Why Do Dogs Have Whiskers?
By Dr. Carly I.O'Malley December 28, 2020
Dogs are such an important part of our lives and so in tuned with humans that we may sometimes forget that they are an entirely different species that evolved for a different lifestyle than ours. This includes how they navigate and sense the world around them. Our senses help us receive information from the environment and prepare for the appropriate response. Dogs evolved to be active at dawn and dusk, or at night, and therefore have senses that help them navigate their environment in low levels of light (Byosiere et al., 2018). Part of this adaptation is having whiskers. In this article, we will discuss the science behind dog whiskers and how they help your dog sense the world around them.
Why Do Dogs Have Whiskers?
Like humans, dogs have five main senses: sight, sound, smell, taste, and touch. Whiskers are a key element of a dog’s sense of touch. However, some may argue that whiskers could make up a sixth sense, one that humans do not have. Whiskers are important for special navigation, especially in low light environments.
What Are Whiskers?
Whiskers are also known as vibrissae and are found on almost all mammal species. Vibrissae is derived from the Latin word meaning “to vibrate.” Whiskers are a specialized hair with nerve endings that allows the whiskers to take in information from the environment and send that information to the brain (Coren, 2016). Whiskers are sensitive enough to allow animals to “see” their environment in the dark. Whiskers also detect air flow, allowing animals to find objects around them before they physically touch them (Buzhardt, 2015). Whiskers are important for a variety of other functions such as communication between members of the same species, hunting prey animals, defensive behavior, pheromone signaling, and swimming (Ahl, 1986).
Do All Dogs Have Whiskers?
Yes, all dogs have whiskers. They are an important feature for many mammal species. However, there may be breed differences in whiskers based on the breed’s purpose. There is evidence that whisker length is different across species based on the ecology of that animal (McGill, 1980). For example, some breeds were used for hunting in rodent tunnels. These dogs would need to be able to run through small spaces with little to no light. These dogs may need shorter, stronger whiskers than dogs used to herd sheep in open fields during day light. In other species, burrowing animals such as mice have shorter whiskers than hunters like cats (McGill, 1980). Humans are one of the mammal species without whiskers, which means we will never know the sensation of having them and using them to navigate. Other mammals that do not have whiskers include platypus, echidna, and some hairless breeds, like the Sphinx cat.
Where Are Dog Whiskers Located?
Dog whiskers are located on their face: above their eyes, on their upper lips, and on their chin. The whiskers are located in these areas to help dogs with spatial navigation since dogs move forward with their face. These whisker locations are especially helpful when dogs navigate under low light conditions.
Some mammals, like cats and squirrels, have whiskers on the back of their legs. These whiskers help them as they crawl through small spaces or climb up trees. Dogs do not have whiskers on their legs.
What Are Dog Whiskers Made Out Of?
Whiskers are a type of hair. Therefore, whiskers are made of keratin. Keratin is a protein that also makes up hair, nails, and even rhino horns! While whiskers are a hair, they are specialized hairs, meaning they are much thicker than normal fur on the rest of the dog’s body. Whiskers also have blood vessels and nerve endings connected to them. Each whisker has 100-200 nerve endings attached to the follicle and its own blood supply. The structure of whiskers is thought to be the same across species (Rice et al., 1986).
When Do Dogs Start To Grow Whiskers?
Puppies are born with their eyes and ears closed, but they are born with whiskers. Their whiskers help them navigate their environment before their sight and hearing are developed. In rats, whiskers help pups find their way to their mother for nursing, especially their first nursing after they are born (McGill, 1980). This is likely an important part of whiskers on dog pups as well, playing an important role in bonding between a puppy and its mother and littermates (Buzhardt, 2015).
What Is Whisker Sensitivity?
Since whiskers contain nerve endings, they are highly sensitive structures. Some dogs may experience higher levels of sensitivity in their whiskers, leading to discomfort. This may cause anxiety, especially around eating and drinking with certain bowls. If your dog is reluctant to eat out of their bowl, or does strange behaviors around feeding and drinking, you may want to question whether or not your dog is experiencing whisker sensitivity. Some dogs with whisker sensitivity may also become hand shy, where they recoil from someone reaching out to pet them. These dogs may also find head halters uncomfortable. This may lead to aggression if the dog’s discomfort is not addressed (Coren, 2016).
If you suspect your dog has whisker sensitivity, provide your dog wide, shallow bowls to eat and drink out of. Be mindful of where and how you pet your dog. Focus petting mainly on the neck and back, if your dog allows. Encourage strangers to do the same and actively avoid letting people reach for your dog’s head during petting. This is especially important during interactions with children. Children do not always understand safe ways of interacting with dogs. Children should never be allowed to pull at or cut dog whiskers. Another step you can take to keep your dog comfortable is to walk your dog on a back-clip harness. This will help keep the leash away from their face.
Should You Trim Your Dog’s Whiskers?
Due to the number of nerve endings in the whisker, you should not attempt to pluck the whiskers. Whisker trimming is a common grooming practice, especially for show dogs. Dog breeders think having the whiskers trimmed give the dog a cleaner look (McGill, 1980). Whiskers do grow back. But when you think about how sensitive whiskers are and how important they are to dogs, you may want to avoid having your dog’s whiskers trimmed. Doing so may cause some sensitivity or disorientation as your dog learns to re-navigate without them (McGill, 1980; Fernández-Montoya, 2018).
While there is no formal research on the emotional and physical response of whisker trimming in dogs, there is research on other species that suggests whisker trimming should not be a common practice (McHill, 1980; Fernández-Montoya, 2018). Most of the research done on whiskers in mammals has been conducted on laboratory rodents. Studies looking at whisker trimming in rats showed evidence that doing so affects their navigation skills. Rats with trimmed whiskers exhibited changes to locomotor activity and depth perception. Previous research has also shown that whisker trimming in cats reduces their overall activity (McGill, 1980). A more recent study on rats found that trimming whiskers can cause permanent changes to the nerves connected with the whiskers (Fernández-Montoya, 2018).
Do Dog Whiskers Grow Back?
Yes, just like our hair and nails, whiskers do grow back. They naturally grow and shed off like the fur on your dog’s body or like the hairs on our head. It is fairly common for dog parents to find whiskers around the house. There is no reason to be alarmed if you find a whisker. Whiskers will continue to grow back for the life of the dog.
The goal of this article was to help dog parents learn a little more about how their dog navigates the world. Whiskers are an important part of a dog’s senses. They help dogs move through areas of low light and detect changes in the environment. Puppies are born with whiskers. They are their primary source of information for navigation until their eyes and ears open. Whiskers are located on a dog’s face, on the eyebrows, upper lips, and chin. Whiskers have nerve endings, which makes them highly sensitive. Some dogs may experience heightened whisker sensitivity which is exacerbated by food and water bowls, petting, and head halters. But, there are steps you can take to help your dog feel more comfortable.
Ahl, A.S. 1986. The role of vibrissae in behavior: a status review. Veterinary Research Communications 10:245-268.
Buzhardt, L. 2015. Why do dogs have whiskers? Veterinary Centers of America. Retrieved October 25, 2020.
Byosiere, S.-E., Chouinard, P.A., Howell, T.J., and P.C. Bennett. 2018. What do dogs (Canis familiaris) see? A review of vision in dogs and implications for cognition research. Psychonomic Bulletin & Review 25(5):1798-1813.
Coren, S. 2016. Why do dogs have whiskers? American Kennel Club.
Fernández-Montoya, J., Martin, Y.B., Negredo, P., and C. Avendaño. 2018. Changes in the axon terminals of primary afferents from a single vibrissa in the rat trigeminal nuclei after active touch deprivation or exposure to an enrichment environment. Brain Structure and Function 223:47-61.
McGill, T.E. 1980. Amputation of vibrissae in show dogs. International Journal for the Study of Animal Problems 1(6).
Rice, F.L., Mance, A., and B.L. Munder. 1986. A comparative light microscopic analysis of the sensory innervation of the mystacial pad. I. Innervation of vibrissal follicle – sinus complexes. Journal of Comparation Neurology 252(2):154-174.