1 . Female penguins get stranded

Every year, thousands of Magellanic penguins (麦哲伦企鹅) get stranded along the coast of South America, but, _________ about 75% of those that get stuck are female. Now scientists say they have worked out what is behind the gender _________: the females migrate further north than males.

Magellanic penguins finish breeding in Patagonia in February, and, during the _________ winter months, head north, reaching as far as Brazil, in search of anchovies (风尾鱼). But every year thousands become stranded, with many _________ to safety on board military aircraft by human.

Writing in the journal Current Biology, researchers in Japan and Argentina report how they _________ tracking device to eight male and six female penguins in 2017 and tracked where the birds went after they left the breeding grounds of Cabo dos Bahfa in Argentina and began the migration north in April.

Previously it was unknown whether male and female’s took different paths or not. “Although some _________ are made, the exact reason for the _________ stranding has been unknown due to the lack of information on their behavior outside the breeding season.” said Takashi Yamamoto, a co-author of the report from the Institute of Statistical Mathematics in Japan.

The results from the study offer a clearer picture. _________ the authors note that only a small number of penguins were tracked, all the female’s generally traveled further north. The male, meanwhile, predominantly stuck to waters of the Argentinian coast. The study also found male _________ dived deeper than female’s: about 59 metres compared with about 35 metres.

The authors offer a number of reasons why males and females may head to different areas— including to avoid __________ for food—and why they dive to different __________ —the females’ smaller bodies may restrict the depths they can reach. They also suggest the different sexes may seek waters of different temperatures, with the __________ females preferring warmer, shallower surroundings.

While researchers are still trying to understand why penguins end up stranded, Yamamoto and colleague’s suggest those that end up further north may have used more energy swimming or catching __________ prey, leaving them exhausted. Climate change, pollution in the area or injury from fishing equipment could also play a role. Reports of standings have noted that many penguins are unwell or exhausted, with some even washing up dead.

“__________, plastic remains have been reported in the stomach of beach-washed Magellanic penguins,” said Yamamoto, adding that a stewed sex ratio could potentially lead to a population decline.

While the findings may not help prevent strandings, Yamamoto said it could help with __________ of the species. “If we do not consider any action, such as marine zoning, I expect that the number of stranding individuals will increase.”

2 . Otters, are cute, this no one can deny. They have big eyes, short and flat noses and claws (爪子) like tiny hands. They look even cuter when they wear hats and throw food balls into their mouths as if they were bar snacks, like Takechiyo, a pet otter in Japan. Documenting Takechiyo’s funny behavior has earned his owner nearly 230,000 followers on Instagram, a photo-sharing app.

Takechiyo’s fame reflects a craze across east and South-East Asia for keeping the cute creatures as pets. Enthusiasts in Japan visit cafés where they pay to hug them; Indonesian owners parade their pets around on leads or go swimming with them, then share their pictures online. But these enjoyable photos mask a trade that is doing a lot of damage. Even before they became fashionable companions for humans, Asia’s wild otters faced plenty of threats. Their habitats are disappearing. They have long been hunted for their coats, or killed by farmers who wish to prevent them consuming fishes. The pet trade, which began picking up in the early 2000s but appeared to speed up a few years ago, has made things worse. The numbers of wild Asian small-clawed otters and smooth-coated otters, two species that are in highest demand, have declined by at least 30% in the three decades to 2019.

The international agreement that governs trade in wildlife, known as CITES, now prohibits cross-border trade in these species. But laws banning ownership are often poorly implemented, as in Thailand, or full of holes, as in Indonesia. And the otter-keeping craze has been dramatically improved by the internet, says Vincent Nijman of Oxford Brookes University. In 2017 TRAFFIC, a British charity that monitors the wildlife trade, spent nearly five months looking at Facebook and other social-media sites in five South-East Asian countries. During that time, it found around 1,000 otters advertised for sale online.

In any case, otters do not even make particularly good pets. Every year the Jakarta Animal Aid Network, a charity in Indonesia’s capital, receives some ten otters from people who have struggled to look after them. Faizul Duha, the founder of an Indonesian otter-owners’ group, admits that his two animals emit a “very specific” (read: fishy) smell. They bite humans and chew on furniture. Their scream can be heard blocks away. And their cages need cleaning every two-to-three hours. That is how often they empty their bowels (肠道).

Urban Trees Are Threatened by Climate Change

By 2050, about three-quarters of the species will be at risk as a result of climate change, a study has found. Cities around the world may need to start planting different types of trees and shrubs that can     1     warmer and drier conditions.

“By ‘at risk’, we mean these species might be     2     stressful climatic conditions,” says Manuel Esperon-Rodriguez at Western Sydney University in Australia. “Those trees are likely to die.”

City trees have many benefits, from making urban spaces look beautiful and providing a refuge for wildlife to keeping places up to 12°C cooler than they would otherwise be in summer. Losing tree     3     would lead to cities becoming even hotter as the planet heats up.

To     4     the threat, Esperon Rodriguez and his colleagues used database called the Global Urban Tree Inventory to work out the conditions required by 3100 tree and shrub species currently grown in 164 cities worldwide. The researchers then looked at how these conditions would be affected by climate change under medium-emissions scenario known as RCP 6.0.

By 2050, 76 per cent of these species will be at risk from rising     5     temperatures and 70 percent from decreasing rainfall, the team concludes.

The study doesn’t take account of       6     urban growth, which could warm cities even faster. Nor does it take account of greater weather     7     caused by climate change, or the effects of pests and diseases. Warmer conditions are allowing more pests, such as bark beetles, to survive winters as well as to reproduce faster in summer, greatly increasing their     8    .

“Our     9     have scientific basis,” says Esperon-Rodriguez. There are some things that can be done to help trees survive. The best strategy is to choose tough species when     10     trees or planting new ones, the team concludes.

Children Raised in Greener Areas Have Higher IQ

Growing up in a greener urban environment boosts children’s intelligence and lowers levels of difficult behaviour, a study has found.

The analysis of more than 600 children aged 10 to 15 showed that a 3% increase in the greenness of their neighborhood raised their IQ score     1     an average of 2.6 points. The effect was seen in both richer and poorer areas.

There is already significant evidence for green spaces’ effects on improving various aspects of children’s cognitive development but this is the first research     2     (examine) IQ. The cause is uncertain but may     3     (link) to lower stress levels, more play and social contact or a quieter environment.

The increase in IQ points was particularly significant for those children at the lower end of the spectrum,     4     small increases could make a big difference, the researchers said.

“Evidence has built up over time     5     green surroundings are associated with improved cognitive functioning, such as memory skills and attention,” said Tim Nawrot, a professor of environmental epidemiology at Hasselt University in Belgium, where the study was conducted.

“    6     this study adds by including IQ is a more rigorous, well-established clinical measure. It is really of value to create an optimal environment for children to develop their full potential,     7     is why I think city builders or urban planners should prioritize investment in green spaces.”

The study, published in the journal Plos Medicine, used satellite images to measure the level of greenness in neighborhoods, including parks, gardens, street trees and all other vegetation.

The average IQ score was 105 but the scientists found 4% of children in areas with low levels of greenery scored below 80,     8     no children scored below 80 in areas with more greenery.

The benefits of more greenery     9     (record) in urban areas were not replicated in suburban or rural areas. Nawrot suggested this might be because those places had enough greenness for all children living there to benefit.

Behavioral difficulties such as poor attention and aggressiveness were also measured in the children     10     (use) a standard rating scale, and the average score was 46. In this case, a 3% rise in greenery resulted in a two-point reduction in behavioral problems, in line with previous studies.

9 . Gone are the days when big businesses were looked upon by environmentalists as enemies in the fight against global warming.

Just two weeks after U. S. President Donald Trump pulled his country out of the Paris Climate Agreement, more than 900 American firms put their _______to a “We Are Still In” open letter to the United Nations. Together, they promise to help reduce America’s carbon emissions by 26 percent by 2025, _______the Paris Climate Agreement.

_______, big businesses have been taking climate change seriously for years now. Alongside energy-efficiency measures, the strongest evidence of their _______has been the number of new wind and solar projects that they have been helping to build around the world. IT firms such as Amazon and Google have been using clean energy to power their servers (服务器). Some environmentalists now believe that big businesses could become strong _______behind the worldwide spread of renewable energy. “There used to be little action,” says Marty Spitzer of the World Wildlife Fund (WWF), “Now, I see fundamental _______being made.”

More recently, this enthusiasm for environmental protection has _______from corporate headquarters to branches and suppliers, and from developed countries to emerging markets. Take Walmart, the world’s largest retailer, for example. In March 2016, it said that it would require its own operations and those along its _______chain to reduce carbon-dioxide emissions by one billion tons by 2030. This is _______to taking 211 million passenger cars off America’s roads for a year. The announcement was ________by the WWF and other conservation organizations, which are helping Walmart’s suppliers work towards this goal. Apple, maker of the iPhone, has said that seven of its biggest global manufacturers have promised to power their Apple-related ________with renewable energy by the end of this year.

According to the WWF, in the United States alone, nearly two dozen of the biggest firms have committed themselves to becoming 100 percent renewable in the near future. Hervé Touati of the Rocky Mountain Institute, a clean-energy research firm, explains the ________behind this trend. Going green improves the companies’ public image and helps attract customers, staff and investors.

Anheuser-Busch InBev, the world’s biggest brewer (啤酒公司), has lots of young people among its many ________. Many of them take environmental issues seriously. Electricity, used ________in the brewing process, amounts to a tenth of its total costs. Last year, the company set out to increase the role of renewables in generating ________to 100 percent by 2025. “My generation often takes energy and clean air for granted,” said Tony Milikin, the firm’s chief sustainability officer. “The generation coming up now looks at it totally differently.”

10 . The colours of beautiful feathers are often borrowed. Flamingos, for example, owe their pinkness to chemicals called carotenoids that are made by bacteria known (confusingly) as blue-green algae. The birds, when feeding, both ingest these bacteria directly and consume small crustaceans (甲壳纲动物) that themselves live on such bacteria､Blue-footed boobies obtain their eponymous colour similarly, via the fish they eat.

Carotenoids, though, are dual-use molecules. Besides giving these birds colours, they also help to stimulate the immune system. If a bird has some health issues, its immune system will thus use up some of its carotenoid stock defending against these interlopers, and its colour will suffer. If it is in good shape, by contrast, most of the carotenoids it consumes will be used to create colour. This is a difference that potential mates notice and act on, as dozens of experiments have proved. But a study just published in Naturwissenschaften has gone beyond these observations and shown that bright feather is also an indicator of a healthy digestive system.

Wild animals live in a world of constant food scarcity. Squeezing every last calorie and nutrient molecule from what they eat is crucial to their survival. Since carotenoids are obtained as part of this digestive process. Tuul Sepp of Arizona State University and her colleagues wondered if feather brilliance might therefore be a reliable signal of the efficiency with which a bird draws goodness from its food.

To assess that she turned to a test called the “acid steatocrit”. This involves collecting an animal’s faeces(排泄物) mixing them with perchloric acid to liberate the fat molecules within, centrifuging(使离心) the mixture and then measuring the thickness of the fatty layer which has accumulated at the top. The thinner this layer, the more efficiently the animal in question has been digesting any fats it has eaten. Since most carotenoids are bound to fatty molecules called lipoproteins, Dr Sepp reasoned that those birds which the test suggests are collecting fats efficiently from their food will also be brightly coloured.

To investigate this idea, she and her colleagues collected 36 male house finches—birds known for having brilliant red breasts. They photographed their captives and held them in cages for a short time, in order to collect some faeces from each. They then ran the images of the birds ‘breasts through a computer to analyse how red they were, and studied a sample of each bird’s faeces using the acid stratocrat test.

The result was that there is indeed a correlation between the brilliance of a bird’s breast and the efficiency of its fat digestion. If Dr Sepp’s computer can see this, it seems likely female house finches can, too—and will thus have yet another reason to pick the mates with the prettiest feathers.