-
(单词翻译:双击或拖选)
Human vision like that of other primates2 has evolved in an arboreal3 environment. In the dense4 complex world of a tropical forest, it is more important to see well that to develop an acute sense of smell. In the course of evolution members of the primate1 line have acquired large eyes while the snout has shrunk to give the eye an unimpeded view. Of mammals only humans and some primates enjoy color vision. The red flag is black to the bull. Horses live in a monochrome world .light visible to human eyes however occupies only a very narrow band in the whole electromagnetic spectrum5. Ultraviolet rays are invisible to humans though ants and honeybees are sensitive to them. Humans though ants and honeybees are sensitive to them. Humans have no direct perception of infrared6 rays unlike the rattlesnake which has receptors tuned7 into wavelengths8 longer than 0.7 micron. The world would look eerily9 different if human eyes were sensitive to infrared radiation. Then instead of the darkness of night, we would be able to move easily in a strange shadowless world where objects glowed with varying degrees of intensity10. But human eyes excel in other ways. They are in fact remarkably11 discerning in color gradation. The color sensitivity of normal human vision is rarely surpassed even by sophisticated technical devices.
点击收听单词发音
1 primate | |
n.灵长类(目)动物,首席主教;adj.首要的 | |
参考例句: |
|
|
2 primates | |
primate的复数 | |
参考例句: |
|
|
3 arboreal | |
adj.树栖的;树的 | |
参考例句: |
|
|
4 dense | |
a.密集的,稠密的,浓密的;密度大的 | |
参考例句: |
|
|
5 spectrum | |
n.谱,光谱,频谱;范围,幅度,系列 | |
参考例句: |
|
|
6 infrared | |
adj./n.红外线(的) | |
参考例句: |
|
|
7 tuned | |
adj.调谐的,已调谐的v.调音( tune的过去式和过去分词 );调整;(给收音机、电视等)调谐;使协调 | |
参考例句: |
|
|
8 wavelengths | |
n.波长( wavelength的名词复数 );具有相同的/不同的思路;合拍;不合拍 | |
参考例句: |
|
|
9 eerily | |
adv.引起神秘感或害怕地 | |
参考例句: |
|
|
10 intensity | |
n.强烈,剧烈;强度;烈度 | |
参考例句: |
|
|
11 remarkably | |
ad.不同寻常地,相当地 | |
参考例句: |
|
|