Are dogs colorblind? Just about everyone seems to think so, but is it really true? That’s what we’re going to figure out today! Here’s a scenario for you: You get home from work, give your dog a pat, and decide it would be fun to go outside and play a game of fetch. You grab his favorite red ball and head out into the backyard. It’s a beautiful early summer day – the sun is shining, it’s not too warm, and the grass is a beautiful shade of green. You toss the ball out into the yard for your dog to retrieve, and the next thing you know, your dog (who is normally great at fetch) doesn’t seem to see the ball. Shrugging it off, you grab a blue ball that is sitting on the patio, throw it into the yard, and your dog brings it back to you with no problem.
What’s going on here? You know your dog can see the ball since he found the blue one. Why did he have a hard time with the red one? You’re right – your dog can see color, but like most mammals, he has a hard time differentiating between red and green.
Are dogs colorblind?
An article published back in 2001 broke the misconception that dogs saw in shades of gray – up until that time, that was a common belief. Humans and some primates are capable of trichromatic color vision, whereas most mammals (including dogs) and dichromatic color vision. A smaller group of mammals have monochromatic vision, meaning they cannot see color at all.
So why can dogs see blue and yellow but not red and green? The two color systems (blue-yellow and red-green) are independent of each other and are perceived by different cone photoreceptors in the retina of the eye. Humans have three of these cone photoreceptors, while dogs have two. Therefore, dogs see color in the blue-yellow system but not the red-green system.
Some humans are unable to see the red-green color system, as well, so does that mean they are missing a cone photoreceptor? Nope. Color-blindness in humans (which affects 1 in 12 men and 1 in 200 women) is caused by a genetic mutation on one of the cone receptors.
Here’s what your dog sees in relation to what a human with normal vision sees:
Going back to the ball story, your dog can see the shape of the ball, but the red color blends in with the green of the grass. Now that you know this, perhaps play with the blue ball when you’re outside and save the red one for indoor activities.
While your dog doesn’t see color quite the same way you do, he doesn’t live in a world of gray. Instead, it’s a lovely world of shades of blue and yellow. And, it hasn’t seemed to stop him yet!