How Good is a Cat's Sense of Smell?

When it comes to exceptional olfactory powers, dogs pretty much have the market cornered. Most people are well aware of dogs' abilities to sniff out even the faintest of smells, from an old crumb that fell behind the couch to things imperceptible to the human eye, like cancer or oncoming seizures. Cats, on the other hand, don't get nearly as much recognition when it comes to their sense of smell. Is that because theirs is that much less impressive than a canine's? And if so, how good are cats with their noses?

White kitten cat smells flower on grass
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Cats and their senses

Humans rely on all five of their senses to navigate the world around them, although some, like the sense of smell, are usually less crucial to their survival than say, sight or touch. Cats, on the other hand, rely on their sense of smell in a way which we will likely never understand or experience thanks to our inferior olfactory receptors (five million compared to their 80 million, according to VCA Hospitals.) This sense can help cats pick up smells ranging from the obvious scents, like rancid meat, to chemical and hormonal ones, like when another cat is in heat and ready to mate, or subtle clues that prey is just around the corner.

In addition to their sense of smell, cats also rely on other things to help them understand what's expected of them, both in the physical sense and in social scenarios. Their sense of sight is helpful for obvious reasons, while their sensitive whiskers assist them in remaining aware of their surroundings even when they can't see so well. Body language, while not technically one of the five senses, plays a huge part in feline communication, both when engaging with other cats and when dealing with their human counterparts. Physical cues, such as ear placement and arched backs, send highly specific messages which are used for a number of reasons, from avoiding fights to asserting their dominance over a particular territory.

Tabby cat nose & whiskers
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How cats smell

In addition to the millions of smell receptors cats come equipped with, there's another "secret weapon" that helps felines take in odors better than we can — the Jacobson's organ. Also known as the vomeronasal organ, the Jacobson's organ is found in the roof of every cat's mouth, according to Ridgewood Vet. This small but mighty organ allows the brain to decode chemicals found within an undetectable scent and identify pheromones, which are used during mating to determine whether a cat is ready to breed. If you ever notice your cat scrunch up his face or open his mouth while he's investigating a smell, what he's doing is opening his mouth wider, which allows the scent to reach the Jacobson's Organ. This behavior is called a Flehmen response, and your cat does this so he can get a better idea of the situation at hand.

Pheromones play a large part in cat communication, and not only when seeking out a potential mate. Scents contained in anal glands and in glands located on a cat's forehead can deliver important information, like whether a cat is friendly, or healthy.

two cats kissing
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How good is a cat's sense of smell?

It's safe to say that cats can definitely out-smell any human being on the planet, but how do they stack up against other notable sniffers? Unlike dogs, there is little scientific research that measures a cat's ability to smell, although some believe that cats do have the potential to smell at least as well, if not better, than canines. A 2016 study suggests that, because the feline sense of smell is so finely tuned, the possibility that it could be as useful as a dog's when sniffing out undetectable scents like diseases, bombs, and bugs is certainly there assuming the time it takes to train cats to accomplish such feats be given to our feline friends.