When you live with and care for a dog, you naturally have questions about his health, well-being and preventative care. Dr. Kevin Fitzgerald has answers.
Q: Do dogs see in color?
A: Your question is one of the most intriguing and frequently asked that I have experienced as a veterinarian. Just how well and what dogs see has been a much-debated topic for decades. The canine eye is well-developed, roughly the same size in all breeds, and about the same size as ours. Certainly there are many similarities between the eyes of people and the eyes of dogs. Nevertheless, there are many fascinating differences.
For vertebrates, structures in the retina (rods) help with discriminations in brightness, and another retinal structure (cones) help determine color. Humans have three types of cones (red, green, and blue) and dogs have only two (green and blue). Furthermore, dogs lack the number of cones in the retina that are found in humans. As a result, most researchers believe that dogs lack the color discrimination that is found in humans.
However, dogs have certain anatomical adaptations that give them many visual benefits that we lack. First, dogs have more rods than people do. As a result, they see better in the dark and their eyes adjust to the dark faster than ours do. Second, our eyes are positioned fully on the front of our faces. Subsequently, our field of vision is around 180 degrees maximum. A dog’s eyes are much more on the sides of the skull, giving them a field of vision somewhere between 240 degrees and 280 degrees. Wild dogs are crepuscular animals—they hunt at dusk and at dawn when prey objects are most active. In addition to having much keener vision in darker light, the canine eye is very motion-oriented. Their eyes are much more keyed in on moving things. The movement of an object is more important to a dog than its shape. Finally, dogs are social animals. Wild dogs have good capacity for facial recognition in distinguishing pack members. Our domestic dogs use this important visual skill in identifying and distinguishing human family members.
Although we often pity dogs for lacking the color-distinguishing abilities that we possess, their eyes actually give them several advantages. They do much better than we do with far less light and, although their nose beats out their eyes as the most important sense, they still see fairly well.
The eye has been called the “window to the soul” and vision called the “queen of senses.” Many of the same problems and disease processes that affect human eyes attack the visual organs of canines. Any damage or injury to the eye is potentially dangerous and your veterinarian can help safeguard your dog’s eyes and vision. Board-certified veterinary ophthalmologists can also help protect your dog’s eyes. Early detection is critical for a favorable outcome for many ophthalmic problems.
Originally published in AKC Family Dog.
Kevin Fitzgerald is a staff veterinarian at Alameda East Veterinary Hospital in Denver and is featured on Animal Planet’s E-Vet Interns.