Canine FactsHealth

Dogs Are Nearsighted — But That Doesn’t Mean They Have Poor Vision

Dogs have the same five senses that people do: sight, hearing, smell, taste and touch. Some of a dog’s senses are far more powerful than ours, such as their ability to smell and hear. But there is a common myth that dogs have poor eyesight.

This article will take a look at how a canine vision has evolved.

Misconceptions about a dog’s sense of sight

Contrary to popular belief dogs do not see the world in black and white. According to an article about how dogs see the world compared to people, dog vision “is actually most similar to people with red-green color blindness.” Dogs also differ from humans in terms of sensitivity to brightness and variations in shades of grey.

In terms of visual acuity for humans, 20/20 is considered excellent eyesight. But the average visual acuity for dogs is 20/50. In other words, dogs are technically nearsighted. For a human, this would be considered impaired vision and require glasses.

So is their eyesight poor?

Because people have better visual acuity than dogs, some interpret this to mean that dogs have poor eyesight. Actually, dogs have perfect eyesight — for dogs. Consider this. The average bird of prey can see about eight times farther than a human, allowing them to see a rabbit or other critter from two miles away. That ability, however, does not mean that a human who cannot do the same has poor vision.

People do not need to see a rabbit from two miles away. Our type of vision works just fine for our needs as a species. In the same vein, dogs have perfectly fine vision for their survival needs.

Vision fit for a hunter

Dogs have an average visual field of about 250 degrees compared to our 180 degrees because their eyes are set farther apart than our own. Having a wide field of vision is what makes dogs such excellent hunters. Meanwhile, being able to see a wider spectrum of colors has no survival benefit if you’re a dog; so, it never evolved.

In addition to a wider field of vision, dogs also have better night vision than people and are better at picking up motion — another benefit for a hunter.

 

The moral of the story: Dogs do not have poor eyesight compared to people; they simply have a different kind of eyesight!