How Dogs “See” the World

The Power of a Nose

When you head outside with your dog, do you find yourself hurrying them along? Getting frustrated by their need to smell everything? It may seem like they’re lollygagging, but they’re actually using their most powerful sense – their sense of smell.

Dogs “see” the world very differently than we do. Unlike humans who rely heavily on visual information, dogs have an overdeveloped sense of smell that gets added to the mix. In fact, the olfactory bulb in a dog’s brain that processes smell is approximately 30-40 times larger than a human’s. They also have at least 300 million smell receptors in their noses – and even as many as one billion! How many does a human have? Around 5 million.

But that’s not all. Even the anatomy of their nose boosts their sniffing ability.

Each time a dog inhales, the air gets broken into two streams. One goes directly to the lungs and the other heads straight to the olfactory gland for sensory processing immediately. When they exhale, the air passes through the side slits in their noses, creating a swirling flow of air that draws fresh scent molecules back into the nose.
This gives them the ability to detect, analyze, and differentiate between a staggering number of scents – and they can do it with concentrations of fragrances 100 million times less than what a human can detect. Not sure what that means? Think of a spritz of perfume. You might be able to smell the aroma in a small room, but a dog could do it in an enclosed stadium – and they could tell you what’s in it!

Dogs can also detect scents that can’t be seen, like the hormones humans and animals naturally release. This canine superpower enables them to detect our emotional states and even health conditions, like pregnancy, cancer, low blood sugar, and epilepsy.

Because smell plays such a crucial role in how dogs “see” their world, researchers and canine behaviorists recommend giving dogs plenty of time to use their noses. Letting them put this sense to work can help relieve stress, anxiety, and improve their overall quality of life.

Curious to learn more about how dog’s see the world? This short video shows these furry sniffing machines in action.