Is dog's eyesight better than human's?

jkoch

By Dr. John Koch

Question: I know that dogs have the ability to both hear and smell better than their human masters. However, after having observed several dogs over the years I have come to the conclusion that humans see better than dogs. Am I correct?

Answer: In some ways you are correct. Dogs do not see detail as well as humans. Dogs will not notice how bushy your eyebrows are. They will not notice the size or shape of your nose or ears. You can smile or frown and your dog won't notice the difference. All of your fine facial features will not be observed. In fact it is felt that dogs have about six times less the ability to identify fine features than their human counterparts.

Most humans have the ability to see a wide range of color. Dogs see a limited range of color. It has been established with reasonable certainty that dogs only see blue, yellow and gray. If you are a human with red-green color blindness, then you see color in much the same way as your dog.

Dogs have larger pupils and lens than humans do; however, their lens does not have the ability to focus on items at different distances. Survival throughout the ages has not required dogs to have this ability, and it has never been developed.

What dogs do have that humans don't is the ability to gather or collect light so that they can see in very dim light. This very important ability along with their acute hearing, keen sense of smell, and social propensities have enabled dogs to meet their challenges throughout time.

Their traits and sharp senses have helped dogs endear themselves to humans. Today canines are used as Seeing Eye dogs, as watchdogs warning of intruders that make the faintest of sounds, as bomb or drug sniffing detectives, and of course, as family pets or companions.

Dr. Koch is a Cape Girardeau veterinarian.