When you choose to send one of our free E-cards, you save paper and give friends and family the opportunity to enjoy the wonder of nature.

    Celebrate the beauty of our natural world and send an E-card to friends and family who care about protecting our planet. Feel free to set your E-card to arrive on any day you please.

    Looking for something to do besides sending an E-card?

    Check out our Everyday Environmentalist page with eco-tips on how to live greener, and become an e-member of our free global online community or calculate(计算) your carbon footprint. You can even upload your photos to our site and your photo may be featured in an E-card next year!

    In a paper published in the journey Science Advance, researchers describe how Matabele ants, a species of large ant known for attacking termite colonies (白蚁群落), will, after the battle, pick up injured fellow soldiers and carry them back to the nest where they can recover.

    The paper is the latest in a growing body of research that this form of helping behavior, previously observed in some mammals and birds, may not require complex emotion, and may, therefore, be far more widespread in nature than previously thought.

    “Here we have an example of an individual saving another individual,” says lead researcher Erik Frank who conducted the research. “We can be quite certain that the ants don't know why they are doing what they are doing.”

    It's a behavior that pays off for the colony. Our classic conception of worker ants is that they are essentially abandoned, but Mr. Frank and his colleagues calculated that the practice of rescuing nest mates results in a colony size that is a 28.7 percent larger than it would be had the ants left their fellow soldiers for dead.

    “These injured ants are able to recover from their injuries, ” says Frank. “They are essential for the safety and the betterment of the colony. ”

    When a Matabele ant is injured, as often happens during battles with termites, its body will give off two smelly chemicals that tell other ants to carry it back to the nest. Indeed, the researchers found that using these chemicals to seek help from uninjured ants will effectively activate the rescue behavior, supporting their theory that the ants were acting on pure instinct(本能), not more complex emotions.

    “The more we study rescue behavior in ants and other animals, the more we are going to realize that it's not just limited to the species we've observed so far, ” says Karen Hollis, a professor at Mount Holyoke College, mentioning studies that found that dolphins help other injured dolphins to the surface for air, capuchin monkeys defend each other during intergroup battles, and rats free other rats that are trapped.

    Every year on April 1, April Fools' Day is celebrated in many countries around the world. In France, it's called "Poisson d' Avril" or "Fish of April." In Scotland, the holiday is often called "Gowkie Day." In Iraq, the holiday is called Kithbet Neesan or "April Lie."

    History experts say people have celebrated April Fools' Day for a long time. Some believe the tradition comes from the ancient Romans more than two thousand years ago. It was a day of playing games and pretending to be someone else.

    Others say the day for fooling began in France in 1564, when King Charles changed the yearly calendar. He moved New Year's Day from April 1 to January 1. Many people did not know about the change because of communication problems back then. Some people continued to celebrate New Year's Day on April 1. Other people called them April Fools and played jokes on them.

    In the United States, April Fools' Day is just a day of joking and playing tricks on friends. These kinds of jokes are also called pranks. These jokes typically end in the prankster shouting "April Fools'!"

    Simple pranks, like telling a friend a funny lie or making prank phone calls, are still common. But, major companies also get in on April Fools' Day fun in a much bigger way. A few years ago, on April 1, Starbucks announced it was introducing new coffee cup sizes -- Plenta and Micra. The very large cups, bigger than a human head, remained useful for customers even after finishing all that coffee. According to Starbucks, the cups could be used as a rain hat, a pot for plants, or a lampshade.

    It did not take long for customers to catch on to the prank! More and more people use social media or smart phone apps to play pranks on their friends on April Fools' Day. One very annoying smart phone app, Cat Facts, sends funny facts about cats to your friends' phones, every day.

    San Francisco has long been a favorite place for travelers who are ready to learn languages. The mild (温和的) year-round climate, shops and restaurants, bars and night life, and some of the most beautiful scenery attract many visitors to this relaxing and welcoming city. Students are sure to find the San Francisco Bay Area a fun, safe and friendly place to live and study. This is the most important.

    English School in San Francisco lies in the heart of the city. It is one of the best San Francisco English language schools. You can see views of the city from your classroom! Many buses stop less than a five-minute walk from the school, which is also just a two-minute walk from the famous Union Square, San Francisco Shopping Centre, the Financial District, Yerba Buena Gardens and the Museum of Modern Art. The school is minutes away from the cable cars (缆车) to Chinatown and Fisherman's Wharf.

    San Francisco is a great place to study English and learn about American culture, offering excellent opportunities in sports, entertainment and arts. The city borders (毗邻) excellent beaches, and you can sail or surf all year round.

    San Francisco has more restaurants than any other city in the US, and is the home of many theaters, music and dance companies, as well as museums. Just walking through many areas of San Francisco, you are certain to find something wonderful.

    Teachers' Day is, interestingly, not celebrated on the same day all over the world. In some countries it is marked by a holiday, in others it is a working day.

    International Teachers' Day is celebrated on October 5. Being held ever since 1994, it is in honor of teachers' organizations worldwide. Its aim is to encourage supports for teachers and to meet the needs of students.

    China   In 1939, Teachers' Day was set for August 27, Confucius' birthday. In1951, the celebration was stopped. However, it was founded again in 1985, and the day was changed to September 10.

    India   Teachers' Day is celebrated on September 5 in honour of Dr. Sarvepalli Radhakrishnan, the second president of India, whose birthday falls on that day.

    Russia   In Russia, Teachers' Day was celebrated on the first Sunday of October between 1965 and 1994. Since 1994, the day is observed on the October 5, just the same day as World Teachers Day.

    The US   In the US, Teachers' Day is non-official holiday. It is celebrated on the Tuesday of the first full week of May. A number of activities are organized in schools to honor teachers. The celebrations can continue for the whole week of May.

    Thailand   In Thailand, National Teachers' Day is celebrated every year on January 16. The first Teachers' Day was held in 1957. The day is a holiday in schools.

    People say that text messages and e-mails lack emotion compared to phone or face-to-face conversations. But one thing seems to improve it – the emoticon(表情符).

    These little symbols – whether it's a wink(眨眼); -), a smiley : -) or a sad face : -) - always add a little something to whatever you are sending out, making it more expressive than cold words on a screen.

    To be sure, emoticons have changed the way that we communicate with each other. But there is more: a new study found that they are even changing how our brains work – we now react to emoticons in the same way as we would to real human faces, reported Live Science.

    It's actually amazing when you start to think about it: what an emoticon consists of is simply three punctuation marks(标点符号) – on their own, they carry no meaning as a pair of eyes, a nose or a mouth, but after they were first put together as symbols for faces in 1982, they began to appear more and more in our written materials.

    Owen Churches, a scientist at Flinders University in Australia, wanted to find out what people see in emoticons that make them so popular. So he showed 20 participants images of real faces, a smiley emoticon and a series of meaningless characters while their brain activities were monitored.

    Previous studies have already shown that our brains process human faces differently than they do other objects – they analyze the position of the mouth relative to the nose and the eyes to “read” for emotions. As a result, certain parts of our brain, such as the occipital-temporal cortex, are activated(激活).

    When Churches compared participants' brain activities, he was surprised to find that the brain areas that were activated when people looked at smiley emoticons were the same as when they were shown pictures of real faces.

    According to Churches, this is a good example of how culture is shaping our brains. “Emoticons are a new form of language that we're producing,” Churches told ABC Science. “Before 1982 there would be no reason that ':-)' would activate face-sensitive areas of the cortex, but now it does because we've learnt that this represents a face.”

    Next time you chat with your friends online, try to use emoticons where they are needed. It'll be almost like you're smiling or winking at them yourself.