Many a dog owner has wondered what those long white hairs on a dog’s muzzle accomplish. Like many mammals, canines have whiskers on their faces, the numbers and patterns of which vary based on breed. The whiskers are located on the forehead just above the eyes (which we sometimes call the dog’s “eyebrow”), as well as their chin and upper lip. These hairs are much thicker than those that comprise a dog’s coat, and whiskers are imbedded in the skin nearly three times as deep. The whiskers are highly sensory, filled with nerves and blood cells that allow the hairs to work as sensor antennae sending information to the dog’s brain.
Why dogs have whiskers?
Most people associate dog noses as being their primary source of tracking and hunting, while a cat heavily relies on sight and whiskers. How do whiskers function for a dog? The word “whisker” is actually vibrissa which is a derivative of the word vibrio or “vibrate.” These unusual features are well named since whiskers detect vibrations in the area around them. Though they do not have the same number of whiskers as a cat, dogs certainly depend on their whiskers in a variety of ways.
- Alert signals: Whiskers warn dogs about spatial limitations. They let a dog know if something is too close to his face/mouth/eyes, so he can instinctively pull away and protect those vital features. (Watch how dog responds to you lightly touching one of the whiskers on his face. The eye on the same side will instinctively close to protect itself whenever that whisker is touched.)
- Visual aid: Like cats, canine eyes struggle to focus on shapes and objects if they are too close. Whiskers allow a dog to feel an object moving near his face, even if the object might be out of his range of sight. The movement of whiskers will help him “see” objects before him. If he is fetching an item that is difficult to detect, the whiskers will help him find it. Vibrissae also function as a visual aid in the detection of air movement, which helps the dog sense when a predator is quickly approaching, or if there is an object they need to dodge, all based on how the wind around them moves when they are walking or running. The slightest change of air movement communicates volumes to the dog about where he is and what is about to happen.
- Information transmitters: Scientists have observed the brain activity of dogs, and found that nearly 40% of the motion signals sent to the brain were received via whiskers on the face, near the muzzle where most of the vibrissea can be found. Like the other whiskered mammals such as mice/rats, cats, seals and bears, dogs rely heavily on the messages these vibrissae send.
To trim or not to trim?
Some groomers routinely trim dogs’ whiskers whenever they come in for a treatment; without realizing that these coarse hairs play an important role in canine perception. Even show dog owners or successful breeders will often have the whiskers trimmed so that the dog will have a tidier look about him before the competitions. However, in care for the dog’s ability to navigate well when his eyesight grows dim and to be able to guard his face, it would be advisable not to cut the sensory hairs that equip him to function freely. Whisker snipping is stressful for dogs, since it makes them feel vulnerable, and severely limits their ability to sense their surroundings.