By Aly Semigran
On the surface, your dog’s nose may look wet, wriggling, and cute. But your pup’s nose is actually a powerful device that guides him through his days in pretty impressive ways.
“Dogs noses are specifically adapted to function much better than ours,” explains Michael T. Nappier, DVM, DABVP, of the Virginia Maryland College of Veterinary Medicine. “They have up to 300 million olfactory receptors in their noses, versus only about 6 million for us. And the part of their brain dedicated to interpreting these is about 40 times larger than ours.”
Here are six interesting facts about your dog’s sense of smell that prove canines have superior sniffers.
A dog’s nose has two functions—one for smell and one for respiration. According to Nappier, a canine’s nose has the ability to separate air. A portion goes directly to the olfactory sensing area (which distinguishes scents), while the other portion is dedicated to breathing.
Dog’s also have the ability to take in and breathe out air at the same time. “When sniffing, dogs noses are designed so that air can move in and out at the same time creating a continuous circulation of air, unlike humans who have to either breathe in or out only,” says Nappier.
Dog’s have a special scent-detecting organ that humans don’t have. This is called the vomeronasal organ, says Nappier, and it helps canines detect pheromones, chemicals released by animals that affect other members of the same species. This organ plays an important role in reproduction and other aspects of canine physiology and behavior.
Dogs smell in 3-D. Dogs can smell separately with each nostril. Just as our eyes compile two slightly different views of the world, and our brain combines them to form a 3-D picture, a dog’s brain uses the different odor profiles from each nostril to determine exactly where smelly objects are in the environment.
A dog’s nose has evolved to help them survive. According to David C. Dorman, professor of toxicology at North Carolina State College of Veterinary Medicine, dogs have used their noses to assist with major life events since the beginning of time. “Evolutionarily, a dog’s sense of smell helps them find a mate, offspring, food, and avoid predators,” he says.
Dogs can smell up to 100,000 times better than a human. Nappier puts this tidbit into perspective with an awe-inspiring analogy. “A dog's sense of smell is its most powerful sense,” he says. “It is so sensitive that [dogs can] detect the equivalent of a 1/2 a teaspoon of sugar in an Olympic-sized swimming pool.”
Which Dogs Have the Best Sense of Smell?
While all dogs have strong sniffers, Nappier says “hound breed dogs have the best sense of smell.” Dorman points out that sturdy working dogs like German Shepherds and Labradors also rank high in their smelling abilities.
Some dogs, like Pugs who have short faces (also known as brachycephalic dogs), may “have some airway compromise that could affect their sense of smell,” explains Nappier.