3 . The problem with a catchy name is that sometimes it catches on too well. Take the hygiene hypothesis (卫生说) outlined in 1989 by David Strachan of St George’s, a hospital and medical school in London. It suggests that the rise of allergenic (致敏的) sensitivity observed in rich countries over the course of the 20th century may have been caused by a shift from rural to urban living, so that children are no longer routinely exposed to farm animals.

Dr Strachan’s work still has much to recommend it. What the catchy label has encouraged, however, is a false belief that cleanliness is not necessarily a health benefit. In reality, says Thomas Marrs, an allergist at King’s College, London, hygiene is usually about bacteria (细菌) causing infection—and the bacteria that may be beneficial are different from those which do that. But it is plain to see why alternative descriptions, such as “the high turnover and diversity hypothesis” or the “the microbial deprivation hypothesis (微生物剥夺假说)”, have not caught on, more accurate though they may be.

In an attempt to collect further data on the matter, Hisao Okabe of Fukushima Medical University and his team have looked through the Japan Environment and Children’s Study, which tracked over 100,000 births between 2019 and 2022.

Pursuing the animal connection, they looked for correlations between household pet ownership before and immediately after a child’s birth, and any food allergies found in that child’s first three years.

Of the 66,000 or so children they chose to look at, 22% had been born into households with pets. Children in households with dogs, the researchers found, had lower rates than average of allergies to eggs, milk and nuts. Those cohabiting with cats seemed more tolerant of eggs, wheat and beans. However, children whose parents kept turtles (龟) appeared unaffected. And, curiously, those exposed to hamsters (仓鼠) appeared more likely than average to be allergic to nuts.

Confirming or denying this will need more study. Nevertheless, Dr Okabe’s contribution is an interesting addition to the debate about Dr Strachan’s brainchild.

Macquarie Island was a beautiful place where its native    1     (inhabit), including royal penguins, king penguins, and elephant seals, existed in harmony     2    their natural habitat for thousands of years. However, in 1810, humans arrived on the island with rats and mice. These small animals quickly took over the island，    3     (eat) the birds’ eggs and attacking baby birds. Cats were brought to control the rats and mice, but they also enjoyed eating birds. Meanwhile, the     4     (explode) rabbit population provided food for the cats,     5     ( mean) that the number of cats also increased rapidly.

6 . One afternoon in 2022, something on the Internet caught my eye：a tiny hedgehog (刺猬) held by a big hand. The post read: “HELP! My hedgehog abandoned (抛弃) her two babies, and I cannot raise both of them because I have to go to school full­time. Good home with experience needed as soon as possible!”

I had no experience with baby hedgehogs. I was an animal person through and through and had raised cats, dogs, birds, and guinea pigs. But this tiny animal was new to me, and it touched me that he was abandoned, that maybe I could love him and be the best mom for him.

I wrote the most heartfelt email I could. That was how I found my Louie. True to my word, he was my baby. Louie didn’t know he was a hedgehog. He never curled (蜷缩) into a ball, and he liked my two cats, no fear. The cats, however, were afraid of him, as he often moved into the room, running after the cats and blocking my way.

By the time he reached old age, Louie had only three feet. However, he still managed to climb the stairs to visit other animals. He helped me realize my dream of hedgehog photography, a hobby that began during childhood with cats and dollhouses. I love showing off his modeling.

Life has meaning because of the purpose we have. Louie needed a good home and mom, and in return, I got to be a good mother and be needed. Hedgehogs require great amounts of patience, trust, and knowledge—but the payoff (回报) is pretty great.

9 . Grizzly bears, which may grow to about 2.5 m long and weigh over 400 kg, occupy a conflicted corner of the American psyche — we revere (敬畏) them even as they give us frightening dreams. Ask the tourists from around the world that flood into Yellowstone National Park what they most hope to see, and their answer is often the same: a grizzly bear.

“Grizzly bears are re-occupying large areas of their former range,” says bear biologist Chris Servheen. As grizzly bears expand their range into places where they haven’t been seen in a century or more, they’re increasingly being sighted by humans.

The western half of the US was full of grizzlies when Europeans came, with a rough number of 50,000 or more living alongside Native Americans. By the early 1970s, after centuries of cruel and continuous hunting by settlers, 600 to 800 grizzlies remained on a mere 2 percent of their former range in the Northern Rockies. In 1975, grizzlies were listed under the Endangered Species Act.

Today, there are about 2,000 or more grizzly bears in the US. Their recovery has been so successful that the US Fish and Wildlife Service has twice attempted to delist grizzlies, which would loosen legal protections and allow them to be hunted. Both efforts were overturned due to lawsuits from conservation groups. For now, grizzlies remain listed.

Obviously, if precautions (预防) aren’t taken, grizzlies can become troublesome, sometimes killing farm animals or walking through yards in search of food. If people remove food and attractants from their yards and campsites, grizzlies will typically pass by without trouble. Putting electric fencing around chicken houses and other farm animal quarters is also highly effective at getting grizzlies away. “Our hope is to have a clean, attractant-free place where bears can pass through without learning bad habits,” says James Jonkel, longtime biologist who manages bears in and around Missoula.

Shark fin soup,     1     is a famous and expensive dish in southern China, is endangering certain species of sharks and threatening the ocean’s ecosystem.

Sharks are     2     the top of the food chain and they are of great     3     (important)for the ocean’s ecosystem. However, around 70 million sharks     4     (kill)for the fin soup each year and the number of sharks has been falling during the last decades. If their number drops     5     (low)than the current level, life circle in the ocean will be     6     (serious)threatened.

Environmental protection     7     (group)around the world, such as WildAid, are trying to stop the fin soup. They have even asked governments     8     (pass)laws to ban the sale of shark fins. But     9     is not enough. We need to stop     10     (enjoy)the fin soup to save our sharks.