Most dog owners are fascinated and proud about the number of abilities their extraordinary dogs have. One of the many wonders is can a dog see in the dark? If they can, how well can they see?
No dogs can’t see in complete darkness. However, they can see extremely well in dim lighting. Thanks to their unique eye structure, it makes it possible. Today, domestic dogs continue with this trait from when their ancestors needed it to spot even the slightest movement in low light to track and hunt down prey in the wild.
Now we know that dogs have excellent eyesight in the dark light. Let’s find out how dogs can see so clearly in dim light?
The Eye Structure
The unique structure of its eyes supports your pet dog’s ability to see clearly in the darkness. Just like dogs and other mammals, canine eyes also have larger pupils compared to humans.
The retina of a dog contains a type of light-sensitive cells that are known as rods. These are the cells that help a dog see in low light conditions.
We also have rods; however, dogs have more rod cells in their retina. The retina also contains cone cells which determine the types of colours that dogs can see.
Flicker Fusion Frequency (FFF)
The ability to see in the darkness is also heightened by a factor known as the Flicker Fusion Frequency (FFF). At this frequency, the flickering light does not appear to flicker anymore. Typically, the faster a species moves in an environment, the more its FFF ability is.
The secret weapon that facilitates the dog’s ability to see in the dark is the tapetum lucidum. It acts as a type of mirror inside the eyes of a dog. That means it reflects the light entering the dogs’ eyes, giving the retina another chance to register light.
These three factors combined: the rods, FFF, and tapetum lucidum help dogs see in the dark so much better than us humans.
Can dogs see better than humans?
There is no simple answer to this question. Although with the combination of the many rod calls, the FFF, and tapetum lucidum, in theory, dogs do have better eyesight than humans in specific environments or rather see differently to us. However, one of the limitations a dog has compared to us humans is the vision of colour.
Dogs possess only two types of cone cells that facilitate coloured vision. Compared to that, humans have three different types of cone cells, which help us to distinguish more colours than dogs.
Another feature that gives dogs good all-around vision is the placement of their eyes. Having eyes on the side of their faces gives them a much better visual field compared to us humans. A dog’s field of view is 240 degrees, and a human area of field vision is 200 degrees. That’s a whopping 20% better field view size than humans.
Did you know a rabbit has a field vision of nearly 360 degrees? That’s 80% more vision area covered more than humans and 50% compared to a dogs field of vision. The large field vision is down to the placement of the rabbit eyes.
Why do dogs eyes glow in the dark?
A dog’s eyes glow in the dark thanks to the tapetum lucidum. It acts as a light-reflecting mirror known as eyeshine. It also amplifies the reflected light, a phenomenon that is known as fluorescence.
Compared to the human eyes, the tapetum of dogs reflects about 130 times more light.
Why can’t dogs see in total darkness?
Dogs do not have night vision. That means they cannot see when it is pitch dark or when there is no light. The eyes of your dog are made up of the pupil cornea lens, and retina. In the retina, you can find multiple photoreceptors created using rod cells and cone cells. Rod cells observe light and help to detect motion, while the cone cells observe colours and brightness. Without any light to work with, this is why they can’t see in total darkness.
Can dogs see colour?
Yes, dogs can see in colour. Dogs can see colours similar to a person that is colourblind. The reason can be explained further by the different cone cells that dogs and humans have in their eyes. There are various types of cone cells found in the bodies of humans and other animals. While humans have three different types of cones in their eyes, dogs only have two. That is why dogs cannot recognise the colours red or green colours. The colours that your dog can see are much less than the extensive range of colours, which humans can perceive.
Colour Blindness Explained
Humans can suffer from three different types of colour blindness, so it is only fair to assume that dogs also suffer from the same type of colour blindness. Dog’s eyes function similarly to colour blind humans. As dogs have only two cone cells in their eyes, they can only see blue, yellow, and grey colours. To them, a red or orange toy lying in the lush green grass appears in the same colour. That is why your dog may not respond to a bright red toy as much as you want them to. In such cases, your dog is interested in the toy, but they cannot locate the toy all the time. From that, you can understand why dogs tend to get so excited about yellow-coloured tennis balls or white footballs.