“Dogs noses are specifically adapted to function much better than ours” explains Dr. Michael T. Nappier, of the Virginia Maryland College of Veterinary Medicine.
And below a few examples of the wonders those little powerful ‘machines’ can accomplish!
𝗙𝗮𝗰𝘁𝘀 𝗔𝗯𝗼𝘂𝘁 𝗬𝗼𝘂𝗿 𝗗𝗼𝗴’𝘀 𝗡𝗼𝘀𝗲
① The human nose contains about 6 million olfactory receptors that allow us to recognise thousands of different smells. It may sound a lot… Until you realise that inside your dog’s nose there are up to 300 million receptors!
And the part of their brain dedicated to interpreting the smells picked up by these powerful noses is about 40 times larger than ours.
② A dog’s sense of smell is between 10,000 and 100,000 times more acute than our own.
Alexandra Horowitz, a dog-cognition researcher at Barnard College, writes: “…while we might notice if our coffee has had a teaspoon of sugar added to it, a dog could detect a teaspoon of sugar in a million gallons of water, or two Olympic-sized pools worth.” – Inside of a Dog.
③ Short-nosed and flat-faced dogs have fewer scent-detecting receptor cells than dogs with longer snouts.
④ When humans inhale, we use the same air passage to both breathe and smell. Dogs’ noses, on the other hand, include a fold of tissue that separates the two functions. Inside a dog’s nose there is a microscopically small, spongy membrane containing the scent cells.
⑤ A moist nose picks up smells better. The mucus helps to sort and recognise smells. This way, the scents are efficiently organized and sent to the brain to be identified. Dogs also lick their noses quite often to clean them, and a wet nose helps cool down their bodies, as well.
⑥ Like the fingerprints of humans, a dog’s nose print may be just as unique. There are companies that register the nose prints and store them in case the pet is lost or stolen, and kennels have begun a similar procedure. Canada has used this procedure to identify dogs for decades.
⑦ Unlike humans, dogs can move each of their nostrils independently from the other. This is why dogs are great at tracking scents, and how they’re able to tell which direction the smell comes from.
⑧ It’s a little gross when your dog sniffs a random dog’s butt. However, there’s some very important communication happening. Sniffin each other, dogs share important information like age, diet, and temperament.
⑨ According to Dr Nappier, a dog’s vomeronasal organ helps them detect pheromones (a chemical substance produced and released into the environment by an animal affecting others of its species).
⑩ A dog’s nose allows them to sense the passage of time. Odours change throughout the day, including their density in the air. Dogs can detect tiny reductions in the concentrations of odour molecules that occur over periods of time. That’s how their “internal clock” can tell when it’s mealtime or when you are about to get back from work.
⑪ Research indicates that a dog’s sense of smell can pick up fear, anxiety, and even sadness or happiness. The flight-or-fight hormone, adrenaline, is undetectable by our noses, but dogs can smell it. Also, fear or anxiety is often accompanied by increased heart rate and blood flow, which sends telltale body chemicals more quickly to the skin surface. Trying to mask your strong feelings will not deceive a dog’s sense of smell!
⑫ Human bodies shed microscopic particles (referred to as raft particles) at a rate of 40,000 per minute. Part of them will fall on the ground and will remain there for a while, and about 50% will float in the air. Dogs’ olfactory abilities can detect the scent of these tiny particles. Trained noses can track a scent by following the highest concentration of ground particles, or through air scenting. An interesting fact: a trained search dog can detect just 3 particles of human scent per trillion particles of air!
⑬ Dogs have the ability to sniff out diseases in humans, particularly cancers. Malignant tumours release minuscule amounts of chemical compounds that do not exist in healthy tissue. Trained dogs are able to detect those changes long before they show up in a blood test. A study published in Integrative Cancer Therapies related how five trained domestic dogs were able to accurately identify lung cancer in 99% of patients and 88% of people with breast cancer by merely sniffing the patients’ breath. Additionally, a British study discovered that dogs are efficient in detecting sudden blood sugar drops in people with Type 1 diabetes. The research results noted that 65% of dogs warned their diabetic ‘parents’ of an imminent attack by whining and barking.
⑭ Scientists at the Max Planck Institute for the Science of Human History and the department for general psychology and cognitive neuroscience at Friedrich Schiller University of Jena in Germany have recently published a study providing evidence that dogs create mental pictures of what they’re searching for when they track a scent trail. In other words, dogs expect to find a certain thing when they pick up a certain scent.
⑮ Last but not least… A new sense was discovered in dogs’ noses: the ability to detect heat. “Dogs are able to sense the thermal radiation coming from warm bodies or weak thermal radiation and they can also direct their behaviour according to this signal,” said Anna Balint, lead author of the study.
The ability to sense weak, radiating heat is known in only a handful of animals: black fire beetles, certain snakes, and one species of mammal, the common vampire bat, all of which use it to hunt prey.
Next time someone would like to say “it’s just a dog” – he may want to rethink that.
 Oxytocin and Cortisol Levels in Dog Owners and Their Dogs Are Associated with Behavioral Patterns
 The science of sniffs: disease smelling dogs
 Odour representation and search behaviour in domestic dogs (Canis familiaris) of different education
 Dogs can detect heat with an ‘infrared sensor’ in their nose, research finds