While it’s not uncommon for people to think dogs are color blind, it’s a dated belief that’s been disproven. Your dog may not see the exact same color variations as you do—or see colors as vividly—but she’s still able to perceive color. Read on as veterinarians explain the science behind dog vision and give us a glimpse into the world as seen through a dog's eyes.
What Is a Dog’s Vision Like?
An animal’s ability to process color originates in the retina, the thin layer of tissue situated at the back of the eye. The retina houses two types of photoreceptor cells (or photoreceptors) called rods and cones.
“Rods help us (and dogs) see objects in dim light and cones provide good vision in bright light. Since it’s easier to detect color in brighter light, cones are the photoreceptors that play a key role in how we perceive color,” says Dr. Karen Brantman, a board-certified veterinary ophthalmologist with Northwest Animal Eye Specialists in Washington.
In contrast to dogs, humans have special areas of the retina dedicated to cones only. These cone-rich areas increase our ability to see things with better clarity, including color, says Brantman. “This means that what dogs see at certain distances won’t be as crisp and optically clear as it is for humans. Since cones are needed for vision in bright light, and humans have more of them, the human retina is better equipped to see color more richly.”
Dogs have more rods, however, so although they don’t see color like we do, they have the advantage when it’s dark. “Since canine retinas are adapted for seeing in the dark, what they give up in image clarity and color richness in day vision, they gain in night vision ability,” says Brantman.
What Colors Do Dogs See?
Humans have three cone photoreceptors (red, green and blue) that allow us to see the full color spectrum. Most domestic mammals, including dogs, only have two cone photoreceptors, says Dr. Yasmin Martinez, lead veterinarian at the Arizona Humane Society’s Second Chance Animal Trauma Hospital in Phoenix.
Because dogs lack green cones, they confuse red and green colors, says Dr. Jessica Meekins, an associate professor of ophthalmology at the College of Veterinary Medicine, Kansas State University in Manhattan, Kansas. “This is the equivalent of red-green color blindness, where red and green appear as a similar shade of gray.”
What colors do dogs see, then? Mostly blue and yellow variations on the color spectrum, says Meekins. Instead, they rely on their other senses (like smell, sound, taste and touch) to distinguish red, orange, yellow and green objects that appear similar in color.
Are There Differences by Breed?
There is currently no evidence to show that one breed can see colors with more detail than others. There are, however, various factors that impact color vision, which Brantman says may vary by individual dog and between breeds. Aside from rod and cone density, “these factors include the layout and cells of the brain itself and the clarity and health of the eye. For example, cataract presence, health of the cornea or other parts of the eye.”
Some people believe sighthounds, such as Greyhounds, see better, says Dr. Steve Roberts, a board-certified ophthalmologist and owner of Animal Eye Center in Loveland, Colorado, but that’s probably because these breeds have been developed for their ability to use their eyesight more than other breeds that may be better tuned into their senses of smell and hearing. It would not impact the colors they see.
The world looks different to your dog than it does to you—she is unable to see that the lawn is green or that the shirt you’re wearing is red. In a dog’s world, however, color doesn’t hold the same meaning as it does to us.
Dog Vision Excels in Other Ways
Dogs do not have the clarity or sharpness of vision, also called visual acuity, that people do, so they compensate in other ways.
“Their reduced visual acuity means that they may not know that something just moved (for example, a piece of paper, leaf, toy or small critter), so they will typically move closer or use their senses of smell and hearing to figure out what moved,” Roberts says.
Additionally, dogs are very near-sighted, but they have a much wider field of vision and are able to detect motion much easier than we do, says Martinez. “These adaptations make them good at detecting fast moving prey.”