A dog’s vision is closely related to that of a wolf. Domesticated dog breeds evolved from wolves many thousands of years ago. While they are now a different species, they still share many common traits.
Wolves’ highly evolved vision allows them to spot prey animals at long distances. Their vision also enables them to check the movements of the rest of the pack while hunting in a group. Wolves hunt at dawn and dusk. Along with a well-developed sense of smell, they have acute vision even in very poor light.
Dog’s Eyes vs Human’s Eyes
Dogs have inherited many of these traits from their wild cousins. They have wide, discriminatory vision and can see in low light conditions. That’s one reason they make such good guide dogs. They can see what’s going on all around them much better than even a sighted human can.
The breadth of a human field of vision is about 180°. If humans want to look at things on either side or behind them, they have to turn their heads and redirect their eyes. That’s because human eyes are close together at the front of the head. Dogs’ eyes are more toward the sides of the head. They have a breadth of field of between 250° and 260° depending on the breed. Certain breeds with slender heads and small ears, such as greyhounds, can see almost 360°.
Humans protect and clean their eyes by blinking, but they have only one set of eyelids. Dogs have a third set like birds and reptiles. It’s called the “nictitating membrane” and it’s practically invisible. The thin film of skin is pulled by a strip of cartilage across the eye, side-to-side. It polishes and moistens a dog’s eyes making sure the animal’s vision is always crystal clear.
Clear Up Any Confusion
A popular misconception is that dogs are color-blind. While their sense of color is not as distinct as that of humans, they can see the entire color spectrum. But although they can see color, research suggests that the color of an object is not as important to a dog as it is to a human when it comes to identifying that object.
The most common threat to your dog’s vision is from cataracts. Cataracts can develop at any stage of a dog’s life and are usually age-related, diabetes-related or inherited. While surgery can be an effective (but costly) correctional procedure, all surgery carries with it a measure of risk. Fortunately, as dog lovers, you and I have a safe, effective and completely natural alternative to the surgeon’s blade. Please consider our best-selling herbal remedy, Cataractin, for cataracts in dogs.