Haven't we all, at some point, longed to see the world through our dog's eyes? Well, a viral TikTok filter now makes it easier than ever to see our surroundings in dog vision! Better yet, it can help owners to better outfit their homes in a manner most visually striking to their canine companion.
Though you may have grown up hearing the myth that dogs only see in black and white, this assumption has since been scientifically disproved. Like humans, a dog's eye makes sense of visual input via two main types of cells in the retina: rods (to discern light levels and motion) and cones (to differentiate color). Whereas humans have three types of cones, dogs only have two (blue and yellow).
Thus, dogs do have a slightly more limited range of color perception than us - making them red-green color blind. For reference, a red ball on green grass would appear in shades of yellowish-gray through canine eyes.
Drawing attention to this variance in color perception, TikTok's dog vision filter has allowed owners to better understand why their pup prefers certain rooms in the house over another, pick out the most visually enticing chew toys, etc.
One creator, Rose Crossman, got over 3.4 million likes showing off the inviting, cozy hues of her dog-vision-friendly bedroom.
Night Vision and Detecting Motion
No doubt, dogs have the evolutionary edge when it comes to seeing in the dark. Scientifically, there are two main reasons why our pups have superior night vision compared to human eyes. The first of which is that they have more rod cells in their retina, which are responsible for low-light vision and contribute to a canine's enhanced detection of motion and shapes.
Secondly, a dog's eye has a reflective tissue beneath the retina called the tapetum lucidum, which is responsible for that eyeshine or 'glowing eyes' effect when our pups are in the dark. Since humans lack this eye feature, our eyes tend to appear red in flash photographs due to a vascular layer behind the retina called the choroid.
Dogs also one-up humans with a wider field of view, ranging 250-270 degrees, compared to our 180 degrees. Due to broader peripheral vision, our pups are much more efficient at detecting movement. In fact, a dog's motion sensitivity is 10 to 20 times greater than that of its owner.
That said, most dogs have a visual acuity of 20/75 (with some breeds like Labrador Retrievers ranging closer to 20/20). Subsequently, though your pup is apt to pick up on a squirrel from a mile away, they're ultimately sensing movement rather than reacting to fine detail in the distance.
Another important distinction of dog vision is depth perception. Since a dog's eyes are placed more to the sides of their head, they gain a wider field of view, but, in turn, have less binocular overlap between their two eyes, which is required for depth perception.
Unsurprisingly, a dog's depth perception is best when looking straight ahead at an object. However, this is often not ideal because their nose tends to get in the way of their visual field! Further, depth perception can vary per dog breed. Canines with more wide-set eyes (like pugs) are naturally predisposed to have less accurate depth perception than other breeds whose eyes sit closer together.
In all, though eye placement is key, puppyhood as a whole entails not-so-great depth perception. This explains why pups may be hesitant to traverse down the stairs or jump down onto the floor. Understandably, it can be very intimidating for puppies to brave the stairs when they can't make out individual, descending steps!
Circling back to a dog's color vision, the ASPCA Adoption Center in New York found that pups were more willing to "negotiate the stairs after they were painted blue and yellow," because it allowed them to more readily distinguish where each step begins and ends.
Sensing the Supernatural?
As established, the differences in dogs' eyes allow them to routinely see and detect things that humans cannot. And, as any dog owner would attest, our furry friends often appear to bark or growl at seemingly nothing or fixate intently on a particular empty corner of the room, making us feel thoroughly freaked out!
Supernatural aficionados like pet psychics will be quick to tell you that these behaviors are simply a sign of your dog's direct connection with the spirit world.
Though there's no scientific backing to support the idea that our dogs pick up on the presence of spirits unseen to the human eye, we know without a doubt that animals have heightened, superhuman senses. For one, dogs can "detect changes in barometric pressure or electromagnetic fields," often giving them a sixth sense, if you will, about bad weather.
With these superhuman senses in mind, there's usually a plausible explanation for a dog's puzzling behavior, such as a faint sound, distant scent, or approaching storm. Regardless if you're quick to deem your dog's "barking at an empty corner spell" as a sign of a supernatural visitor, it's truly awe-inspiring to consider the enhanced way in which our canine companions experience and engage with the world.
In all, while our pups might not see their surroundings in the full range of colors that we do, their vision is uniquely adapted to their evolutionary needs, and, in many areas, outperforms human vision. Whether it's spotting movement from afar or navigating in the dark, our pups have remarkable sensory awareness.
So, the next time you play fetch with your furry friend, remember they might not be chasing the ball because of its color, but rather how it moves against the backdrop of the world they see. And, the next time you're picking out a new toy, blanket, bed, or other fun goodies for your dog, make sure to keep in mind their blue-yellow color spectrum.
Finally, drop a comment below if your dog's behavior ever left you pondering the existence of ghosts. Debunked or not, we'd love to hear about it!