What is the eyesight of animals? Can all animals see colors? I m sorry to be more detailed, thank yo

Visual acuity, also known as visual resolution, is divided into distance and near vision.

Most herbivores in mammals have average vision, basic color blindness, and no stereoscopic vision.

Most carnivores have good eyesight and stereoscopic vision, but are largely colorblind.

Most primates have good eyesight, stereoscopic vision, and can distinguish colors.

The vast majority of birds have good eyesight, stereoscopic vision, strong color discrimination, and have the function of double adjusting the focal length.

Reptiles, amphibians, and fish have poor eyesight, and most are color blind.

Among the invertebrates, octopuses and squid have better eyesight, close to higher vertebrates.

Others, such as insects, have poor eyesight and can only distinguish objects at close range, but react quickly to moving objects.

Among mammals, primates (monkeys, apes, etc.) and above have color vision, bees can see ultraviolet rays, snakes can see infrared, and others are color blind.

When it comes to the sharpness of the eyes, people always think of the eagle; When it comes to short-sightedness, I can't forget the mouse. In fact, this is just a one-sided view of human beings. If we could really get the animals to say "who has the best eyes", we would hear a unanimous answer:

Your eyes are the best! ”

The eagle eye has a wide field of vision, keen eyesight, and can also find small animals on the ground when soaring at an altitude of two or three thousand meters. If you are at that height, you can see much narrower, but you don't need the eyes of an eagle when you live on land.

Tigers, leopards and other carnivores have eyes on the front side of the head, and the field of view of the two eyes partially overlaps, with good stereoscopic vision, not only can see objects clearly, but also can well distinguish the front and back positions and distances of surrounding objects, such eyes are conducive to the pursuit of prey. The eyes of herbivores such as cattle and sheep grow on both sides of the head, and the field of vision of the two eyes does not match each other, and the overall field of vision is relatively wide, and they are particularly sensitive to moving things, so such eyes are conducive to timely detection of natural enemies who come to sneak attack. For example, a hare's eyes can see things in front of you, left and right at the same time, and you can also monitor your pursuers when you are running forward.

The eyes of aquatic animals are only adapted to seeing things in water; Animals that live in the air and on land do not have good eyes in the water. Amphibious animals such as frogs, turtles, and seals have eyes that can be used both on land and water.

The eyes of daytime active daytime animals, adapted to seeing during the day; The owl on the night shift has excellent night vision eyes. An animal that is active both day and night like a cat, and the size of its pupils can be adjusted freely, and its eyes are easy to use day and night.

Giraffe eyes are adapted to see from a high vantage point, and rat eyes are adapted to see close to the ground in the dark. The chameleon's two eyes can be turned in any direction independently of each other, which is adapted to the need for one eye to stare at the prey ahead and the other eye to guard against the "yellow finch behind". Small insects that fly well in the air need to have a particularly wide field of vision, and their eyes are hemispherical compound eyes.

The mosaic arrangement of thousands of "small eyes" in the compound eye constitutes a wide total field of view, which can be seen in front and back, left and right, and up and down.

The size of the eyes of small animals is particularly large relative to the body, while the eyes of large animals are relatively small. Dolphins and bats can "see" everything around them by relying on their ears when blindfolded, while earthworms do not have eyes and only rely on photoreceptor cells to survive.

Isn't it the mystery of the phenomenon of life in nature that the eye of each animal is the best for itself and is well adapted to survival!

There are still some animals that can be distinguished, and color vision plays different roles in how animals perceive the world and their behavior, ecology, and fundus retina. For humans, color vision plays an important role in the activity of understanding the world, but color vision has little effect on non-human animals, especially those who are not primates. Of course, this does not include hymenopteran insects, which are very dependent on color.

Many animals can see things that we can't see. For example, cats can recognize pearls on a dark night, but we can't. For example, birds can sense ultraviolet light, which can only be seen by people with the help of light filters.

Color Discrimination Master Douli Shrimp, There is a kind of shrimp in the ocean called Douli Shrimp. It has superior eyesight, with 12 different color receptors, while the pigeon's eyes have only 6, the blue rhapsody of the shepherd, humans can see the entire visible spectrum and appreciate the green color on the playground, while the shepherd and the squirrel are both red-green and colorblind, they can only perceive the blue, yellow and gray landscapes.

The latest research shows that dogs can distinguish a number of different colored circles, and slow turtles may look silly, but they have a special structure in their eyes that helps them clearly see things on the dark ocean floor. The photoreceptor in the turtle's eye contains a red oily droplet that blocks waves with shorter wavelengths very well, so turtles can easily see red, yellow, and orange light in the deep sea, but you can't really feel green, blue, violet, etc.

Many people think that horses are colorblind and can only see shades of gray, but this is not entirely true, horses do see colors, but they may not be as vivid as we see. This is because they can only see two of the three visible wavelengths in the spectrum, which is somewhat similar to the way colorblind people observe, horses can't see red, but they can see blue and green, so for horses, the red apples or fresh orange carrots they see may appear brown or green.

Not all animal eyes can not distinguish blue, or there are some animal eyes can distinguish blue, the reason why they can't distinguish blue is mainly because the composition of their eyes is more complex, and some animal eyes do not have the function of identifying blue.

Because the substances composed of animal eyes are relatively special, the substances in their eyes do not have the function of distinguishing blue.

Animals have a different eye nervous system than humans due to their own growth and escape from natural predators, and there are quite few blue animals on the earth, which is also the reason why they can't distinguish blue.

You may be surprised that animals may see colors very different from humans, but what exactly are the colors in their eyes? The Royal Society recently held an exhibition to illustrate the colors in which our pets and other animals look at each other, and the colors we humans look in their eyes. According to the latest research on animal vision, many of them can see ultraviolet light, as well as other colors that we can't see with the naked eye.

Peacocks, for example, they can't see green and blue:

There are four types of cones in the eyes of birds (humans have three) that can see more colors than we do. They can also see ultraviolet light, which makes the peacock's tail's "eyes" (eye-like pattern) look more distinct.

The colors of animals provide some prominent examples of natural selection in the process of evolution. These colors, which are invisible to the naked eye, allow animals to communicate with each other and convey messages, such as attracting the opposite and avoiding predators. It's a language that humans are just beginning to understand.

Dr Tom Pike, Senior Lecturer at the University of Lincoln's School of Life Sciences, said: "We tend to make assumptions about things outside of our conventional vision based on what we perceive in our daily lives, but animal vision, and the resulting perception, is often very different from our own. ”

In many ways, for example, they can see ultraviolet light, they can see polarized light, they can see a lot of colors that we can't see with the naked eye. ”

However, some animals see far fewer colors than we humans – and some are even colorblind. "Since the evolution of animal colors is based on self-interest, not humans, the eye, understood from an animal point of view, can explain that some animals are active and others are dull. Some have a well-developed color perception, while others are poor.

Understanding the importance of colors that we can't see with the naked eye is very important for animal research.

Some can only see black and white, such as cats and dogs, some have many colors, such as birds, and some can see colors that we can't see, and can only be seen through ultraviolet light, such as bees.

Many animals have beautiful eyes, and cats alone have a variety of colors such as green, yellow, orange, and blue, which are very attractive. But as higher creatures, human eyes are mostly black, brown, blue, and amber, and they are far less colorful than animals. Let's hear what the scientists have to say.

Mark Frommer, an ophthalmologist at Mount Lennox Hospital in New York, points out that, in fact, the magical eye color of these animals is not much different from that of human eyes.

When we talk about eye color, we're actually referring to the color of the iris, the color of the ring muscle (sphincter) in the eye. According to Frommer, if the iris contains a lot of melanin, the eyes will appear brown. As the amount of melanin decreases, the eyes appear hazel, green, or blue.

Frommer points out that the animal's eye color also obeys this law.

Orange is actually amber. Gold is a variant of brown. "They're all variations of a very common color. It starts with brown and gradually changes to amber, light brown, green and blue. ”

Cats with bright green eyes are not uncommon.

Of course, there are a few exceptions, and the red-eyed tree frog is one of them. Red does not belong to the color sequence described above. There is a misconception that people with albinism have red eyes.

But in fact, because the part of the gene that controls the formation of melanin in the body of people with albinism is out of function, their iris does not contain any pigment. The red color of their eyes is actually the color of the blood vessels that supply blood to the iris.

As for rumors that the famous actress Elizabeth Taylor (1932-2011) had purple eyes, Frommer said that he had never heard of or seen anyone with purple eyes. But according to his speculation, if someone had light blue eyes and red blood vessels, blue and red would have mixed into purple.

He added that when a person's pupils dilate or contract, the color of the eyes may also change. When the pupil dilates (i.e., the pupil grows to let in more light), the iris is in a state of contraction, and the color of the eye may darken due to the increased density of melanin.

Conversely, when the pupil is constricted, the iris dilates and the eye becomes lighter.