As you watch your cat, basking in the sunlight on his favorite windowsill perch and looking out the window, you might wonder what he is watching. What does his world look like? Does he see in color? How does his vision differ from ours? Scientists are still researching all of these questions but have discovered some interesting answers.
Of Cones and Rods
The retina of the eye contains cones and rods, two types of nerve cells that affect how a person or an animal views the world around them. Cones are responsible for the perception of color and work best in bright light. Rods allow the eye to detect motion and are more sensitive in dimmer light.
Both humans and cats have three types of cones that detect the colors red, green and blue, and combinations of these hues. Humans, however, are able to perceive a wider spectrum of colors simply because their retina has 10 times more cone cells as compared to cats. Cats do perceive colors but, because they have fewer cones, they perceive a fewer range colors. Scientists believe that the feline species can see blue, gray and possibly yellow. And so while your cat may not view the world as colorful as you do, it does not see in black and white either.
Cats have excellent night vision thanks to the large number of rod cells in their retina. They have 6 to 8 times more rods than the human eye, giving cats the ability to see well in dim light and the ability to detect motion more accurately in the dark.
Cats vs Human
Cats are nearsighted which means that what people can see clearly as far as 100 to 200 feet away, cats can only clearly see less than 20 feet away. Cats also have a wider range of peripheral vision since their eyes are set on the sides of their head. Unlike the 180 degree view offered by human eyes, cats enjoy a 200 degree view.
The shape and structure of a cat’s eye enhance their night vision. They have a larger cornea and elliptical pupils which allow more light in when dilated. Cat’s eyes also have a tapetum, a layer of tissue that scientists think reflects light back to the retina, making it possible for the eye to change the wavelength of the light received. This reflection also explains why your cat’s eyes seem to glow in the dark.
Playing With Your Cat
If you are shopping for a toy for your cat you may want to choose a blue, gray or a yellow one, as opposed to a red or green colored toy. And, next time you see him watching out the window, try to imagine what he is seeing through his eyes.