【推荐1】The victims were carried in one by one, their paws and fur burned, suffering from lack of water and fear. Their caretakers bandaged their wounds and laid them in baskets with the only thing that was familiar -- the leaves of a eucalyptus (桉树) tree.

As catastrophic fires have burned more than 2 million acres in Australia, dozens of koalas have been rescued from smoky and burning trees and ashen ground. "They are terrified," said Cheyne Flanagan, clinical director of the Koala Hospital in Port Macquarie, the only facility of its kind in the world.

Koalas, unlike kangaroos, birds or snakes, do not flee from fires but instead climb trees to the top, where they can curd themselves into a ball for protection and wait for the danger to pass. But during high-intensity fires, such as those that have burned in recent weeks, the animals, conservationists said, are far less likely to survive. Even if the fire itself does not reach the tree top, the animals may overheat and fall to the ground, where they can be burned to death.

The suffering of the koala -- a national symbol of Australia -- has raised questions among conservationists and scientists about what it will take to preserve biodiversity in a country increasingly prone to intense fire, extreme heat and water shortage. While koalas have evolved to exist alongside wildfires, the animals are facing new threats not just from climate change but also from human development, which has affected local populations, impairing their ability to survive fires.

"We have these unique animals not found anywhere else on this planet, and we're killing them," Flanagan said. "This is a big wake-up call."

【推荐2】I’m a New York City firefighter. Every day, I see terror — sometimes even death. But the day I found Scarlett was different. That day I saw life. And love.

We were responding to a call about a burning garage. Outside, I heard the sound of cats crying. I couldn’t stop — I would have to look for the cats after the fire was put out.

It took a long time to finally bring the big fire under control, but we did it. No one inside was hurt.

At that point I was free to investigate the cat noises. There was still a lot of smoke and heat coming from the building. I followed the meowing (猫叫) to a spot. There, crying and huddled (挤作一团) together, were five terrified kittens.

I wanted to find the mother. It was obvious that she had gone into the burning garage and carried out all of her babies, one by one — unbelievable.

We finally found her. She was badly burnt. She could barely move. I picked her up, and she relaxed in my arms. Sensing her trust, I shed a tear. I was determined to save this brave little cat and her family.

About a week later, I found out she was going to live. One of the technicians suggested we name her Scarlett, because of her reddened skin.

Knowing what Scarlett endured (忍受) for her kittens, it melted my heart to see her reunited with them. She touched each of them again, nose to nose, to make sure they were all safe. She had risked her life five separate times — and it had paid off. All of her babies had survived.

As a firefighter, I see heroism (英雄事迹) every day. But what Scarlett showed me that day was the kind of bravery that can only come from a mother’s love.

【推荐3】By four months of age, the cognitive performance of ravens in experimental tasks testing their social   intelligence and understanding of the physical world parallels that of adult great apes according to a new study.

Previous studies have demonstrated impressive cognitive abilities in ravens. These birds are capable of considering the visual perspective of others, planning for the future, and insightful problem-solving. Ravens have even been called “feathered apes”. But can they really compare with, primates when it comes to higher cognition?

To put this question to the teal, Pika and colleagues adapted a battery of experimental tests designed for primates to meet the needs or ravens. They include both physical and social cognitive skills. Physical cognitive skills include special memory, understanding relative numbers and addition, and causal reasoning, while social cognitive skills include social learning, communication, and theory of mind.

Pika and colleagues conducted their tests with eight hand-raised ravens. The researchers found that, at four months old, ravens already possessed a full-blown set of cognitive skills and did not significantly change over the time period investigated.

Comparing the performance of the ravens with chimpanzees, Pika and colleagues found that, with the exception of special memory, the ravens' performance equalled that of the great apes. The findings strengthen the idea that ravens, like great apes, have evolved general, flexible cognitive skills, rather than being highly specialized in a few ones only.

However, the researchers caution that the performance of these eight ravens may not be representative of the species as a whole. The birds in this study were tested by two highly familiar people who had hand-raised them. Such socialization factors could affect how the birds perform in cognitive tests designed and administered by humans.

【推荐1】Robert Jarvik, born on May 11, 1946 in Michigan and raised in Stamford, is a medical scientist and researcher, who played an important role in the invention of the artificial heart. He was interested in medicine from a young age. He watched his father perform operations and gained a patent (专利权) for a machine applied in the medical operation before he graduated from high school.

Jarvik attended Syracuse University and considered a career in art. When his father developed heart disease suddenly, he decided then to work on a medical career. He applied to medical schools, but was not admitted to any schools in the US. Before long, he was admitted to the medical school in Italy and stayed there for two years. He returned to get a degree in medicine from New York University in 1971.

After working for a period of time, Jarvik got a job in the organ transplant (器官移植) program at the University of Utah in 1972. He worked with the director of the program, Willem Kolff, who invented the kidney dialysis (肾透析) machine.

By the time Jarvik came to the University of Utah, the organ program had already developed the primary artificial heart. He improved it by creating a diaphragm (横膈膜),which solved many issues with the heart. Eventually, he created the first artificial heart in 1981, the Jarvik-7, to be placed in a human patient, which was considered one of the most important inventions in human history.

Barney Clark, a retired dentist suffering from serious heart disease, received the Jarvik-7 transplant on December 2, 1982. He lived for 112 days after the operation, but the transplant was considered a success. Though receiving criticism for the risk referred to transplant an artificial heart, the Jarvik-7 still became very important for patients who were waiting for a heart. In 1987, Jarvik moved to New York City and formed Jarvik Research Inc. He began developing a new heart — the Jarvik 2000.This smaller machine fits inside a patient’s heart rather than replacing the entire organ.