Humans may be a bad influence on their best friends---at least when it comes to problem-

Humans may be a bad influence on their best friends---at least when it comes to problem-solving. In a task that wasn’t very tough, wolves performed must better than dogs. All the animals had to do was pull the lid off a food container, containing a sausage treat.

Monique Udell studies animal behavior at Oregon State University in Corvallis. She tested 10 pet dogs and another 10 dogs from an animal shelter. In one set of tests, a person was nearby but did not encourage or discourage the dogs. Those dogs typically spent 10 to 15 percent of their time gazing at the person. They spent a mere 5 percent of their time or less touching the container.

Udell offered the same challenge to wolves. These animals had been raised and fed by people but still lived outdoors. Here, the wolves didn’t look at the nearby person. Instead, they devoted about 90 percent of the time to struggling with the box holding a treat.

When someone walked around the dogs and actively encouraged them to keep trying to open the  box, the dogs did spend more time handling the problem. A few more even managed to open the box. But their success rate still did not match the wolves. The dogs and wolves were also tested when no one was present. But even then, the dogs didn’t paw or teat the box much more than they did when a human was present.

29. According to paragraph 2, how did the dogs perform in the experiment?

A. They showed reduced intelligence

B. They found the treat in the box less attractive

C. They found the wolves were dangerous

D. They spent more time waiting for help

30. What was the effect of encouragement on the dogs?

A.It made their success rate improve a lot

B.It made them seek less guidance

C.It made them a little more devoted to the task

D.It made them able to compete with the wolves

31.What is the main idea of the text?

A. How wolves and dogs differ from each other

B. The reason why wolves are dangerous

C. Dogs are more relaxed when no one is around

D. Wolves beat dogs in problem-solving tests

答案

DCD

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