You may have seen a talking parrot on a TV show, in a movie, or even in someone's home. The parrot has learned to copy sounds that people make. Birds are not the only animals that can copy the noises they hear. Dolphins, bats, and some apes also copy sounds. Now we can add elephants to this list of copycats.

    Dr. Joyce Poole is a zoologist. She studies the sounds of elephants. While she was in Kenya, she would hear strange noises made by Mlaika after sunset. Mlaika was a 10-year-old African elephant.

    Mlaika lived near a highway. Dr. Poole says, “I could not tell the difference between Mlaika's call and the distant truck noise.” She and other scientists studied Mlaika's sounds. It turned out that Mlaika was copying the sounds of the trucks driving by. Why would Mlaika copy trucks that she heard going by on the highway? Animals that are able to copy sounds may enjoy practicing new sounds. When they are kept outside of their natural environment, they may copy unusual sounds. That may be why an elephant would copy the sound of a truck.

    “Mlaika was not the only copycat elephant,” Dr. Poole says. Calimero is a 23-year-old male African elephant. He spent 18 years with two female Asian elephants. Asian elephants make chirping sounds (sounds made by birds) to talk with one another. African elephants usually do not make chirping sounds. But Calimero now does. He is copying his Asian elephant friends. Dr. Poole says that elephants need to form bonds with their family and friends. She says, “They make sounds to communicate with each other. When they are separated, they use sounds to keep in contact.”

    Parrots, dolphins, humans, and elephants show that being a copycat is one way that animals and people make new friends and keep old ones.

Top attractions

    Amsterdam is most famous for its artistic heritage. This tradition is proudly on display in the Rijksmuseum (translates as State Museum). Once you've taken in all that has to offer, artists, history fans, and families shouldn't pass up the chance to visit the Van Gogh Museum —containing around 700 paintings and drawings by Vincent and his contemporaries (同时代的人), including Gauguin, Monet, and Toulouse-Lautrec.

    Amsterdam is also home to the Anne Frank Museum, where Anne hid with her family during the Nazi occupation of the Netherlands. On a lighter note, taking a canal cruise through its extensive waterways is a rewarding way to see the Dutch capital.

    Art lovers get their kicks at:

    ♦♦ The Van Gogh Museum Rijksmuseum Museum het Rembrandthuis

    Food and drink

    Cheese lovers love Amsterdam. You can find an excuse to eat cheese at any time of the day here. Gouda is Holland's favorite, developing a more intense flavor the longer it's aged. Find a selection at the markets，try a cheeseboard at dinner time, or just order cubes with mustard for dipping to accompany a drink.

When you're hungry for non-cheese food groups, you'll find Michel in-starred restaurants, vegetarian, and organic restaurants that accompany an array of global cuisine. For old-fashioned and modern Dutch food, try these Amsterdam restaurants: Moeders, Haesje Claes, Loetje, Greetje, and De Silveren Spiegel.

Don't leave without tasting:

    ♦♦ Patat (hot chips with toppings) Stroopwafel (waffle cookie) Chocomel (chocolate milk)

    Amsterdam Fast Facts

    Approximate flight times:

    ♦♦NYC/Newark 7 hours 20 minutes Philadelphia 8 hours Boston 7 hours

    ♦♦Miami 9 hours 45 minutes Los Angeles 10 hours 15 minutes

    Entry requirements: Passport must be valid for at least 3 months beyond your planned departure from the Schengen area and have 2 blank pages for entry stamp.

    Disney World is a very popular attraction. But going there can be costly. Here are some suggestions that can help you save money.

    Instead of eating at the park, get premade food from a nearby grocery store or even make your own lunch. Also, make sure to take your own water with you because spending $3 on water will make your stomach hurt. Another idea is to pack snacks or quick and cheap pick-me-ups as you make your way around the park.

    Of course you're going to want to take some Disney souvenirs home with you, but you'll quickly realize that it comes with a price. Before buying anything, make sure you have a plan. Some suggestions for keeping costs down include picking your own pearl at the Japan store at Epcot, which is all about the experience and only $15.95 plus tax, or even getting special tradable collection pin that you can trade with Disney cast members or other guests.

    When you go to Disney World on rainy days, you may catch a lot of showers. But you don't have to. Go to a local Dollar Tree and buy disposable ponchos（一次性雨披）for $1. The ponchos at Disney are probably more durable（耐用的）, but they cost $9. For a family of five, the Disney ponchos would cost $45 versus spending $5 at the dollar store.

    It costs $17 to park in Disney for a day. Luckily, most non-Disney resorts offer free shuttles（来往的班车）to and from the park and all Disney resorts offer free transportation for guests as well. If you like to be on your own schedule without worrying about when the shuttle comes, then parking is your only choice. But waiting for the shuttle and going by a schedule isn't really difficult, either.

Scholastic Art: What is your job?

Jayson Fann: I build human-sized nests all over the world.

SA: Can people sit in your nests?

JF: Yes! People have dinner parties in my nests. They read and relax in them. Some of my nests even have several rooms. My nests are even used as hotel rooms.

SA: How do you make a nest?

JF: First, I make a design for the nest. Then I review the design with my client（客户）. After the design is final, I collect wood and work with a team to build it.

SA: What do you use to make your nests?

JF：I use eucalyptus（按树）wood， which is soft and easy to bend when it is young and freshly cut. But when it dries, it becomes extremely hard. So it holds its shape and can support weight. But the structure's strength also comes from the engineering -- how I weave the wood, and how I join major sections by bolting（用螺栓固定）them together.

SA: What makes a great nest design?

JF: Placement is important. The lines of the branches（树枝） create movement and energy, resulting in a cleaner, simpler background -- such as smooth stone or the sky -- which really fits the nest. For me, it's all about balance.

SA: What skills do you need for your job?

JF: You have to be able to draw and use different artistic tools. But you also have to know how to speak to people -- your clients and the people who work for you.

SA: What inspires you?

IF: I love to see how other artists, like Andy Goldsworthy, take common and natural materials and make something special with them.

SA: What is the best part of your job?

JF: I get to be creative in a way that doesn't harm the environment!

    Depression(抑郁) can be a destructive illness, plaguing millions of people worldwide with feelings of sadness, hopelessness, and fatigue. Despite numerous antidepressant drugs, as many as a third of patients don't respond to medication. This has forced doctors to be more creative in finding different treatments for the condition.

    In the past two decades, researchers have tied depression to a seemingly unrelated condition: inflammation(炎症), the body's natural response to stress. It could rise from injury or inflection, or even emotional issues like an unhappy marriage or problems at work. Some amount of inflammation is generally beneficial, as it increases production of cytokines(致癌因子)，proteins that help us heal and protect us from the effects of overwork.

    But excessive cytokine levels, and the inflammation they bring on, could come at a cost—a number of studies suggests that high levels of cytokines could contribute to depression.

    Cytokines can reach the brain several ways: directly through the blood-brain barrier or indirectly by binding to nerve fibers elsewhere, which send signals to the brain to produce the inflammation molecules. In the brain, cytokines can disturb the production and release of several important signaling chemicals, including serotonin, dopamine and glutamate, which help control emotion, appetite, sleep, learning and memory. It's though that a lack of serotonin activity in the brain causes depression; most antidepressants increase the activity. But cytokines also have been shown to activate stress hormone signaling in the brain, which man also serve to develop depression.

    With all the evidence implicating inflammation in depression, doctors have been anxious to test anti-inflammatory drugs as a potential treatment. Four small studies published between 2006 and 2017 by research groups in Europe and Iran found that adults diagnosed with depression who took aspirin or another anti-inflammatory drug called Celecoxib, along with an antidepressant, got more relief from feelings of sadness, hopelessness, guilt and fatigue compared with those taking an antidepressant alone. However, Andrew Miller, a professor of psychiatry at Emory University, thought something was wrong in these small, limited studies. None of them looked at whether the participants had to have high levels of cytokines before they'd see a benefit from anti-inflammatory drugs.  "Unfortunately, much of the field has fallen into the trap of viewing inflammation as the be-all, end-all," Miller says. He and his colleagues wanted to see whether the effect of these drugs was limited to the depression patients with high cytokine levels, or if it helped all people diagnosed with depression.

    If you walk through the doors of one of the Smithsonian Institution's museums in Washington, D.C., you may be greeted by an unusual guide. A Japanese tech company recently sent 25 humanoid robots to the Smithsonian. All of them are named Pepper.

    Each Pepper stands 4 feet tall and has a computer screen attached to its body. Built by SoftBank Robotics, the robots are programmed to share information about the museum in which they are based.

    "Pepper is basically an experiment," Goslins, director of the Smithsonian's Arts and Industries Museum, said. "The idea is to explore and see how a robot performs in this kind of environment."

    Museum visitors communicating with Pepper. The robot can tell stories and answer basic questions. People even take pictures and dance with it.

    "The robot draws big crowds," said Allison Peck, director of marketing at the Hirshhorn. "People just love Pepper."

    According to the Smithsonian Institution's website: "Pepper gives our museum workers a new way to reach and serve visitors." For example, Pepper teaches Swahili words to visitors of the "World on the Horizon" exhibit at the Smithsonian's National Museum of African Art.

    Pepper also has the special ability to draw guests to less-visited areas of the Smithsonian's museum. When Pepper is placed in a spot, crowds are attracted to that place.

    When not educating museum visitors, Pepper stays in the Smithsonian offices, getting charged and programmed. After being charged, Pepper can run for about 8 hours at a time.

    Pepper plays an important role, but the robot "is not meant to take away human jobs at the museum," Goslins explained. "It is meant to give our visitors a more enjoyable experience while they are here with us."