Along the river banks of the Amazon and the Orinoco there lives a bird that swims before it can fly, flies like a fat chicken, eats green leaves, has the stomach of a cow and has claws(爪)on its wings when young. They build their homes about 4.6m above the river, an important feature(特征)for the safety of the young. It is called the hoatzin.

In appearance，the birds of both sexes look very much alike with brown on the back and cream and red on the underside. The head is small, with a large set of feathers on the top, bright red eyes, and blue skin. Its nearest relatives are the common birds, cuckoos. Its most striking feature, though, is only found in the young.

Baby hoatzins have a claw on the leading edge of each wing and another at the end of each wing tip. Using these four claws, together with the beak(喙), they can climb about in the bushes, looking very much like primitive birds must have done. When the young hoatzins have learned to fly, they lose their claws.

During the drier months between December and March hoatzins fly about the forest in groups of 20 to 30 birds, but in April, when the rainy season begins, they collect together in smaller living units of two to seven birds for producing purposes.

In Australia, the bilby (兔耳袋狸) project is seen as an important part in protecting the nation’s wildlife. Bilbies are known for their long ears and large back legs. They usually sleep during the day, and are awake at night. They look a lot like rabbits and grow to about 2.5 kilograms.

For the first time in 2018, bilbies are running wild in Southeastern Australia. The small animals were once widespread across much of Australia, but were last observed in the wild in New South Wales state in 1912. Every year bilby populations continue to decrease. Wildlife experts are afraid that the bilby, a small marsupial, could eventually disappear forever, either because of land clearing or fires. Another reason is a threat from cats and foxes, which hunt down and kill bilbies.

In northern New South Wales state, environmentalists are celebrating what they are calling a historic moment. Thirty bilbies from a captive breeding program have been released into a large predator-free enclosed area north of Sydney. Without the protection of a 32-kilometer fence, experts say the animals probably would not survive.

Tim Allard heads the Australian Wildlife Conservancy, which is involved in the project. He says the release of these beloved animals is a big deal. “There are some remaining wild bilby populations, but they get predated upon heavily by feral cats and foxes. Bilbies only really survive behind fenced areas.” Allard said the point of doing this project is to return the countryside to what it used to be before Europeans arrived. “So in the not-too-distant future, you will be able to go inside the fenced areas and it will be like stepping back before Europeans turned up,” he said.

Deep within an Indonesian rainforest, a team of research scientists recorded something: a Sumatran orangutan (红毛猩猩) named Rakus carefully treating a cut on his cheek with a medical plant. “This is the first observation of a wild animal doing so,” said Isabelle Laumer, a primatologist at the Max Planck Institute of Animal Behavior in Germany.

The rainforest surrounding the research center is home to the highest density of Sumatran orangutans. One June morning in 2022, the researchers there observed that Rakus had suffered a wound under his right eye. Because he had wandered outside of the research area, no one witnessed how the injury occurred though the researchers have two hypotheses (假设).

One is that Rakus fell from a tree and got hit by a branch. Because Sumatran orangutans spend about 98 percent of their time in trees, they sometimes grab dead or dying branches that can’t hold their weight. The other possibility is that Rakus was wounded during a fight with another Sumatran orangutan. Fights within this region of the rainforest are rare but can occur when males try to establish dominance (统治地位).

Regardless of how the injury occurred, the team observed Rakus climbing plants called Akar Kuning, commonly used by humans as treatment for wounds and illnesses like malaria (疟疾). Rakus removed the leaves from the plant and chewed them. He then repeatedly put the liquid he extracted from the plant directly onto his wound. Afterward, he placed a solid part of the leaf over the area. Incredibly, the next day he returned to eat the plant again. Three days later, the wound closed. Within a month, its scar was barely noticeable.

“It could be that he was just feeding on the plant and then accidentally touched his wound with the hand that had been touching it and its pain-relieving properties were immediately felt so he applied it to the area again and again,” said Laumer.

“This new finding highlights the adaptive intelligence of these animals in natural environment, making us know animal behavior, medicinal plant use, and the potential development of human medicine,” said Ina-Vandebroek, a senior lecturer at the University of the West Indies in Jamaica.