Coral reefs (珊瑚礁) are among the most productive ecosystems in the world. They’re also in serious danger——climate change and other threats are killing them off. But researchers have come up with an invention they think could help the reefs: 3D-printed corals.

At the heart of reef ecosystems lies a symbiosis (共生关系) between corals and algae (藻类). Corals use light and they’re photosynthesizing (光合作用). The algae inside corals’ tissues (组织) make use of the light to generate energy, and that energy is then transferred to the coral animal host. That animal host, in return, transfers certain by-products to the algae, so they have a symbiosis going on.

This bond between algae and corals is what makes reefs so incredibly productive.Because of this symbiosis, corals have evolved complex skeletal (骨骼的) and tissue structures for collecting sunlight which usually fades rapidly. Through the skeleton, light is pumped and guided into deeper, otherwise shaded areas.

Scientists copied some tricks that corals use. They imaged corals to analyze their skeletal and tissue makeup and then used a 3D bioprinter to build a complicated structure that mimics real corals. The printed corals were made of biomaterials like cellulose (纤维素) and had algae planted in them.

The researchers replicated (复制) coral structure so well that the algae grew very quickly—— up to 100 times more densely than they normally grow in the lab. The 3D-printed creation could be used as a medium to grow algae to produce bioenergy and also as a tool for studying the coral-algae symbiosis.

Of course, there are many other ways this technology can be further scaled and improved to create something like artificial corals in the future. So this is just the first step,where they created the animal host, but they are now continuing to further replicate this animal-algal symbiosis and developing model systems. Eventually, it would be nice that this can have direct applications in coral reef restoration.

In March 2020, 16 wild Asian elephants left their natural habitat in Xishuangbanna, Yunnan. They then headed north and returned home in September 2021. 【小题1】 Short videos on social media platforms offered people the most up-to-date information on the herd’s (兽群的) movements.

Unlike the online viewership, the Yunnan Provincial Government remained on edge. 【小题2】 Therefore, the provincial authorities established a new headquarters including forestry and grassland,emergency management, and public security personnel to organize a flood of human and material resources to track the elephants 24/7. Members helped with choosing safer routes or better timing and avoided having the animals crash into heavily populated areas by applying soft and flexible methods, like leaving food for them along the desired route.

【小题3】 But the staffs work would continue back at headquarters as they were in charge of predicting where the brave visors would head the next day and design their plans.

【小题4】 As local governments released news of their incoming well in advance, families would hide on the rooftops or squat down in the safety zone to watch from afar. Some villagers even brought corn to the headquarters, worried the elephants didn’t have enough to eat. Upon uncovering open farming fields, the wild animals would rush in and dive into a food fest. 【小题5】

Although scientists and officials have yet not discovered the reasons for the move, the 500-day round trip showed the importance both the Chinese government and people attach to wildlife, environment and biodiversity conservation.

With the aim of educating both locals and visitors about Arctic animals and the value of preserving Norway's natural heritage. Bardu's Polar Park offers encounters(邂逅) with hand raised wolves.

I stood nervously outside the enclosure(圈地) at Polar Park. Somewhere behind the wire were five Norwegian grey wolves. "These are just big dogs," I kept saying to myself. “And they probably have had breakfast already.”

Stig Sletten, Polar Park's animal manager, said,' "Once you’re in with the wolves, lie down and don't stare them in the eye. Let them approach you. Don't stick your hands out. And absolutely don't stick your tongue out." That we were about to enter a cage full of “socialized” wolves was all down to Stig and his devoted team. It was Stig who founded Polar Park back in 1994. And it was Stig and his team who hand-raised the park's wolves from birth.

“These wolves have all been brought up to be comfortable among humans,” he explained. “Allowing them to meet visitors is actually a good way to reduce boredom and stress” Confident that we understood the strict rules of interacting, Stig opened the enclosure and we all followed him. Within seconds the pack was running rewards us, eyes forward, long noses down. For an exposed human, the first approach of five grey wolves, socialized or not, was a slightly unrest and heart-quickening experience.

But any sense of trepidation was quickly replaced by delight. The five wolves turned out to be fun and curious, and eager to check us out as we were them.

“Most people consider wolves unapproachable. There are a lot of negative or unpleasant impressions about wolves, both in Norway and across the world." said Stig. "One of our main aims here is to educate both locals and visitors about Arctic animals. Once they've got touch with the wolves of Polar Park, many of our visitors leave with a different view. ”