Cat vision is vastly different from human vision. Feline eyesight is specialized to help these nocturnal animals hunt at night. So, can cats see in the dark? And can cats see color? Read on to find the answers to that plus other interesting cat vision facts.
Can cats see in the dark? Not exactly. Cats need some light in order to see, but they only need one-sixth the amount of light humans do. Cats see so well in low light due to the design of their eyes. “The curved cornea and large lens direct light, and the pupils open to full circles to take in maximum available light,” says Hazel C. Carney, D.V.M., MS, Dipl. ABVP, of WestVet Emergency and Specialty Center in Garden City, Idaho.
“The tapetum increases available light to the cat. This is an extra layer of reflective cells in the retina that bounces light back to sensory cells so the retina receives 50 percent more of the available light.” The tapetum is the reason your cat’s eyes glow green when you take his photo with a flash.
Cats see about 300 degrees around their heads — that’s nearly a full circle! Each cat eye sees about 155 to 208 degrees, with 90 to 130 degrees of overlap. Cat eyes also detect very fast movement (4 millimeters per second). These traits help cats catch those tiny, fast-moving mice.
Although cats can see 120 feet away, 40 percent of cats cannot see within a foot of their noses. “On the eye chart, normal cats see about 20/60 to 20/100,” Dr. Carney says. To compare, normal human vision is 20/20.
Cats see colors, but the hues they see are not as varied or bright as the colors humans see. “They have a limited ability to separate colors,” Dr. Carney explains. “They see blue and yellow best; red and green fade into grays.”
Certain breeds like Balinese, Himalayan and Siamese, and/or mixes of these breeds, have higher incidences of cats being cross-eyed, but this doesn’t necessarily mean they have vision issues. “It worsens if the cat becomes excited or frightened and as the cat ages,” Dr. Carney shares. “We presume cross-eyed Siamese see what humans do when we intentionally cross our eyes, but because they see that all the time, it’s normal for them. My own Lynx-point Siamese-cross is very cross-eyed and can catch anything he hunts.”
“All cats with blue irises or non-pigmented tapeta have increased light sensitivity and may squint in response to suddenly encountering bright light,” Dr. Carney says. Blue-eyed white cats are also more likely to be deaf.
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This piece was originally published in 2017.
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