EAGLE-EYE

纵使是在光学技术高度发达的今天，人类的眼睛依然具备很多光学仪器无法达到的能力，这就是自然界的力量。但是自然界的力量远不只是人类的力量，今天小编就为大家带来那些自然界中更为犀利的眼神！

The Eagle has eyes quite different from humans, the backs of the eyes being larger and flatter, and thus providing an excellent vision. In the center of the Eagle fovea – focusing point on the retina – there are approximately 1,000,000 cones per mm, compared to the measly 200,000 that humans have, so that objects or prey can be seen much more clearly and sharply, even from great distance.
鹰拥有和人截然不同的眼睛，鹰的眼睛后部更大也更平，鹰也因此获得更好的视觉能力。在鹰眼的中央凹附近，那里拥有每平方毫米1百万个感光单位，而相比人类每平方毫米20万个显得非常少，因此鹰眼即使距离很远也能比人眼看的更清晰，。

CROC-EYE

The beast in the above photo never actually “cries crocodile tears”, because they do not have tear ducts, and cannot weep. The eyes can produce secretions and these  fluids are secreted behind the third eyelid, or nictitating membrane, to both clean and lubricate it as it travels across the surface of my eyes, and inhibiting bacterial growth.
上图所显示的野兽其实从来都不流泪，因为他没有泪腺。它的眼睛可以分泌一些液体，但是必须在他的第三层眼睑以下，这些液体在它的的眼睛里流动不仅可以清洁眼睛还可以抑制细菌滋生。

SNAKE-EYE

Do you know why snakes like the Python shown above always keep the eyes open? They do not have movable eyelids, which help them to lubricate and protect their eyes. This is why snakes always stare at prey. The eyes are protected by tough, immobile, transparent scales.  While snakes do not have very good eyesight, their sense of smell, the reason why their tongues are always so active, is the best in the animal world.  
你知道为什么蛇总是睁着眼睛么？主要是因为它们没有可以活动的眼睑来保护和滋润它们的眼睛。这也是为什么它总是盯着猎物。它们的眼睛被一层坚固的且不可移动的透明薄膜所保护。虽然说蛇的视力并不怎么样，但是他们靠灵活的舌头来产生嗅觉，且嗅觉极其灵敏，这也是为什么他们的舌头总是很活跃的原因。他们的嗅觉举世无双。

FLY-EYE

When it  spots food, it will  fly close to investigate. The head is very large with two large compound eyes, each containing several thousand separate lenses that provide remarkable vision, particularly good for spotting small insects from a long way off.
当苍蝇看到猎物的时候，它们通常会飞近去探查一番。他们的脑袋有两对集群式的眼睛，每个眼睛都包含有成千上万的的独立透镜，这些透镜刻意为它提供绝好的视线即使是特别远的昆虫它也能看到。

CHAMELEON-EYE

The most striking eyes among the reptiles have lower and upper eyelids joined together, leaving one large hole for the pupil to see through. The Chameleon has the ability to roll or rotate each of the eyes independently, to see two different objects from two different directions at the same time. This perfect visual ability gives it a 360 degree field of vision, unique in the natural world.
最令人震惊的是蜥蜴的上下眼睑是连在一起的，这特点让它的眼睛只留下了一个比较大的孔瞳孔接收光线。蜥蜴具有单独旋转两个眼睛的能力，这样它可以同时用两个眼睛看两个不同的方向。这个绝妙的视觉能力使它可以看到360度的方位，这在自然界中绝无仅有。

DRAGONFLY-EYE

Dragonflies are amazing creatures in that each has a pair of large multifaceted compound eyes which occupy almost all of their heads. Each compound eye has up to 30,000 individual lenses, and thus giving these incredible beasts 360 degrees perfect fields of vision.
蜻蜓是一种非常神奇的动物，因为它拥有一对多面体的眼睛，这一对眼睛眼睛集群几乎把它的头部都覆盖了起来。每一个眼睛集群拥有多达3万个独立的透镜，因此这个生物可以看到难以置信的360度的完美视角。

SCALLOP-EYE

Scallops like the one pictured above have many eyes positioned along the right and left valve mantle margins. Each of eye is very unique, functioning like a reflecting telescope to bounce incoming light rays back to theimage-forming retina with an angular resolution of around 2°. The crude image then is formed on light-sensitive cells located in the middle of the eyes. These fantastic shellfish can afford to lose an eye, too, as they are able to regenerate them.
扇贝就如上面描绘的那样，它在自己的身体两侧都分布着眼睛。他的每个眼睛都是独立的，功能就类似于镜面斜率大约有2度的反射望远镜，这可以加强进入眼睛的光线。这些比较粗糙的画面随后就会被位于中间的眼睛的感光细胞所解析清楚。这钟神奇的生物可以丢失一个眼睛也不变瞎，因为它们可以使眼睛再生。