The most unusual eyes of animals (I)

According to scientists, the eyes of animals evolved about 540 million years ago as a simple light detector. Currently, eyesight is the most important sense for many animals, including humans, and they have become extremely diverse and complex. Let's go to Techno World page with some of the most unusual eyes in the animal kingdom.

Tarsier dwarf monkey

Tarsier monkeys are a tiny nighttime primates (roughly the size of squirrels), found in the tropical forests of Southeast Asia. This is a completely carnivorous animal to live only in the world. They eat lizards, insects and even catch flying birds. However, the most notable feature of Tarsier monkeys is the largest, "most" big eyes of mammals, compared to body size.If your eyes have the same proportions as your body, they must reach the size of a grapefruit .

Tarsier's large eyes are fixed in the skull and cannot rotate in the eye socket. To compensate for this, Tarsier monkeys have an extremely flexible neck and can rotate 180 degrees, like owls, to detect potential prey or dangerous predators. With each eye weighing more than the brain, dwarf monkeys have extremely sharp eyesight and excellent night vision. They are even thought to be able to see ultraviolet light. However, Tarsier monkeys seem to distinguish colors very poorly, like many other nocturnal animals, including domestic cats and cat owls.

Chameleon

Chameleon is famous for its ability to change colors - an ability to help them communicate and express their intention or mood before other chameleon (only a few species use changing colors to disguise ).These lizards also possess extremely unusual eyes . Their upper and lower eyelids stick together and cover almost the entire eyeball, except for a small hole for people to see through. Each eye can be moved completely independently of the other eye, so chameleon can both track prey and warn potential threats at the same time. This also means, chameleon has a 360 degree view.

When the chameleon sees a potential prey (usually an insect, although the largest chameleon species is recorded swallowing both mice and other small backbone animals), they focus both eyes in the same direction, achieving stereoscopic vision - this is very important if we consider the chameleon catches prey by releasing its tongue at high speed, a technique that requires approximate evaluation Extremely accurate way and depth.

Chameleon has very sharp eyesight.They could observe an insect a few meters away . And like Tarsier dwarf monkeys, chameleon can see ultraviolet light.

Dragonfly

Dragonflies, an insect that is classified as the most formidable air hunter, are also endowed with "magic eyes" in the animal world. The dragonfly's eyes are so big that they cover almost the entire head, making the insect look like it's wearing a helmet. Like chameleon, dragonflies also have a 360-degree view. Each of their eyes is made up of 30,000 visual units called ommatidia, each containing a lens and a series of light-sensitive cells. The sight of dragonflies is truly amazing. They can detect colors as well as polarized light, and are particularly sensitive to motion, allowing them to quickly detect any potential prey or enemy.

Some species of dragonflies that hunt at dusk can observe well in low light conditions, when we humans can hardly see anything. Not only that, dragonflies also have three smaller eyes called ocelli, capable of detecting movement faster than large double eyes . These ocelli quickly send visual information to dragonfly motor nerve centers, allowing them to respond in a fraction of a second. Although dragonflies are not the only insects that possess ocelli eyes (some species of wasps and flies also have this trait), they possess the most developed secondary eyes.

Leaf gecko

The leaf-tailed gecko possesses eyes that look surreal, with longitudinal humans and a series of "pin holes" that expand at night, allowing them to capture as much light as possible. These eyes also have more light sensitive cells than the human eye, giving the leaf gecko the ability to detect objects as well as seeing colors at night. To make it easier to visualize the great night vision of geckos, you just need to keep in mind that, while cats and sharks can observe 6 times and 10 times better than humans, geckos and geckos Other nocturnal geckos, which possess sharp eyesight, are up to 350 times more powerful than ours in dim light.

Leaf gecko also possesses a variety of strange and complicated eye patterns, helping them disguise. In addition, this animal lacks eyelids. Their eyes are protected by a transparent membrane. It is also often found that geckos clean this protective film with their tongue.

Giant squid

The giant squid ( Colossal Squid ) is the largest invertebrate known to science. They also possess the largest big eyes in the animal kingdom. Each eye of a giant squid can reach a width of up to 30cm and contains a lens the size of an orange . "Cruel" eyes allow ink to be observed in dim light conditions, which are very useful for animals that often spend most of their time hunting at depths of 2,000 meters below sea level.

Until now, humans have only caught and studied immature giant squid. A fully grown giant squid can reach 15 meters long. These big creatures will definitely have bigger eyes. Unlike the large squid (Giant Squid), giant squid has a stereoscopic vision, with a better ability to judge distance. Even more amazing, each eye of a giant squid has a built-in "headlight", which can produce light every time they focus their eyes to look forward to observe the prey in the shadow. dark.

Fish of four eyes

Found in Mexico, Central America and North South America, this is a small fish with a body length of approximately 32 cm and usually lives in freshwater or brackish water (although they are also seen in coastal areas. ). The food of four-eyed fish is mostly insects, so they spend most of their time swimming on the water. Despite the name, the four-eyed fish actually only had two eyes. However, each eye is divided by a strip of tissue and each half of the eye has its own pupil.

This bizarre adaptation allows four-eyed fish to be able to see perfectly simultaneously both above and below the surface of the water, detecting both prey and enemies. The upper half of the eyeball is suitable for looking in the air, while the lower half is adapted to underwater observation. Although both halves of this fish use them as a lens, the thickness and curve of the lens are different in the upper and lower half of the eye, helping them to adjust the different characteristics of the inner light. gas and underwater. This means that, when the four-eyed fish dive into the water, they do not focus on looking with the upper half of their eyes. However, four-eyed fish mostly live on water and only occasionally dive to prevent dehydration of the upper half of the eye.