Dogs’ sense of smell is extraordinary, but why?
Dogs know and recognize the world and acquire essential information about other dogs through its sense of smell. They live in a world of smells. While humans primarily depend on their vision, dogs use smell to assess their surroundings and communicate.
Dogs can get a lot of information when they go for a walk, for example. Letting it lead the way and take as much time to smell as it would like is a great idea so as to allow them know the world around them. We should do the same thing when we meet another dog, and they both explore their respective anogenital areas with their noses.
It is not “wasting” time, but reading both a geographical map of the place (what is there, who is there, who has been there, who has been there) and other dogs‘ identity cards.
Dog’s Sense of Smell: Jacobson’s organ
You’ve probably noticed that when you get home, your four-legged friend takes some time to sniff you. What it is doing is actually looking for answers in its own way to questions like the following ones: Where have we been? How are we? And the most important question: Who have we been with? Your pet will know immediately if you were with another dog. “Betraying” a dog without being discovered is an impossible mission!
Crowded places as well as veterinary clinics are like a concert of information for our dogs. They perceive smells of both dogs that are present and those who have passed by. While for us, a veterinary clinic is just a place where there are dogs, owners, and doctors.
Dogs’ sense of smell is so extraordinary that when we only see a white dog, whether big or small, our dog can determine a new friend’s age, gender, sexual availability, if it is healthy or ill, if it is anxious, fearful or aggressive, if it has strong character or if its submissive by simply smelling.
Just like cats, dogs have a vomeronasal organ, called Jacobson’s organ, which allows them to perceive pheromones, chemical substances produced by certain types of glands. Pheromones are the ones that provide them with all the useful and necessary details about other dogs, that is, essential information for their social life.
Dog’s Sense of Smell vs Humans
Numbers will help us to understand how powerful a dog’s sense of smell is compared to ours:
- Dogs have between 18 and 150 square centimeters of the olfactory epithelium, a specialized tissue that lines the nasal cavity.
- Humans have around 2,5 to 4 square centimeters of it.
The amount of olfactory receptors vary according to the dog breed. For example, Labrador Retrievers possess up to 220 million olfactory receptors in their noses! German Shepherds have up to 200 million of them, Fox Terriers have 147 million of them, Dachshunds have 125 million of them, and Bulldogs have 100 million olfactory receptors. What about humans? Humans only possess up to 5 million olfactory receptors.
You have probably been impressed with your dog’s incredible sense of smell. However, its olfactory capabilities decrease according to three variables:
- Skull type is a key factor in determining dogs’ sense of smell. Brachycephalic breeds, that means short-nosed dogs, have relatively short muzzles and noses and, because of this, the time duration of the air passage is short.
- Another factor that determines whether the sense of smell is strong is the olfactory mucosa’s extent and, consequently, the number of olfactory receptors.
- Genetic selection is the third factor.
A dog’s scenting skills can be developed, refined, and even specialized in searching for certain substances through specific and appropriate training.
The Labrador Retriever is currently the most popular dog used to search for explosive devices, drugs, and people buried under rubble. Why? The answer is simple: The Labrador has the largest number of olfactory receptors of all dog breeds, and it can recognize 500,000 odors, compared to humans, who can only distinguish 4,000.
It may be difficult for us to imagine the world in which a dog lives as it is different from ours in many ways. We see things it does not see, but it senses things we do not hear. While our eyes cannot see what is hidden or what is “gone,” its sense of smell can.
If in doubt, consult a professional who will give you good assistance and answer all your questions.