Every day Mengel, a 67-year-old woman, wakes up and puts on her man-made leg. Then, Mengel does the same for Lola-Pearl, her five-year-old cat.

Mengel has many cats. Most of them have disabilities (残疾). But Lola-Pearl is special. She is a treatment cat. And, she and Mengel are partners of a kind. They are among 200 treatment cat teams registered (注册) by the nonprofit group, Pet Partners. The group helps humans and pets alike by setting them up into teams to provide animal-assisted treatment. The teams visit hospitals, nursing homes and schools and assist those in need.

Chastain Griffin is a researcher who studies the effects of treatment cats. She said that there is a lot of research on other treatment animals like dogs, and many people are surprised to learn that cats can be treatment animals too. However, there is not enough on cats.

Mengel says Lola-Pearl showed signs that she would make a good treatment cat soon after the animal joined her family. Mengel took her new cat to a meeting for the disabled.

Recently people who attended a support group for disabled persons were able to meet Lola-Pearl. They petted her as she woke up from a rest. On the side of the cat carrier she rode in was a sign: “Treatment Cat”.

Mengel was a traveling nurse when she got into a car accident that almost killed her. One of her legs could not be saved. Later, she connected with a friend in Missouri who had a severely injured cat. Her legs were twisted together. An animal medical specialist worked to repair the damage but, in the end, he had to remove one of the baby cat’s legs. Mengel took Lola-Pearl as her cat after talking with her friend. “It’s a really rewarding experience,” she said. “I get just as much out of it as the people that I visit.”

Sharks and their relatives are some of the most threatened vertebrates (脊椎动物) on Earth. Coral reefs (珊瑚礁) provide homes for countless fish species that are vital for fisheries and are therefore an especially important ecosystem for humans — and one where the decline of shark populations seems to be especially sharp.

The study by Simpfendorfer with his team is the result of an act of worldwide cooperation called the Global FinPrint Project. The data analyzed include more than 20,000 hours of standardized underwater video taken at nearly 400 reefs in 67 countries around the world. It reveals declines of 60 to 73% of once-abundant coral reef shark species at reefs around the world. The global conservation status of sharks and rays (鳐鱼) is worse than a decade ago and is even more concerning for some groups of sharks.

However, the findings of Simpfendorfer with his team include signs of hope and a clear path forward. Their result s show that although shark populations in many reefs had declined, some health y reef shark populations remained. The reefs with healthier shark population s had some important similarities: they tended to be in the waters of high-income countries with stronger natural resource management laws and rules. Unfortunately, such countries were relatively rare, and lower-income countries tended to have fewer resources for eco-friendly management.

The most unexpected result of the study is that a decline or complete loss of shark species in one reef was not always associated with similar changes in nearby reefs. They found that one reef could be overfished so badly that a once-common reef shark species was totally gone, but another reef a short distance away could have healthy populations of that same species.

The problem is clear -animals that provide ecosystem services that are vital for human food security and livelihoods are disappearing at an alarming rate. The loss of sharks and the ecosystem services they provide represents an ecological disaster that can cause substantial harm to humans.