Ever wonder why a dog’s nose is always wet? Dogs’ noses secrete a thin layer of mucous that helps them absorb scent. By licking their noses, they are able to sample the scent through their mouth.
The vomeronasal organ (also know as Jacobson’s organ) is what gives dogs their superior olfactory skill. Jacobson's organ, which humans do not possess, is located in the bottom of a dog's nasal passage; it picks up pheromones, the chemicals unique to each animal species that advertise mating readiness and other sex-related details.
That’s how much more acute a dog’s sense of smell is than humans.
6 vs. 300 million
Number of olfactory receptors in a person’s nose versus the maximum found in dogs.
How it Works
When dogs inhale, the airflow enters the nose and splits into two different flow paths, one for olfaction and one for respiration (by contrast, humans smell and breathe through the same airways within the nose.)
Dogs can wiggle their nostrils independently. This helps them determine which nostril an odor has arrived in, which is helpful in tracking down the source of a particular scent. All dog owners know that moment when your dog is weaving back and forth trying to pinpoint that smell.
18,000 to 20,000 liters of air pass through an adult’s nose each day.
The two human nostrils are divided by the nasal septum, which is made up mostly of cartilage, a tissue that is stiffer than muscle but more flexible than bone.
The short hairs in the nasal cavity remove dust and other particles. While you can still smell if your nose is cut off, you lose that filtering ability, which makes it difficult to breathe.
The floor of the nasal cavity is also the roof of the mouth.
Did You Know?
Anosmia: The inability to smell.
Dysosmia: When things don’t smell as they should.
Hyperosmia: Having a very strong sense of smell.
It is traditional for Maori people in New Zealand to press noses (hongi) as a greeting.
“Thumbing your nose”—putting your thumb on your nose and wiggling the fingers while sticking your tongue out—is a derisive gesture that first appeared in about 1903.