The pupil is the opening in the center of the iris that allows the light to penetrate the eye and allow us to see what surrounds us. Humans have circular pupils, but there are different conformations, one of which we can find in domestic cats. But have you ever wondered why cats have vertical pupils?
The eye is the visual organ by antonomasia of complex organisms. Inside, right in the middle of the iris, there is a dark structure called pupil. The latter is an orifice, black due to the total absorption of light, used to modulate the light radiation and its uptake within the eyeball.
Its diameter may vary due to the action of dilated muscles, which allow a greater or lesser influx of light, depending on the light exposure. If the pupil dilates, it allows a greater passage of light in semi-dark conditions, if the pupil narrows it limits the amount of light that flows into the eyeball under conditions of excessive light exposure.
In humans, this mechanism is visible, but in night predators and twilight predators it appears much more pronounced. Analyzing the eye of the cats, in particular of the cats, we can note that the structure of the pupils takes on a vertical conformation. This characteristic makes the eye of the felines one of the most accurate and precise instruments for regulating the luminous influx.
The reason behind the vertical structure of cats’ pupils lies in the hunting methods implemented by the felines, according to an Anglo-American study led by Martin Banks, researcher at the University of California, Berkeley.
Cats, like all members of the family of felids, are stealthy and tend to be nocturnal predators, who implement ambush strategies. The vertical conformation, possessing the ability to expand in the dark much more than the circular one, gives predators an unparalleled night view. In connection with the venatory attitudes of adorable domestic cats, did you know why the domestic cat continues to hunt?
Moreover, by blurring objects in the background and focusing on the point of interest, in association with the angle of the individual eyes in a simultaneous image, this structure allows to evaluate with extreme precision the position of a prey in the immediate vicinity, allowing the est
“This is the right arrangement to maximize stereopsy and blurring as signals to evaluate distance simultaneously,” said Banks.
The study, besides analysing the peculiarities of the eyes of these predators, also verified the different conformations of pupils in various animal species.
Prey, in fact, possess pupils with a very different conformation. If we consider sheep and goats, for example, we can see a horizontal pupil pattern. This characteristic allows sheep to have a wide horizontal vision, useful for scanning the surroundings in search of hungry predators.
A further effort of the study was to define the relationship between the different types of pupils and the food role associated with these discrepancies.
Night predators tend to show vertical pupils, with a strong capacity for dilation to exploit the residual light in dark conditions and effective instruments for measuring the position and distance from the prey.
On the other hand, the preys have developed horizontal pupils to scan the surroundings and defend themselves from predators. According to researchers, a horizontal pupil tends to maximize an overview, together with the lateral position of the eyes that greatly enhances its effectiveness.
Banks confirms “It allows them to see better in front and back, and perhaps not be dazzled by the sunlight from above.”
Finally, scientists point out that circular pupils, such as human pupils, are a characteristic of predators who can act both in night and day conditions, being less bound by previous conformations \”more stringent and specialized.
If you are a lover of these fair and noble creatures, we recommend you take the fascinating journey into the world of cats.