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Our companions have a visual perception of their surroundings and environment that is significantly different from ours. Many false (and real) ideas circulate on this subject. From the anatomical and histological study (structure at the cellular scale) of the eye, veterinarians were able to determine how cats perceive shapes, movements, light or colors. Focus.
The cat sees in black and white: true or false?
False. The retina is composed essentially of two types of visual cells: for simplicity, let us remember that the cones allow the vision of the colors, and the rods allow a vision by low luminous intensity. The study of retinal cat cells shows that it has fewer cones than humans, but many more sticks. Thus, the small number of cones and their arrangement on the retina induces the researchers to think that the cat would not distinguish red, but on the other hand it would differentiate blue from green and yellow. The palette of colors perceived by the eye of the cat is therefore actually less wide than that of the man, but it has in no case a vision in black and white.
The cat sees better at night than man: true or false?
True. As seen in the previous paragraph, the cat has considerably more sticks than the man. The rods being the cells of the retina that allow vision by low luminous intensity, it makes sense to think that the cat has better night vision than us. The observation of the nocturnal behavior of the cat confirms us every day: it is considered that the threshold at which the cat can no longer see in the dark is six times lower than in man. This is why the cat is a rather nocturnal animal. However, due to the large variability in the size of his pupil, he is able to adapt to large variations in luminosity.
The cat has better visual acuity than the man: true or false?
False. The ability of the cat to distinguish forms in general is quite mediocre, especially closely. On the other hand, the cat perceives very well, far and better than any object in motion (it is a hunter!).
The cat sees behind him: true or false?
Rather false. It is the arrangement of the eyes on the head that determines the width of the visual field. The more the eyes are placed laterally on the skull, the larger the field of view, the better the animal sees behind it. However, in mammals, as a rule, herbivores (prey) have their eyes placed most laterally, which allows them to see the carnivores (predators) arrive even if they are placed behind them. On the other hand, the carnivores often have the eyes closer, which favors the binocular vision, that is to say the vision in relief and in perspective: this favors the hunting. This is the case of the cat, whose visual field is smaller than that of the horse for example, but also that of the dog which is less carnivorous than him. On the other hand, it should be noted that the cat has a wider field of vision than the human, whose two eyes are a little closer on the face. The man distinguishes better the reliefs than the cat.
Let us remember that the cat sees less well behind him than the horse (or the gazelle ...), but better than the man who sees only in front of him. On the other hand, he sees better the perspectives than the horse, but less well than the man.
The visual capabilities of the cat are therefore different from ours, although the overall structure of the eye is very close. A better understanding of how our companions perceive colors, shapes or movements also allows us to better understand their lifestyles and behaviors.
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