- From research by perception psychologists, scientists theorize that dogs mainly see in yellows and blues, along with white, black and gray. This type of vision is called dichromatic.
- Dogs most likely see shades of red and green as different shades of gray, perhaps yellowish or brownish, or even white or black depending on how light or dark the color is.
- Fewer cones also means the color vision of dogs is not as intense, and some colors blend. Orange is probably seen as yellow, and blue-green as gray.
- Studies such as one published in a 1989 issue of Vision Neuroscience research behavior discrimination in dogs to confirm dichromatic vision. Researchers trained dogs to choose the one different color in a group of three lights, rewarding the dogs with a treat when they chose correctly.
- Dichromatic dog vision makes it especially clear that different-colored dog treats and certain colors of toys are designed to attract people, not dogs.









