Shark attacks can be deadly,     1     they are not common. Each year, sharks usually kill fewer than 10 people worldwide, and about 100 people are injured. People are more likely to be attacked in parts of the sea     2     tourists throw in food to bring in sharks. However, people are dangerous to sharks, too. 60 million sharks     3     (kill) for food and medicine every year. As a result, some kinds of sharks may die out completely.     4     (protect) these wonderful animals, some countries have made programs to help them survive.

2 . The Amazing Penguin Rescue

In the summer of 2016, the ship MV Treasure sunk, creating an oil spill. Thirteen hundred tons of fuel oil were flowing right in the middle of the African Penguins’ habitat. Soon the oil covered about 20,000 penguins. Without swift help, the seabirds would have no chance of survival. Volunteers were showing up by the thousands and I also took part in what was the largest animal rescue operation ever.

A warehouse was turned into a rescue center near the habitat and hundreds of pools were built to hold about 100 oiled birds each. When walking into the center, I couldn’t believe my ears. I had expected to walk into a chorus of honking and squawking(尖声叫). Instead, the center sounded like a library. The penguins were dead silent. My heart ached for the painful birds. Cleaning them all seemed like an impossible task. But we had to carry on like doctors in an emergency room. There was no time for doubt. Cleaning oil off a penguin wasn’t easy. Even with more than 12,500 volunteers, it took a month to bathe all 20,000 birds at the center.

While volunteers were busy bathing the oiled penguins, another crisis(危机) was developing. Oil from the spill had started moving north. Tens of thousands of penguins were in the oil’s path. But we already had our hands full with 20,000 recovering birds. If any more birds were oiled, we wouldn’t have enough resources to save them.

One researcher came up with an idea: What if the penguins were temporarily moved out of harm’s way? Experts decided to have a try. Volunteers rounded up the penguins and released them 500 miles away. The hope was that by the time the seabirds swam home, the oil would be gone. The plan worked! Another 20,000 penguins were saved.

The entire penguin rescue took about three months. More than 90% of the oiled penguins were successfully returned to the wild. Looking back on the rescue, I am still amazed by the work of the volunteers. What I could hardly believe was that we accomplished an impossible task.

4 . We are what we eat, and what we eat reveals something about what we are in return. So it shouldn’t be all that surprising that humans are now apparently eating plastic.

A small trial at the Medical University of Vienna found tiny pieces of it in the digestive systems of people from eight different countries. The study involved just eight people and doesn’t tell us what if any effect eating plastic was having on their bodies. We already knew fish were eating plastic. Did we really think it wouldn’t reach back up to the top of the food chain, that the consequences of our own actions couldn’t return to us?

This goes beyond cleaning up the oceans. Six of the eight subjects of the study ate sea not all of them did. Other possible theories involve drinking out of plastic bottle. eating food that’s been wrapped in plastic, or tiny plastic pieces floating in the air which then land on our food. But our environment is so filled now with plastic that it seems that we were going to absorb it somehow.

Does it actually matter? This study can’t answer that question, because all it tells us is that microplastics were found in human wastes. If it’s just passing through the body, then perhaps there’s no damage done. However, if there were evidence of plastics being absorbed and gathering in our internal organs, as some animal studies have suggested, that would potentially be a red flag.

Solving plastic pollution is nowhere near as simple as some campaigners make it sound. Switching away from plastic packaging to other materials would create other environmental dilemmas. Bottling liquids in glass rather than plastic makes them heavier which potentially means more trips to transport them, paper production has a bigger carbon footprint. Even if it were possible to stop using the stuff tomorrow, it would take up to 1,000 years for some of what’s being produced right now to break down.

But just because it’s difficult, it doesn’t mean we shrug our shoulders and do nothing. There is something genuinely mad about a society that is on the one hand crazy about the quality of the food we put in our mouths, and yet also mindlessly eats its own garbage. The war on plastic, it seems, just got personal.

6 . Plastic—Eating Worm

Humans produce more than 300 million tons of plastic every year. Almost half of that ends up in landfills(垃圾填埋场) , and up to 12 million tons pollute the oceans. So far there is no effective way to get rid of it, but a new study suggests an answer may lie in the stomachs of some hungry worms(幼虫).   

Researchers in Spain and England found that the worms of the greater wax moth(大蜡螟) can break down polyethylene(聚乙烯), which accounts for 40% of plastics.

That is to say, part of plastics can be consumed by this kind of worms. The team left 100 wax worms on a plastic shopping bag for 12 hours, and the worms consumed and broke down about 92 milligrams, or almost 3% of it. To confirm that the worms' chewing alone was not responsible for the polyethylene breakdown, the researchers made some worms into paste(糊状物)and applied it to plastic films. 14 hours later the films had lost 13% of their mass—apparently broken down by enzymes(酶)from the worms' stomachs. Their findings were published in Current Biology.

Federica Bertocchini, co—author of the study, says the worms' ability to break down their everyday food—beeswax—also allows them to break down plastic." Wax is a complex mixture, but the basic bond in polyethylene, the carbon—carbon bond, is there as well," she explains. "The wax worm developed a method or system to break this bond."

Jennifer Debruyn, a microbiologist at the University of Tennessee, who was not involved in the study, says it is not surprising that such worms can break down polyethylene. But compared with previous studies, she finds the speed of breaking down in this one exciting. The next step, DeBruyn says, will be to identify where the enzyme comes from. Is it an enzyme produced by the worm itself or by its gut microbes(肠道微生物)?

Bertocchini agrees and hopes her team's findings might one day help make use of the enzyme to break down plastics in landfills. But she expects using the chemical in some kind of industrial process—not simply "millions of worms thrown on top of the plastic."

9 . You might not expect it, but cows are a large source of the greenhouse gases that are driving climate change. Cows produce lots of methane by breaking down the grass, Now scientists have shown that the pollution from cows can be reduced by adding a little seaweed to their food.

Scientists first discovered that seaweed could help control methane from cows several years ago. But this work was done in a laboratory, there were many questions about whether the idea could work in real life.

In the lab studies, the cows were given quite a bit of seaweed, and they would cause losing weight. That wasn't helpful, since cows are often sold by weight. It also wasn't clear if the seaweed would stop working if it was used for a longer period of time.

Now, scientists from the University of California, Davis have answered several of these questions.

The researchers studied 21 cows on a farm for about five months. They taught the cows to get their food from inside a special hood, which allowed the scientists to measure the methane that the cows were giving off. This time, they used a much smaller amount of seaweed, which they mixed with the cows' food.

The results were surprisingly good. In some cases, the cows produced 82% less methane. The improvement depended on the kind of food the cows were given, but even the worst-polluting cows produced 33% less methane.

Over the five months, the scientists didn't see any signs that the cows' stomachs were getting used to the seaweed and starting to produce more methane again.

Another surprise came when they looked at the weight of the cows. The cows that were fed seaweed gained just as much weight as the other cows, but they didn't need as much food.

But there are still some big problems with the idea of feeding cows seaweed. For one thing, there's not adequate seaweed to feed all of the cows in the world. So farmers would have to figure out a way to grow lots of seaweed.

A bigger problem is that for most of their lives, cows live in fields, where they eat the grass. That means there's no chance to feed them seaweed every day. These problems need to be taken seriously if the world is going to avoid the worst effects of the climate crisis.

Still, it's true that something as simple as feeding cows seaweed can help reduce some of the pollution causing the climate crisis.

10 . The Chapramari Forest lies in the eastern area of India.     1     . But a large group of elephants found green grasses along the railway line that crosses through the forest. As the elephants got near and on the tracks at dusk, a passenger train traveling at 50 mph knocked into the herd. Seven elephants were killed, and 10 injured.

    2     . The deaths occur at hot spots in a few Indian states where trains intersect (交叉) with elephant habitats. It's puzzling why this highly intelligent animal would wait on the tracks     3     .

After a collision this past April in Odisha state that killed four elephants, Indian Railways lowered speed limits to as low as 18 mph in several areas in the country's east.     4     . Beginning late last year, railway officials in the east have fixed a kind of equipment that could loudly broadcast the buzz of honeybees, a sound that they hope keeps elephants away given their fear of honeybees. In the northern state of Uttara hand, the forest department is using drones (遥控飞机) to keep track of animal movement.     5     .

More permanent solutions include constructing overpasses or underpasses as safe crossing points for the elephants, elevating the railway track, or getting the track away from sensitive areas.