【推荐1】We often ask these questions: Are African wild dogs really dogs? What’s the difference between African wild dogs and the dogs we know as pets? For one thing, African wild dogs, which live in Africa, only have four toes, while domestic(驯养的）dogs and wolves have five. But you won’t want to count for yourself, because they are truly wild animals.

“Wild dogs are not somebody’s domestic dogs that ran away and didn’t come back, although some people used to think that,” explains Dr. MeNutt, who studies these animals at Wild Dog Research Camp in the African country of Botswana. “They are actually Africa’s wolves, and just like wolves, and they do not make good pets. They need to be out in the wild doing what they are supposed to do — find the food they need to survive and feed their babies.” In fact, they travel so far that researchers have to use radio collars (颈圈) to keep track of them. The collars send out radio signals that tell people where the dogs are. No two wild dogs have the same pattern of coats, so it is easy to tell them apart.

African wild dogs are smart and sociable, like pet dogs. Adult wild dogs, male and female, are willing to take good care of young ones.

Millions of domestic dogs live on the planet, but there are probably fewer than 6000 African wild dogs left. Humans hunt them and farmers who don，t want them to go after cows and sheep poison them. Humans are also destroying the wild, natural habitat (栖息地) they need to survive in. Fortunately, today more farmers are finding other ways to protect their cows and sheep from African wild dogs instead of killing the animals.

After years of heated debate, gray wolves were reintroduced to Yellowstone National Park.     1    By last year, the Yellowstone wolf population had grown to more than 170 wolves.

Gray wolves once were seen here and there in the Yellowstone area and much of the continental United States, but they were gradually displaced by human development.     2    . They went farther north into the deep forests of Canada, where there were fewer humans around.

The disappearance of the wolves had many unexpected results. Deer and elk populations — major food sources (来源) for the wolf – grew rapidly. These animals consumed large amounts of vegetation , which reduced plant diversity in the park. In the absence of wolves, coyote populations also grew quickly. The coyotes killed a large percentage of the park’ s red foxes, and completely drove away the park’ s beavers.     3    .They hoped that wolves would be able to control the elk and coyote problems. Many farmers opposed the plan because they feared that wolves would kill their farm animals or pets.

The government spent nearly 30 years coming up with a plan to reintroduce the wolvers. The U.S. Fish and Wildlife Service carefully monitors and manages the wolf packs in Yellowstone. Today, the debate continues over how well the gray wolf is fitting in at Yellowstone.     4    . The Yellowstone wolf project has been a valuable experiment to help biologists decide whether to reintroduce wolves to other parts of the country as well.

【推荐3】Sharks are now at the edge of extinction. Numbers of oceanic sharks have declined by an alarming 71 percent over the past 50 years, according to research published in Nature on Jan 27. “Such steep declines are shocking even to experts, especially when compared to land animal statistics,” Sonja Fordham at Shark Advocates International, a US-based nonprofit, told New Scientist magazine. This alarming data may be an underestimate of reality due to unreported fish catches, Nathan Pacoureau, the study researcher, noted.

The study analyzed 31 species; 24 now risk extinction, and three shark species are now classified as critically endangered, including the oceanic white-tip shark (远洋白鳍鲨) and great hammerhead (锤头鲨). The study found the decline hit the largest species first before impacting smaller ones over time, according to the International Union for Conservation of Nature (IUCN). It also revealed that shark finning and fishing worldwide have driven the decline. “The Indian Ocean is the worst. There is almost no (fisheries) management at all,” said Pacoureau.

“Overfishing of sharks and rays endangers the health of entire ocean ecosystems as well as food security for some countries,” said Nicholas Dulvy, a professor of Simon Fraser University in British Columbia, Canada. The researchers are calling on immediate action to secure a brighter future for these “extraordinary, irreplaceable animals”, according to the BBC.

Although the situation looks gloomy, the future of sharks is not doomed (劫数难逃的) yet. Twenty-five species have recovered, due to long-term conservation campaigns in the past decades. A couple of shark species, including the great white, have started to recover through science-based fishing limits, Fordham said. These examples “provide living proof that the world can set, and meet, ambitious biodiversity targets”, Jane Smart, global director of the International Union for Conservation of Nature, said in a statement.

【推荐3】One of India’s top engineering schools has restricted Internet access in its boarding houses, saying addiction to surfing, gaming and blogging was affecting students’ performance, making them lonely and even suicidal.

Authorities at the best Indian Institute of Technology (IIT) in Mumbai said students had stopped socializing and many were late for morning classes or slept through them. “Now, a student doesn’t even know who lives two doors away from him because he is so busy on the Internet,” said Prakash Gopalan, dean of Student Affairs. “The old dormitory culture of companionship and socializing among students is gone. This is not healthy in our opinion.”

IIT-Mumbai, with about 5,000 students, is one of the seven IITs across India which are considered to be among the finest engineering schools in the world. They are also a talent pool for global technology giants. But their hard courses, tough competition and lonely campus lifestyle have taken an effect on students. Depressive and dysfunctional lifestyles are known to be common among IIT students, and at least nine have committed suicide in the past five years. Students have unlimited free Internet access in their boarding houses to help them in their studies, but many also use it to surf, chat, download movies and music, blog and for gaming.

“Starting Monday, Internet access will be banned between 11 p.m. and 12:30 p.m. at IIT-Mumbai’s 13 boarding buildings to encourage students to sleep early and to try and force them out of their shells.” Gopalan said. But the move has not gone down well with students who say they hate their lives being regulated. “Now they will say we need to listen to a lullaby (摇篮曲) to go to sleep.” said Rajiv, an electronics student.