1 . How can having a childlike view of the world help the environment? Danish eco-artist Thomas Dambo combines a talent for recycling with a fairy-tale imagination to bring people worldwide closer to nature.

For the “Guardians of the Seeds” exhibition, Danish eco-artist Thomas Dambo built five trolls from discarded wood materials, which were appointed by Coastal Maine Botanical Gardens (CMBG) for its splendid riverside woodland.

The exhibition composed of the five trolls aims to give visitors an emotional connection with nature that will encourage them to become keepers of it. For the exhibition, Thomas came up with a story that a family of trolls hid 10 golden seeds to protect the old forest. Using a map that's provided, visitors follow clues to find where the seeds are hidden.

Besides using carefully selected recycling materials to produce his works, to challenge himself creatively, the artist allowed for a degree of production on-site. He gave a skinny troll named Birk a beard made from the roots of fallen trees. The fur of another troll Roskva is made from bark. Also, Gro, sitting with her eyes closed in a yoga pose, has a tongue made out of a nearby deserted planter.

“Thomas wants people to interact with them,” says Gretchen, president of CMBG. “He wants it to be a journey of discovery where you're walking along and all of a sudden this big magical being appears in front of you. These are friendly, happy trolls. They're not scary, mean trolls.”

Thomas hopes that “Guardians of the Seeds” gives viewers the same joy he gets from an occupation that he compares to a hobby. He says too many people lose their playfulness in their adult life. The key quality of his work is just its playfulness. One of his trolls sits on a real car on a hillside, appearing to cheerfully ride it. He wants to reactivate a childlike imagination in adults so they begin to see trash as objects that can be repurposed in practical and even picturesque ways. And he loves to entertain kids, too.

Nowadays, Mr. Dambo gets a kick out of seeking waste everywhere, hoping to find more stuff he could refashion into something amazing.

2 . Satellite imagery like Google Earth makes it easy for ecologists halfway around the world to check up on tropical forests—see illegal roads and logging (伐木), for example. But the information is limited.

“Satellite data often tells you what happens after it's happened.” Rhett Butler said, the founder of Mongabay. com, an environmental science news website. In a perspective piece in the journal Science, he and his colleagues write that sound recordings can supplement satellite data as another conservation tool.

You can actually set up alerts. So you can hear things like chainsaws (电锯) or gunshots in real time. So you can get put ahead of potential deforestation before it occurs. Small audio recorders, some of which are solar-powered and connecteded to cellphone grids for data upload, also give ecologists the ability to listen secretly on a jungle's biodiversity over time.

If you're in a primary forest, you'll tend to see all the frequencies of the soundscape occupied by different species. These are insects, birds, calling mammals, frogs things like that.”

As a comparison, here is a forest plot after selective logging---meaning some trees were cut, others left standing. “As you move into a more disturbed ecosystem, you'd start to see more gapsacross the frequencies of that soundscape.”

Certain insects dominate. And the diversity of calls declines as disturbance increases. While the human ear is perceptive (感知的), algorithms (运算法则) are a much more powerful tool to comb through thousands of hours of data, to get a richer picture of changing tropical biodiversity.

Nowadays, many industries---like cattle farming, palm oil, soybean and paper production are committing to zero deforestation goals, which can be hard to measure. But by coupling satellite data and camera traps with audio recordings, ecologists can keep their eyes-and ears-on what's going on in the jungle.

3 . One billion people in the world are short of water. How can this problem be solved. Some suggestions have been to desalinate ocean water or to build enormous water pipelines from areas where water is abundant. (Suggestions such as these prove extremely expensive when they are actually used.) One possibility that scientists are considering is pulling icebergs from either the North Pole or the South Pole to parts of the world with a water shortage. Although many questions must be answered before such a project could be tried, moving icebergs seems a reasonable possibility in the future.

Engineers, mathematicians, and glaciologists from a dozen countries have been considering the iceberg as a future source of water. Saudi Arabia is particularly interested in this project because it has a great water shortage. Scientists estimate that it would take 128 days to transport a large iceberg (about 1/2 square mile) to Saudi Arabia. Yet the iceberg would be completely melted by the 104th day. Therefore, insulation would be essential, but how to insulate the iceberg remains an unsolved problem.

The problems in transporting an iceberg are numerous. The first problem is choosing the iceberg to pull. The icebergs that form in the North Pole are quite difficult to handle because of their shape. Only a small portion extends above the water — most of the iceberg is below the surface, which would make it difficult to pull. South Pole icebergs, on the other hand, are flat and float like table tops. Thus they would be much easier to move.

How can a 200-million-ton iceberg be moved. No ship is strong enough to pull such enormous weight through the water. Perhaps several ships could be used. Attaching ropes to an iceberg this size is also an enormous problem. Engineers think that large nails or long metal rods could be driven into the ice. What would happen if the iceberg splits into several pieces during the pulling. Even if an iceberg with very few cracks were chosen, how could it be pulled through stormy waters. Furthermore, once the iceberg reached its destination, very few ports would be deep enough to store it.

All of these problems must be solved before icebergs can become a reasonable source of water. Yet scientists estimate that it will be possible to transport them in the near future. Each year, enough icebergs form to supply the whole world with fresh water for a full year. In addition, icebergs are free and nonpolluting. As a solution to the world’s water problems, icebergs may be a workable possibility.

4 . Most animals living in crowded conditions have particularly strong immune systems, so it long puzzled researchers that honeybees do not.

Part of the answer, discovered in 2015, is that queen bees vaccinate their eggs by moving parts of proteins from disease-causing pathogens to them before they are laid. These act as antigens to trigger the development of a protective immune response in the developing young. But that observation raises the question of how the queen receives her antigen supply in the first place? Dr. Harwood wondered if the nurse bees were taking in parts of pathogens and passing them to royal jelly they were producing while eating the food brought to the hive.

To test this idea, he teamed up with a group at the University of Helsinki, in Finland, led by Dr Heli Salmela. Together, they collected about 150 nurse bees and divided them among six queenless mini hives equipped with baby bees to look after. Instead of honey, they fed the nurses on sugar water, and for three of the hives they added P. larvae, a bacterium causing a hive-killing disease, to the sugar water.

In this case, to stop such an infection happening, Dr Harwood and Dr Salmela heat-treated the pathogens and so killed them in advance. They also labelled the dead bacteria with a fluorescent dye, to track them easily. And, sure enough, it was confirmed that parts of P. larvae were getting into royal jelly released by those bees which had been fed with the sugar water containing that.

All told, these findings suggest that nurse bees are indeed, through their royal jelly, passing antigens onto the queen for vaccinating her eggs. They also mean the nurses are vaccinating baby bees as well, because baby bees, too, receive royal jelly for the first few days after they come out.

“Animals are a who, not a what,” animal advocates say. Animal rights activists, including Jane Goodall, want writers —     1     take guidance from the Associated Press Stylebook — to stop referring to an animal as “it.”

Animals are a part of some of the most important     2    （story）being told right now, but they are not always given     3     voice. We have learned much about how intelligent, social, complex and unique as individuals they are, and we know they are important. But many times, they     4    （describe）as if they are merely objects whose lives and interests don't deserve further     5    （consider）on our part.

Jane Goodall points out that when she     6    （start）her research, she was told that her findings and approaches, such as     7    （give）names to chimpanzees, were wrong. She was told that the belief that they have emotions was also     8    （correct）.

“But we know that animals feel joy, pain     9     grieve; We are not separate     10     other species,” Goodall adds. We must recognize that every individual nonhuman animal is a ‘who,' not a ‘what.'

7 . Poaching and habitat loss have threatened Africa's two species of elephants, taking them closer toward the edge of disappearance, according to a new report released by the International Union for Conservation of Nature(IUCN).

Before this update, Africa's elephants were grouped together and were evaluated as vulnerable by the IUCN. This is the first time the two species have been sorted separately. In the past, elephants were mostly considered as either Asian elephants or African elephants. Forest and savanna elephants were typically classified as subspecies of African elephants.

The African forest elephant is now listed as critically endangered and the African savanna elephant as endangered. The number of African forest elephants fell by more than 86% over a 31 -year assessment period. The population of African savanna elephants dropped by at least 60% over the last 50 years, according to the IUCN, which tracks the assessment risk of the world's animals. Africa currently has an estimated 415,000 elephants, counting the two species together.

Both elephant species experienced significant population decreases because of poaching. Although it peaked in 2011, illegal hunting still happens and continues to threaten elephant populations. African elephants also face continued habitat loss as their land is converted for agriculture or other uses.

There is some good conservation news, the IUCN points out. Anti-poaching measures, combined with better land use planning to support better human-wildlife relationships, have helped conservation efforts. Some forest elephant population figures have stabilized in well-managed areas in Gabon and the Republic of Congo and savanna population figures have remained stable or have been growing, particularly in the Kavango-Zambezi Transfrontier Conservation Area in southern Africa.

But with constant demand for ivory and increasing human pressures on Africa's wild lands, concern for Africa's elephants is high, and the need to creatively conserve and wisely manage these animals and their habitats is more severe than ever.

8 . Britain's brilliant bridges have supported trade, brought communities together and are always the most exciting part of the journey. These must-see bridges are now tourist attractions in their own right.

Clifton Suspension Bridge, Bristol

Described by its legendary engineer Isambard Kingdom Brunel as “my first love, my darling", it was originally designed for horse-drawn traffic. Now, more than four million vehicles a year cross the 1,352ft-long toll （通行费）bridge over the Avon Gorge. The £ 1 toll for every journey pays for its maintenance. The history of the bridge, dating back to 1864, is kept alive through a programme of tours, events and exhibitions.

Infinity Bridge, Stockton-On-Tees

A pedestrian（行人）and cycle footbridge across the River Tees, its working title was the North Shore Footbridge, before it was given its grander name when opened in 2009. It is particularly incredible at night. The arches（拱形）of the bridge are also lit white and, on calm nights, their reflection in the water appears as an infinity（无穷大）symbol, thus inspiring the name which was chosen by the public.

Tower Bridge, London

An engineering wonder built from thousands of tons of Portland stone and steel, it took construction workers eight years to complete. More than 120 years old, it's a popular tourist attraction, as well as a functional bridge. Visitors can take in the views over the capital, experience seeing London life through the Glass Floor, and visit the Victorian Engine Rooms.

Iron Bridge, Shropshire

Opened in 1781 , this is the first arch bridge in the world made out of cast iron. Recognised as one of the great symbols of the industrial revolution, it transformed the craft of bridge building and was a crucial factor in the development of the iron trade in Shropshire.

9 . One of the greatest challenges in caring for such intelligent animals as chimpanzees (猩猩) is providing them with enriching experiences. Every day, the chimpanzees at Project Chimps receive morning and evening food-based enrichment devices, but caregivers are always looking for more ways to keep the chimps mentally engaged. With 79 chimpanzees, each with their distinctive personality, care staff often find that different chimps react differently to new enrichment.

Last year, we began inviting musicians to perform for chimps to see what they may respond. A violin performance received quite the response. Additional musicians were lined up to visit but the coronavirus has stopped the activities, which we hope to resume in the near future.

This past week, we brought an electric piano for the chimps to investigate. Some chimps, like twins Buttercup and Clarisse, were immediately interested and could not wait to tap out a few notes. Others, like Emma, were more interested in trying to take it apart.

29-year-old Precious has very little tolerance for the piano. She sat off to the side for a few minutes, but eventually she decided that was enough. She called an end to the enrichment session by throwing a handful of waste at the piano. Receiving her message loud and clear, we removed the piano.

We could never have guessed how 33-year-old Luke would react to it. As with many retired lab chimpanzees, Luke has some anxiety issues. He seems particularly distrustful of anything new, including people, food, and enrichment. But when we presented the chimps with the piano, Luke was the first to investigate. We could not believe our eyes—this usually anxious chimpanzee bravely chose to explore something new!

To us at Project Chimps, this is what it is all about: giving chimpanzees the freedom to choose. We are honored to be part of their journey.

10 . When you walk on a sandy beach, it takes more energy than striding down a sidewalk — because the weight of your body pushes into the sand. Turns out, the same thing is true for vehicles driving on roads. The weight of the vehicles creates a very shallow indentation (凹陷) in the pavement (路面) — and it makes it such that it’s continuously driving up a very shallow hill.

Jeremy Gregory, a sustainability scientist at M.I.T. and his team modeled how much energy could be saved — and green-house gases avoided — by simply stiffening (硬化) the nation’s roads and highways. And they found that stiffening 10 percent of the nation’s roads every year could prevent 440 megatons of carbon dioxide equivalent emissions over the next five decades — enough to offset half a percent of projected transportation sector emissions over that time period. To put those emissions savings into context — that amount is equivalent to how much CO2 you’d spare the planet by keeping a billion barrels of oil in the ground — or by growing seven billion trees — for a decade.

The results are in the Transportation Research Record.

As for how to stiffen roads? Gregory says you could mix small amounts of synthetic fibers or carbon nanotubes into paving materials. Or you could pave with cement-based concrete, which is stiffer than asphalt (沥青).

This system could also be a way to shave carbon emissions without some of the usual hurdles. Usually, when it comes to reducing emissions in the transportation sector, you’re talking about changing policies related to vehicles and also driver behavior, which involves millions and millions of people — as opposed to changing the way we design and maintain our pavements. That’s just on the order of thousands of people who are working in transportation agencies. And when it comes to retrofitting (翻新) our streets and highways — those agencies are where the rubber meets the road.