题目内容

When people first walked across the Bering Land Bridge thousands of years ago, dogs were by their sides, according to a study published in the journal Science.

Robert Wayne of the University of California, Los Angeles, and Jennifer Leonard of the Smithsonian Institute, used DNA material—some of it unearthed by miners in Alaska—to conclude that today’s domestic dog originated in Asia and accompanied the first humans to the New World about 10,000 to 15,000 years ago. Wayne suggests that man’s best friend may have enabled the tough journey from Asia into North America. “Dogs may have been the reason people made it across the land bridge,” said Wayne. “They can pull things, carry things, defend you from fierce animals, and they’re useful to eat.”

Researchers have agreed that today’s dog is the result of the domestication(驯化) of wolves thousands of years ago. Before this recent study, a common thought about the precise origin of North America’s domestic dog was that Natives domesticated local wolves, the descendents(后代) of which now live with people in Alaska, Canada, and the Lower 48.

Dog remains from a Fairbanks-area gold mine helped the scientists reach their conclusion. Leonard, an evolutionary biologist, collected DNA from 11 bones of ancient dogs that were locked in permafrost(永冻层) until Fairbanks miners uncovered them in the 1920s. The miners donated the preserved bones to the American Museum of Natural History in New York City, where they remained untouched for more than 70 years. After borrowing the bones from the museum, Leonard and her colleagues used radiocarbon techniques to find the age of the Alaska dogs. They found the dogs all lived between the years of 1450 and 1675 A.D., before Vitus Bering and Aleksey Chirikov who were the first known Europeans to view Alaska in 1741. The bones of dogs that wandered the Fairbanks area centuries ago should therefore be the remains of “pure native American dogs,” Leonard said. The DNA of the Fairbanks dogs would also expose whether they were the descendents of wolves from North America.

Along with the Fairbanks samples, the researchers collected DNA from bones of 37 dog specimens(标本) from Mexico, Peru, and Bolivia that existed before the arrival of Columbus. In the case of both the Alaska dogs and the dogs from Latin America, the researchers found that they shared the most genetic material with gray wolves of Europe and Asia. This supports the idea of domestic dogs entering the New World with the first human explorers who wandered east over the land bridge.

Leonard and Wayne’s study suggests that dogs joined the first humans that made the adventure across the Bering Land Bridge to slowly populate the Americas. Wayne thinks the dogs that made the trip must have provided some excellent service to their human companions or they would not have been brought along. “Dogs must have been useful because they were expensive to keep,” Wayne said. “They didn’t feed on mice; they fed on meat, which was a very guarded resource.”

1. The underlined word “remains” is closed in meaning to ______.

A. leftover food B. dead bodies

C. animal waste. D. living environmet

2.According to the study described in Paragraph 4, we can learn that ______.

A. the bones studied were not from dogs brought into North America by Europeans

B. the 11 bones of ancient dogs are not from native American dogs

C. the bones discovered by the gold miners were from North American wolves

D. ancient dogs entered North America between 1450 and 1675 AD

3.What can we know from the passage?

A. Native Americans domesticated local wolves into dogs.

B. Ancient dogs entered North America across the Bering Land Bridge.

C. Latin America’s dogs are different from North America’s in genes.

D. Scientists discovered some ancient dog remains in 1920s.

4.The first humans into the New World brought dogs along with them because ______.

A. dogs fed on mice

B. dogs were easy to keep

C. dogs helped protect their resources

D. dogs could provide excellent service

5.The passage mainly talks about ______.

A. the origin of the North American dogs

B. the DNA study of ancient dogs in America

C. the reasons why early people entered America

D. the difference between Asian and American dogs

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阅读下面短文,从短文后各题所给的四个选项(A、B、C和D)中,选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。

Whenever my child caused me to change my schedule, I thought to myself, “We don’t have time for this.” _________ , the two words I most commonly spoke to my child were: “Hurry up” But my promise to _________was made almost three years ago, and I began my journey to grasp what _________in life. My younger daughter is my living _________of why I must keep trying. In fact, the other day, she reminded me once again.

The two of us had taken a bike ride to the _________ . After buying a cool treat for my daughter, she sat down at a table in _________ admiring the ice cream she held in her hand. Suddenly a look of worry _________ on her face. “Do I have to rush, Mama?”

I could have _________ .Perhaps the pains of a _________ life don’t ever completely disappear, I thought sadly. As my child looked up at me waiting to know _________ she could take her time, I knew I had a(n) _________ . I could sit there _________ about the number of times when I rushed my child through life….or I could celebrate the fact that today I’m trying to do things _________ . I chose to live in today.

“You don’t have to rush. Just take your time,” I said in a(n) _________ way. Her whole face instantly brightened and her shoulders _________ . And so we sat side by side talking about things that interested us.

When she got to the last bite, she held out a spoonful of ice crystals and sweet juice for me. “I _________ the last bite for you, Mama,” my daughter said _________ . As I left the icy goodness put out my thirst, I _________ I just got the deal of a lifetime. I gave my child a little time… and_________ , she gave me her last bite and reminded me that things taste sweeter and love is _________ to get when you stop rushing through life.

1.A. However B. Instead C. Therefore D. Besides

2.A. speed up B. slow down C. give up D. keep on

3.A. works B. happens C. minds D. matters

4.A. reminder B. message C. example D. guide

5.A. church B. park C. supermarket D. school

6.A. relief B. sorrow. C. advance D. delight

7.A. brought in B. turned up C. went by D. made up

8.A. cried B. hated C. wondered D. regretted

9.A. difficult B. desperate C. hurried D. terrified

10.A. when B. if C. how D. what

11.A. duty B. chance C. choice D. idea

12.A. thinking B. complaining C. worrying D. talking

13.A. differently B. vividly C. perfectly D. casually

14.A. angry B. obvious C. gentle D. cautious

15.A. raised B. relaxed C. shook D. trembled

16.A. saved B. tasted C. purchased D. rushed

17.A. frequently B. carefully C. proudly D. slowly

18.A. realized B. imagined C. expected D. remembered

19.A. in contrast B. in return C. in charge D. in control

20.A. harder B. better C. closer D. easier

Nowadays the U.S. students are sleepy in school because they spend too much time texting, playing video games, watching TV and using the media in other ways.

“Heavy media use interferes with sleep by reducing sleep duration, making it harder to fall asleep, and lowering sleep quality,” Meilan Zhang, an assistant professor at the University of Texas at El Paso, wrote in her research review in the journal, Sleep Medicine.

But the relationship between youth’s media use and sleep is not so simple, said Michael Gradisar, who authored both that review and the Sleep Medicine meta-analysis. “Technology use is the new evidence when we are trying to answer ‘Why are school-age children sleeping less?’” said Mr. Gradisar, an associate professor of psychology at Flinders University in Adelaide, Australia.

There may be safe limits to technology use, Mr. Gradisar stated. For instance, recent research results indicate that using a bright screen for an hour before bed or even playing violent video games for less than that will not necessarily interfere with teenagers’ sleep, he wrote.

But longer periods of usage can be harmful to sleep, Mr. Gradisar added. Rather than delaying school start times, he said, the first step should be educating parents about limiting the hours that their children are using technology before bed, and enforcing a consistent bedtime.

Early school start times are also commonly blamed for students’ sleepiness, especially for adolescents. Secondary schools around the nation and the world have been delaying start times, often with positive results.

Mr. Minnich of the TIMSS and PIRLS International Study Center hesitated to put blame to any particular factor. But he did think that cost-saving measures to consolidate(合并)bus routes might help explain U.S. students’ sleepiness.

“For those children who board the bus first, they must get up earlier, may end up sleeping on the way to school, and may end up arriving at school sleepy.” he said.

1.Which of the following may be the good way to help kids sleep better?

A. Parents should be well educated.

B. Technology is forbidden at home.

C. Their playing time must be limited.

D. They are allowed to go to school early.

2.What would be the factors that cause kids sleep troubles according to the text

a. Using the media.

b. Having breakfast.

c. Catching the bus.

d. The school timetable.

e. Doing too much homework.

A. a, d, e B. b, c, d

C. a, c, d D. b, d, e

3.Which of the following may be the best title for the text?

A. Kids benefit a lot from technology.

B. Several sleep troubles appear at school.

C. Some tips can help kids sleep well.

D. Several factors affect kids’ sleep.

Put a group of strangers in a room together, and they’ll probably start a conversation. “Hot today, isn’t it?” one might say. “You said it,” another replies.

Why do we talk so much about the weather? When we meet new people, we don’t begin by telling them our life story. We start with small talk, a polite conversation about something like traffic or weather.

Research suggests that small talk can build new friendships. When we begin conversations with new people, we want to feel comfortable, and so do they. We use small talk to find common interests. Once we have a common interest, a friendship can begin.

Small talk even helps people get a job. In order to impress at a job interview, you need to bond with the interviewer right away. Proper small talk can make that first impression get you the job.

So, how can you make small talk lead to a new friendship or job? First off, find common ground. Select something around you that you share with the other person.

Next, keep the conversation going. Compliment (赞美) the other person to make him or her feel comfortable, and ask questions to show interest.

Third, keep eye contact. When you loop people in the eye, they feel you appreciate what they are saying. It makes you appear honest and build trust.

Naturally, shy people might not have enough confidence to start up conversations with strangers. Talking to someone you don’t know is not the easiest thing to do! Some experts say with more practice, small take does get easier.

Some people avoid small talk because they dislike discussing things like traffic or weather. For them, they are just too small. However, when you think about it, small talk is anything but small. In fact, it is actually a very big deal!

Title

Small Talk: A Big (76) _________

Introduction

We are likely to make small talk when we (77) _______ meet people.

(78)___________

Small talk can help people form (79) ________ friendships.

Small talk can also help people get (80) __________.

Advice

Find some topics (81) ________ with the other person.

Keep the talk going by making compliments and (82) __________ questions.

Keep eye contact in conversation to build (83) ________.

(84) _________ more in order to make small talk easier.

Conclusion

Small talk really (85) _________ a lot to us.

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