【推荐1】Despite the bad reputation of sharks, they are crucial to the health of the marine ecosystem and can even help fight climate change.

In the shallows of Shark Bay, Western Australia, seagrass is food for the sea cows, which can weigh as much as 500 kg and eat roughly 40 kg of seagrass a day. Sea cows are a rich source of food for tiger sharks. By keeping the sea cow population controlled, tiger sharks here help the seagrass grow sustainably. A booming seagrass meadow stores twice as much CO₂ per square mile as forests typically do on land.

But tiger shark numbers are declining. Off Australia’s northeast coast of Queensland, tiger sharks are estimated to have fallen by at least 71 percent, largely due to overfishing. A reduction in tiger sharks means more seagrass consumed by herbivores (食草动物) and less carbon stored in sea vegetation. This raised the question: What if they were absent from the Shark Bay — would the seagrass-dominated ecosystem survive?

To find out, researchers led by Rob Nowicki of Florida International University, spent time in Eastern Australia, where shark numbers were lower and sea cows ate seagrass largely undisturbed. “When uncontrolled, sea cows can rapidly destroy wide areas of seagrass,” said Nowicki.

Those findings emphasized that tiger sharks were playing an important role in preventing the reduction of seagrass in Shark Bay. If their populations continue to decline, the resilience of carbon-rich ocean ecosystems will likely decrease.

When it comes to stimulating shark numbers, there have been movements toward more sustainable fishing, but a large percentage of the industry have not changed their methods, which is a reason why the population of many marine top predators (捕食者) continues to decline.

Aside from supporting sustainable fishing, Nowicki said the only way to truly protect marine life is to reduce our global greenhouse gas emissions. “Ultimately, if we are going to protect our ecosystems in the centuries to come, we are going to need to solve climate change while undertaking species protection at the same time.”

【推荐2】I started considering the power of dogs during one of my daily walks around my neighborhood. Almost invariably, I’ll run into at least one person walking his dog. It’s a joyous moment to approach the dog and pet it. I always walk away from these exchanges feeling just a bit more relaxed and happy. And that got me wondering: Could these short interactions with other people’s dogs actually be good for me?

“Absolutely. I think it is safe to say that animals are beneficial to our mental and physical health,” says Nancy Gee, a professor of psychology at Virginia Commonwealth University. Gee says there’s some evidence that the act of actually touching a dog might be an important part of the calming effect. For instance, one study done in Canada found college students reported less stress and reduced feelings of homesickness after brief interactions with dogs, and that the effect was much bigger in those who actually got to pet the animals.

Now, the therapy (治疗) dogs used in research are screened for things like friendliness, good behavior and responsiveness to their handler’s cues (提示). And of course, not everyone is a dog person. “Pets are not a panacea (灵丹妙药),” Gee says. “They’re not necessarily going to be great for every single person. But for people who really connect with the animals, they can make a big difference.”

Research on the health benefits of human interactions with animals, especially with dogs, has exploded in recent years, thanks to the support of the National Institutes of Health and the Waltham PetCare Science Institute. Though the field is still young, Gee says the quality of the evidence is improving all the time, including more randomized controlled trials looking at short interactions. “We’re seeing really nice effects,” she says. “We actually saw those effects one month later. And there’s some evidence that they may exist six months later.”

【推荐3】October 19th marks the beginning of Diwali, the Hindu festival of lights which is marked by colorful but harmful fireworks across India. But this year, the country's top court has moved to carry out a complete ban (禁令) on the sale of fireworks in and around New Delhi. The decision is intended to help improve the Indian capital's poor air quality, but will it work?

It is reported that air pollution led to 1.1 million deaths in India in 2015. New Delhi, considered among India's worst cities in terms of air quality, is on the front line in fighting the harmful effects. But at present, the government's pollution policy largely appears after pollution rather than before pollution. The smog-reducing measures, which include banning trucks from the city's roads and closing coal-fired power plants, are only carried out during periods of extreme pollution.

Air quality measurements provided by the Delhi Pollution Control Committee record smog levels across the city in real time. Those levels are based on the amount of PM 2.5, which are considered particularly harmful because they are small enough to get deep into the lungs and pass into other organs (器官)，causing serious health risks.

The sale of fireworks was illegal last November following the situation of dangerously high PM 2.5 levels immediately after Diwali. However,the Indian Supreme Court thought a complete ban would be an extreme step. As a result,that order was reversed (撤销) this month. It is believed by the public that the government is unlikely to provide a lasting solution.

Fireworks aren't the only reason behind New Delhi's smog. In fact, New Delhi's pollution is also affected by its unfortunate geography. Sitting in a natural bowl and Surrounded by industrial and agricultural centers, the city keeps much of the pollution.

【推荐1】Michelle Yeoh, a famous name in Chinese cinema, made history on Sunday night by becoming the first Asian woman to win the Academy Award for best actress.

The Malaysian-born actress took home the celebrated award for her extraordinary performance in the multiversal comedy Everything Everywhere All at Once.

The film, where Yeoh plays a struggling laundromat(洗衣店) owner who ends up saving the multiverse(多元宇宙), swept the Oscars with a total of seven awards, including for best picture and best director, making it the biggest winner of the night.

“For all the little boys and girls who look like me watching tonight, this is a beacon of hope and possibilities,” the actress said in her acceptance speech in Los Angeles, to emphasize that one must dream big as dreams do come true.

The actress also used her speech to honor her 84-year-old mother, Janet Yeoh. “I have to dedicate this to my mom and all the moms in the world because they are really the superheroes, and without them none of us would be here tonight,” she said.

After taking off in kung fu cinema in Hong Kong, Yeoh first appeared in Hollywood in the 1997 James Bond movie Tomorrow Never Dies. She gained international recognition for her role as a swords-woman in Ang Lee’s famous film, Crouching Tiger, Hidden Dragon, which won three Oscars in 2001.

Yeoh has been heavily in demand since her role as a controlling matriarch(女家长) in Crazy Rich Asians(2018). She has become one of the most influential stars of Chinese descent(血统) globally, said Shen Dan, a senior critic of the Beijing International Film Festival.

“Everything Everywhere All at Once seems to be specifically crafted for Yeoh because the movie reflects her decades-long efforts to raise the cultural significance of Asian-themed films worldwide,” Shen added.