Which Colours Can Dogs See?
When it comes to distinguishing colour, a dog’s normal vision is most like a person who has red-green colour blindness.
Research leads us to believe that dogs see the world through a unique colour spectrum. Yellow and blue are dominant colours in dog colour vision. Blue, blue-green, and violet look like varying shades of blue. Shades of red and green probably look more like browns and grayscale to a dog.
To dig further, what is the cause of dog colour blindness?
First, you’ll need to understand how the eye works. The eye is made up of specialized cells and receptors called rods and cones. Rods are responsible for detecting motion and aiding vision in varying shades of light, while cones help to differentiate colour.
People have three types of cones, while dogs have two. This means that people can normally identify three colour combinations (red, blue, and green), while dogs are limited to two (yellow and blue). Dog colour vision is therefore described as dichromatic, or “two-coloured.”
This is exactly why your canine friend prefers toys in yellow or blue than in other colours.
Sources and references:
https://www.petmd.com/dog/general-health/what-colours-do-dogs-see
https://vcahospitals.com/know-your-pet/do-dogs-see-colour#:~:text=Dogs%20possess%20only%20two%20types,perception%20is%20called%20dichromatic%20vision.
Image from PETMD