Nationalgeographic.co.id-When you see the world in a certain way, it’s easy to forget that not everyone has the same vision.
Humans really take everything literally. In addition to philosophical considerations about the subjective experience of color, different organisms have evolved to perceive the world differently, with structures and configurations eye optimized for different types of existence.
Something’s clear, of course: herbivores’ horizontal pupils give them a panoramic view of their surroundings, which helps both to spot predators coming, and to avoid obstacles when animal escape. Meanwhile, nocturnal predators have vertical pupils to maximize their night vision.
There is no animal others that have squid -like pupils. Its shape is like the letter W, a property that has been determined by biologists helps animal balance the uneven vertical light fields, which are common in the depths of the water they inhabit. But that’s just the beginning.
Cuttlefish have only one type of photoreceptor, meaning they can only see in monochrome. But the oddly wide pupils of cuttlefish and other squid can facilitate an entirely different way of seeing color – by using the way light passing through a prism splits into a rainbow.
Known as chromatic aberration, this can be a problem when the lens is eye we ourselves fail to focus colors on the same point, turning sharp color contrasts into softer washes of color. Cuttlefish may have turned this problem into a solution.
The smaller the pupil, the smaller the effect, so the wide pupil of the cephalopod is particularly susceptible to it. While this might result in a blurry image, the blurring is color dependent–which means it could be a way for these apparently colorblind creatures to see color. Maybe they can see colors we don’t even know about! It could also explain how they can color coordinate themselves with their surroundings for camouflage.
Unlike other cephalopods, eye cuttlefish can rotate, allowing them to see the world in 3D as well; Recently, scientists discovered eye This rotation produces stereoscopic vision, giving another advantage to the squid in their environment.
A Himalayan blue tail that migrates
Birds, with eye small as beads, may be able to see a lot that we can’t.
Cephalopods have only one type of photoreceptor, as previously discussed. Humans have four, three cones and rods, which means we have color sensitivity at three peak wavelengths, which we call trichromatic vision.
Birds have six–four cones that provide unusual tetrachromatic vision, rods, and double cones for colorless perception of motion.
In addition, the protein in eye they allow them to see magnetic fields. Migratory birds can navigate very well, and for a long time, it was not clear how they got there. Recently, scientists have narrowed it down to a class of proteins called cryptochromes, which are sensitive to blue light.
Birds’ magnetoreception—that is, their ability to sense magnetic fields—appears to be dependent on blue light, suggesting that senses may be sight-based. There is a distinct possibility that this magnetic filter for blue is the result of quantum peculiarities. New laboratory studies have shown how magnetic fields affect the quantum properties of cryptochromes, regulating their electrons.
The strange eyes of the four-eyed fish
Take a look eye four large scale (Anableps anableps), of the genus four-eyed fish.
animal this dazzling one actually doesn’t have four eye—but his two eyes have evolved into an extraordinary adaptation. Their ecological niche is the surface of the water, where they spend most of their time, preying on insects that hover around the aquatic ecosystem.
Eye they are located above their heads, it is better to see flying insects in the air environment. But part of their optic organs are below the water’s surface, and this is where things get interesting: each pupil is divided into two halves, one of which is above the water’s surface (dorsal), while the other is below (ventral), pointing outward. down to the murky depths.
In this way, fish can simultaneously see above and below water–an environment where light propagates differently–to keep an eye on predators and prey. The thickness of the lens also varies, to accommodate the different refractive indices of air and water media, as does the thickness of the corneal epithelium.
And the proteins in retinal photoreceptor cells are also slightly different—more sensitive to green light in the dorsal retina, and more sensitive to yellow light in the ventral retina. Since fish often live in muddy environments, such as mangroves, this is thought to improve vision in murky waters.
Peacock grasshopper shrimp
Of all the eyes in the animal kingdom, the most complex ones we know of include bottom-dwelling marine crustaceans that spend their lives in burrows in rocks and on the ocean floor.
Humans have four photoreceptors, of course. Birds have six–amazing. The mantis shrimp of the order Stomatopods, small accomplished wotsit, have their 16 compound peeps. What do they do with these photoreceptors? They see. They see all things. Don’t play hide and seek with mantis shrimp.
In fact, we don’t know why mantis shrimp need such complex visual organs, in large part because it is so difficult for us to conceptualize what they see. They have ordinary color photoreceptors, as well as photoreceptors that are sensitive to ultraviolet light. It’s not unique; some insects, birds, and even reindeer can see ultraviolet light. mantis shrimp? They can see five different ultraviolet frequency bands.
In addition, mantis shrimp can see polarized light; that is, the orientation of the oscillating light wave propagating. Many animals can see linearly polarized light, including cuttlefish. The mantis shrimp is the only animal that can see circularly polarized light that we know of.
Each eye is mounted on a stalk, and can be moved independently. And every eye has the ability to sense depth. Humans rely on binocular vision for depth perception. Mantis shrimp only need one. They can even spot cancer before symptoms appear.
If it’s not an ocular superpower, we don’t know what it is.
West Indian fuzzy chiton
What are the eyes made of? The answer is tissue, usually–a structure made of cells. Unless the organism is a type of marine mollusk called Chiton, from the class Polyplacophora.
These diminutive creatures lived their lives protected by thick plates of interlocking armor as they crept across the rocks, grazing whatever they found there. You might think such a creature would have soft eyes that could peer around the edges of its shell to watch for predators and sense the day-night cycle.
You are wrong. chitons have eyes, of course–but they are embedded in their armor, and made of minerals; more specifically, a type of calcium carbonate known as aragonite.
The simple chiton eye, which grows on the surface of its shell along with hundreds of sensory organs known as aesthetics, consists of an aragonite lens covered by a cornea, and a kind of retina; To the surprise of scientists, this tiny primitive organ can literally amaze everyone.
What we don’t know is how that visual information is processed by the brain–chitons don’t do much in that department.
But they can help us better understand some of the wild paths evolution has taken in the past. Trilobites, for example, also had mineral eyes, with lenses made of calcite.
These extinct creatures had the first truly complex eyes that we know of, so understanding them can tell us a lot about how vision evolved on Earth in all its fascinating complexity.