Question

A Colourful Puzzle

People often wear clothing with colours that express something about themselves. A happy person might choose to wear a bright yellow shirt. A swimmer might wear a sea-blue dress.

Animals appear in different colours too, but they don’t get to pick what they wear every morning. Scientists have known for a long time about some of the ways animal colouring can be beneficial. They know that some animals’ colours attract mates or show who is boss. Other animals’ colours blend(融合) in with their environment; thus the animals cannot be seen by their enemies. Still, scientists do not fully understand why blue jays are blue or why rainforest frogs are golden. Now many scientists are working hard to figure out the puzzles of animal colours.

Part of the answer can be found in an animal’s habitat, the place where it lives. It turns out that many animals — especially birds, fish, and reptiles — can see more colours than humans can. These creatures notice colours that stand out in their habitat. For example, forests are mostly green, brown, and yellow. For an animal to be seen by others of its species, it would have to be a different colour than its background. That explains why you can find birds of many shades of blue living in forests.

Another piece of the puzzle lies in what an animal eats. Birds often eat things that have chemicals in them called “carotenoids”(类葫萝卜素). These chemicals are what make tomatoes red and bell peppers bright orange or yellow. When birds eat these foods, the carotenoids affect the colour of their feathers. For example, a cardinal’s bright red feathers will become lighter or darker depending on how many berries it has found to eat.

Some animals do not have any colour at all — but they are not just white; they are transparent(透明的)! Transparent animals live mostly in the ocean. This amazing wonder of nature came about because the animals needed a way to escape their enemies. They are often slow, defenseless creatures that would have no way of fighting back if larger animals wanted to eat them. Because there are few places to hide in the ocean, these creatures have to hide in plain sight. A good example of this kind of transparent creature is the jellyfish. A jellyfish’s body is almost all water, so it is very hard to see it floating in the ocean.

Animals come in all kinds of colours. Their colours are caused by many different factors, and most animals will remain the same colour for their whole lives. Think how lucky we are to get to change our feathers every day!

1.What is the main idea of this article?

A. Animals appear in many different colours.

B. Animals are unable to choose their colours.

C. Animals’ colours are caused by different factors.

D. Animals need colours to blend into their surroundings.

2.According to the passage, what is the reason that some animals are transparent?

A. It marks the places they live in.

B. It shows the leader of the group.

C. It helps them to escape enemies.

D. It allows their mates to see them.

3.It can be inferred that why football players wear uniforms during a game is ______.

A. to identify group members

B. to show their personalities

C. to distinguish the group leader

D. to blend in with the environment

4.The passage is mainly organized by ______.

A. comparisons B. explanations

C. order of events D. order of importance

Answer

1.C

2.C

3.A

4.B

【解析】

这是一篇说明文。文章介绍了导致鸟类呈现不同颜色的几个因素。

1.主旨大意题。第一段以人穿衣不同颜色的衣服引出第二段中“鸟儿的皮毛颜色各异”这个话题。结合第二段中的最后一句和每段的首句可知，该文分析了鸟儿们呈现不同颜色的原因：栖息地，食物，天敌等。最后一段是总结，再次强调“Animals come in all kinds of colours. Their colours are caused by many different factors”，很多因素引起了鸟儿不同的颜色。故C选项正确。

2.细节理解题。根据倒数第二段中的“they are transparent(透明的)! Transparent animals live mostly in the ocean. This amazing wonder of nature came about because the animals needed a way to escape their enemies”可知，有些动物是透明的可以帮助它们逃避敌人。故C选项正确。

3.推理判断题。根据常识可知，某个足球队的运动员穿的服装是统一的，这有助于他们在赛场上识别自己的队友。故A选项正确。

4.推理判断题。结合第一小题的分析可知，文章主要解释了导致鸟儿呈现不同颜色的因素：栖息地，食物，天敌等。并且在相应的段落中进行了具体的解释。故B选项切题。