One day an ant was drinking at a small stream and fell in. She made desperate efforts to reach the side, but made no progress at all. The poor ant almost exhausted was still bravely doing her best when a dove saw her. Moved with pity, the bird threw her a blade of grass, which supported her like a raft, and thus the ant reached the bank again. While she was resting and drying herself in the grass, she heard a man come near. He was walking along barefooted with a gun in his hand. As soon as he saw the dove, he wished to kill it. He would certainly have done so, but the ant bit him in the foot just as he raised his gun to fire. He stopped to see what had bit him, and the dove immediately flew away. It was an animal much weaker and smaller than herself that had saved her life.

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    A large body of research has been developed in recent years to explain many aspects of willpower. Most of the researchers exploring self-control do so with an obvious goal in mind: How can willpower be strengthened? If willpower is truly a limited resource, as the research suggests, what can be done to make it stay strong?

    Avoiding temptation (诱惑）is an effective method for maintaining self-control, which is called the “out of sight, out of mind” principle. One recent study, for instance, found office workers are less attracted to candy in the desk drawer than that on top of their desks, in plain sight.

    The research suggesting that we possess a limited reservoir of self-control raises a troubling question. When we face too many temptations, are we to fail? Not necessarily. Researchers don't believe that one's willpower is ever completely exhausted. Rather, people appear to hold some willpower in reserve, saved for future demands. The right motivation allows us to tap into those reserves, allowing us to carry on even when our self-control strength has been run down. High motivation might help overcome weakened willpower—at least to a point.

    Willpower may also be made less vulnerable (脆弱) to being exhausted in the first place. Researchers who study self-control often describe it as being like a muscle that gets tired with heavy use. But there is another aspect to the muscle comparison, they say. While muscles become exhausted by exercise in the short term, they are strengthened by regular exercise in the long term. Similarly, regular practices of self-control may improve willpower strength.

    The evidence from willpower-exhaustion studies also suggests that making a list of resolutions on New Year's Eve is the worst possible approach» Being exhausted in one area can reduce willpower in other areas, so it makes more sense to focus on a single goal at a time. In other words, don't try to quit smoking, adopt a healthy diet and start a new exercise plan at the same time. Taking goals one by one is a better approach. Once a good habit is in place, Baumeister says, you'll no longer need to draw on your willpower to maintain the behavior. Eventually healthy habits will become routine, and won't require making decisions at all.

    Many questions about the nature of self-control remain to be answered by further research. Yet it seems likely that with clear goals, good self-monitoring and a little practice, you can train your willpower to stay strong in the face of temptation.

    In February, 2015, a South Korean woman was sleeping on the floor when her robot vacuum ate her hair, forcing her to call for emergency help. It surely isn't what Stephen Hawking warned us that intelligent devices “mean the end of the human race”. But it does highlight one of the unexpected dangers of inviting robots into our home.

    There are many examples of intelligent technology going bad, but more often than not, they involve cheating rather than physical danger. Meanwhile, increasing evidence suggests that we, especially children, tend to tell our deepest, darkest secrets to human robots. So how do we protect ourselves from giving-away code?

    Once you've invited a robot into your home, you need to manage your expectations. Movies and marketing may have told us to expect deep interaction with robots friends but we've still got a long way to go before they are as socially aware as described. Given the gulf between expectation and reality, it's important to avoid being tricked.

    The message is clear: as robots became increasingly connected to the internet, and able to respond to natural language, you need to especially cautious about figuring out who or what you are talking about.

    We also need to think about how information is being stored and shared when it comes to robots that can record our every move. Some recording devices may have been designed for entertainment but can easily be adapted for more dangerous purposes. Take Nixie, the wearable camera that can fly off your wrist at a moment's notice and take shots around you in the air. It doesn't take much imagination to see how such technology could be taken advantage of.

    If the technology around us is able to record and process speech, images and movement, or listen secretly to us, what will happen to that information? Where will it be stored? Who will have access?

    So, what is the safest way to welcome robots into our homes, public spaces, and social lives? We should be cautiously optimistic that intelligent machines could become enriching companions, while acknowledging that we need to determine strict boundaries for robots. There should be someone to turn to should your robot commit a crime, steal your card... or try to eat your hair.

    My professor brother and I have an argument about head and heart, about whether he overvalues IQ while I lean more toward EQ. We commonly have this debate about people—can you be friends with a really smart jerk（怪物）?—but that also applies to animals as well .I'd love it if our dog could fetch the morning paper and then read it to me over coffee, but I actually care much more about her loyal and innocent heart. There's already enough thinking going on in our house, and we probably spend too much time in our heads. Where we need some role modeling is in instinct, and that's where a dog is a vivid example.

    I did not grow up with dogs, which meant that my older daughter's respectful but firm determination to get one required some adjustment on my part. I often felt she was training me: from ages of 6 to 9, she gently schooled me in various breeds and their personalities, whispered to the dogs we met with so they would charm and persuade me, demonstrated by her self-discipline that she was ready for the responsibility. And thus came our dog Twist, whom I sometimes mistake for a third daughter.

    At first I thought the challenge would be to train her to sit, to follow, to walk calmly beside us and not go wildly chasing the neighborhood rabbits. But I soon discovered how much more we had to learn from her than she from us.

    If it is true, for example, that the secret to a child's success is less rare genius than raw persistence, Twist's ability to stay on task is a model for us all, especially if the task is trying to capture the sunbeam that touches softly around the living room as the wind blows through the branches outside. She never succeeds, and she never gives up. This includes when she runs straight into walls.

    Then there is her unfailing patience, which breaks down only when she senses that dinnertime was 15 minutes ago and we have somehow failed to notice. Even then she is more eager than annoyed, and her refusal to complain shows a self control of which I'm not always capable when hungry.

    But the lesson I value most is the one in forgiveness, and Twist first offered this when she was still very young. When she was about 7 months old, we took her to the vet to be spayed（切除卵巢）. We turned her over to a stranger, who was to perform a procedure that was probably not pleasant. But when the vet returned her to us, weak and tender, there was no accusation, no how could you do that to me? It was as though she already knew that we would not intentionally cause her pain, and while she did not understand, she forgave and curled up with her head on my daughter's lap.

    I suppose we could have concluded that she was just blindly loyal and obedient. But eventually we knew better. She is entirely capable of disobedience, as she has proved many times. She will ignore us when there are more interesting things to look at, scold us when we are careless, bark into the twilight when she has urgent messages to send. But her patience with our failings and carelessness and her willingness to give us a second chance are a daily lesson in gratitude.

    My friends who grow up with dogs tell me how when they were teenagers and trusted no one in the world, they could tell their dog all their secrets. It was the one friend who would not gossip or betray, could provide in the middle of the night the soft, unselfish comfort and peace that adolescence plots to disturb. An age that is all about growth and risk needs some anchors and weights, a stable model when all else is changing. Sometimes I think Twist's devotion keeps my girls on a benevolent leash, one that hangs quietly at their side as they walk fast along but occasionally pulls them back to safety and solid ground.

We've weighed so many decisions so carefully in raising our daughters—what school to send them to and what church to attend, when to give them cell phones and with what precautions. But when it comes to what really shapes their character and binds our family, I never would have thought we would owe so much to its smallest member.

    Nola (August 21, 1974 -November 22, 2015) was a northern white rhino 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 20 years 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 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.

    If you could sail around the world with only one companion, who would you choose? Guirec Soudee, a 24-year-old man from France, chose his pet chicken.

    Soudee has been sailing around the world for two years. No matter which country he sails to, Monique, the hen, is by his side. He found her in the Canary Islands and knew right away they were meant to be best companions. "I didn't speak any Spanish and she didn't speak any French, however, we could always have a small talk, even though she didn't understand me." Soudee joked.

    He had always wanted a companion for his journey and originally thought about bringing a cat, before deciding it would be too much work to look after on a boat. Upon meeting Monique, Soudee realized a hen was the perfect choice. He believed they could communicate with each other well.

    Not only does it cost little to raise Monique, but she lays eggs as well — some things that are always a plus in a situation where storing a lot of food can be a challenge. She lays about six eggs a week on average, even in cold climates like Greenland, where Soudee and Monique are docked(进港) now.

    And what happens when the weather at sea gets bad? Usually Soudee lets Monique stay freely on the boat, but when the winds get terrible he ensures she is safe in her hutch so that she doesn't fall out of his boat and into the sea. Another thing Soudee must care for is the rule in every country he visits. They had met with customs officials in Canada. He was permitted to keep her, but he knows they might not always be so lucky.

    Although Monique can sometimes get on his nerves, Soudee says she's much better than a human companion aboard. "She follows me everywhere. All I need to do is shout 'Monique!' and she will come to me, sit on me, listen to my small talk and give me company," he said.

    After visiting Greenland, they'll head down the Bering Strait to Nome, Alaska. From there the destination is undecided, but Soudee will certainly discuss where they should travel to next with Monique.