Question

    Sea otters (海獭) are pretty small compared to other marine mammals (哺乳动物).which means that, despite their fur coats, they tend to lose het quickly, and need lots of energy to keep up their body temperature.

"So they need to eat 25 percent of their body weight each day," says Sarah McKay Strobel, a sensory ecologist at UC Santa Cruz. "But in order to eat that much food, that means sea otters need to find all that food. " She studied the otter's senses, to solve the mystery of how they're such efficient food catchers. Vision isn't reliable, she says- it's pretty dark and muddy underwater, and crabs and other smaller animals tend to hide. Hearing is also tough for otters, in the noisy underwater environment. And sniffing's no good either. "When they're underwater they're holding their breath."

What's left is touch. So Strobel measured the sensitivity of the otters' paws and whiskers (须). She blindfolded an otter named Selka, then presented it with plastic plates carved with tiny grooves (沟槽). Selka's job was to select the plate with two-millimerter grooves, which she'd been trained to associate with tasty food, instead of plates with differently sized grooves.

Tums out, Selka could tell just a quarter millimeter difference in the grooves' with with her paws - above and below water - and hall a millimeter difference with her whiskers. "The fact that she was able to perform so well while moving extremely quickly I think is really interesting and suggests that sea otters have very quick decision-making abilities and very quick sensory processing abilities, which makes sense when you think about the type of lifestyle they lead and how quickly they need to find food."

For the record, humans can feel the difference too, but it takes us 30 times longer, which might make sense. After all, we live in environments where touch is less important in a hunt than sight and sound.

1.Why do sea otters eat much food?

A.To swim faster. B.To stay warm.

C.To keep their fur thick. D.To satisfy their good appetite.

2.What does paragraph 3 mainly talk about?

A.An introduction to Selka. B.The use of plastic plates.

C.An experiment on Selka. D.The function of otters' touch.

3.What did Strobel find about sea otters' senses?

A.Hearing is useless. B.Touch is the most elective.

C.They have no vision. D.Their smell works very well.

4.What can we learn from the text?

A.Sea otters have enough food to eat.

B.Humans are more sensitive than sea otters.

C.Sea otters respond very quickly in hunting.

D.Sea otters' whiskers work better than paws.

Answer

1.B

2.C

3.B

4.C

【解析】

这是一篇说明文。文章介绍海獭的生活习性。

1.推理判断题。根据第一段中they tend to lose het quickly, and need lots of energy to keep up their body temperature.“它们往往很快就会失去热量，需要大量的能量来维持体温。”由此可知，海獭吃很多食物是为了保持温暖。故选B。

2.段落大意题。根据第三段中She blindfolded an otter named Selka, then presented it with plastic plates carved with tiny grooves (沟槽). Selka's job was to select the plate with two-millimerter grooves, which she'd been trained to associate with tasty food, instead of plates with differently sized grooves.“她蒙住一只名叫塞尔卡的水獭的眼睛，然后给它看刻着细小沟槽的塑料盘子。塞尔卡的工作是选择带有两米里默特凹槽的盘子，她被训练将其与美味食物联系起来，而不是选择带有不同大小凹槽的盘子。”由此可知，第三段讲述的是“Selka的一个实验。”故选C。

3.细节理解题。根据第三段第一、二句What's left is touch. So Strobel measured the sensitivity of the otters' paws and whiskers (须).“剩下的是触觉。因此，Strobel测量了水獭爪子和胡须的敏感度。”由此可知，Strobel发现了海獭的触觉是最具选择性的。故选B。

4.推理判断题。根据第四段中The fact that she was able to perform so well while moving extremely quickly I think is really interesting and suggests that sea otters have very quick decision-making abilities and very quick sensory processing abilities,“她在移动速度非常快的情况下表现得如此出色，我认为这一点非常有趣，这表明海獭具有非常快的决策能力和感官处理能力，”由此可知，海獭在捕猎时反应很快。故选C。