题目内容

Scientists think they have answered a mystery: How some ocean creatures got so huge so quickly.

A few million years ago, the largest whales, averaged about 15 feet long. Then seemingly overnight, one type of whale, the toothless baleen whale(须鲸类)became huge. Modern blue whales get as big as 100 feet. Nicholas Pyenson of the Smithsonian Natural History Museum said, “Why is that?” ”It happened in the glance of an evolutionary eye, which makes it harder to figure out what happened,” said Graham Slater, lead author of the study. Their study has suggested an answer: Ice ages in the last 3 to 5 million years started it, changing the oceans and food supply for whales.

The researchers used fossil records of the smaller whales to create a family tree for baleen whales which include blue whales, humpbacks and right whales. Using computer simulations(模拟)and knowledge about how evolution works, they concluded that when the size changes started, the poles got colder, ice expanded and the water circulation in the oceans changed and winds shifted, Slater and Pyenson said cold water went deep and moved closer to the equator(赤道)and then eventually moved back up with small fish and other small animals that whales eat.

Baleen whale, which have no teeth, feed by eating huge amounts of fish they capture. Toothed whales, like sperm whales (抹香鲸), hunt individual fish, so the ocean chants that made food less evenly spread out didn’t affect them as much. But baleen whales hunt schools of fish.

Olivier Lambert at the Royal Belgian Institute of Natural Sciences calls it “a really convincing situation”. But he said the lack of fossils in certain time periods is an issue. As oceans warm from man-made climate change, the seas will be more like it was when the whales smaller and they will have a more difficult time surviving.

1.What does the author mean by “It happened in the glance of an evolutionary eye” in the second paragraph?

A. The change of baleen whales happened too quickly.

B. The change of baleen whales was too difficult to explore.

C. Researchers paid little attention to the change of baleen whales.

D. Researchers thought the change of baleen whales was unimportant.

2.What played the key role in baleen whales’ becoming huge?

A. Man-made climate change.

B. Its eating a huge amount of fish.

C. The water circulation in the oceans.

D. The increase of food supply for whales.

3.What do we know about sperm whales and blue whales according to the text?

A. Sperm whales eat more food.

B. Blue whaler live much longer.

C. Sperm whales prefer to hunt schools of fish.

D. Blue whales usually swallow schools of fish.

4.What can we infer from the last paragraph?

A. There are no whale fossils now.

B. The whales may become even bigger.

C. Global warming has threatened the whales.

D. Olivier Lamber thinks the study is perfect.

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Phillida Eves and her husband Tedd Hamilton weren't unhappy living in the Galway countryside with their sons, Cian and Oisín, and their daughter, Soracha. "We had a lovely home, a car, lots of friends, and weekends sailing our boat," says Phillida. "But there's a line from a poem that goes: 'Tell me, what is it you plan to do with your one wild and precious life?' That says it all for me. We felt there was more to life."

So they quit their jobs, took their sons, then aged six and nine, out of school and went to southern Spain where they bought a 15-metre yacht(游艇) and headed up the coast to Barcelona. Soracha was not even three. And they brought along Poppy, the family dog. Now, two and a half years and 10,000 km later, they don't intend to stop. Tedd is a yacht engineer and can find work in ports. But, says Phillida, a supply teacher (代课老师), "Any family could do this."

The children are home-schooled using a correspondence course (函授课程). "My son had a recent project on the weather. The weather is crucial to us. My son knows more than most adults about weather systems, compasses, maps and directions. The weather, for him, means life or death."

Other subjects have become equally vivid. "They're living geography and history all the time. We've sailed round Italy, Sardinia, Sicily, and seen tiny islands we didn't know. The kids learned about ancient Romans by visiting Rome."

But what about social development? Again, Phillida is sanguine. "The children have become much more socially confident since we set out. They play with tons of families of all nationalities on other boats we meet."

Living for the moment, they believe, is a huge life lesson. "Our children never say they're bored." The other day they stopped mid-ocean and the kids swam, 110 km from land. "That's the kind of freedom we want for them," says Phillida. "That's the kind of freedom they've got."

1.The couple quit their jobs and took their children traveling because  .

A. their children wanted to make friends of all nationalities

B. they wanted to experience more in their lives

C. their children wanted complete freedom

D. they were unhappy with their lives

2.The underlined word "sanguine" in Paragraph 5 is closest in meaning to "  ".

A. patient B. curious

C. excited D. optimistic

3.The author describes the children's home schooling by  .

A. using examples

B. making comparisons

C. following the order of importance

D. describing the changes in space order

1.The big firms are competing ___________ (fierce) on price.

2.The books__________(write) by Mo Yan are popular with us.

3.It is also the most exciting city in New Zealand with people of many different cultures________(live) there.

4.Here ________(come) the bus.

5.I don’t want to add _____ your trouble.

6.The matter ________(relate) to people’s health surely requires dealing with carefully.

7.Sales director is a position ______ communication ability is just as important as sales skills.

8.She is talented _____ singing.

9.It’s hot today. Do you feel like ________ (go) for a while?

10.We all agree that the last one __________(come) will pay the bill.

11.It is reported that many a new house __________(build)at present in the disaster area.

12.The ___________(command) decided to make an air strike on the enemy's supply line.

13.I feel greatly honored __________________ (invite) to the party.

14.Finally he reached a lonely island ______ was completely cut off from the outside world.

15.You may rely on ______that the work will be finished ahead of time.

16.The children went home from the grammar school, their lessons __________ (finish) for the day.

17.Plays were often in competition with each other, and ______________ (prolong) clapping helped a play to win.

18.This was the first time my parents________(learn) about my disappointing behavior at school.

19.When the lava reached the sea, there was the possibility ____ a huge tidal wave.

20.There is every _________ (indicate) that the operation has been a success.

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