If humans were truly at home under the light of the moon and stars, we would go in darkness happily, the midnight world as visible to us as it is to the vast number of nocturnal (夜间活动的) species on this planet. Instead, we are diurnal creatures, with eyes adapted to living in the sun's light. This is a basic evolutionary fact, even though most of us don't think of ourselves as diurnal beings. Yet it's the only way to explain what we've done to the night: We've engineered it to receive us by filling it with light.

The benefits of this kind of engineering come with consequences—called light pollution—whose effects scientists are only now beginning to study. Light pollution is largely the result of bad lighting design, which allows artificial light to shine outward and upward into the sky. Ill­designed lighting washes out the darkness of night and completely changes the light levels—and light rhythms—to which many forms of life, including ourselves, have adapted. Wherever human light spills into the natural world, some aspect of life is affected.

In most cities the sky looks as though it has been emptied of stars, leaving behind a vacant haze (霾) that mirrors our fear of the dark. We've grown so used to this orange haze that the original glory of an unlit night—dark enough for the planet Venus to throw shadows on Earth—is wholly beyond our experience, beyond memory almost.

We've lit up the night as if it were an unoccupied country, when nothing could be further from the truth. Among mammals alone, the number of nocturnal species is astonishing. Light is a powerful biological force, and on many species it acts as a magnet (磁铁). The effect is so powerful that scientists speak of songbirds and seabirds being “captured” by searchlights on land or by the light from gas flares on marine oil platforms. Migrating at night, birds tend to collide with brightly lit tall buildings. 

Frogs living near brightly lit highways suffer nocturnal light levels that are as much as a million times brighter than normal, throwing nearly every aspect of their behavior out of joint, including their nighttime breeding choruses. Humans are no less trapped by light pollution than the frogs. Like most other creatures, we do need darkness. Darkness is as essential to our biological welfare, to our internal clockwork, as light itself.

Living in a glare of our own making, we have cut ourselves off from our evolutionary and cultural heritage—the light of the stars and the rhythms of day and night. In a very real sense, light pollution causes us to lose sight of our true place in the universe, to forget the scale of our being which is best measured against the dimensions of a deep night with the Milky Way—the edge of our galaxy—arching overhead. 

1.According to the passage, human beings ________.

A prefer to live in the darkness

B are used to living in the day light

C were curious about the midnight world

D had to stay at home with the light of the moon

解析：选B。B　细节理解题。根据第一段中的第二句we are diurnal creatures, with eyes adapted to living in the sun's light可知，我们人类是白天活动的动物，眼睛适应了生活在太阳的光线中。故答案为B。adapted to和used to同义。

2.What does “it” (Paragraph 1) most probably refer to?

A The night.

B The moon.

C The sky.

D The planet.

解析：选A。A　代词指代题。根据上文中的what we've done to the night可知，我们让夜晚充满光亮，像白天一样。故答案为A。

3.The writer mentions birds and frogs to _______.

A provide examples of animal protection

B show how light pollution affects animals

C compare the living habits of both species

D explain why the number of certain species has declined

解析：选B。B　目的意图题。根据第二段第一句和最后一句，可知无论光洒在什么地方，生活都会受到影响。同时，第三段谈到了光污染，后面的段落是对光污染影响的详细说明，所以作者以鸟和青蛙为例来说明光污染对动物的影响。

4.It is implied in the last paragraph that _______.

A light pollution does harm to the eyesight of animals

B light pollution has destroyed some of the world heritages

C human beings cannot go to the outer space

D human beings should reflect on their position in the universe

解析：选D。D　推理判断题。根据最后一段第二句中的light pollution causes us to lose sight of our true place in the universe可推断出，我们人类应该反思我们所在宇宙中的身份地位。

5.What might be the best title for the passage?

A The Magic Light．

B The Orange Haze．

C The Disappearing Night．

D The Rhythms of Nature．

解析：选C。C　主旨大意题。本文第一段点明文章主旨：人类使夜晚充满了人造光线，使得夜晚不再黑暗，但这么做导致了光污染，其不好影响是非常巨大的。故答案C最合适。主旨大意题应该抓关键词：light, night文中出现频率最高。