The Anatomy of a Cat's Eye
Compared to other animals, a cat's eyes are pretty unique, having special distinct features that set them apart. Large, intense and simply beautiful, a cat's eyes were built as devices to help capture the slightest movements aiding them to stalk and chase prey in the wild.
The most intriguing feature is the size of a cat's eyes. If we look at proportions carefully we will notice that a cat's eyes are significantly large when compared to the size of their head. This is typical of nocturnal animals, simply think about the disproportionally large eyes of an owl or a slow loris. Large eyes allow nocturnal animals to take in much more light when in dark habitats.
Saying that cats see well in the dark is really a half truth. While cats cannot see in complete darkness they can see pretty decently (about six to ten times better than humans) in an environment that we would consider dark.
The typical yet mysterious fluorescent shine a cat's eyes emit when caught in a beam of light is due to a particular structure called the "tapetum lucidum" located exactly right behind the retina. This structure works just as those reflective signs used during roadway construction or commonly used as lane markings on the highway, thus explaining why they are called "cat's eyes" as well. The cat's tapetum works like a mirror allowing lights to bounce out of it.
A cat's eye may feature an elliptical pupil when there is light and a round large pupil almost filling the whole iris area, when in the dark. The pupil is very sensitive to light changes and will adjust accordingly.
As mentioned earlier, a cat's eyes are specifically designed to capture the slightest movements. Have you ever found your cat looking up at something that is not there? No need to worry, your home is not haunted. Chances are your cat may have been able to visualize something as subtle as a spider web clinging in the air or a tiny bug.
As powerful and magnificent a cat's eyes may seem, they also have some flaws. One of them is the fact that a cat has a small blind spot area making them unable to effectively see objects directly in front of them or right under their nose.
Another major flaw is a cat's day time vision which is much more inferior to the day time vision of humans. Cats during the day will have poor focus and may see somehow blurry. Cats are also incapacitated in their ability to perceive vivid bright colors. While their color vision may not be vibrant as ours, they have shown to respond best to the following colors: purple, blue, green, while red appears to be the least perceived. However if we think about it, colors really do not seem to play a vital role in a cat's survival skills.
Cats also have a third eyelid. While this is not seen when a cat's eyes are wide open and the cat is awake, a hint of it may be seen when a cat suddenly wakes up from sleeping. The cat's third eyelid is located in the inward corner of a cat's eye. It appears as a whitish film that in some cases may almost cover the entire eye. However, the third eyelid should not show under normal circumstances. Protrusion of the third eyelid may need a thorough veterinary exam to verify the underlying cause.
A cat's eyes have played a vital role in the cat's many years of survival. They have allowed this magnificent animal to stalk, pounce and prey and it is ultimately thank's to a cat's eyes that we are able to enjoy our feline friend's companionship today.