Mary Allen
Cats perceive the world very differently than humans. Read here what colors cats see, why cats get along so well in the twilight and what special features the cat’s eye has.
The fascination of cat eyes lies more in our “cat image” than in the actual sensory organ of the cat, which is basically similar in structure to the human eye.
Roughly speaking, the eye of every mammal consists of a hole (pupil) through which light falls on the lens. Light rays are refracted by the lens and, after passing through a dark chamber (the vitreous body), fall on a light-sensitive layer (the retina). There it comes to the depiction of what is seen.
Cats Can See These Colors
A cat’s world is probably a little grayer than ours. The receptors in the cat’s eye are made up of fewer cones, which are cells that allow us to see color. Cats also lack those cones that are sensitive to red light. For example, the cat can probably distinguish between green and blue, but perceives red only as shades of grey.
In return, the cat has more “rods” that are responsible for light sensitivity and light-dark perception. In addition, the cat is a master of the “quick eye”. Special receptors in her eyes serve as motion detectors and enable her to react at lightning speed. In addition, cats perceive movements in more detail. They can process more frames per second than humans.
A study by the Zoological Institute in Mainz showed that blue was the favorite color of many cats. In order to get to the food, the cats had to choose between yellow and blue. 95% chose blue!
Cat Eyes Are Huge Compared to the Human Eye
With a diameter of 21 mm, the cat’s eye is huge – in comparison, the eyes of the much larger human reach a diameter of just 24 mm.
In addition, the cat’s eye appears rigid. We humans are used to seeing a lot of white in the eyes of our fellow human beings. When people change the direction of their gaze, the iris appears to move across the white field of the eye. In the cat, the white is hidden in the eye socket. If the cat changes the direction of its gaze, we hardly see “white” and believe that the eyes are still.
The pupils, which can narrow into vertical slits, are unnerving to some people because they are reminiscent of reptilian eyes. In fact, the cat with these vertical pupils can dose the incidence of light much more finely than we humans with our circular pupils and can thus make maximum use of the incident light.
That’s Why Cats See So Well at Dusk
Cat eyes are known for their reflective ability. Cats get by with five to six times less light than humans, which of course is very helpful when hunting at dusk. One of the reasons for this “clairvoyance” in cats is the “tapetum lucidum”, a reflective layer on the cat’s retina. This layer of the cat’s eye serves as a “residual light amplifier” by reflecting every ray of light and thus activating the cat’s visual cells again.
Its large lens also contributes to better utilization of the light. After all, cats have around twice as many light-sensitive cells as humans. This is why cats can see so well at dusk. However, there must be a little light, in total darkness the cat cannot see anything either.
As sensitive as the cat’s eyes are to light, they don’t see pin-sharp. On the one hand, they are less able to adjust their eyes to distances and, on the other hand, they have a large angle of visual acuity compared to humans. The angle of visual acuity is a measure of the ability to separate two points that are close together.