Dogs have very different vision compared to humans. Their eyes are specially adapted to detect movement and help them hunt. But does this mean they only see the world in black and white?
How dog vision compares to humans
Humans are trichromats, meaning we have three types of color receptor cones in our eyes. These allow us to see the full spectrum of color, detecting red, green and blue light.
In comparison, dogs are dichromats. They only have two types of color receptors. This means they can’t distinguish between red, orange, yellow, and green light like we can. Their vision is similar to red-green color blindness in humans.
So essentially, dogs see the world in just two main colors – blue and yellow. This is why dog toys and treats are often bright blue or yellow, as these stand out well to dogs.
Do dogs see only black and white?
While dogs don’t see the full range of colors, it’s a myth that they only see in black and white or shades of gray. Their eyes contain special structures that allow them to detect some color.
The two color receptors in a dog’s eyes are sensitive to blue and greenish-yellow light. When combined, these allow dogs to see some colors in the blue-yellow color spectrum:
| Colors dogs see best | Colors dogs see poorly |
|---|---|
| Blues | Reds |
| Yellows | Greens |
| Grays | Oranges |
| Purples | Pinks |
While not as vivid as human color vision, dogs do have some color perception. Their world is not entirely black, white, and shades of gray.
How well can dogs see color?
Research suggests that although dogs have limited color vision, they can distinguish between some colors in the blue-yellow range:
- Dogs can tell blue from gray.
- They can discriminate between different shades of blue.
- They can distinguish yellow from gray.
However, studies show dogs struggle to tell apart similar shades in the yellow-green-red range. They group these into a single yellow category.
So while not strictly colorblind, dogs don’t experience visual richness and diversity of hues like humans do. Their world consists mainly of blues, yellows, grays and shades in between.
Why do dogs see limited color?
There are several theories as to why dogs evolved with dichromatic vision:
- Hunting ability – Seeing a “lower resolution” of color may help dogs better detect camouflaged motion and track prey.
- Light sensitivity – Having fewer cone cells allows more rods, which aid vision in low light.
- Evolution – As most canines are red-green colorblind, this may be an ancestral trait passed down over time.
While some debate exists, most scientists believe dichromatic vision gives dogs an advantage for tasks like hunting. The limited color perception is likely an evolutionary adaptation.
How dogs compare to other animals
Humans have exceptional color vision among mammals. But how does dog color perception compare to other animals?
- Cats – Also dichromats, but may have superior blue color detection to dogs.
- Bulls – Dichromatic like dogs, but possibly with greater color distinction abilities.
- Monkeys – Most are trichromats like humans and see the full color spectrum.
- Mice – Some dichromats, some monochromats who only see black and white.
Research suggests dogs and cats have similar dichromatic vision. Primates like monkeys see a wider range of color like humans. Rodents like mice have even less color vision than dogs.
Do dogs see color when dreaming?
Dogs experience dreams and REM sleep just like humans. But do their dreams contain color since they see a limited color spectrum when awake?
Unfortunately, we cannot know exactly what dogs see in their dreams. But scientists guess their dreams are also limited to mostly grays, blues and yellows – consistent with their waking vision.
However, we can’t rule out the possibility that the dog brain “fills in” additional colors they aren’t able to see when awake. Their dreams may contain a fuller range of colors than they actually experience.
How to choose toys and treats for colorblind dogs
Knowing dogs see a limited color palette can help you better choose toys and treats to entice your pet:
- Pick bright blue or yellow toys they can easily spot.
- Avoid red, green or orange toys that are hard for them to see.
- Choose blue or yellow treats like cheese or banana chips.
- Don’t rely on red or green food coloring as cues – use smell instead.
You can give your colorblind dog the best chance of finding their new toy or treat by using colors they can easily perceive.
Should you train dogs based on their color vision?
Dogs with normal vision can be trained to understand color names and commands. However, it’s best to stick to colors they actually see well:
- Train them on “yellow” and “blue” but not red or green.
- Use a blue toy then reward them for fetching the “blue” one.
- Praise them for targeting the “yellow” frisbee instead of a gray one.
Dogs can learn colors based on their more limited visual spectrum. But don’t expect amazing results training them with red, green and other difficult hues.
Should certain breeds be tested for colorblindness?
Most dogs only have dichromatic vision. But there are rare cases of colorblindness:
- Monochromacy – total color blindness, seeing only shades of grey.
- Other visual impairments like diminished blue perception.
These conditions are extremely uncommon in dogs but can occasionally occur. Some experts recommend testing herding breeds and other working dogs that rely heavily on sight.
For pets, testing is probably not needed unless you notice signs of visual impairment. But for dogs like herders and military/police dogs, ruling out monochromacy can be important.
Conclusion
While the myth persists that dogs only see black and white, the truth is their vision includes limited color perception. Dogs are dichromats, meaning they have two color receptors compared to humans’ three.
This gives dogs the ability to see some colors in the blue, yellow, gray and purple range, but reds, greens and oranges appear dull or indistinguishable. Their view of the visual world is significantly less colorful than human sight.
But although more muted, dogs do have partial color vision that likely aids their hunting and survival abilities. So no, dogs do not see a colorless world of merely black, white and shades of gray.