Eagle

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My eyes have impressed many animals on earth, including you humans. The shape of my eyes is different from yours, the back of my eyes are larger and flatter, and thus providing me an excellent vision.

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Within my retina, there are many cone and concentrated rod cells that dispatch vision information to my brain for further interpretation. In the center of my fovea (focusing point on the retina), there are approximately million cones per millimetres (humans only have 200,000 cones per millimetre), which help me to see an object or prey clearly and sharply.

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Aha, I forgot to tell you that I also have three eyelids, with the bottom eyelid being larger than the top one, and this explains why I always blink up instead of down.

Crocodile

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You English people use a phrase “crying crocodile tears”, which is wrong instead. To make it clear to you, I don’t cry because I don’t have tear ducts. But, well yes, my eyes can produce secretion (products of the lachrymal glands, and this proteinaceous fluid is secreted behind my third eyelid, or nictitating membrane) to both clean and lubricate the passage of the nictitating membrane across the surface of my eyes, while assisting to reduce bacterial growth.

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The edge of my nictitating membrane is visible in the corner of my eyes when I’ve my eyes opened widely. Therefore, you may take me mistaken for crying as you can always see tears forming within my visualized nictitating membrane.

Stingray

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I’ve a bad reputation due to the poisonous sting on my tail. Even though my tail is poisonous, I don’t prefer to sting other animals with my tail. During the day, I prefer to bury my body leisurely beneath the sand. However, in the evening, I’ll pull my body out of the sand to hunt for food. I “fly” almost like a bird in the sea.

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On top of my flat body, there sits my two attractive eyes, so even while resting beneath the sand, I still can see what’s happening around me. But sadly to say, my eyesight can be as poor as an adult old man. Even though my eyesight is extremely poor, I’m still proud of myself as I’m one of a reasonably intelligent animals dwelling in the sea.

Camel

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How would you like me? Am I looking attractive to you? One day, while reading a note left by my ancestor million years ago, I came to realize that we’ve long been awarded by humans as the Ship of the Desert. Hmmm, you know, I can go without water for a month in a desert, because I can drink up to 30 gallons of water at one time. Huh, surprising, right?

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My eyes are large and are located on the sides of my head. Each of my eyes is protected by three eyelids. Two of my eyelids (the lower and upper eyelids) have curly, long eyelashes that help keep swirling dust and sand out of my eyes. The thick bushy eyebrows protect my eyes from the desert sun. I can see through in a sandstorm as I’ve a third thin eyelid.

Snail

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Hey, I’m not blind! I got eyes. Look carefully! My eyes are located on the tip of the tentacles but the sea snail’s eyes are located at the base of the tentacles. Since I’ve two pairs of tentacles on my head, you won’t find my eyes on the shorter tentacles because my eyes are only found on the longer pair.

Panda

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Buddy, don’t you fall in love with my eyes? Interesting though, my BLACK eyes may appear TOO BIG to you, but actually, they aren’t my eyes. They’re black patches around my eyes. My REAL eyes are actually located inside the black patches, can’t you see them? Though I’m grouped under a BEAR category, I’m not similar to most bears as they’ve round pupils. Instead, I’ve pupils that are cat-like vertical slits, and due to this reason, Chinese gave me a name of “xióng māo”, or literally means “large bear cat” or “bear cat”.

Snake

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Do you know why I always keep my eyes opening? The answer is that I don’t have movable eyelids as like most lizards have which help them to periodically close to lubricate and protect their eyes. This is a good reason why I always stare at my prey. My eyes are protected by obvious scales instead.  They’re protected by tough, immobile, transparent scales. Hey, my friend, tell you one secret. Do you know that rattle snake has elliptical pupils? But this is not a case in most non-venomous snakes, as their pupils are not round instead.

You may also see some of my species have a reddish brown ring around the left edge of their pupils. Some of them have green, orange, gold, yellow or brown eyes. You may also fall in love with some of my species that have relatively beautiful grey, gold or blue eyes.

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I use my eyes to detect movement of prey, but I’ve a problem to see a motionless prey or enemies. And I’ve poor eyesight towards objects located at 40 feet, but my vision improves, if the objects are at 10 to 15 feet. Our eyes are not used for detecting foods instead, as like rattle snake, their eyes are adapted for nocturnal searching while for garter snakes, their eyes are adapted for the use of daytime activity.

Gecko

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I’m a small, big head lizard with BIG eyes. At night, while hunting for prey, the vertically slit pupils of my huge globe-like eyes open widely to allow the maximum amount of light to enter, so that I can see clearly at night. However, during the day, my pupils close to a tiny slit. My eyes are protected by a thin transparent membrane, and to keep it clean and moisten I use my long sticky tongue to lick it.

Scallop

You probably don’t know that I’ve eyes. A single of my species may have more than 100 gorgeous blue eyes or “peepers”. Even though we’re the most-eyes marine animals, we can’t see because our eyes are virtually useless in terms of actual vision.

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My eyes are tiny and they’re abundant along the right and left valve mantle margins. Each of my eyes is very unique as they’re functioned like a reflecting telescope that complete with a concave spherical mirror to bounce incoming light rays back to my image-forming retina with an angular resolution of around 2°. The crude image then is formed on light-sensitive cells located in the middle of my eyes. I don’t have to worry if I lose my eye as I can always regenerate it.

Tarsier

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I’m the world’s smallest known primates, but my eyes are enormous in comparison with my body size. Haha…because of my adorable appearance, I’m sure that you’ll fall in love with me. Since my eyes are too LARGE, they cannot be turned around in my eye sockets. However, I’ve a special adaptation in my neck that allows me to rotate at 180 degrees.

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Do you know how large my eyes are? They can be as big as the grapefruit-sized eyes in humans, and not only that, my eyes are the largest among the land mammals. The huge eyes with large pupils provide me very acute night vision to enable me to become an excellent night hunter.

Chameleon

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I’ve the most striking eyes among the reptiles. You’ll observe that my lower and upper eyelids are joined together, leaving one large pinhole for my pupil to see through. I’ve an ability to roll or rotate each of my eyes to see two different objects from two different directions at the same time. This perfect visual ability gives me a 360 degree field of vision.

Chameleon says, “ Don’t trick me! When one of my eyes is looking at you, the other eye of mine is looking back, so please don’t play dirty trick on me.” (quoted from my previous article entitled animal magician)

Frog

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My eyesight is excellent. The protruding eyes on the side of my head help me to see in almost all directions and also to see well in dim light. So, next time, don’t attempt to sneak up me as my bulging eyes can help me to see you in all different angles or directions without my head moving. Under the water, my eyes are protected by a nictitating membrane, which is an extra transparent eyelid.

You can always tell which of us is male or female. If you come across any of my species with their eardrums smaller than their eyes, they’re female frogs. Male frogs have their eardrums as big as their eyes.

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Take a look closely. When I shoot out my tongue, my eyes are always completely shut. This explains that why I can’t see while striking at my targeted meal. My eyes also have a surprising feature that helps me in swallowing my prey. When I’m eating, my eyes sink through openings in the skull to help force the food down to my throat. That’s why you’ll always see my eyes blinking while eating.

Dragonfly

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I’m an amazing animal and have long been known as “snake doctors”. I’ve a pair of large multifaceted compound eyes which occupy almost all of my head. Each of my compound eyes has up to 30,000 individual lenses called ommatidia (a separate light-sensing organ), and thus giving me a 360 degrees perfect field of vision. 

Iguana

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My eyes may make you feeling scary, but do you know that my eyes can detect ultraviolet wavelengths of light that you humans can’t detect. This is particularly useful when I’m basking my body, while allowing me to insure sufficient vitamin production in my skin for a proper mineral absorption. My sensitivity to wavelengths helps me to find my favorable “tidbit” (such as flowers and fruits). Furthermore, my excellent vision helps me exploring safely through the maze of branches in the forest canopy or the crowded forests, and I’m capable enough to detect shapes, shadows, color and movements at astonishingly long distances.

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Don’t disturb me, if you happen to see that I dilate and contract my large pupils in succession, as though an effect of a camera shutter opening and closing, which you human calls “eye flashing”. At this moment, I’m feeling agitated or excited. While resting, my eyelids meet halfway up my eyeballs. Again, don’t disturb my good deep sleep, when you see my lower eyelids moving up to cover my whole eyes.

Moth

Like other adult insects, I’ve compound eyes that are made up of many corneas or hexagonal lens called ommatidia, giving me a broader range of vision, and thus I see an object or prey in the back of my head. Nevertheless, there’s a shortcoming for my compound eyes as I see an image as tiny blurs of light.

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These “peepers” (lenses) help me to focus incoming light onto a rhabdome (or retina in humans). Later, an optic nerve delivers impulse to my brain for further interpretation. Do you know what so special about me? I can see ultraviolet rays that are invisible to you humans.

Our babies can hardly see as they’ve simple eyes called oceilli which only enable them to distinguish dark from light. As their eyes are composed mainly by photoreceptors (light-sensitive cells) and pigments, the image cannot be formed properly. Therefore, our babies can’t see well as the adult moths.

Owl

Of all my external features, my eyes are the most striking one. My eyes are normally large which may take one to five percent of my body weight, but this will depend very much on species. As for your information, my friend, Great Horned Owl, does have eyes as large as a man’s. Since I’ve a wide range of spectacular vision (seeing an object with both eyes), I’m able to see objects in 3 dimensions (height, depth, and width), giving me an ability to judge distances accurately in a similar fashion as humans do.

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In low or dim light, my eyes are large to help gather more light, and thus providing me extraordinary night vision. My eyes are developed pretty well since I was born, and they’re held in place by bony structures in the skull called Sclerotic rings. Due to a reason that I don’t have eye balls and my eyes are fixed in the sockets, I can’t move or roll my eyes. That’s why I always look STRAIGHT ahead! To look on another object, I’ll have to swivel my head, and I can do this movement in an astonishing speed.

There is abundance of rod-shaped, light-sensitive cells in my retina, which are sensitive to movement and light. I possess only few of cone-shaped cells, and thus I can only see in limited monochrome or color.

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You may think that I go blind in bright light. No, no, no, it’s not true, I can see well than you humans. The reason is that my pupils have a wide range of adjustment that allows the right amount of light bouncing onto my retina. Besides that, my eyes are adapted with three eyelids. When I blink my eyes, the upper eyelid is closing; and while I’m asleep, my lower eyelid is closing up. My third eyelid is called nictitating membrane, which is a thin layer of tissue that closes diagonally across the eye, and this eyelid gives protection towards the surface of my eyes.

Jumping Spider

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Don’t humiliate at my small body! Don’t you know that I’m a good jumping champion? In fact, I can leap 10 to 40 times of my body length to avoid becoming prey or to pounce on prey.

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My eyes may appeal to you as alien’s eyes, but I’m actually proud of my excellent vision. Like other spiders, I’ve eight eyes.

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Look closely! I’ve four eyes on my face with the enormous pair located in the center, which makes you seeing me as an alien. My remaining small eyes are located at the dorsal surface of the cephalothorax. Though my field of vision is narrowed to 2-5 degrees, my principle eyes have pretty high resolution, which is at 11 min. visual angle. Since I’ve a sharp vision, I can see my prey anywhere from 30 to 40 cm away. 

Cat

I’m not boasting. My nocturnal vision is by far more superior to you human. My total vision is at 280 degrees, which is wider than you human who only can reach to a total vision of 220 degrees. Yup..yup.., my total vision is even broader than the dogs lol… I can see well than you at twilight. In bright light, my eyes shrink to a mere slit or narrow to a vertical slit, while in dim light, my eyes open widely to allow a maximum of illumination.

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My baby (kitten) goes blind while they were born because they can’t open their eyes until they reach an age of seven to ten. Our visions are significantly weaker than human in the first three months. We can’t see many colors as humans do, because we can only distinguish different shades of greenish and blue yellow. The colors of red and orange appear white to us.

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Watch me! When my pupils dilate, that means I’m angry or I’m sexually aroused; and when I blink my eyes, that means I’m being stroked.

Robber Fly

My grandma told me that our species is one of the 4,000 species fly in the family Asilidae. Human called us assassin fly. But, strange though, human always mistaken us for bumblebee. Wanna pay me a visit? I’ve many “branch offices” in grasslands throughout the world. I’m an impressive predator that loves sun bathing my tender body among the dry open areas which include pastures, sandy places, and etc.

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I’ve an excellent vision that enables me to determine the distance and speed of objects or prey moving in front of me. When I spot something that is food, I’ll fly close to investigate my targeted meal. My head is very large with two large compound eyes, each containing several thousand separate lenses that provide me with a remarkable vision, particularly while spotting a small insect at a considerable distance.

Now, you can read more of my works at my science blog ScienceQuest.