Can Dogs See in the Dark? All About Dogs and Night Vision
The structure of the eye plays a big part in how well dogs see at night.
Dog owners know that dogs are the best companions to have when out for a walk, on a hike, or simply relaxing on the couch. They also know that their furry buddies can be mysterious. Common canine puzzlers include deciphering dog behavior, understanding a dog’s facial expressions, figuring out the answer to the eternal question “Why does my dog stare at me?” and wondering “Can dogs see color?” And it doesn’t end there. For instance, when out for an evening stroll, have you ever wondered “Can dogs see in the dark?” Read on to solve that mystery once and for all.
Do dogs have night vision?
It depends how you define night. You’ll never find your pug prancing around the pitch-black house at 3 a.m. as if he had tiny night-vision goggles on. Dogs can’t see any better in total darkness than we can.
So can dogs see in the dark or not? In semi-darkness, like in the dim light of dawn and dusk, for sure. They have us beat, in fact. Dogs are much more able to spot shapes and motion, even at a distance, in semi-darkness than people are.
How do dogs see in the dark?
Your dog has her retina (the nerve layer that lines the back of the eye, senses light, and creates impulses that travel through the optic nerve to the brain) to thank for that. “The retina has light-sensitive cells, called rods, which help dogs and humans to see in low light,” Katy Nelson, DVM, senior veterinarian at Chewy, tells Reader’s Digest. “While we’re not sure of an exact number, research has shown that dogs have many more of these rods than we do.”
How well can dogs see in the dark?
As it turns out, those big, sweet “puppy eyes” serve a purpose beyond cuteness. “The canine eye, like the eyes of cats and other mammals, has a larger pupil than a human eye, allowing more light into the eye,” explains Dr. Nelson. Plus, dogs have a wider field of vision than we do, owing to the fact the eyes of most breeds are spaced farther apart than ours. “A dog’s field of vision is approximately 250 degrees, as compared with that of a human, at around 190 degrees,” says Dr. Nelson.
But if it makes you feel any better, humans have keener vision in broad daylight. “The other type of cells in the retina are called cones. Cones perceive color and function best in well-lit environments,” Dr. Nelson adds. “While the human eye has six million cones, dog eyes have only about 1.2 million. This means that dogs have less acute vision in bright light than we have.” So we can definitely spot those kites and seagulls at the beach better than our dog can. But when it comes back to what dogs can see at night, we can’t compete.
Is it OK for dogs to be in the dark?
For short periods of time, yes. If you’re going to be out for the evening, leaving a light on can make your home seem more “normal” in your absence, and it may help your dog relax if he’s prone to separation anxiety. But there’s no need to leave every single light in your home on just for your dog. In fact, darkness at the right time can be good for dogs. According to the Sleep Foundation, dogs, like humans, have circadian rhythms that are influenced by light. It’s easier for them to sleep if it’s dark, or at least dim.
Can dogs be scared of the dark? It’s not common. That makes sense when you remember that the answer to our question “Can dogs see in the dark?” is a resounding yes. And when a dog does seem to be afraid of the dark, oftentimes it’s not the dark itself. Rather, he’s associating it with unrelated scary occurrences that have happened in the dark, such as fireworks and thunderstorms.
Why do a dog’s eyes glow green in the dark?
You’ve probably noticed on your evening walks that when the light hits your dog’s eyes a certain way, they appear green. This is due to the tapetum lucidum in the back of the eye. “It acts as a mirror, reflecting the light that enters it and allowing the retina another opportunity to pick it up,” says Dr. Nelson. “It also amplifies the light through fluorescence, slightly changing the color of the light reflected back to a wavelength that is closer to what the rods can detect.” Humans don’t have a tapetum lucidum, which is why dogs are five times more sensitive to light than we are.
Can dogs see color?
The idea that dogs live in a black-and-white world was once widely accepted, but dogs can actually see in color, albeit not to the extent we can. “Different types of cones allow for the detection of different wavelengths of light, and thus, colors,” says Dr. Nelson. “Humans have three different kinds of cones, while dogs have only two. Because of this difference, the number of colors your dog can perceive is fewer than the array humans can.” Their two-cone vision is commonly referred to as having “dichromatic eyes.”
Can dogs be color-blind?
Technically, dogs are color-blind, at least in the human sense. Canine eyes function similarly to those of humans with the most common type of color-blindness: red-green color-blindness. Those folks, along with dogs, cannot distinguish shades of red or green. “Dogs see mainly blues, yellows, and grays,” says Dr. Nelson. “To a dog, an orange or red toy lying in green grass appears the same color as the grass. Dogs can better see a blue toy in green grass.” Now we know why bright yellow tennis balls seem to be universally loved in dogdom.