A study published in the journal Nature lists some hybrid (杂种的) species that could become prevalent (盛行的) in the ocean due to climate change. Here are four of those hybrid species.
“Brolar” bears — Brown bears and polar bears
Evidence of a hybrid species born from brown bears and polar bears has been found in the United States and Canada in the past.
Known as “Polar bears” or “Pizzlies”, they have a mostly white coat, with a brownish hue and a nose that is a cross between a polar bear and a brown or grizzly bear.
They are known to be more suited to warmer temperatures than their Arctic relative, as they do not rely so heavily on sea ice for hunting.
“Narlugas” — Narwhals (独角鲸) and beluga whales (白鲸)
In 1990, a hunter in West Greenland discovered an interesting skull, which appeared to be that of a beluga whale-narwhal hybrid. It wasn’t until 2019 that DNA analysis confirmed that the creature was indeed 54% beluga from its father, and 46% narwhal from its mother.
Experts believe that the hybrid may have been grey in color and possessed a tail like a narwhal but forward flippers like those of a beluga whale.
Hybrids of harp seals and hooded seals Numerous species of Arctic seal are expected to mate (交配) to form hybrid offspring due to diminishing sea ice. This includes a hybrid of the harp seal and hooded seal, which both breed on pack ice of the North Atlantic Ocean and extend into the Arctic Ocean in summer months.
A hybrid animal, found in the Gulf of St. Lawrence in Canada, was formally reported and confirmed by molecular analysis in 1997.
“Harbor-Dall” porpoise (鼠海豚) — Harbor porpoises and Dall’s porpoises
Hybrids of the harbor porpoises and the Dall’s porpoises have been found off the coast of British Columbia, Canada. Harbor porpoises are thought to be in decline due to habitat disturbance, meaning they may turn to other species to mate with.
Experts believe more harbor porpoises will move north as temperatures rise, which will further increase their chances of breeding with Dall’s porpoises.
1. What do the four listed animals have in common?| A．They share the same color. | B．They are born due to the polar cold. |
| C．Their parents come from different species. | D．Sea ice is extremely important for them to hunt. |
| A．“Brolar” bears. | B．“Narlugas”. |
| C．Hybrids of harp seals and hooded seals. | D．“Harbor-Dall” porpoise. |
| A．Economy. | B．Education. | C．Entertainment. | D．Environment. |
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【推荐1】How Do Different Animals Sleep?
Big Sleepers
Predators, such as lions and wolves, tend to sleep more than their prey. They also spend more time dreaming, although scientists don’t know why.
Light Sleepers
Giraffes don’t get very much sleep — only a few hours a day. For giraffes, sleeping is awkward and leaves them weak to their enemies. So giraffes mostly take short naps while standing up. But they do need to lie down for half an hour or so of deep, dreaming sleep. It can take a whole minute for a giraffe to get back up on its long legs again.
A Comfortable Bed
Most animals like to find a safe, comfortable place to sleep. Gorillas make themselves sleeping nests of branches and leaves on the ground or in a tree. Every gorilla makes a fresh new nest every night, even if they haven5t moved far from the one they used the night before.
Half-asleep
Dolphins are air-breathing mammals that swim in the sea. But how do they sleep? If they stop swimming to take a nap, won’t they sink and drown? Scientists studying seals and dolphins have discovered a surprising answer — these animals can sleep with one half of their brain while the other half stays awake! While the right half of the dolphin’s brain is asleep, the left half stays awake. This lets the dolphin keep its nose above the water so it can breathe. After about 20 minutes, the sides switch, allowing the other half of the dolphin’s brain to sleep.
Do Bugs Sleep?
Bugs don’t sleep in the same way we do. But they do have periods of rest every day. Dragonflies often have a favorite spot that they return to time after time to rest.
1. What can we know about giraffes’ sleeping habit?| A．They are big sleepers. | B．They don’t need deep sleep at all. |
| C．They usually stand up while sleeping. | D．They tend to sleep more than their prey. |
| A．Wolves. | B．Dolphins. | C．Gorillas. | D．Giraffes. |
| A．They sleep while flying. | B．They sleep on the surface of the water. |
| C．They sleep in the same way humans do. | D．They return to the same place to take a rest. |
【推荐2】Butterflies are the adult stage of an insect belonging to a group called Lepidoptera, which is a Greek word meaning “scaly wings.” The term is appropriate, as the wings of these insects have thousands of overlapping (重叠的) tiny scales. They give the butterfly its super appearance as the scales are set in colorful patterns unique to their species.Butterflies have the typical body of insects: head, thorax, abdomen, and six legs. They also have an exoskeleton (外骨骼) and two feelers.
The first stage of butterfly life is the egg. These shells are tiny and can be roundor oval. Females attach eggs to plant stems or leaves, which serve as food when the larvae (幼虫) hatch.
At the second stage, the larva/caterpillar hatches. The new animal may have a number of legs. Several pairs will be true legs but some will be false legs. The caterpillar has a greedy appetite and spends most of its life eating. It grows a lot during this phase, only the outer skin doesn’t grow along with the rest of its body. Outgrowing its skin, the caterpillar molts, ridding one exoskeleton and replacing it with another. Caterpillars may go through up to five molts.
The third stage is the chrysalis (虫茧). Caterpillars find a spray and make it home. (They may use a wall or other support.) The exoskeleton splits and reveals the chrysalis. The chrysalis shell hangs like a big bag. Inside the shell, the caterpillar breaks down. It rearranges its structure, growing a new body, legs, and wings. Unlike the caterpillar, the chrysalis doesn’t eat. It survives on energy from food eaten during the larval stage. This third step can last from several days to twelve months.
The final stage is the birth of the adult butterfly. The chrysalis splits, and the butterfly emerges.
Most adult butterflies live a week or two. Some species live as long as 18 months.
1. How does the author feel about Lepidoptera?| A．Significant. | B．Typical. | C．Adequate. | D．Specific. |
| A．Changes the old chrysalis into a new one. |
| B．Replaces the original skin with a new one. |
| C．Controls the false legs with the true ones. |
| D．Replaces the old exoskeleton with a new one. |
| A．The first stage of butterfly life. | B．The second stage of butterfly life. |
| C．The third stage of butterfly life. | D．The fourth stage of butterfly life. |
| A．By process. | B．By example. | C．By comparison. | D．By classification. |
【推荐3】Joanne was stuck in a traffic jam in central Birmingham at 5:30, and at 6:30 she was expected to be chairing a meeting of the tennis club. At last, the traffic was moving. She swung quickly racing to her house. As she opened the door, she nearly tripped over Sheba.
“Hey, Sheba,” she said, “I’ve got no time for you now, but I’ll take you out as soon as I get back from tennis club.” Then she noticed Sheba seemed to be coughing or choking. Obviously, she could hardly breathe. Immediately, Joanne realized she would have to take her to the vet (兽医). When she got there, the vet was just about to close for the day. Seeing the state of Sheba, Dr. Sterne brought her quickly into his office.
“Listen, doctor, I’m really in a rush to get to a meeting-can I leave her with you, and go and get changed? I’ll be back in ten minutes to pick her up, and then I’ll take her on to the meeting with me. Is that OK?”
“Sure,” said the doctor.
Joanne made the quick trip back to her house in a couple of minutes. As she was once more entering the hallway, the phone by the door began to ring.
“This is Dr. Sterne,” said an anxious voice. “I want you to get out of that house immediately,” said the doctor’s voice. “I’m coming round fight away, and the police will be there any time now. Wait outside!”
At that moment, a police car screeched to a stop outside the house. Two policemen got out and ran into the house. Joanne was by now completely confused and very frightened. Then the doctor arrived.
“Where’s Sheba? Is she OK?” shouted Joanne.
“She’s free, Joanne. I took out the thing which was choking her, and she’s OK now.”
Just then, the two policemen reappeared from the house, half-carrying a white-faced man, who could hardly walk. There was blood all over him.
“My God,” said Joanne, “how did he get in there? And how did you know he was there?”
“I think he must be a burglar,” said the doctor. “I knew he was there because when I finally removed what was stuck in Sheba’s throat; it turned out to be three human fingers.”
1. What was Joanne supposed to do at 6: 30?| A．To walk her dog. | B．To see her doctor. |
| C．To attend a club meeting. | D．To play tennis with her friends. |
| A．to dress up for the meeting |
| B．to phone the police station |
| C．to catch the badly hurt burglar |
| D．to wait for her dog to be cured |
| A．Sheba fought against the burglar |
| B．the police found the burglar had broken in |
| C．Joanne had planned to take her dog to the meeting |
| D．the doctor performed a difficult operation on the dog |
| A．clever | B．friendly |
| C．frightening | D．devoted |
【推荐1】For generations, young people all over the world have taken an interest in social justice and found the courage to fight for their own rights and the rights of others. Here are four inspiring middle grade books that prove you’re never too young to stand up for what you believe in and make a difference.
This series follows 11-year-old Parvana, who lives under Taliban rule in Afghanistan. When her father is arrested and her family is left without someone who can work or even shop for food, Parvana, forbidden to earn money as a girl, disguises herself as a boy to help her family survive. The Breadwinner is an empowering tale with a sharp and brave heroine.
Stella lives in the separated south in 1932. Out, late one night, wandering around, Stella and her brother witness a Klu Klux Klan activity, starting an unwelcome chain of events in her otherwise sleepy town. With a compelling and courageous voice, Stella tells the story of how she and her community ban together against racism and injustice.
When Julian is sent to stay with his disinterested aunt and uncle for four months, he discovers that his Uncle’s corporation plans to cut down a group of redwood trees at Big Tree Grove and decides to take a stand to save the trees. Perfect for the young environmentalists in your life, Operation Redwood is an adventurous tale as Julian and his friends hatch scheme after scheme to save these giants of nature.
For more mature readers, this unforgettable autobiography tells the true story of Nujood Ali, a ten-year-old Yemeni girl married off at a young age, who decides to resist her abusive husband and get a divorce. A moving tale of tragedy, triumph, and courage, Nujood’s brave resistance has inspired generations of women and young girls.
1. What is the purpose of the four books?| A．To call for people to find the courage. |
| B．To show the definition of social justice. |
| C．To inspire young people to make a difference. |
| D．To prove young people can fight for the rights. |
| A．An adult who shows interest in human nature. |
| B．A college student who majors in human rights. |
| C．A middle school student who is interested in science. |
| D．A high school student who wants to protect the environment. |
| A．I Am Nujood, Age 10 and Divorced. | B．Stella by Starlight. |
| C．The Breadwinner Trilogy. | D．Operation Redwood. |
【推荐2】Social networking websites are an important tool for us to keep up with the world, make new friends, and share pictures, videos, or bits of interesting news. But for people who have very specific interests, a comprehensive site like Twitter is not sufficient. They want to be part of a supportive online community that shares their particular passions. The following are examples of specialized websites for these people.
Stache Passions
It is a social site for people who wear, admire, or have an interest in moustaches. It features photos of men with all sizes and styles of moustaches, forums for discussing the history, growing, and styling of the stache, and even a meet-up page to help you meet other moustache-lovers.
Horyou
It is a website for people who want to do good in the world. On the site, you can connect with other social activists and entrepreneurs (企业家), plan meetings, share fund-raising strategies, and keep up, with thousands of people who are working hard to make the world a better place. There are no funny videos here, but Horyou offers its own web-based video channel that features programs and documentaries about. efforts to improve people's lives around the globe. Watching them will warm your heart and inspire you to work harder for a better world.
Purrsonals
It is a specialized site for those who love cats, Here you can meet and chat with cat-loving friends, set up play-dates with local people and their pets, and even find a temporary home for a cat in need. If your friends don't like it when you share endless cute eat videos on your regular social site, Purrsonals is where people are sure to appreciate them!
1. Which site might be useful for those who are interested in appearance?| A．Twitter. | B．Purrsonals. |
| C．Horyou. | D．Stache Passions. |
| A．Watch funny short films. |
| B．Discuss how to raise money. |
| C．Advertise for social activists. |
| D．Collect ideas for making videos. |
| A．It helps people find their lost pets. |
| B．It collects beautiful photos of cats. |
| C．It offers a great many cat videos. |
| D．It enables people to adopt various pets. |
【推荐3】Eight days for just ¥ 12,000
Departs： May; October 2007
Includes：
•Return flights from 6 China's airports to Naples
•Return airport to hotel transport
• Seven nights' accommodation at the 3-star Hotel Nice
•Breakfast
•The service of guides
•Government taxes
Join us for a wonderful holiday in one of the Europe's most wonderful comers一Naples in Italy if you want to have a nice time in a beautiful small quiet place. The ancient Romans called the city "happy land" with attractive coastline, colorful towns, splendid views and the warm Mediterranean Sea. Your best choice for a truly memorable holiday!
Choose between the peaceful traditional villages of San'Agata, set on a hillside six miles away from Sorrento, or the more lively and well-known international resort town of Sorrento, with wonderful views over the Bay of Naples.
Breathtaking scenery, famous sights and European restaurants everywhere. From the mysterious Isle of Capri to the hunting ruins of Pompeii, and from the unforgettable "Amalfi Drive" to the delightful resorts （度假胜地）of Positano, Sorrento and Ravello, the area is a feast for the eyes! Join us, and you won't be disappointed!
Price based on two tourists sharing a double room at the Hotel Nice. A single room, another ¥2,000. A group of ten college students, ¥ 10,000 for each.
Like to know more? Telephone Newmarket Air Holidays Ltd on : 0845—226—7788 (All calls charged at local rates).
1. All the following are included in the price of ¥ 12,000 EXCEPT _____ .| A．transport between the airport and the hotel |
| B．a double room for every two tourists |
| C．the service of guides to tourists |
| D．telephone calls made by tourists |
| A．¥ 12,000 | B．¥ 14,000 |
| C．¥2,000 | D．¥ 10,000 |
| A．Quiet people. | B．College students. |
| C．Potential tourists. | D．Old people. |
