Why do dogs have whiskers?
Your dog’s wiry whiskers definitely add to their cute appeal and enhance their expressive faces. And unlike a cat’s neat rows of neatly-arcing whiskers, a dog’s whiskers seem to grow haphazardly all over their snout and chin, even in their eyebrows!
You might remember something from science class about whiskers helping animals to sense things around them, but is that the real reason why dogs have whiskers?
Let’s take a look at what a whisker is, and why our four-legged friend’s snouts seem covered in these stiff hairs.
What are whiskers?
Whiskers, also called “vibrissae”, are long, thick, stiff hairs that typically grow on your dog’s snout, chin, and eyebrows. Although some dogs might have a few on their cheeks too.
These hairs are much longer and thicker than the rest of your dog’s fur but grow out of hair follicles just like any other hair on their body.
However, whiskers grow much deeper in their skin as the root of a whisker is about three times longer than the roots of their fur. As well as the root of each whisker being very deep, they’re also connected to lots of touch-sensitive nerves. In fact, a dog’s whiskers are even more sensitive than your fingertips!
Lots of mammals have whiskers, including cats and dogs, and once upon a time, even humans! These hairs are important for helping animals to navigate the world around them. Dogs of all breeds will have whiskers, although how they look and how they’re arranged on their face will vary slightly depending on their breed. Even puppies are born with their own little whiskers!
Why do dogs have whiskers?
Dogs have whiskers because these thick hairs are specially adapted to help your dog navigate the world around them by providing an extra sense, and they help to support your dog’s eyesight and improve their spatial awareness.
Your dog’s whiskers are like little radar detectors that can feel tiny vibrations caused by changes in the air current. These changes in air current are triggered by air bouncing off of nearby objects or movement. The whisker can detect these minute changes in the air and communicate that information to your dog’s brain, where the information is put together with other senses, like their sight, to get a better understanding of the world around them.
Your dog’s vision isn’t great, especially close-up. Dogs are great at seeing far-away objects, which is why your pooch always seems to spot that cat down the other end of the street. However, they always seem to miss what’s right under their nose. This is because a dog’s near-sighted vision is incredibly blurred. Plus, most dogs have a significant blind spot caused by their snout!
So their whiskers help them to give them a better understanding of what’s nearby, detecting objects around them and how close they are. That means even in the dark, your pup can find their bowl or favourite ball.
Your pooch can also use their whickers to judge space and if they can safely squeeze themselves in without getting stuck. Their whiskers grow long enough to stick out as wide as your dog’s head is, or sometimes as wide as their body. So if your dog’s whiskers can pass through a gap without being bent, your pup knows the rest of their body can fit too.
As well as helping your dog to “see” what’s around them, whiskers are also used in your canine’s communication. Just like how your dog’s ears and tail will move around according to their mood and give off certain body language, their whiskers can too. For example, an angry dog’s whiskers will bend forwards and flare out.
How do whiskers work?
So how does this super power sense work? Well, while your dog is walking around they stir up the air around them, and as this air moves and bounces off of nearby objects, their whiskers sense the tiny changes in current and determine not only that something is nearby, but how big it is, what shape it is, and whether or not it’s moving.
If it helps to visualise how this works, think of how a bat uses echolocation. They squeak out sound waves which travel around them and bounce back off anything in their path.
The bat’s powerful ears hear the echoes bouncing back off objects or structures in their way, and based on the echoes they can tell big the object is, how far away it is, and how fast it’s moving. Instead of using sound, your dog can simply sense the way the air moves around them and feels it in their whiskers as it bounces back off of things.
That’s why your dog’s whiskers are so important, because when they can’t see close-up things very well, they can’t judge distance or might even lose sight of something entirely in the blindspot caused by their muzzle.
We’ve probably all seen our dog miss a treat we’ve thrown at them, only to end up looking around frantically on the floor whilst we can clearly see it’s right by their feet. They have a tendency to miss what’s right under their nose, so their whiskers help them to “see” what’s there.
They’re also very useful in the dark. When you have the lights out you probably keep your arms out and use your hands to make sure you don’t bump into anything. A dog’s whiskers act in the same way, reaching out and feeling what’s around to stop your dog from bumping into anything.
How many whiskers do dogs have?
I’m not sure if anyone has counted! Some dog whiskers can be hard to see amongst their other fur, especially if you’ve got a long-haired dog. Unlike cats that always have 12 whiskers on each side of their snout in 4 neat little rows, a dog’s whiskers can vary between individuals and breeds.
The rough estimate is that they can have up to 40 on their muzzle, with 20 on each side of their nose. They can also have several on their cheeks and in their eyebrows, and a few more on their chin. There’s no definitive answer though!
Should I trim my dog’s whiskers?
No, you shouldn’t trim your dog’s whiskers. Some owners will mistakenly trim a dog’s whiskers thinking they are unruly hairs, or even because they don’t like the look of them. However, by trimming your dog’s whiskers, you’re depriving them of a very important sense!
Trimming whiskers won’t hurt your pooch, because although these hairs are super sensitive, there are no nerves in the whisker itself so they can’t “feel” them being cut.
However, plucking these hairs out would be extremely painful for your pooch because these hairs are deeply embedded in their skin, and rooted in a mass of touch-sensitive nerves. (Think about how much it hurts pulling hair out your nose, then multiply it!)
Dogs without whiskers can often seem uncertain, especially when moving around in the dark. They’re also more likely to walk into objects or lose sight of things right under their noses. Without whiskers, your pup’s spatial awareness will be reduced and their sense of touch won’t be there to support their eyesight.
Do dog whiskers grow back?
Yes, a dog’s whiskers will eventually grow back if they lose one or have it snipped off somehow. In fact, your dog will actually shed or moult their whiskers just like any other hair in their body.
However, it takes a long time for these whiskers to grow back to their original length, and it can take at least 16 weeks for your dog’s missing whiskers to grow back and reach their full length again. That’s a long time to go without their sense of touch for!
Do dogs get whisker fatigue?
Whisker fatigue is more often associated with cats than our pups, but do dogs get whisker fatigue too and what is it?
In cats, whisker fatigue is a condition caused by overstimulation of the whiskers, which can put your feline friend into sensory overload and stress them out. There’s debate amongst vets about whether or not it is a real condition, and how much of an issue it really is.
As for dogs, there doesn’t seem to be any sign that whisker fatigue affects them. Cat’s have much more sensitive whiskers though, which would explain why whisker fatigue affects them but not our canine companions.
- Why Don't Humans Have Whiskers? Mcgill, Office for Science and Society, July 2017