【推荐1】The Sahara Desert, which covers over 3.6 million square miles of Northern Africa, is one of the most unsuitable places for most animals to live in on the planet today. However, new research conducted by a team of international biologists has found that millions of years ago, the area was filled with frightening animals feeding on meat, including dinosaurs,

“It was the most dangerous place in the history of planet Earth because it was home to so many different kinds of dangerous animals in all shapes and sizes," says study leader Nizar Ibrahim, a biologist at the University of Detroit Mercy.

The researchers found the fossils (化石) of three of the world's largest-known dinosaur species that raised the Kem Kem beds to the status of “the most dangerous place in Earth's history”.

They included the "shark-toothed dinosaurs”. Larger than even the T-Rex, the massive theropods (兽脚亚目恐龙) measured 13 feet tall, 45 feet long, and weighed as much as 17,637 pounds. The creatures sported enormous jaws and teeth up to eight inches long. The mid-sized theropod, which grew to about 26 feet in length, had unusually slim hind limbs (后肢) for its size, suggesting it may have been a swift runner.

The most interesting thing was the Spinosaurus aegyptiacus (埃及棘龙). The massive 50-foot long, 15,434-pound animal had a long nose, similar to those of a crocodile's stomach, and long teeth. The dinosaur's most unusual feature, however, was its tail. Unlike the tails of other dinosaurs, such as the T-Rex, it was flexible with a large surface area.

To test the tail’s abilities, the biologists created a plastic one and attached it to a robotic swimming device. They found that the paddle-like structure was capable of moving sideways, suggesting that the dinosaurs could easily push through water. The researchers believe the dinosaurs were equally comfortable on land, where they came to lay their eggs.

【推荐2】Since 1970, North America has lost more than 2.9 billion birds, according to a study recently published in the journal Science. In less than half a century, the bird population has declined by some 29 percent, or more than 1 in 4 birds. For the first time, researchers have discovered that rare species aren't the only birds suffering population loss. In fact, common birds-including beloved backyard friends like sparrows and blackbirds-are taking the biggest hit.

The new study used nearly 50 years of data collected largely by bird watchers and citizen scientists. "A total of 419 native migratory species experienced a net loss of 2.5 billion individuals," the study says. More than 90 percent of the total loss can be found among just 12 bird families. Some of these widespread birds can thrive almost anywhere. The large-scale loss of these hardy birds reveals they're struggling to survive throughout the world/

Birds are considered indicator species because they're crucial to ecosystems, and their populations anticipate the environment's health. Birds are "amazingly efficient" at spreading seeds. Birds also keep insect populations in check. Even the smallest bird helps control the spread of plants or insects.

The new study, however, identifies the losses without knowing all the causes. Scientists do identify habitat loss as the biggest challenge. Climate change, disrupted migration patterns and pesticide use are also major factors. Industrial agriculture may present a bigger challenge. The species disappearing most rapidly—sparrows, blackbirds and larks—are associated with agriculture. In recent decades, agriculture has grown to produce more food, but cleared landscapes have become unlivable for birds.

“We need to change the way we grow food. Birds are signaling that we are doing it wrong, "as the study says. The study offers the example of the 1990s effort to switch to no-till farming, which reduced greenhouse gases and soil erosion（侵蚀）. “Farmers are innovators. And they've done it before. This is a great opportunity to have a huge impact on birds."

【推荐3】A team of biologists recently studied rain-frogs in the forests of northern Ecuador. While doing so, they discovered a Mindo harlequin toad (五彩蟾蜍). The creature hadn't been seen alive in 30 years. The scientists couldn't believe their eyes.“The three of us spotted it,” Melissa Costales, a conservation biologist, said. Her partners were scientist Cesar Barrio-Amoros and guide Eric Oster-man.“ It took our brains a while longer than normal to recognize that we were watching an Atelopus mindoensis !”Their findings were published in the spring, in the journal Herpetology Notes.

Until recently, 13 of the 25 species of harlequin toads in Ecuador had gone unseen since the 1980s or early 1990s. Climate crisis is damaging their living conditions, and they can't find food that is suitable for them. Besides, people hunt for them to make money. However， scientists hold that most of them had been wiped out by a terrible disease called chytrid, which is especially harmful to the harlequin toad.

The Mindo harlequin is the latest harlequin toad species “to come back from the dead,” says Costales. Since 2003, eight other species have been found, three of them in Ecuador. Costales says the Mindo harlequin may have developed a resistance to the disease. That would explain the toad’s reappearance. And it could spell good news for other harlequins. Since discovering the first one, Cos-tales' s team has found five more. They were all tested for chytrid. None had the disease. But that doesn’t mean the survival of the species is guaranteed, Costales says. The harlequin toad is still endangered.

Costales is developing a conservation plan with a zoology museum in Ecuador. She wants to make sure the Mindo harlequin toad doesn’t fall back into dying out.“Each rediscovery gives us a second chance to develop better conservation strategies (策略) ,”she says.“Not every day do we have the opportunity to rediscover a species that we believed to be extinct.

【推荐1】There has been a very serious decline in the numbers of shallow-water fish as a result of overfishing. People still want to eat fish, so the fishing industry must look at other sources, especially the deep waters of the Atlantic.     1    .

Conservation measures will have to be put in place if these deep-sea fish are to survive. Research on five such species shows that numbers have declined by between 87 percent and 98 percent.     2     Many species could well disappear if the present trend continues. These are species that have been swimming in our oceans for hundreds of millions of years.

The problem is emphasised by the fact that the decline in numbers happened in less than twenty years. Deep-sea fish take a long time to reproduce and normally live for many years.

    3     The average size of such fish also declined, with one species showing a 57 percent decline in average size. This is of particular concern, as large fish tend to produce more offspring than small ones.

None of these facts has been taken into account by the fishing industry. The deep-sea species have been caught as if they were the fast-breeding fish like sardine and herring.     4    

The damage done by overfishing goes beyond the sea environment. Millions of people make a living in the fishing industry.     5     Measures must be taken to not only conserve ecosystems, but also sustain livelihoods and ensure food security.

【推荐2】Hannah Huxford encountered the fry-stealing gull in Bridlington, a coastal town on the Yorkshire coast. Huxford snapped the well-timed photo on her iPhone in 2011; it went viral soon after. A decade later, the fry-stealing gull is appearing on billboards, as part of an advertising campaign for Google.

Researchers recently discovered that food may actually become more attractive to gulls when the birds observe humans handling it first, according to a 2020 study published in the journal Royal Society Open Science.

Because the birds seem to be attracted to food items that they’ve watched humans touch, another of the study’s authors, says that it’s even more important to properly throw food waste and snack wrappers in the trash. “Our findings suggest that gulls are more likely to approach food that they have seen people drop or put down, so they may associate areas where people are eating with an easy meal,” Dr. Laura Kelley said.

The scientists approached 74 herring gulls in coastal towns in Cornwall, tempting them with weighted bags of fried potatoes. Only 19 gulls were curious or hungry enough to linger (逗留), allowing the scientists to place the bag on the ground and retreat a short distance away, waiting in a crouched (蹲下) position to see if a gull would approach.

Their experiments demonstrated that gulls were more cautious about approaching a tempting treat if there was a person nearby who was watching them closely. However, the scientists also found that far fewer of the birds than expected showed interest in investigating the food at all when being stared at.

In fact, people may be able to protect their lunches from gulls by avoiding areas where the birds tend to gather and keeping a closer eye on their meals, she added. “Gulls have a bad reputation but, like all animals, they are just trying to survive,” Goumas said. “We can try to alleviate the conflict we have with them by making changes in our own behavior.”

【推荐3】In Alaska, the US, the grizzly bears are not alone because of Timothy Treadwell. Everyone knows that grizzly bears can be very dangerous to people. However, people can be perilous to grizzly bears, too, because their fur and food are beneficial for some people. In fact, half of the grizzly bears die before they are five years old, even though they can live for about 30 years.

Grizzly bears hibernate every winter. They sleep for several months. During this period, they don’t wake up or eat anything. When they wake up in the spring, the grizzlies are in danger. But Timothy can protect them. He sleeps in a tent near the bears and bathes in a river with them. People do not hurt the bears when Timothy is with them.

Timothy went to Alaska for the first time about 17 years ago. He was attracted by the beauty of the land and the prettiness of the animals. When he learned that people kill many grizzly bears every year, Timothy determined to protect the grizzly bears and to keep the bears safe from danger, so he lives with the bears for four to five months every year. At the beginning, Timothy’s parents didn’t agree, but later, they firmly supported him to do so, because they also wanted to protect bears as him.

Timothy has lived with the grizzlies every spring for about 17 years. Some bears are now his friends. He gave them names. His friend Booble sometimes gives him fish which he likes. His friend Lazy sleeps near his tent every night. Every winter, when the bears hibernate, Timothy returns to his home in California. Then he teaches children and adults about his friends in Alaska.

【推荐1】After decades of work trying to save the giant panda, Chinese officials have announced the species is no longer endangered. The pandas have been reclassified in the country from endangered to vulnerable (易危的) after efforts to increase the population. Now the number has risen to 1,800 in the wild.

“China has established a relatively complete nature reserves system,” Cui Shuhong, director of the Department of Natural Ecological Protection of the Ministry of Ecology and Environment, said on Wednesday. “Large areas of natural ecosystems have been systematically and completely protected, and wildlife habitats have been effectively improved.” The latest classification upgrade reflects their improved living conditions and China’s efforts in keeping their habitats integrated, Cui added.

Bamboo makes up 90% of pandas’ diets, and the animals would likely starve without the shoots (竹笋). Experts believe China’s efforts to replant bamboo forests have been the key to the increase in the population of pandas. Generally speaking, a panda has to eat at least 26 pounds of bamboo every day to maintain its energy, so large areas of bamboo forests are primary to their survival.

Planting bamboo also has advantages for the planet, as the bamboo is grass, not a tree, and is incredibly efficient at absorbing carbon dioxide, as well as emitting (排放) 35% more oxygen than trees.

“The Chinese have done a great job in investing in panda habitats, expanding and setting up new reserves,” Ginette Hemley, senior vice president of conservation at the World Wildlife Fund, told the media. “They are a wonderful example of what can happen when a government is committed to conservation.”

Continuing China’s success will be dependent on the country protecting land from agricultural and urban development. As land becomes rarer, measures will need to be extended to protect more land, to ensure bamboo forests can thrive and as a result, protect the future of the world’s most lovable, lazy, and monochrome (black and white) creature.

【推荐2】The government of Singapore has created a highly developed system that turns wastewater into drinking water. The system involves a network of tunnels and high technology treatment centers.

The system helps reduce ocean pollution, as only a small amount of the treated water is sent into the sea. The United Nations estimates that 80 percent of the world’s wastewater flows back into the oceans without being treated or reused.

Singapore has few natural water sources. The island nation has long had to depend mostly on supplies from neighboring Malaysia.

Low Pei Chin, an expert, told reporters, “Singapore lacks natural resources, and it is limited in space, which is why we are always looking for ways to explore water sources and stretch our water supply. One major plan is to collect every drop and reuse endlessly.”

Parts of the water treatment center are underground. Wastewater enters the center through a 48- kilometer tunnel that is linked to sewers. The center contains a large system of steel pipes, tubes, tanks, cleaning systems and other machinery. It can treat up to 900 million liters of wastewater a day.

In one building, a network of air flow systems has been put in place to keep the air smelling as fresh as possible. Waste that arrives at the plant goes through a cleaning process before powerful pumps send it flowing to areas above ground for more treatment. There, the treated water receives additional cleaning. Bacteria and viruses are removed through highly developed cleaning processes and then disinfected with ultraviolet radiation (紫外线).

Singapore is also in the process of expanding its recycling system. The country will add another underground tunnel and a major water treatment center to serve the western half of the island. Officials expect work on the center to be completed by 2025. By the time the expansion is finished, Singapore will have spent about $7.4 billion on its water treatment systems.

【推荐3】LONDON (Reuters)——Organic fruit, delivered right to the doorstep. That is what Gabriel Gold prefers, and he is willing to pay for it. If this is not possible, the 26-year-old computer technician will spend the extra money at the supermarket to buy organic food.

“Organic produce is always better,” Gold said, “The food is free of pesticides (农药), and you are generally supporting family farms instead of large farms. And more often than not, it is locally   grown and seasonal, so it is more tasty. ” Gold is one of a growing number of shoppers buying into the organic trend, and supermarkets across Britain are counting on more like him as they grow their organic food business. But how many shoppers really know what they are getting, and why are they willing to pay a higher price for organic produce? Market research shows that Gold and others who buy organic food can generally give clear reasons for their preferences—but their knowledge of organic food is far from complete. For example, small amounts of pesticides can be used on organic products. And about three quarters of organic food in Britain is not local but imported to meet growing demand. “The demand for organic food is increasing by about one third every year, so it is a very fast-growing market." said Sue Flock, a specialist in this line of business.