Eyes have been around for a long time, over 550 million years ago. The first windows to the soul may have been just pitted with special tissues that can detect light. Evolution over time created corneas and lenses that could adjust light rays for better viewing. Such animal eyes became especially important for living on land. For fish, the cornea became a unique structure for forming images.
Read: These Albino Animals Are The Snow-Whites Of The Animal Kingdom
On the other hand, some creatures still have basic structures like mollusks and flatworms. Others developed mirrored components and elaborate dynamic pupils. Even animal eyes that are not their primary sense, incredible features can be found. Gaze into these select animal eyes that will leave you in wonder. Some are similar to ours while some are certain to make you jealous.
Mossy New Caledonian Gecko
Image credits: Chris Mattison/Alamy
This species of gecko is also the biggest species of gecko that have been discovered by humans. Full-grown adults can reach are known to reach a maximum length of 14 inches. Similar to its relatives who are nocturnal like this gecko, it slaps its eye with its tongue. This wipes the grime away from the eye.
Bigfin Reef Squid
Image credits: Andrey Nekrasov/Alamy
Are you wondering about the silver glow emanating from the animal eye of this squid? The possible cause of it is two structures. One is cells filled with small plates for reflecting light. The other is legions of minuscule pigmented organs. Cephalopods can choose to relax or contract this organ.
Atlantic Nurse Shark
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This shark species feeds by sucking. As such, these animal eyes are closed during the daytime. The marine animals also stay completely still while it snoozes. Thus, it is the only species of sharks that have shown several attributes of “sleep” among animals.
Coral-boring Scallop
Image credits: David Fleetham/Alamy
There are 11 animal eyes in this picture. The mollusk’s eyes, however, are not used for focusing light using lenses, unlike most other animals’ eyes. Rather, there are reflective crystals (found in chameleon skin and carp scales) that direct rays by gathering them.
Gray Whale
Image credits: Christopher Swann/Science Source
A member of the cetacean family of aquatic animals, these animal eyes function similarly. Whales are known for breaking the surface to take a breath of air. As a result, its eyes have to cope with the intensity of light changing when they break the surface after diving into the ocean. These animal eyes do the coping by contracting their pupils. The shape changes to a crescent in the shape of a bean from the usual circular shape. The pupil rests at its eyes’ bottom part. Then it becomes a crescent faintly visible that connects two small holes.
Parrot
Image credits: Anna Om/Getty Images
Human eyes cannot detect light that lies in the range of ultraviolet frequency. That is beyond the boundary of our eyes. However, the eyes of birds can detect and see light rays at these wavelengths. Parrots make great use of these wavelengths for finding mates as well as in their habits for finding food.
Four-eyed Fish
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This picture of the species shows only one of the eyes. If you notice, there are two lobes in that eye. One of them is located over the line of water while the other one is situated inside the water. This is the reason behind its moniker “four-eyed”. The fish cruises along the surface of the water as it snacks on floating critters and items.
Wood Louse Spider
Image credits: Mihai Andritoiu/Alamy
Spiders usually have eight eyes. These unique species are one of the relatively few spider species that does not have eight, but rather six. In other words, these spiders do not have the usual “principal eyes”. For most other spider species, these principal eyes are used for conveying color vision as well as increasing spatial acuity.
Indian Elephant
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One of the animal eyes that you may find some resemblance with. However, research on the eyes of elephants has revealed some more similar features. During the daytime, elephants probably cannot properly see the colors red and green, similar to some humans. This means that fail to differentiate between the colors properly.
Read: Elephant Herd Takes Over Internet As They Fall to Sleep After Trekking
Horsefly
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These flies are not the usual flies that you usually find in your house. These insects have a peculiar attraction towards the light that is polarized. This means that light rays whose direction of vibration is directed in the same way attract the horseflies. Females of this species make use of the polarized beams to locate prey. They track the polarized beams that are reflected off of the hair of the fly.
Tokay Gecko
Image credits: Sebastian Janicki/Alamy
Similar to some other geckos and reptilians, the pupil has a slit down the middle. This pupil can be constricted. Upon constriction, the edges that are scalloped merge together. This gives rise to create four pinholes that are shaped like diamonds. These also give rise to a total of four images of the object being viewed on the retina of the gecko. However, the convergence of the images depends on the distance of the object. The reptile possible uses the amount of convergence to figure out how far it is from an object.
Crocodile Fish
Image credits: Bruce Shafer/Science Source
This unique fish species can be found lurking around sandy floors of oceans. The covering of these animal eyes that looks like it is made out of lace is known as the iris lappet. This covering droops over these animal eyes to obscure the pupil. It aids in improving the overall camouflage of the fish.
Feature image credits: Jeff Rotman/Alamy