Grass may appear as a vibrant green to humans, but what about to our four-legged friends? Dogs see the world differently than humans due to differences in their eyes and visual system. If you’ve ever wondered what color dogs see grass or other aspects of their world, read on to satisfy your curiosity.
If you’re short on time, here’s a quick answer: dogs see grass as various shades of yellow and blue due to their dichromatic vision. They don’t see the same green color that humans with trichromatic vision can see.
An Overview of Dog Vision
Dogs are Dichromats
Unlike humans who have trichromatic vision and can see three primary colors, dogs are dichromats, meaning they have two types of color receptor cells (cones) in their eyes. This allows them to see blue and yellow shades clearly, but they struggle to distinguish between red and green hues which appear more muted or gray to a dog’s eye (the grass looks yellowish to them rather than green).
While a dog’s color vision isn’t as vivid as a human’s, what they lack in color perception, they make up for in low light sensitivity thanks to a high concentration of rods in their eyes.
Dog Eyes Have More Rods Than Cones
The canine retina contains substantially more rod photoreceptors than cones. Rods allow dogs to see well in dim light, perceived by humans as darkness. So while their color vision is limited, dogs have excellent night vision and motion sensitivity allowing them to detect movements and track objects in light conditions that humans would find visually challenging.
This is an evolutionary adaption as dogs originally lived and hunted outdoors. Having superior night sight and noticing movements quickly gave dogs an advantage for survival over prey animals active in twilight or at night.
Differences Between Dog Breeds
While all dogs have dichromatic vision, visual abilities can vary significantly between breeds. Working breeds like Greyhounds have better vision overall with a wide field of view and ability to spot fast movements compared to Brachycephalic (short-nosed) breeds like Pugs whose flatter faces limit their visual scope.
According to a 2016 study published in the PLOS One journal, sight hounds like Greyhounds scored higher at tasks related to motion detection and sensory perception compared to other breeds studied (reference).
So next time you play fetch with your furry friend, consider their unique visual abilities!
What Colors Can Dogs See?
Dogs have a different visual system than humans, which allows them to see the world in a unique way. Their color vision is limited compared to humans, but they make up for it with superior night vision and an ability to detect motion.
Understanding how dogs see colors can provide insight into their behavior and perception of the world around them.
Dogs See Mainly Yellows, Blues and Grays
The canine retina contains only two types of color receptors (cones), specialized for yellow and blue. This is why dogs see the world in primarily yellows, blues and grays. Their color vision is similar to people with red-green color blindness.
Dogs are essentially “color blind” to hues of red, orange, green and purple.
However, dogs have more rods in their retina, which enhances their ability to see in low light. They also have a wider field of vision than humans do. So while their color perception is limited, their vision excels in other ways that are useful for their survival.
They Struggle With Red and Green
Humans have three types of color cones, allowing us to see the full spectrum of reds, greens and blues. Dogs lack the photoreceptor cones to detect shades of red and green. Research shows that dogs mainly see these colors in hues of gray.
For example, a green tennis ball or a red frisbee may appear grayish-brown or dull yellow to a dog. Bright red or green food toys may appear neutral to them as well. So dogs rely more on brightness, saturation and contrast rather than color for their visual cues.
How This Affects Their View of Grass
Grass appears primarily yellowish or blue-green to dogs rather than the green that humans see. However, the shade of grass varies based on factors like moisture, health, species and sunlight exposure. So dogs likely perceive different grass types in differing shades of blue, yellow and gray.
| Humans see… | Dogs see… |
| Bright green grass | Yellowish-tan or light gray |
| Dry, yellow grass | Blue-gray or darker gray |
A dog’s view of lush green grass lacks the vivid green color visible to human eyes. But while they can’t appreciate the green hues, dogs can still enjoy the feeling of soft grass under their paws and smell its fresh scent!
Why Dogs See Grass Differently Than Humans
Humans Have Trichromatic Vision
Humans are trichromats, meaning we have three types of cones that allow us to see color. The three types of cones are sensitive to short (blue), medium (green), and long (red) wavelengths of light. This trichromatic vision allows us to see the full spectrum of colors from violet to red.
We can differentiate between millions of different shades and hues.
Dogs Only Have Two Types of Cones
Dogs, on the other hand, are dichromats. They only have two types of cones – those sensitive to blue and green wavelengths of light. This means dogs can only see blue, green, some yellows and grays. So dogs have a much more limited color vision range.
They see the world in fewer hues and with less richness of color variation.
Dogs Rely More on Movement Than Color
Because of their limited color vision, dogs rely more on brightness, contrast, and movement to see. The grass may all look about the same greenish-gray color to them. But when the grass moves in the wind, or an object moves across it, the contrast grabs their attention.
So dogs are less interested in the color of grass than humans are. Grass is just the backdrop. The action and movement happening in it is what really catches a dog’s eye.
In fact, studies show dogs notice moving objects 5 times faster than stationary objects. Their eyes are better adapted at detecting movement and locking in on stimuli that catches their attention. Color vision takes a back seat to motion detection for dogs.
So for your pup, the grass is not so much green as it is a place to run around and play in. Dogs are more excited about grass for the smells, textures, and fun they can have in it than its actual color.
So while humans may obsess over having a lush, green lawn, dogs are just fine with the grass being any old color.
How Dogs Use Their Vision
Tracking Movement and Reading Body Language
Dogs have excellent vision for tracking movement and reading body language. Their eyes have more retinal ganglion cells than humans, which are the cells responsible for detecting motion and sending visual information to the brain.
This makes dogs very sensitive to movements and allows them to detect even subtle changes in a person or animal’s posture and gait, which gives them insight into mood and intent. Dogs use this visual ability for hunting, playing, and communicating with other dogs and people.
Making eye contact with a dog can signal aggression or friendship, staring may provoke a reaction, and breaking eye contact signals non-threat in canine communication. Reading body language through vision is second nature to dogs.
Seeing at Night With Their Rods
One of the advantages dogs have in their vision is the high proportion of rods in their retinas. Rods detect motion and light levels, allowing for vision in dim lighting. Humans have more color detecting cone cells, whereas dogs have far more rods for night vision and motion detection.
This means dogs see very well in dark conditions when humans would be near blind. According to WebMD, dogs have a minimum light detection threshold that is six times lower than humans, and their eyes have a special structure for letting in more light.
Their wide field of vision due to the placement of their eyes also aids their night vision by giving a larger area of light intake. So when it seems pitch black to you at night, your dog has the advantage of seeing what’s around them due to their amazing rods!
Using Their Nose Along With Their Eyes
While a dog’s vision is not as sharp and colorful as human sight, dogs make up for visual weaknesses by using their legendary sense of smell. The area of a dog’s brain devoted to analyzing smells is about 40 times greater than in humans!
According to the American Kennel Club, dogs have 25 times more scent receptors than people. So dogs rely heavily on their nose to identify objects, people, and surroundings. But they use their eyes and nose together for locating.
For example, if a dog smells their favorite treat, they will use vision to quickly spot the exact location and source of the smell. Their wide field of vision allows dogs to scan an area while using their nose, then lock in on the target visually.
This combined use of scent detection and vision makes dogs highly effective at locating items or people, even if out of plain sight.
Conclusion
To summarize, dogs don’t see the exact same colors as humans due to their dichromatic vision. Their world consists mainly of yellows, blues and shades of gray. So for your canine, grass likely appears as various shades of yellow and blue rather than the green that humans see.
While dogs don’t rely primarily on color vision, their excellent motion detection and night vision allow them to thrive. Their eyes work together with their powerful sense of smell to create a complete picture of their world.
Understanding how dogs experience vision gives us insight into our loyal companions. Next time you’re outside with your pup, consider how the grass, trees and sky may differ in their eyes compared to your own.
