In the 2001 movie Cats vs Dogs, a “Secret Agent” dog is attempting to disarm a bomb when he is instructed to “cut the red wire.” The frustrated canine replies, “We’re dogs! We’re colorblind!”
The camera then shows a “dog’s eye view” of the world — in grayscale.
What the moviemakers didn’t realize is that actually, dogs can see color — and a theoretical bomb-disarming dog would see the difference between a red wire, a blue wire and a yellow wire! (Let’s put aside the question of whether our pets are also capable of waging a covert canine-feline war over the affection of humankind).
A more recent example from popular culture of the “dogs only see gray” myth comes from a brief scene at the end of the 2009 movie Up: As the movie’s human characters are naming the colors of passing cars (saying “Blue one!” or “Red one!”), a talking Golden Retriever named Dug chimes in with “Gray one!”
Yet contrary to popular belief, dogs are not completely colorblind, and do not see the world in only black and white. This persistent misconception originated in the 1930s and has survived in popular consciousness nearly a hundred years later — despite scientific evidence to the contrary.
The Science of Sight
The answer to the question, “Can dogs see color?” was proven to be “Yes!” in a scientific study in 1989.
Researcher Jay Neitz at the University of California, Santa Barbara, trained a group of dogs (including his own poodle, Retina) to push a button in exchange for a yummy treat. He then gave the dogs three buttons to choose from: two of the same color, and a third of a different color. Only by pressing the “differently colored” button could the dogs earn a treat.
If dogs can truly only see in black and white, then Neitz’ test pups should have been guessing randomly, and only selecting the correct button around 33% of the time (by chance). But what Neitz discovered is that on some combinations (such as blue vs yellow, or blue vs red) the dogs successfully chose the “different” button nearly 100% of the time — proving that they could see the difference!
Through this simple yet ingenious test, Neitz worked out which colors the dogs could and could not see.
Neitz’ pup Retina would choose randomly in this example, as she can’t see the difference between red and green.
Science now knows that dogs are dichromatic. That means their eyes contain two types of cones, which are the specialized nerve cells that detect color.
Dogs’ eyes have cones for blue and yellow, so they can see these two colors, and any other shades formed by the overlapping wavelengths. By mathematically calculating the possible combinations of these two, scientists have determined that dogs can see around ten thousand distinct shades of color.
Humans, by contrast, are trichromatic. Our eyes contain three types of cones: red, blue and green. Since there are many more wavelength combinations possible with three cones instead of just two, humans can see around a million distinct colors — that’s a hundred times as many as dogs!
(What’s truly wild is that there are some animals, like birds, that have even more cones than us! Birds are tetrachromatic, so they have four cones — and can therefore see a hundred million colors, most of which are literally impossible for humans to imagine. To a bird, we are severely colorblind!).
Basically, dog color vision is similar to that of a human with severe red-green color blindness, a condition where someone is born with a deficient number of red or green cones.
If you’re familiar with this condition in humans, you know that color-corrective glasses do exist which allow some people with red-green color blindness to perceive a wider spectrum of colors. But don’t bother putting in an order for a pair for Fido — sadly, they don’t work on dogs!
What Dogs Really See
So, what colors can dogs see?
Red, green, and orange all look yellowish-gray to your dog. Colors in the blue family (blue, purple and indigo) all look blue. Bright yellow looks…well, yellow, actually!
So when your dog looks around, the color blue stands out to them the most, with yellow taking a close second.
This is why, if you ever watch dog competitions such as agility, you’ll notice that the ramps, poles and other items on the course are usually blue and yellow. These colors stand out very strongly to dogs, since they see almost everything else as yellowish-gray.
Remember that the next time you laugh at your dog for obliviously running straight past the red Frisbee you threw. To your pup, it simply blends into the green grass! (Sorry, Fido!)
Unfortunately, most dog toys tend to be red or orange, a marketing decision that was made with humans in mind: we like the color red. People find red bold and appealing; your dog, however, isn’t as impressed. (It’s possible, of course, that your dog does have a red toy that they adore — but that’s probably because of its smell, texture or other features, not because of its color).
Basically, if dog toy manufacturers want to cater to their canine customers, they should steer clear of red and make dog toys blue or yellow instead (or better yet, a contrasting pattern of both).
By the way, tennis balls were only designed to be yellow because that color was most visible to fans watching the match on TV — but perhaps that bright yellow hue has helped tennis balls become one of the most popular dog toys in the world!
Outside of the rainbow, black-and-white also stands out to your pup, so they’ll be able to clearly see that soccer ball or toy penguin.
If you’re curious to look at the world through Fido’s eyes, you can do so with an app called Dog Vision, which uses the latest scientific research to make the best approximation possible of what your dog really sees.
Though our canine companions lose out on color, they do trump us on other visual abilities. For example, dogs are better than we are at detecting motion, so they can track that squirrel darting through the backyard faster than you can. They also have a wider field of vision than humans (depending, of course, on the shape of their head and how forward-facing their eyes are).
Dogs also see much better in the dark than we do. It’s obvious how this trait would be helpful to your pup’s wolf ancestors, who did most of their hunting at dusk. That means when the lights are off in your house, your pup can probably navigate the furniture just fine — though you may be stumbling blindly!
Of course, the downside of superior night vision is that during the day, what would be a comfortable light level for humans probably seems too bright to our dogs. If it was up to Fido to choose, he’d want to dim the lights — similar to how you feel when you go outside on a bright summer day without sunglasses on and have to squint a little bit.
Sadly, dogs are also more near-sighted than most of us. A visual acuity score of 20/20 is considered normal for humans, and 20/30 or 20/40 would be typical of a person who wears corrective lenses. Our poor pups, however, have a visual acuity score somewhere in the range of 20/75 or 20/80 — so their world is far blurrier than ours!
Smell to the Rescue
It may distress you to know that in many ways, your best furiend can’t see nearly as well as you can. But before you start drawing the curtains over the windows and replacing all red objects in your house with blue ones for the sake of your pal’s visual comfort, remember that overall, vision is not quite as important to our dogs as it is to us.
Dogs rely much more than we do on their hearing and especially their sense of smell, and their capabilities in both of those areas leave us in the dust. In fact, if Fido knew how pathetic your own sense of smell was compared to his, he might pity you. After all, there’s so many amazing scents you’re missing out on — how do you live??
At the end of the day, what’s important to remember is that our dogs can navigate the world just fine — and when your best furiend gazes adoringly at his favorite person, he may not see the green shade of your eyes, but he definitely knows it’s you.
(And yes, your pup will find that lost Frisbee eventually — he just needs to sniff it out first!).