When a leafy plant is under attack ，it doesn't sit quietly. Back in 1983, two scientists, Jack Schultz and Ian Baldwin,reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be an alarm.What the plants pump through the air is a mixture of chemicals known as volatile organic compounds,VOCs for short.

Scientists have found that all kinds of plants give out VOCs when being attacked .It's a plant's way of crying out.But is anyone listening?Apparently.Because we can watch the neighbours react.

    Some plants pump out smelly chemicals to keep insects away.But others do double duty .They pump out perfumes designed to attract different insects who are natural enemies to the attackers. Once they arrive, the tables are turned. The attacker who was lunching now becomes lunch.

    In study after study,it appears that these chemical conversations help the neighbors .The damage is usually more serious on the first plant,but the neighbors ,relatively speaking ,stay safer because they heard the alarm and knew what to do.

Does this mean that plants talk to each other? Scientists don't know. Maybe the first plant just made a cry of pain or was sending a message to its own branches, and so, in effect, was talking to itself. Perhaps the neighbors just happened to “overhear” the cry. So information was exchanged, but it wasn't a true, intentional back and forth.

    Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate(亲密的) than the world we can see and hear. Our senses are weak. There's a whole lot going on.

    A man walked into a small Irish pub and ordered three beers. Bartender was surprised, but he served that man three beers. One hour later the man ordered three beers again. The very next day that man ordered three beers again and drank quietly at a table. This repeated several times and shortly after the people of the town were whispering about the man, who was ordering three beers at once.

    A couple of weeks later, the bartender decided to clear this out and inquired: “I do not want to pry, but could you explain, why do you order three beers all the time?” The man replied: “It seems strange, isn't it? You see, my two brothers live abroad at the moment, one – in France and another – in Italy. We have made an agreement, that every time we go to pub each of us will order extra two beers and it will help keeping up the family bond”.

    Soon all the town have heard about the man's answer and liked it a lot. The man became a local celebrity. Residents of the town were telling this story to newcomers or tourists and even invited them to that pub to look at Three Beer Man.

    However, one day the man came to pub and ordered only two beers, not three as usual. The bartender served him with bad feeling. All that evening the man ordered and drank only two beers. The very next day all the town was talking about this news, some people pray for the soul of one of the brothers, others quietly grieve.

    When the man came to pub the next time and ordered two beers again, the bartender asked him: “I would like to offer condolences to you, due to the death of your dear brother”. The man considered this for a moment and then replied: “Oh, you are probably surprised that I order only two beers now? Well, my two brothers are alive and well. It's just because of my decision. I promised myself to give up drinking.”

    Self-driving vehicles have been proposed as a solution for the rapidly increasing number of fatal traffic accidents, which now cause 1.3 million deaths each year.

    While we have made great progress in advancing self-driving technology, we have yet to explore how autonomous vehicles will be programmed to deal with situations that endanger human life, according to a new study published in Frontiers in Behavioral Neuroscience.

    To understand how self-driving cars might make these judgments, the researchers looked at how humans deal with similar driving dilemmas.

    When faced with driving dilemmas, people show a high willingness to sacrifice themselves for others, make decisions based on the victim's age and turn onto sidewalks to minimize the number of lives lost. Ethical（伦理的）guidelines tend to disagree with human instincts（本能） in this case, saying that no life should be valued above another.

    “The technological advancement and adoption of autonomous vehicles are moving quickly but the social and ethical discussions about their behavior are lagging behind,” says lead author Lasse T. Bergmann from University of Osnabrück, Germany.

    Automated vehicles will eventually outperform their human counterparts, but there will still be circumstances where the cars must make an ethical decision to save or possibly risk losing a human life.

    The study is especially relevant considering earlier this year a self-driving Uber car struck and killed a passenger in Arizona, in an incident widely regarded as the first death resulting from an autonomous vehicle.

    An ethics commission launched by the German Ministry for Transportation has created a set of guidelines, representing its members' best judgement on a variety of issues concerning self-driving cars. These expert judgments may, however, not reflect human instinct.

    Bergmann and colleagues developed a virtual reality experiment to examine human instinct in a variety of possible driving situations. It was based on the well-known ethical thought experiment—the trolley problem.

    In this experiment, there is a trolley running down the railway tracks. Ahead, on the tracks, there are five people tied up, unable to move, and the trolley is headed straight for them. A person is standing some distance off in the train yard, next to a lever（操作杆）.If he pulls this lever, the trolley will turn to a different set of tracks. However, there is one person tied up on the side track. Does the person choose to pull the lever and kill one person, or do nothing and let five people die?

    Bergmann recognized that the majority of people would not approve of the proposal made by the ethics commission that a passenger in the vehicle should not be sacrificed to save more people. “We find people chose to save more lives, even if this involves turning onto the sidewalk, endangering people uninvolved in the traffic incident,” said Bergmann, “Furthermore, subjects considered the factor of age, for example, choosing to save children over the elderly.” He also realized further discussion and research were needed. “Driving requires a complex weighing of risks versus rewards, for example, speed versus the danger of a critical situation,” Bergmann explained.

    Reader: For six years, I've run an office that has two employees: me and my boss. He used to be so appreciative that I didn't mind doing a little extra, but about two months ago, he started being rude and demanding. Now he even yells when I don't have time to bring his favorite wine to his home after work.

    This change started when we met a wealthy new customer, who is a huge jerk (古怪的人) -- my boss's new behavior is just like his.

    My boss is a good man; he and his family have treated me like a little sister. Is there a good way to discuss this with him?

    Karla: Sounds like your new customer has set a bad example to your boss. You need to remind your boss that you're in his corner-- but you're not his slave. My suggestions are as follows.

    Start with a simple question in a calm moment: "Is everything okay?"

    State the truth: "Until recently, I've felt like a valued teammate. But our relationship has become tense. Your expectations of me seem to have changed. Although I used to do occasional personal businesses for you as a favor, now it seems expected."

    Draw your lines: "If you think my job description needs to change or my performance is not good enough, let's discuss that. Otherwise, I need you to stop yelling at me and to respect my personal time."

    Ideally, you'll get an apology and a promise to do better. After that, it's a matter of reinforcement (加强) . If he starts yelling, look at him with a calm expression. After he cools down, restate his request and add, "Is that correct?" For the unreasonablerequest, such as fetching his favorite wine after work: "I'm afraid I can't take care of that for you." If he keeps acting like a jerk, there are bosses out there who will better respect your time and talent.

    Karla L. Miller is ready to hear your work dramas. Send your questions to wpmagazine@washpost.com.

    The associates I hired in my bicycle and lawn mower shop like myself were never perfect; however, they were excellent. Working with them as they improved taught me new ways to show forgiveness, understanding, and patience.

    One day the placement officer asked me to interview a young man who was having trouble finding a job. He told me that David was a little shy, did not talk much and was afraid to go on with interviews. He requested that I give David an interview just for practice. He plainly told David that I had no positions open at the time and the interview was just for practice.

    When David came in for the interview, he hardly said a word. I told him what we did at the bicycle shop and showed him around. I told David to keep showing up because the number one thing an employer wanted in an associate was dependability. David was very quiet (he was evaluated as a slow learner in school).Every ten days or so, for weeks after the interview, David walked into the bicycle shop and stood by the front door. He never said a word, just stood by the door.

    One day, shortly before Christmas, a large truck came to the shop, packed with 250 new bicycles. It had to be unloaded right away or the driver would leave. It was raining. Some of my workers (without physical limitations) chose not to brave the weather to get into work, so I was short-handed. It seemed everything was going wrong and on top of it, David came in the front door and just stood there. I looked at him and shouted,“Well, all right! Fill out a time card and help me unload this truck!”

    David worked for my bicycle shop for eighteen years. He came to work every day thirty minutes early. He could talk; however, he rarely chose to. He drove my truck and made deliveries. The customers would praise David, saying,“He doesn't talk, but he really shows you how to operate a lawn mower!”

    Yellowstone National Park is the flagship of the National Park Service and a favorite to millions of visitors each year. The park is a major destination for all members of the family. By driving the grand loop road, visitors can view the park from the comfort of their vehicle and also take a rest at one of the many roadside picnic areas.

    How much is the entrance fee?

    $25 - Private, noncommercial vehicle;

    $20 - Motorcycle or snowmobile (winter);

    $12 - Visitors 16 and older entering by foot, bike, ski, etc.

    This fee provides the visitor with a 7-day entrance permit for both Yellowstone and Grand Teton National Parks.

    A $50 park annual pass provides entrance for a single private non-commercial vehicle at Yellowstone and Grand Teton National Parks. The $10 Interagency Senior Pass (62 and older) is a lifetime pass available to U.S. citizens or permanent residents.

    Where can you stay?

    Inside Yellowstone, you can choose to stay in modern or historic hotels and cabins inside the park like the Old Faithful Inn, the world's largest log structure. For those who want to be a little closer to nature, there are 12 campgrounds with a range of services from primitive pit toilets to shower and laundry facilities. There's also RV camping with and without dumping stations.

    Staying outside the park gives you unique Old West experiences but still keeps you close to park attractions.

    If you're taking a road trip to Yellowstone, you'll want to check out our Hotels and Cabins On The Road section.