How dogs see the world
Original Publication Date: August 10, 2015
By C. Sue Furman, Ph.D.
When you and your dog look at a red ball, do you see the same thing? You both see a round object, but you don't see exactly the same thing.
We look over a field of tall flowers and see beauty. From the perspective of a Dachshund, the field might look like a jungle.
In addition, our visual acuity is better than that of the average dog.
Like humans, dogs have specialized photoreceptor cells in the retina. Cones respond primarily to color while rods are more sensitive to light and movement. Very early research on canine vision reported that dogs were colorblind.
Recent studies show that dogs are not colorblind, but they cannot see all the colors humans perceive.
We have cones sensitive to green, red, and blue. Dogs only have cones that detect green and blue.
Dogs cannot see red so their vision is similar to that of a human with red-green colorblindness.
Despite CM Coolidge's well known painting of dogs playing poker, pups would no doubt do poorly at the game, because they can't see red. Your dog probably has no plans to play poker, but remember to be a little patient if you throw a red ball onto the green lawn, and it takes him a little while to find it. Red and green are basically the same color to him.
Perhaps you may want to consider color when you choose new toys for your friend.
Rods do not perceive color but are sensitive to light and dark changes, shape, and movement.
Dogs have more rods than humans, so canines can see better than us in dim light.
Dogs also have a wider degree of peripheral vision and are 10 to 20 times more sensitive at detecting motion at a distance than humans. These qualities give dogs in the wild an advantage when hunting fast moving prey at dawn or dusk.
A dog's eye view of the world is very different than ours, because height of eyes above the ground impacts his perception of his environment. A toy dog sees things from the level of our ankles, while a bit larger pup operates from the level of our knees.
A large breed Irish Wolfhound looks at things as we might see them if we had eyeballs in our belly button. Consider your dog's view when taking a walk.
Dogs tend to be nearsighted. The average dog's vision is 20/75 compared to a human's 20/20. If your visual acuity is worse than 20/40 you will fail the vision test for a driver's license. A person with 20/75 vision requires glasses. Pups manage well without them.
A dog's color vision, perspective of the world, and visual clarity are quite different than ours. Whether going on a walk or playing fetch, be aware of how your dog sees the world.
Sue Furman, Ph.D, has published two books and a DVD on canine massage and teaches classes in pet massage, acupressure, first aid and CPR. See her schedule and submit questions at HolisticTouchTherapy.com.