If you have lived with a cat, you know that these animals can be very active at night and move around the house without bumping into the walls. Considering the ability of cats to avoid collisions at night, the question arises, do cats have natural night vision? Quoted from Karin Plummer, animal ophthalmologist from the University of Florida College of Veterinary Medicine, this question is not quite right. He says:
It is not a matter of seeing or not seeing in the dark. Visual perception depends more on a spectrum than a yes or no answer.
Plummer explains that the amount of ambient light affects a human’s or cat’s ability to see. However, compared to humans, cats are better at recognizing objects in low light, and the reason for this is due to how their eyes have evolved. Plummer says:
Cats can see in the dark due to the structure of their eyes, especially the retina. This feature allows them to see better than humans in low light. Cats also have a high percentage of rod photoreceptors; Therefore, they have better sensitivity to light.
According to the cat welfare charity, the abundance of rod receptors makes a cat’s vision in the dark six to eight times better than that of a human; But why did cats evolve with such exceptional vision? Plummer believes:
Cats’ light adaptation is a direct result of their need to interact with the environment. Cats are inevitable carnivores; It means they have to eat meat to stay healthy. These species cannot produce the proteins they need and must provide them from other sources. Also, many of their prey are active at night or in low light.
Although cats are more active than humans during the night, these species are not only nocturnal animals; Rather, they are known as “twilight” animals or active at dusk. The reason for this feature is their desire to hunt at sunrise or sunset.
Cats are twilight creatures. The reason for this is their desire to hunt at sunrise or sunset.
Although the cat’s eyes were designed for nocturnal wanderings, its ability to find its way in dark environments does not depend only on the composition of the eyes. According to Plummer, cats have other senses. He says:
Cats also have a very strong sense of hearing and smell, which allows them to find their way. Communication with the environment requires the cooperation of all senses.
Therefore, cats are more adept at roaming at night than humans; But when it comes to the quality of vision, they cannot surpass human vision during the day. Ron AfriyProfessor of Animal Ophthalmology says about this issue:
In evolution, every advantage has a cost. Cats have relatively poor daytime vision in exchange for strong night vision; So that their daily vision is approximately one-seventh of human vision. This finding will shock people who always thought that cats have great vision. Yes, cats only have strong vision during the night.
According to Plummer, there are differences between human and cat eyes. For example, cats don’t process color the way humans do. He says:
Compared to humans, the cone photoreceptors of cats have a lower density and number; As a result, they cannot understand the colors and details of its clarity like we do.
The cones of the eye are responsible for determining the color of day vision. Humans have three types of cones that allow them to process blue, green, and red colors; While cats have two types of cones; So, what is green or red to us appears gray to cats. Cats were thought to be color blind for a long time. Meanwhile, many researchers believe that this issue is not true; Although the debate on this issue continues.
Now it is widely believed that cats can see blues and grays and perhaps some shades of yellow and green; But no one can speak accurately about this. Plummer says:
Cats are farsighted; That is, they only have two cone photoreceptors; Therefore, they cannot see as many colors as humans.
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