On numerous occasions we wonder how dogs see, others, on the other hand, we already take for granted that dogs see in black and white, because that is what has been said for many years.
But, although it has been believed for many years, it is not easy to ensure that this information is completely true, especially since it is not possible to ask them and have them tell us how they see, what shades or if they really see with blurred edges. Or not.
However, numerous studies have been carried out in this area and by comparing them; some very significant results have been achieved on the vision of dogs.
Do you want to know what the results were? Do you want to know how dogs see? Well, keep reading this article, because we are going to solve all your doubts.
Vision function
Before saying how dogs see, it is important to understand the visual function and what are the factors to take into account to give rise to vision. These factors are:
- Visual field. The entire area that our eyes are capable of capturing and that we can see in the same image.
- Depth perception (This is the ability to measure and distinguish distances)
- Acuity (It is the ability to focus the gaze on something).
- The perception of movement
- Color difference
All these factors or aspects will be collected by the eye and processed by the brain, thus forming the vision or image that we see about something.
In black and white or in color
While it is generally thought that dogs see in black and white, these studies have shown that dogs can have a degree of color vision. How do you know? Well, because for the perception of color to occur, there must be some cones, that is, some photoreceptors of the retina that is the ones that are stimulated in environments of intense lighting. In the case of dogs, these cones represent about 20% of the photoreceptor neurons of the central retina, while in humans the cones represent 100%.
Some behavioral and retinal stimulation tests have also been carried out, stimulating it at different wavelengths. Thanks to these studies it has been possible to verify that dogs can distinguish the colors yellow and blue, and often confuse green and red. However, red and green do not see them as we do, for them green is a gray-yellow and red is a yellow-brown. It is what is known as dichromatic vision, that is, they perceive two colors, whereas humans have trichromatic vision, that is, we see with three color receptors, red, blue, and yellow.
Other Aspects of Dog Vision
Peripheral vision. Peripheral vision will be determined by the position that the eyes occupy in the head and by the amount of visual field that is capable of seeing with both eyes at the same time, (which professionally is called binocular vision and that is precise to be able to measure distances correctly). Regarding humans, the binocular field of vision of dogs is more or less half; instead their visual field covers 240 degrees, while that of humans only reaches 200 degrees.
Dogs have undergone some adaptive genetic modifications throughout their history, and we can also find some of these modifications in the eyes. The eyes have adapted to the needs of nocturnal hunters. Under the retina they have a special structure called the tappet lucid, and what it does is that in cases of dim light or dim light, this structure works as if it were a mirror, forming a reflective layer that intensifies vision. This structure is what produces the sparkle in a dog’s eyes when they look at a car with its headlights on or are shot by a camera flash.
Regarding visual acuity, (which is the ability to focus so that two objects look like different entities), people can measure it with a visual panel, but in the case of children or animals it is necessary to measure it using a retinoscope. Studies show that a dog’s visual acuity is also less than that of a human. What we can see up to 25 meters away, the dog will distinguish it up to 6 meters away. For what is this?
Well, visual acuity depends on the structure of the eye, especially the shape and position of the cornea and lens. In the case of dogs, the determining optical structure is the cornea, and on the other hand, the lens does not accommodate as much as that of humans, and in general it is less important than it is for humans. For example, in the case of a cataract extraction operation, in humans it is necessary to insert an intraocular lens, so that vision is not reduced, in the place of the lens, while in dogs it is not essential to replace the lens by this artificial lens, although it may be desirable, so that vision is sharper and blurring in vision can be reduced.
In this aspect, it is worth noting the great capacity that dogs have to function in familiar spaces using the rest of their senses in case of having a serious visual deficit.
In summary:
Dogs distinguish colors! In addition to black and white, they also see blue and yellow, and also red and green, although they confuse red with green. Their field of vision is much larger than ours and their twilight vision is also much better (night vision). In addition, they also capture movement much better than we humans do.
Blind dogs
Are there blind dogs? Yes, as in humans there are also numerous diseases that affect canine vision, some diseases can be treatable with medication, others operable, but others are irreversible. While it is true those dogs adapt better when they gradually lose their vision and not all of a sudden, blind dogs have a great capacity to adapt, and to continue performing their main functions. They will also use their other senses, smell and hearing, which are much more developed than ours, so the loss of vision will not be so frustrating, because they do not depend on it as much as we do. If you have a pet that is going blind or is already blind, it is important to take into account some details. Think of your dog as if he were a blind human, although he has it much easier due to the great development of his other senses, the truth is that they also need a routine and a fixed arrangement of objects, to avoid accidents and disorient them. Although the loss of vision does not affect them so much, remember to give them love, affection and cover their needs. You must also show him that nothing is wrong, that everything is as before and nothing has changed, because if you tend to overprotect him and pamper him excessively, your dog can spoil himself and become unbearable. Dogs are very smart, and if they see everything that worries you about their situation and how they treat it, they will end up believing they are the leader of the house and will not obey your orders, so do not be afraid to remain firm with the rules at home.
Canine entertainment
After these studies, a company has created the first exclusive television channel for dogs, it is a channel where programming is broadcast to relax and entertain our pets, but the images have also been treated so that dogs seem as alive as possible.
You see that black and white vision is a myth, now we know how dogs really see, and although they do not enjoy such a wide range of colors as we do, nor do they see colors as vividly, the truth is that at least they see in color and enjoy the contrasts they perceive with color differentiations. After everything we have told you about how dogs see, do you think it makes a big difference for them to see in black and white or in color? Is it really important to see everything in color to appreciate its beauty? Undoubtedly for humans sight and seeing in color are very important, but for all beings that can appreciate something in color is it like that?
