2 . The Silk Road is the name of different roads that long ago connected Europe, Africa and Asia. People reached these different places along these roads. Scientists believe people began to travel the Silk Road about 3000 years ago. By the time the Chinese silk trade became important in the world, the Silk Road covered almost 6500 kilometers. It spread from Rome to China, which is from the West to the Far East.

Traders travelling along the Silk Road carried silk, of course. They also carried and traded spices (香料), cloth, valuable stones and gold.

There is a famous old story along the old road. It is said that Roman soldiers travelled through central Asia. They started to live somewhere near the ancient Chinese village of Liqian. Sortie of these Romans married local Chinese women and the story of blue-eyed villages of China was started.

During its busiest period, the Silk Road allowed people from many different cultures and countries to meet each other and mix. The Silk Road allowed the sharing of valuable goods and new ideas. These included people and trading goods from the Mediterranean, Persian, Magyar, Armenian, Bactrian, Indian and Chinese areas. All these peoples travelled the Silk Road, and they shared goods, stories, languages, and cultures.

In modern times, the old Silk Road routes (路线) are still used, but now they are crossed by trains instead of camels and horses. There is even a Silk Route Museum in Jiuquan in China. It has over 35,000, objects from all along the Silk Road. In this way, China protects the history of many countries and peoples.

3 . In habitats across the planet, animals periodically drop everything to walk, fly or swim to a new place. Some animals such as whales and geese learn migration paths by following their parents. Others, including small songbirds, gain the distance and direction of their migration within their genetic code. And some animals use a combination of genetics and culture to guide their migration.

Another group of migrators does not quite fit either model, and researchers have only recently started to figure out how they find their way. The Cory’s shearwater is an oceangoing seabird that migrates over the Atlantic every year. The young do not migrate with their parents, so culture cannot explain their journeys. And the exact paths vary wildly from individual to individual, making genetics equally unlikely.

Cory’s shearwaters are long-lived, rarely producing young successfully before age nine. This leaves an opening for learning and practice to develop their migration patterns. Researchers call this the “exploration-refinement”, and until now it has been hypothetical (假设的) because of difficulties in tracking migratory animals’ movements.

But a team of researchers has done that by attaching small geolocators to more than 150 of the birds aged four to nine. They found that younger birds traveled longer distances, for longer periods, and had more diverse paths than older birds. “We finally have evidence of the ‘exploration-refinement’ for migratory birds,” says Letizia Campioni, who led the study. Younger Cory’s shearwaters are able to fly just as fast as the adults——but they do not, suggesting that the young do more exploring, which gradually fades as they mature and settle into a preferred course.

“Although it may seem less efficient than other strategies, exploration refinement could be beneficial to birds and other organisms in a rapidly changing world due to unpredictable man-made changes,” says Barbara Frei. “It might be safer to repeat a behavior that was recently successful than to rely on patterns that were perfected long ago but might no longer be safe.”

4 . A five-­year-­old dog named Kelsey has been praised as a hero for helping to save the life of her owner who slipped in the snow and broke his neck.

The man, Bob, was alone when he left his farmhouse on New Year’s Eve to collect firewood.Expecting a journey of only several meters, Bob was wearing just long johns (衬裤), a shirt and slippers when he went outside, although the temperature was around －4℃.

After the accident, he was unable to move in the snow. Fortunately, Kelsey came to his assistance.

“I was shouting for help, but my nearest neighbor is about 400 meters away, and it was 10:30 p. m.,” Bob explained. “By the next morning, my voice was gone and I couldn’t yell for help, but Kelsey didn’t stop barking.”

Kelsey’s companion kept him warm by lying on top of him. She licked his face and hands to keep him awake. “Kelsey kept barking but never left my side,” Bob recalled. “I knew I couldn’t give up and that it was my choice to stay alive.”

Bob spent 20 hours in the freezing cold. When he finally lost consciousness, his dog kept barking. Finally, hearing the barking, Bob’s neighbor discovered him at 6:30 p. m. on New Year’s Day and called the emergency services at once. When Bob arrived in hospital, his body temperature was below 21℃. However, doctors were surprised to find that he didn’t have any frostbite (冻疮). They believed it was because of Kelsey’s determination to keep him warm. Dr. Chaim Colen, the doctor who treated Bob, said, “His dog really saved him.He was very fortunate.”

Bob said he was very grateful to both Dr. Colen and his Kelsey. “They saved my life. They are truly heroes!”

5 . An earthquake can strike without warning. But many injuries and deaths from this kind of natural disaster can be prevented if people follow these safety tips.

If you’re inside a building, stay there! One of the most dangerous things to do in an earthquake is to try to leave a building.     1     Drop down onto the ground. Get under an object that is not easily damaged. Hold on to it until the shaking stops. You can also get to a corner formed by two walls with your arms over your head. If you’re in bed when the quake hits, stay there and protect your head with a pillow.

    2     Don’t take shelter under trees, streetlights, telegraph poles or tall buildings. If you are driving stop as quickly as possible and stay away from overpasses, buildings, bridges or anything else that might fall or collapse over you.     3    

If you are trapped in the ruins, cover your mouth with a handkerchief or a piece of clothing. Use your cellphone to call for help if possible. Don’t shout.     4     Tap on a pipe or the wall so rescuers can find you.

Be prepared for aftershocks    5     However, sometimes they even happen months later. Therefore, if you are not in a safe position after the first shock, you should move quickly but carefully to a safer place.

6 . Plastic straws (吸管) have been a major problem in global discussions of environmental damage. Maybe because of their small size, the production cost of straws is low. In many countries, straws are offered freely after buying soft drinks. Therefore, plastic straws are one of the most used plastics and pollutants in the world.

The plastic straw is light and small. Due to their small size, plastic straws are often eaten by sea animals. Environmentalists have shown that the death of many sea animals is caused by eating plastic straws. The other damaging characteristic of plastic straws is that they are made of materials which cannot degrade. That means the materials cannot be changed into small harmless (无害的) ones.

The most effective way of dealing with the environmental pollution caused by plastic straws is the reuse or banning (禁止) the use of plastic straws. Being plastics, the straws can be made new items. Many organizations around the world change used straws into new products. In Africa, local communities collect used plastic straws and use them to make mats and bags. Another way of dealing with environmental pollution caused by plastic straws is placing a ban on their production and use. Experts advise governments to ban using plastic straws to save the environment. A few countries in the world such as Rwanda, Macedonia, China, Kenya have already banned the use of plastic bags and are expected to include plastic straws and bottles. But it will be a long way to do this effectively.

There are few environmentally friendly and biodegradable productions to take the place of plastic straws. These productions include paper straws, bamboo straws. However, such straws are usually expensive as their production cost is high. It’s still a question whether they can entirely take the place of plastic straws.

Is there intelligent (有智力的) life on other planets? For years, scientists said “no.” or “we don’t know.” But today this is changing. Seth Shostak and Alexandra Barnett are astronomers (天文学家). They believe intelligent life exists (存在) somewhere in the universe. They also think we will soon contact these beings(人；生物).

Why do Shostak and Barnett think intelligent life exists on other planets? The first reason is time. Scientists believe the universe is about 12 billion years old. “This is long enough for other planets to have intelligent life,” say Shostak and Barnett. The second reason is size—the universe is huge. “Tools like the Hubble Telescope (哈勃望远镜) have shown that there are at least 100 billion galaxies,” says Shostak. “And our galaxy, the Milky Way, has at least 100 billion stars. Some planets going around these stars might be similar to Earth.”

In the past, it was hard to look for signs of intelligent life in the universe. But now, powerful telescopes (高倍望远镜) allow scientists to discover smaller planets—the size of Mars or Earth—in other solar systems. These planets might have intelligent life.

Have beings from space already visited Earth? “Probably not,” says Shostak. “It’s a long way away. However, intelligent beings may contact us in other way, such as radio signals (信号). In fact, they may be trying to communicate with us now, but we don’t have the right tools to receive their messages. However, this is changing. By 2025, we could make contact with other life forms in our universe and we might help each other.”

10 . A new study has found that all dogs have different personalities—even dogs of the same breed(品种).

Elinor Karlsson studies genetics at the University of Massachusetts. She co-wrote a report about the study, which appeared recently in the publication Science.

Karlsson said, “Every dog really is an individual,” noting that there is “a huge amount of difference” even between dogs that look the same.

At a New York dog park, dog owners talked about the different characteristics of their pets. Elizabeth Kelly owns an English springer spaniel. She called her dog friendly, but also “kind of the queen bee.” In other words, her dog likes to act like it is in charge of other dogs. Suly described her yellow Labrador as “calm, lazy and shy.”

The idea of dog breeds is quite recent. Around 160 years ago, humans began to breed dogs to have certain physical qualities, such as fur, color and ear shape.

Karlsson said her aim was to learn how much a dog’s breed affects their behavior. The answer? Breed does not decide an individual dog’s personality.

Karlsson’s team gathered information from 18,000 dog owners and studied the genetic code of over 2,000 dogs. The researchers found that some qualities are based on genetics. However, it is not sure that two dogs of the same breed will behave in the same way.

For example, huskies and beagles, may be more likely to howl—or make a long, loud barking sound. But many of these dogs do not howl, as owner observations showed.