Question

Fish have ears. Really. They’re quite small and have no opening to the outside world carrying sound through the body. For the past seven years, Simon Thorrold, a university professor, has been examining fish ears, small round ear bones called otoliths.

As fish grow, so do their otoliths. Each day, their otoliths gain a ring of calcium carbonate (碳酸钙). By looking through a microscope (显微镜) and counting these rings, Thorrold can determine the exact age of a young fish. As a fish gets older, its otoliths no longer get daily rings. Instead, they get yearly rings, which can also be counted, giving information about the fish’s age, just like the growth rings of a tree.

Ring counting is nothing new to fish scientists. But Thorold has turned to a new direction. They’re examining the chemical elements (元素) of each otolith ring.

The daily ring gives us the time, but chemistry tells us about the environment in which the fish swam on any given day. These elements tell us about the chemistry of the water that the fish was in. It also says something about water temperature, which determines how much of these elements will gather within each otolith ring.

Thorrold can tell, for example, if a fish spent time in the open ocean before entering the less salty water of coastal areas. He can basically tell where fish are spending their time at any given stage of history.

In the case of the Atlantic croaker, a popular saltwater food fish, Thorrold and his assistant have successfully followed the traveling of young fish from mid-ocean to the coast, a journey of many hundreds of miles.

This is important to managers in the fish industry, who know nearly nothing about the whereabouts of the young fish for most food fish in the ocean. Eager to learn about his technology, fish scientists are now lending Thorrold their ears.

1.What can we learn about fish ears from the text?

A. They are small soft rings.

B. They are not seen from the outside.

C. They are openings only on food fish.

D. They are not used to receive sound.

2.Why does the writer compare the fish to trees?

A. Trees gain a growth ring each day.

B. Trees also have otoliths.

C. Their growth rings are very small.

D. They both have growth rings.

3.Why is it important to study the chemistry of otolith rings?

A. The elements of the otoliths can tell the history of the sea.

B. Chemical contents of otoliths can tell how fast fish can swim.

C. We can know more about fish and their living environment.

D. Scientists can know exactly how old a fish is.

4.How would you understand “fish scientists are now lending their ears”?

A. They are very interested in Thorrold’s research findings.

B. They want to know where they can find fish.

C. They lend their fish for chemical studies.

D. They wonder if Thorrold can find growth rings from their ears.

Answer

1.B

2.D

3.C

4.A

【解析】

试题分析：鱼儿也有耳朵。它们的耳朵不仅非常小，而且是不外露的。鱼儿通过身体来感知声音，它们的听觉器官叫做otoliths，otoliths会随着鱼的生长而发生变化。人们可以通过观察鱼的otoliths来判断鱼的年龄。

1.They’re quite small and have no opening to the outside world carrying sound through the body”可知，鱼有耳朵，但鱼的耳朵不是外露的，而是通过身体来听声音，故选B。

2.Instead, they get yearly rings, which can also be counted, giving information about the fish’s age, just like the growth rings of a tree.”可知，当幼鱼长大一些的时候，它们的otoliths开始每年增加一环，据此可以判断鱼的年龄，就像通过树的年轮判断树龄一样，故选D。

3.but chemistry tells us about the environment in which the fish swam ...These elements tell us about the chemistry of the water that the fish was in. It also says something about water temperature”可知，通过研究otoliths的化学成分，可以了解鱼的生活环境、水质和水温等情况，故选C。

4.Eager to learn about his technology”可知，就Thorrold的研究成果而言，鱼类科学家们愿闻其详，他们很渴望了解Thorrold的研究技术，故选A。

考点：科学类短文阅读