Ⅲ.阅读理解
A
People diet to look more attractive. Fish diet to avoid being beaten up, thrown out of their social group, and getting eaten as a result. That is the fascinating conclusion of the latest research into fish behavior by a team of Australian scientists.
The research team have discovered that subordinate fish voluntarily diet to avoid challenging their larger competitors. “In studying gobies we noticed that only the largest two individuals, a male and female, had breeding (繁殖) rights within the group，” explains Marian Wong. “All other group members are nonbreeding females, each being 510% smaller than its next largest competitor. We wanted to find out how they maintain this precise size separation.”
The reason for the size difference was easy to see. Once a subordinate fish grows to within 510% of the size of its larger competitor, it causes a fight which usually ends in the smaller goby being driven away from the group. More often than not, the evicted fish is then eaten up.
It appeared that the smaller fish were keeping themselves small in order to avoid challenging the boss fish. Whether they did so voluntarily, by restraining how much they ate, was not clear. The research team decided to do an experiment. They tried to fatten up some of the subordinate gobies to see what happened. To their surprise, the gobies simply refused the extra food they were offered, clearly preferring to remain small and avoid fights, over having a feast.
The discovery challenges the traditional scientific view of how boss individuals keep their position in a group. Previously it was thought that large individuals simply used their weight and size to threaten their subordinates and take more of the food for themselves, so keeping their competitors small.
While the habits of gobies may seem a little mysterious, Dr. Wong explains that understanding the relationships between boss and subordinate animals is important to understanding how hierarchical (等级的) societies remain stable.
The research has proved the fact that voluntary dieting is a habit far from exclusive to humans. “As yet, we lack a complete understanding of how widespread the voluntary reduction of food intake is in nature，” the researchers comment. “Data on human dieting suggest that, while humans generally diet to improve health or increase attractiveness, rarely does it improve longterm health and males regularly prefer females that are fatter than the females' own ideal.”
文章大意：大千世界，无奇不有。人节食是为了苗条，有魅力。鱼节食又是为何?作者从鱼类与人在节食问题上的对比，揭示出了一个令人深思的话题——人类的节食真是发自内心的吗?其本质目的何在?
1.When a goby grows to within 510% of the size of its larger competitor, it ________.
A.faces danger
B.has breeding rights
C.eats its competitor
D.leaves the group itself
答案：A 细节判断题。文章第三段指出：当稍小一些的鱼一旦长到它竞争者体积的5～10%时，将引发战争。结果大多是小一点的刺鳍鱼被逐出群体，最终被吞食掉。
2.The underlined words “the evicted fish” in Paragraph 3 refer to ________.
A.the fish beaten up
B.the fish found out
C.the fish fattened up
D.the fish driven away
答案：D 词义猜测题。紧承前一句...which usually ends in the smaller goby being driven away from the group可知the evicted fish指的是被逐出群体的挑战失败者。
3.The experiment showed that the smaller fish ________.
A.fought over a feast
B.went on diet willingly
C.preferred some extra food
D.challenged the boss fish
答案：B 推理判断题。文章第四段结尾the gobies simply refused the extra food they were offered, clearly preferring to remain small and avoid fights, over having a feast说明刺鳍鱼的节食是自愿的。而第六段更指出小一点儿的刺鳍鱼节食对于维护鱼类社会稳定的重要性。
4.What is the text mainly about?
A.Fish dieting and human dieting.
B.Dieting and health.
C.Human dieting.
D.Fish dieting.
答案：D 主旨归纳题。文章主要论述了刺鳍鱼节食的问题。指出这一行为是它自愿的，一种目的在于维护它们的整体稳定的行为。
