1 . Landfills are places where a large amount of waste and other refuse is buried in the ground. They are responsible for releasing a large amount of planet-warming methane gas into the atmosphere, a new study suggests.

The study, which was published in Science Advances on Wednesday, is aimed at helping local governments carry out targeted efforts to limit global warming by identifying areas of major concern. For this purpose, the scientists used satellite data from four major cities around the world — Delhi and Mumbai in India, Lahore in Pakistan and Buenos Aires in Argentina.

Based on the collected data, the scientists have drawn the conclusion that landfills are the third-largest source of methane emissions (排放) worldwide, after oil and gas systems and agriculture. And further investigation shows that the methane released from the landfills is generated from the decomposition (分解) of natural waste in them, like food, wood or paper.

Methane, though only accounting for about 11 percent of greenhouse gas emissions, traps 80 times more heat in the atmosphere than CO₂. Scientists estimate that at least 25 percent of today’s warming is driven by methane from human actions. That’s why landfills are partly to blame for the global warming.

Joannes Maasakkers, a leader of the study, said, “We found that these landfills, which are relatively small compared to city sizes, are responsible for a large part of total emissions from a given area.” Another scientist, Euan Nisbet, who was not part of the study, said, “This new work shows just how important it is to manage landfills better, especially in countries like India where landfills are often on fire, resulting in a wide range of damaging pollutants (污染物).” He also added that the newer satellite technology and on-the-ground research make it easier for researchers to identify “who is polluting the world”.

2 . Bonobos often form friendly relationships with other bonobo s in separate social groups — the first time this has been seen in non-human primates (灵长类). This is in line with humans, but in contrast to chimpanzees, another primate, which frequently kill chimps in other groups. The findings challenge the idea that humans evolved (进化) from violent apes, says Surbeck at Harvard University. “This potential to form cooperative links between different groups is not uniquely human and it might have occurred earlier than we thought,” he says.

Many animals cooperate, but they seem to do so only with those within their social circle, or in-group. Hostile (敌对的 ) interactions between groups are common among animals, including chimpanzees, so scientists have often assumed that hostility towards other social groups in humans is natural, says Samuni, also at Harvard. However, humans also often cooperate with people in different social circles, for example, by trading or teaching.

Bonobos are one of our closest living relatives. They are less studied than chimpanzees, but are known to be more peaceful, says Surbeck. To learn more about interactions between groups, Surbeck and Samuni observed 31 adult bonobo s from two social groups in Congo over a two-year period. The pair documented 95 encounters between the groups, which represented about 20% of their total observation time. Unlike chimpanzees observed in previous studies, they showed cooperation with out-group members. In fact,10% of all mutual grooming (梳毛) and 6% of all food sharing occurred among members of different social groups.

While bonobo s that groomed others usually got an immediate benefit, food sharing rarely resulted in a gift in return. This suggests that their actions were “not just motivated by selfish interests or immediate rewards”, Surbeck and Samuni report.

Otten, a researcher from the Netherlands, finds the study “exciting”, especially as it “challenges the idea of human exceptionalism” with regard to out-group cooperation. Otten says the bonobo s that were most cooperative within their groups were the same ones that cooperated more with out-group members. This agrees with findings from humans. “Scholars used to believe that in-group ‘love’ goes together with out-group ‘hate’, but recent research suggests that often in-group cooperators are also out-group cooperators,” he says.

3 . Have you ever wondered what happens to your mobile phones and laptops after you throw them out to make way for a newer model? According to its latest Global E-Waste Monitor, India is the third top producer of e-waste in the world. E-waste in Indian landfill goes on to pollute soil and groundwater, affecting food supply systems and water sources.

Thankfully, the country has a new group of artists who are changing these thrown mechanical items-from mobile phones to old televisions- into large murals (壁画) and artworks to creatively show their concern for the waste problem.

Over the past quarter of a century, Mumbai’s Haribaabu Naatesan has transformed hundreds of tonnes of e-waste into art, integrating elements from nature and industry. “I get my waste material from friends, relatives and neighbours who know my interest in e-art and send me bags of thrown electronic appliances,” says Naatesan. Over his career, he has created huge murals for several companies. He has also showed his work at the India Art Fair, as well as several other national displays.

Another artist Vishwanath Davangere has also long worked with e-waste. He likes to take apart old laptops and reassemble (重新组装) them into birds, animals and plants. After retirement, he started pursuing this hobby more seriously and started selling his creations across the world. His most outstanding works include a robotic Egyptian statue with glowing red eyes and a Milky Way made from keyboard keys. He hopes to enable others to reconsider their own consumption habits and make more environmentally conscious choices.

“By giving e-waste a second chance, I aim to raise awareness about the environmental impact of electronic waste.” says Davangare, who today has a collection of more than 600 eco-art objects.

4 . Sleep is so important that it has long interested scientists. Scientists have studied everything from mice to fruit flies in the lab to get a better understanding of what happens when animals sleep and why they do it. However, gathering data (数据) on how animals sleep in their natural habitat has always been hard to do.

But scientists did just that with wild chinstrap penguins in Antarctica. In doing so, researchers found the birds took over ten thousand microsleeps throughout the day — adding up to a 11-hour-long sleep.

To study the penguins, scientists put devices (设备) into a small group of penguins’ brain and neck muscles, which provided the brain wave and location data. The devices had never been used before, so this data collection was only supposed to be a test. However, the process went so well and the data was published in this study.

Researchers found that the microsleeps last only seconds. Researchers think that being able to sleep for such a short time might help the animals avoid predators (捕食者) that might more likely attack if the penguins were asleep for longer — especially when one parent goes out feeding in the ocean for days, leaving the other parent to protect the eggs from predatory birds.

The study is an early insight into a relatively large missing scientific knowledge about sleep.

“Almost every study on sleeping birds discovers something new, something we didn’t know about before,” says study co-author Paul-Antoine Libourel.

Vladyslav Vyazovskiy, a sleep neuroscientist at the University of Oxford who didn’t join in the study, is excited about this new data because “most of what we know about the animal sleep was gained in laboratory conditions, which are totally different from conditions where sleep developed”.

5 . San Francisco’s waterfront (海滨) is on the National Register of Historic Places for good reason.

Its beautiful old landmarks, like the Ferry Building and the Bay Bridge, have been seen in many books, TV shows and movies—from the stories and novels of Jack London to the 1970s TV series The Streets of San Francisco. The future of San Francisco’s waterfront, however, isn’t safe.

In 2016, the National Trust for Historic Preservation put part of the city’s shoreline on its list of the U. S.’s most endangered historic places, in part because of the threat of sea level rise. The waterfront landmarks of many cities are under increasing threat from floods and rising sea levels brought on by human-driven climate change. St. Mark’s Basilica in Venice, Italy and the Venice Beach boardwalk in Los Angeles face similar challenges to San Francisco.

“The whole issue of climate change and historic preservation intersects (交织) right at the waterfront,” said Elaine Forbes, director of the Port of San Francisco. As she watched the boats come and go on a sunny afternoon, Forbes said, “Sea level rise hasn’t historically been as much of a threat to San Francisco as major earthquakes.” However, that’s changed. Parts of the main road that runs along the waterfront have flooded from heavy rains in recent years. The state estimates (预估) the water could rise up to about two and a half feet above its present level by 2060, and possibly up to seven feet by the turn of the century.

Now, San Francisco is considering measures to save its historic shoreline. But the growing magnitude and frequency of the climate-related threats, the high costs and effort needed in saving heritage sites, and competing ideas about what’s worth saving and what isn’t, can make it hard for cities to know what to do first.

Jeremy was with his father in South Africa, which was far from his hometown Wales. He rarely spent time with his father, a famous wildlife photographer. So far, he wasn’t sure he liked following his dad around. The work seemed mostly hot and boring.

“Ready?” Dad asked. Jeremy nodded and they climbed into the old truck. As the truck moved noisily across the rough dirt, Dad chatted with the local guide Ben. And Jeremy watched for animals.

Suddenly, there came a big crash from the car. Jeremy was shocked to find that the door had fallen off! “It might be a blessing (幸事) in disguise! Now we can see better,” Dad said. Ben threw the door into the back of the truck.

They stopped near a river. Ben said he was friends with the elephants that sometimes gathered here. Maybe they’d see some. Before long, Jeremy saw a small group of elephants in the distance, moving slowly through the grassland towards the water. Dad leaped out of the truck and focused his camera on the largest elephant, whose two long teeth shone in the sun. Jeremy spotted a very young baby elephant walking between two adults. It was tiny, by elephant standards. The two adult elephants kept stopping to wait for their baby.

Jeremy watched as the group neared the river. They trumpeted loudly and flapped their large ears to cool themselves down. Then several larger elephants jumped in the water up to their ears. However, Jeremy lost sight of the baby. Where was it? Then he saw. It was in water up to its eyes, holding its trunk (象鼻) up above the water. Jeremy hoped it could breathe through its trunk, because its mouth was underwater.

Other elephants were using their trunks to spray (喷洒) themselves with the cool water, splashing and playing in the water. It was an elephant party. But the baby elephant was in trouble. “Look!” screamed Jeremy. The bank was too steep (陡峭的) for the baby. It couldn’t climb out of the water. Other elephants tried pushing it, without success. The mother was anxious.

Suddenly, Jeremy got an idea and rushed to the back of the truck.

The Beijing Central Axis(中轴线) has taken one more step ahead to become     1     UNESCO(联合国教科文组织) World Heritage Site,     2     will be part of China’s 2024 application project.

The Beijing Central Axis, seen as one of the most important     3     (represent) of Chinese civilization, refers to the core area of the ancient capital city that     4     (stretch) 7.8 kilometres from the Yongding Gate in the south         5     the Bell Tower and Drum Tower in the north. This area tells stories of emperors from the Yuan Dynasty (1279-1368) to the Qing Dynasty (1644-1911)     6     records the lives of both popular figures and common people.

    7     (vary) methods to advance the application have been used, including digital technologies. For instance, visitors can travel through time and space     8     (free), moving between the past and the present, and learn about 14 cultural heritage sites along the Central Axis by using a newly-launched mobile application.

When talking about the decision, Li Zhou, vice president of the Chinese Commission for the International Council on Monuments and Sites, told Global Times that members     9     (join) in the application work felt pressed for time, as there were still many preparations waiting     10     (complete).