Posted on: December 16th, 2016 by Dr. Melissa Mustillo
This time of year we pet owners are thinking about what to get for our cats as a holiday gift. What kind of toy would they like? And while pondering that question, I started thinking about cat vision and what my cat sees when she’s chasing a ball or getting ready to pounce on the mink teaser toy she has (or my toes, for that matter).
Cat eyes-how are they different from ours?
While the feline eye is similar to ours, there are notable differences. Feline eyes were designed with the night hunter in mind; one reason that cats have the largest eyes of any meat eater. I read a statistic that if our eyes were proportionally the same, human eyes would be eight inches across!
Placement of the eyes in the skull affects the animal’s ability to see. Globes that are placed closer together provide a greater degree of visual overlap as well as better binocular vision and depth perception. Predators like cats have eyes toward the front of the face, while prey animals like mice and deer have eyes on each side of the head so they can watch in two directions at once.
The colored portion of the eye is a highly specialized muscle called the iris. The iris opens and closes to regulate the amount of light that enters the eye through the pupil (the black central part of the eye). The human and dog iris is a simple circular muscle. The cat’s iris is a more complex figure-eight muscle. It can open larger and close to a slit that shuts out even more light than the canine eye. This allows the cat to focus even better. Have you ever wondered why cat’s eyes seem to have an eerie glow at night? That is caused by the tapetum lucidum, a layer of highly reflective cells behind the retina that reflects back any light entering the eye. Cats only need 1/6th the illumination level and use twice as much available light compared to people. Dogs’ eyes are about half as efficient as cats’ eyes.
Black and white–or in living color?
Now for the controversial question of whether cats see in color. The cone cells in your retina are responsible for visualizing color. Cats and dogs possess fewer specialized cone cells than people do. They can see in color, but it doesn’t appear to be as important to them. Cats and dogs appear to have fewer red-detecting cones as well, and mostly see in shades of blue, green, and yellow. While dogs can be taught to distinguish between certain colors, cats take longer to understand why color should matter. Cats most easily can distinguish between colors that contrast. For cats, pattern and brightness are more important than color.
Chasing everything that moves!
Both dogs and cats rely more on motion rather than focus. Cats are experts at seeing motion from the corners of their eyes and have about 155 degrees of peripheral vision. Cats also have a highly specialized ability to make extremely rapid eye movements. That allows them to better detect and follow an object, such as a mouse or a feather on the end of a string toy. That’s probably why mice instinctively freeze in the presence of a cat. Cats also have an instinctive urge to chase whenever something moves in their periphery vision.
I hope this helps you to better understand your kitty and how they perceive the world,
Dr. Melissa =^..^=