【推荐1】 The unique ocean animals were discovered by a team of scientists led by Dr. Christine Dudgeon from Australia’s University of Queensland during a 12 year global conservation study.

The newly-found sharks have evolved (进化) to survive in low oxygen environments, enabling them to hunt during low tides. The researchers believe their ability to use their fins (鳍) to walk affords the sharks a remarkable edge over the smaller animals they try to hunt. “While they are super hunters in their shallow habitat, the tiny sharks present no threat to people,” says Dudgeon. “At less than a meter long on average, they’re incredibly cute little animals that do not look like sharks at all,” she adds.

A DNA analysis of skin samples from the live fish suggests that walking sharks broke away from their original population and became a distinct species about nine million years ago. Though that may appear to be a long time ago, it is relatively recent given that sharks have been around for more than 400 million years. In fact, Dudgeon and her team believe walking sharks are the youngest kind of sharks on Earth!

The researchers say that the sharks’ small numbers and small habitat make them extremely vulnerable (易受伤害) to natural disasters and overfishing. They are currently on the Nature Red List, which lists species at risk. Dudgeon and her team believe sensible conservation management plans are urgently needed to protect the walking sharks and other endangered animals from further threats.

【推荐2】The koala is an unusual creature. Native to Australia and a bit bigger than a rabbit, it spends most of its time in eucalyptus trees（桉树），feeding on leaves that are poisonous to nearly every other animal on the planet.

The koala sleeps about 22 hours a day and spends the remainder of its time eating and resting. It might spend 10 minutes a day moving, experts say, usually from one tree to another. It has a soft pad at the end of its spine and extra thick fur on its rear end to make the effort, of sitting more comfortable.

The unique lifestyle of the koala has helped it prosper, but today the cute and iconic creature is facing threats from habitat loss, disease and a changing climate. Koala populations are expected to decline by 50 percent in the next 20 years according to the Australian Museum.

To help protect these animals, which bring in an estimated $1.1 billion to Australia each year through koala-related tourism, an international team of researchers has published the first complete genome（基因组）of the koala. Their hope is that the keys to the marsupial’s（有袋动物）long-term survival might be planted in its genetic code.

“The ultimate goal is that we won’t have to…rescue them from the edge of extinction,”said Rebecca Johnson of the Australian Museum Research Institute in Sydney, who led the work.

“Now we have a really good understanding of the koala genome, and we are in a fantastic position to use that knowledge to help us manage them.”

An elementary analysis of the koala’s genome, published in Nature Genetics, has already yielded some interesting findings.

For example, the authors found that, compared to other mammals, the koala’s DNA includes an expansion in the number of genes that encode for enzymes involved in anti-poison. That allows them to have a diet that depends almost entirely on eucalyplus leaves which are unusually high in poison. However, it also means that koalas metabolize（代谢）medicines like anti-chlamydia antibiotics faster than other animals.

The koala genome also revealed why koalas are such famously picky eaters. They are known to consume leaves from just 20 of Australia’s 60 known eucalyplus species. And even when they are in one of their preferred trees, koalas take leaf selection very seriously.

Johnson said that the information encoded in the koala’s DNA is already being included in management strategies by conservation groups. However, she said the findings described in the new paper represent the early stages of what can be gleamed from the marsupial’s genome.

“The data is public, and I would love for anyone to start mining it and see what other amazing things they can find,”she said.“Once you have a genome of this quality, the sky’s the limit with what you can do with it.”

【推荐3】It is sad to learn that fewer of us now own pets. According to Mintel, just 56% of UK households（家庭）today include a pet, compared with 63% in 2012. It is down to our smaller homes. The housing crisis（危机）is taking away one of our life’s joys: pets.

Pets can help us get over serious illness. Pets lessen our anxiety. Pets can be a godsend for people experiencing various forms of mental disorders. As if all that were not enough, pets also help their owners get a date because of complex psychological reasons.

There do, of course, remain oppositions to the very idea of pets. The charity PET A puts it thus: “This selfish desire to own animals and receive love from them causes immeasurable suffering, which results from selling or giving them away casually, and taking away their opportunity to enjoy their natural behavior.” This is undoubtedly true in some situations. But seen from a different point of view, there’s something quite lovely about the story of people and their companion animals.

What was once a relationship based only on the animal’s functional effects—its ability to kill pests（害虫）, guard houses, and the like—has developed into something much more about care and love.

We share 84% of our DNA with dogs. We share 90% of our DNA with mice, for good ness sake. I have no idea how that works. But still pets remind（提醒）us we’re part something bigger. Pets break down the barriers between us and the animal kingdom. We may teach pets to roll over, stand up, order takeaways and so on. But they teach us much more: that life is actually really quite short and so should be filled as much as possible with life-giving experiences.

【推荐1】Breathing dirty air can cost someone’s lifespan (寿命) months—even years, a new study finds. Worldwide, air pollution lowers average lifespans by a year. Scientists shared their new findings in Environmental Science & Technology Letters.

Air pollution (污染) has been linked to many health problems. Most earlier studies have looked at how tiny air pollutants affected rates of illness or death. But now an environmental scientist, Joshua Apte, is going even further. He works at the University of Texas, Austin. He together with his team is looking at life expectancy, hoping to make the threat easier to understand.

PM 2.5 is what scientists call tiny particles of pollution in the air. Higher levels of PM2.5 can cause health problems and cut months, if not years, from the average lifespan. This analysis shows pollution affects life expectancy in different parts of the world.

The World Health Organization (WHO) recommends limiting PM 2.5 to 10 micrograms (微克) per cubic (立方) meter of air. Apte’s group used data to try to find how this low level would help people. But meeting the WHO standard won’t get rid of health damage from dirty air. That’s because even below 10 micrograms per cubic meter pollution still causes huge risks.

Reducing air pollution could increase life expectancy. The scientists also compared how other threats shorten life spans across the globe. These risk factors included smoking and cancer.

These results show that in poor countries, cleaning up dirty air could greatly increase lifespans. It could have as big an effect as cleaning up drinking water, or curing lung cancer. However, in wealthier countries air pollution shortens life expectancy by less than half a year. All forms of cancer, in fact, shorten the average life expectancy by more than 3.5 years. “Knowing this can really help people or policymakers, decide where to spend their money.” says Kirk Smith.

【推荐2】Light pollution is a significant but overlooked driver of the rapid decline of insect populations, according to the most comprehensive review of the scientific evidence to date.

Artificial light at night can affect every aspect of insects' lives, the researchers said. "We strongly believe artificial light at night — in combination with habitat loss, chemical pollution, invasive species, and climate change — is driving insect declines,” the scientists concluded after assessing more than 150 studies.

Insect population collapses have been reported around the world, and the first global scientific review published in February, said widespread declines threatened to cause a "catastrophic collapse of nature's ecosystems".

There are thought to be millions of insect species, most still unknown to science, and about half are active at night. Those active in the day may also be disturbed by light at night when they are at rest.

The most familiar impact of light pollution is moths (飞蛾) flapping around a bulb, mistaking it for the moon. Some insects use the polarisation of light to find the water they need to breed, as light waves line up after reflecting from a smooth surface. But artificial light can scupper (使泡汤) this. Insects are important prey (猎物) for many species, but light pollution can tip the balance in favour of the predator if it traps insects around lights. Such increases in predation risk were likely to cause the rapid extinction of affected species, the researchers said.

The researchers said most human-caused threats to insects have analogues in nature, such as climate change and invasive species. But light pollution is particularly hard for insects to deal with.

However, unlike other drivers of decline, light pollution is relatively easy to prevent. Simply turning off lights that are not needed is the most obvious action, he said, while making lights motion-activated also cuts light pollution. Shading lights so only the area needed is lit up is important. It is the same with avoiding blue-white lights, which interfere with daily rhythms. LED lights also offer hope as they can be easily tuned to avoid harmful colours and flicker rates.

【推荐3】Ship tourism to Antarctica is on the rise: More than 35,000 tourists are expected to visit Antarctic this summer. In 1992-1993, 6,750 visited Antarctica, according to the Antarctica Treaty. All of this tourism, however, is putting both tourists and the environment in great danger.

Among the tourist ships that visit the continent, the Explorer, a Canadian ship, was one of the first. Put to use in 1969, it was built to carry tourists to Antarctica. Last week, however, it became the first commercial passenger ship to sink beneath the waters. Fortunately, all of the passengers and crew members were rescued from the ship. However, the sunken ship endangered the Antarctic’s fragile(脆弱的) environment. The ship was estimated to be holding 48,000 gallons of fuel.

The accident was not unexpected. Both the US and UK had warned a conference of the Antarctic Treaty member countries in May that the tourism situation in this area was a potential disaster. The US said in a paper, people “should take a hard look at tourism issues now, especially those related to ship safety.” Although the Antarctic seas are relatively calm, floating ice causes a potential threat to ships. The owner of the Explorer blamed the sinking on a fist-like hole in the ship created by ice.

Many of the other large ships now visiting Antarctica are not designed especially against thick ice. Such ships generally can only come to the continent in summer. But the tourist rush is pushing ships into dangerous situations. “The increasing number of ships operating in Antarctic means that the ship are under great pressure to get there in time for the key visiting sites,” the British government wrote in a paper at the meeting of member countries.

As a natural frontier, Antarctica is in a messy legal situation. There are no obvious answers as to who is responsible for dealing with the threat that tourist may cause to human life and the environment.

There is no coast guard for Antarctica. Do we want it to become Disneyland, or do we need some controls?