range of data and communications which are often difficult to manage. “It actually makes it more difficult to make decisions and many do less because they're controlled by it all and fell they can never escape the office,” said Dr. Christine Grant.

    You probably know who Hillary Diane Rodham Clinton is, but you may not have heard of Margaret Munnerlyn Mitchell if you are not interested in foreign literature. Of the outstanding ladies listed below, who is your favorite?

    Jane Austen (16 December, 1775-18 July, 1817)

    Jane Austen, a famous English writer, was born at Steventon, Hampshire. She began writing early in life, although the prejudices (偏见) of her times forced her to have her books published anonymously (匿名).

    She wrote many books of romantic fiction about the gentry (贵族). Her works made her one of the great masters of the English novel. Only four of her novels were printed while she was alive. They were Sense and Sensibility (1811), Pride and Prejudice (1813), Mansfield Park (1814) and (1816).

    Charlotte Bronte (21 April, 1816-31 March, 1855)

    She first published her works, including Jane Eyre, under the false name of Currer Bell. Her first novel, The Professor, was rejected by many publishers. It was not printed until 1857. She is famous for her novel Jane Eyre (1847), which was very popular when it was printed. Jane Eyre was a strong story of a plain, brave, clever woman struggling with her passions, reasons, and social condition.

    Margaret Munnerlyn Mitchell (8 November, 1900-16 August, 1949)

    She was an American author and journalist, a lifelong resident and native of Atlanta, Georgia. One novel by Mitchell was published during her lifetime, the American Civil-War-Era novel, Gone with the wind, for which she won the National Book Award for Most Distinguished Novel of 1936 and the Pulitzer Prize for Fiction in 1937. In more recent years, a collection of Mitchell's girlhood writings and a novel she wrote as a teenager, Lost Laysen, have been published. A collection of articles written by Mitchell for The Atlanta Journal was republished in book form.

    Starting Cycling

    We have two services designed to give people the confidence and knowledge to cycle successfully.

    Lessons

    All our instructors have been trained to National Standards level of “Bikeability”. This means you will be trained to a standard consistent across the whole country.

    There are 3 levels of skills to progress through. Children would start with levels 1 & 2, progressing from the playground or park to cycle on less busy local roads. Teenager and adult beginners can also learn levels 1 & 2 in an off-road and quiet environment.

    Confident teenagers and adults can broaden their skills by learning level 3, using multi-lane (多道) roads and larger roundabouts (环岛). We provide both a complete package of lessons for the beginner or individual lessons tailored to the client. You can ride a bike but don't feel confident about right turns on multi-lane roads. Whatever the need we can address and practice until perfect!

    Everyone can be taught to ride a bike!

    We train both adults and children.

    We cover London Zones 1 & 2

    The cost is ￡30 per hour.

    Guided Ride

    We know that riding on the roads in London can be scary, and if you have to navigate (确定行车路线) as well it can become a real hard task! The Guided Ride service takes all the stress out of it for you by providing the following:

    Route planned in advance to suit your skill level. Route map provided to you.

    Cycle and equipment checked. We will teach you a simple method to check basic roadworthiness (车辆性能) of your bike that you can perform on a weekly basis.

    Route discussed and focus given to any areas requiring special attention.

    Cycle along with the instructor close behind. Here the traffic can be controlled by the instructor and rider observed.

    Occasionally stopping to discuss events.

    We currently cover London Zones 1 & 2. Please contact us if your requirements are outside of these areas.

    Cost ￡30

    Nola (August 21, 1974-November 22, 2015)was a northern white rhino(犀牛) who lived at the San Diego Zoo Safari Park near Escondido, California. At her death, she was one of only four remaining northern white rhinos in the world. The other three lived in Kenya. World Rhino Day, held on September 2, is to raise awareness(意识) of the less than 30, 000 other rhinos left on Earth.

    "Rhinos need our help today, not tomorrow," Nola's lead keeper Jane Kennedy said. "Last year we lost over 1, 200 rhinos just in South Africa. If we continue to lose more than 1, 000 rhinos a year, in 10 to 20years all the rhinos on the planet will be gone. "

    "Unfortunately, most animals are in danger of dying out because of humans," Kennedy says. "Humans have either poached animals, or because there are over seven billion of us, we've taken up too much of the world's resources". Poachers illegally hunt rhinos for their horns. They sell the horns for thousands of dollars per pound, to be used for art, jewelry, and decorations. Experts believe that one rhino is poached every eight hours.

    In 1975, the San Diego Zoo Institute for Conservation Research started the Frozen Zoo, a program through which researchers have collected cell (细胞) samples from more than 8, 000 different types of animals, including the northern white rhino. Scientists hope that by studying the rhino cells, they will get greater understanding of it, and will find ways to increase its numbers.

    Jane Kennedy describes World Rhino Day as "a celebration of rhinos along with an awareness campaign(活动)for everybody across the world to know that rhinos need our help. "At the San Diego Zoo, children and adults are welcome to visit and speak with zookeepers to learn about rhinos. But you don't have to live in San Diego to celebrate World Rhino Day. It is observed around the world, with zoos and wildlife parks holding special events and programs to teach people about rhinos, and enable them to see the animals up close. For more information, go to www. worldrhinoday.org.

    About three decades ago, China was known as the "Bicycle Kingdom".But the two­wheeled transport's popularity began to fade, with many bikes soon replaced by their fuel­powered competitors.

    But recent months have seen a renaissance of the bike across China, with an increasing number of people choosing cycling instead of driving to schools, to workplaces or to do sightseeing. The introduction of bike­sharing schemes, first developed by new companies like Ofo and Mobike, has brought the trend to a new level. According to data from iResearch Consulting Group, the first week of this year saw 5.85 million active users of Mobike while Ofo had 1.4 million active users.

    People can unlock the shared bikes by simply using their smartphones. The bikes are equipped with GPS and can be left anywhere in public places for the next user. They're popular among many Chinese people as they provide an effective answer to the "last mile" problem, which refers to a person's final journey. "In places where the subway doesn't reach and where it's difficult to change from one kind of transport to another, it's so easy to get where you want to go with Mobike," Hu Hong, 29, said. She rides a bike to work.

    However, the schemes have also led to problems such as illegal parking, vandalism (故意破坏) and theft. "Bike­sharing is a greener method of transportation and provides a user­friendly experience," said Liu Xiaoming, Vice­Minister of Transport. "But it's a combination of online and offline business. Operators are usually strong in online services, but lack offline business experience."

    In fact, these problems are also shared by bike­sharing schemes abroad. Set up in 2007, Vélib is a large­scale public bike sharing system in Paris. By October, 2009, a large number of Vélib's initial bikes had to be replaced due to vandalism or theft. Bikes were found hanging from lampposts (街灯柱) or thrown into the Seine River.