This is Scientific American's 60 Second Science.

I'm Christopher Intagiyata.

Old Yeller was a great smeller, and dogs in general have superior smelling abilities.

They detect dead bodies, illegal drugs, and explosives, even cancer.

But dogs don't just have great olfactory gear.

Another reason they're amazing chemical detectors is the sniff.

And it turns out that almost every breed of dog does this at about 5 hurts, 5 times a second.

Matthew Stameats, a mechanical engineer and fluid dynamicist at the National Institute of Standards and Technology.

Sniffing, he says, is really a two-part process.

Inspiration, expiration, right? Inhale, exhale, exhale, inhale, exhale.

That second part, the exhale is key.

So when the dog is actively sampling or sniffing on the ground,

there is a turbulent air jet that exits each nostril during the exhale phase just like when you and I

exhale there's an air jet that comes out of our nostrils right but the dog is kind of

down on the ground and those air jets are vector down and towards its rear and in the

world of fluid dynamics if I pulse an air jet in one direction I basically pull air with it.

So the dog's actually creating a pressure differential

that effectively pulls new sense towards its nose.

Stamates and his colleagues discovered that effect using a 3D printed model of a Labrador Retriever's nose,

which they tested with fluid dynamics equipment. They then outfitted a commercial vapor detector

with sniffing nostrils, inspired by the dog nose.

And they found that the actively sniffing detector was 16 times better at picking up the scent of explosives

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