A cat's pupil changes shape due to the amount of light getting in.
Because of their shape and structure, a cats eyes are designed to capture all of the light possible, and it's eyes are able to see sixYou can read the full article from which the above quote was taken from here
times more then humans eyes can in the dark. The cat's pupil is a characteristic of cats in general. When a cat is in the dark, it's
pupils open automatically and this allows more light to come into its
eyes. However when there is a lot of light, the pupils close until they
look almost like a vertical line, and this does not allow as much light
to come into them. Also believe it or not, a cats pupils change in size
depending on their mood.
Are you asking about the "pupil" of the eye? Cats pupils are slanted naturally. When they are in bright light the pupil draws up into a small slit because the eye does not need to take in a lot of light. If a cat is in dim areas of light, then the pupil opens up in more of a round shape to let MORE light into the eye.
I guess what I am trying to ask (the question above is mine) is not why her pupils dilate but why are they not shapes like all the other cats I have seen. I have never seen a house cat with round pupils. She almost looks like an owl and she never blinks. I afraid she is a mutant or an alien.
Since the original poster's question was 2 yrs ago, they probably got the answer by now even though I'm trying to find out the same thing. One of my cat's are never completely round but more like a fat-type diamond shape when they dilate & a slit when they are the extreme opposite and my other cat (which is partly Siamese) dilate to a complete round/circle shape and when not dilated, they are a very small circle.
I don't know because my kitten has round pupil and blue eye's but they used to be real cat eyes! And his face is like really big and its kind of like a human face... I think its albino but I'm not for sure, because it has round eye's and that really freaks me out!!! I don't know
Basically, a cat's eyes react to light in much the same way as a human's. Off course, cats can see a lot better in the dark because their pupils dilate more to allow more light into the eye.
I don't know either but my mother-in-laws cat has big round black eyes and they never get smaller! It is like looking into a big black hole it really freaks me out I have a hard time looking at her!
The question is not about them being dilated to big round circles. The question is why when in bright light do they not go to small slits (traditional cat eyes) instead they stay big and round. Pay attention people.
This all depends on the breed of animal. Ever notice same for humans. While people have an average of 3 folds in lids, so they open wider and appear more round, while as asians, have no folds, so their eyes appear slanted. If you look at people of italian decent, you will notice in their painting, eyes bulge and wide. It is just character traits of different people and animals
Ok folks, I ran across this forum and wanted to throw my 2 cents in. It sounds like what are describing (the pupil always being round whether dialted or constricted) is a feature that majority of non-domestic cats have. The fact that at least one person is describing a cat with a fairly flat face, my educated guess would be that your cat has a parent, grandparent, great grandparent, etc. That is a Pallas cat (aka Manul). These are one of the oldest species of cats and are roughly the size and shape of a Persian with the exception of its' ears and overall coloring. These cats have a true round pupil, not a vertical slitted pupil like domestic cats. Hope that helps and if my theory is right, that's really really cool!
Dilated pupils are big and round and this happens in darker rooms and at night. A cats pupils will constrict, becoming slits, in bright light. This is normal. I'm surprised you haven't seen your cats eyes be big and round before.