Dogs do not see everything in black and white; however, they do not have a full spectrum of color vision like humans. The ability to see different colors is a result of neuron cells in the eye that send signals to the brain after recognizing a color. Human eyes contain three types of cells that detect color, known as cones, while dogs’ eyes only have two cones. This allows dogs to view shades of yellow and blue, but not any colors on the red to green spectrum. Since dogs don’t have the cones that detect red and green, their neurons don’t make any signal to the brain and the default is for the brain to perceive it as shades of gray.
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