All along, we often see eyes with different colors, patterns and abilities in various film and television works.
Superman's eyes, for example, can emit a hot, dangerous-looking gaze that burns enemies.
Thermal sight
In the anime Naruto, the "Writing Wheel Eye" of the Uchiha clan can directly learn the enemy's tricks by looking at each other.
Write the eye of the wheel
In some wonderful and strange works, we can also see that the prophetic wizard has the ability to see through the future...
sorcerer
All of this reflects the reverie of human beings for visual ability, and interestingly, when the reverie shines into reality, it becomes the appearance of an aquatic animal.
Shoot water fish
Fish have special visions that we humans do not have, helping them to complete hunting and underwater survival, and fish in different waters have developed unexpected visual abilities.
Shooting fish, living in the sea or rivers on the Pacific coast, silver and adult water shooting fish are about 20 cm long, only need gray-black skin, accompanied by two black stripes, our water shooting fish is "assembled" complete. The shooting fish is known for its wide range of attacks and high accuracy, just like the snipers in the animal kingdom.
sniper
Human snipers need excellent vision, and sniping is the housekeeping skill of shooting water fish, and its eyes are also worth mentioning.
It is well known that the refractive index of light in air and water is not the same, the former is 1, the latter is 1.333 terrestrial animal cornea refractive index of 1.376, in short, when humans look into the water, the fish is actually not where we see. The refractive index of the fish cornea is similar to that of water, so when the fish look at humans in the water, the people the fish see are in what position, and they are not biased. Moreover, the aquatic body of the fish eye is spherical, and the distance between the crystal and the retina becomes smaller, which strengthens the degree of farsightedness and is very suitable for viewing various objects in the water.
Shoot water fish hunting
If you just look far away, see accurately, then the ability of the water-shooting fish may not be worth mentioning, humans also have good vision, the really powerful visual ability of the water-shooting fish is reflected in its brain, the water-shooting fish brain has a wealth of reticular cells, each reticular cell is connected with tens of thousands of secondary sensory neurons. This means that once the prey is observed by the eyes of the water shooter, the brain of the water shooter can immediately transmit the prey information in real time through a large number of reticular cells to the motor and nervous system, dynamically analyzing the prey until the prey is captured, or escapes, although this is basically impossible.
Unlike the shooting fish, which bathes in the sun on the surface of the water all year round, the deep water fish has been living silently in the claustrophobic darkness. For example, the night mode of the mobile phone can make the night as day with an exposure ranging from 1-60s, and if the water depth is 100 meters, the SLR camera with a larger sensor needs to be exposed for more than two hours to barely see the surrounding scenery. If the water depth reaches more than 1700 meters, even if the camera is exposed for 2 hours, the negative film is as black as ink.
The deep sea full of unknowns
No matter how hot the sun is, it is dim at 1500 meters of water.
In order to adapt to this dark environment, deep-sea fish evolved huge eyes. Half of the lantern fish's head is used to hold the eyes. Their pupils are also unusually shaped, becoming thin and long, which helps to improve their ability to absorb light. Of particular interest are the eyes of the triad marlin larvae. Their eyes grow on two long fleshy handles, thus broadening their horizons. The silver-axe also grows special light emitters that deliberately stimulate their retina to maintain sensitivity to light so that they can see farther away on the dark seabed.
Silver axefish
And the eyes of the squid with different sails are one big and one small, which is unique in the world. When swimming in deep water, it is usually necessary to extend the wrist downwards, with one large eye opening vertically upwards and the small eyes looking downward. Scientists speculate that his large upward eyes can find prey by catching the shadows of fish skimming overhead, while the small eyes below are used to emit flashes of light to avoid revealing shadows to unknowable creatures below, and it is actually the eyes that deceive the eyes!. And because the energy required by the big eye is even greater, the squid in the evolution of the sail squid only got one big eye. With two eyes, one large and one small, mastering both prey and hunter at the same time, we may be able to glimpse the difficulty of life in the deep sea from its visual ability.
Small eyes
Big eyes
The eyes of the deep-sea squid can be gorgeously juggled up and down, and the amphibious fish are not to be outdone. A four-eyed fish that lives in the Americas has a horizontal diaphragm in the eye, which divides an eye into upper and lower parts, and the lens of the upper half is flatter than the lower half. Ability to see things on both the water and land at the same time. They often swim close to the surface of the water, observing aerial targets with the upper part of their eyes and underwater targets in the lower part.
Four-eyed fish
Horseshoe crabs also have 4 eyes and 2 single eyes in front of the brain, each about 0.5 mm in diameter. Don't look at their eyes are small, but they have a body, a retina, and there are 50 to 80 photoreceptor cells on the retina. The single eye is dedicated to the feeling of ultraviolet light. On each side of their heads there is also a strange large eye, each consisting of about 1000 small eyes, which is the compound eye of the horseshoe crab. Scientists have found that every small eye in the eyes of the horseshoe crab is connected to the nerves, and when one eye feels the light, it will quickly transmit signals to the surrounding eyes, and the surrounding eyes are immediately suppressed. After a series of processing of this signal inside the computer, the horseshoe crab can draw an image, and even if it is underwater with five fingers out of sight, it can still understand the surrounding situation.
horseshoe crab
The military intelligence agency has a kind of horseshoe-eye electronic simulator that can process blurry satellite photos to achieve a clear outline of the target. This electronic simulator is made according to the structural principle of the crab eye.
Horseshoe crab 2d analysis plot
The aquatic animals introduced above show their own supernatural abilities and show their more powerful adaptability under the cruel screening of the environment. Unlike the flounder, although it is also a "superior student" of survival competition, it is more like a "poor student" who is beaten in the competition, and the final score is just above the passing line, and its visual ability has no elegance at all. And on the contrary, if the long weird is also an ability, then the flounder can hit the first.
Juvenile flounder
In fact, when the flounder is young, it is also like other fish, and the two eyes grow asymmetrically on both sides of the head. At that time, they were very active and often floated on the surface of the water to play. Only when they grow up, because the various parts of the body are unbalanced, they slowly turn their bodies sideways when swimming, so they have to lie on their sides on the seabed. At the same time, the eye on the lower side of their side will shift upwards because of the rapid growth of the soft belt under their eyes, through the back, and lean side by side with the upper eye, like a happy fat house that is out of shape because of gluttony and laziness.
Adult flounder
As a result, their eyebones are naturally generated, and then they no longer move but are fixed, and the two eyes are ugly and crowded on the top of the head. However, flounder did not abandon themselves. Because I live on the seabed for a long time, I often lie on my side in the mud and sand, and the two eyes that are squeezed on my head just happen to observe the situation above, perfectly interpreting "where you fall, you lie down."
Animals are the product of the environment, and when they really face darkness, hunger, and threats, these aquatic animals use their unique visual abilities to see their own light.