No matter how quietly I screw off the cap on a jar of peanut butter, within seconds of its opening, I will feel my dog’s dark brown eyes drilling into me. I’m here, those eyes say. And I’m waiting. Waiting, that is, for a spoonful of her favorite treat.
If dogs can sniff out bombs and bedbugs, cancer and orca poop (more on that in a moment), I shouldn’t be surprised that Galen can sniff out peanut butter. And now, having just completed Alexandra Horowitz’s newest exploration of doghood, Being a Dog: Following the Dog into a World of Smell, my appreciation for a dog’s olfactory skills has grown tenfold.
Horowitz, a cognitive scientist who runs the Dog Cognition Lab at Barnard College and the author of Inside a Dog: What Dogs See, Smell, and Know, is an exceptional guide into the science of smell as it pertains to both dogs and humans. Inspired by her work at the lab and her own rescue dogs, Finnegan and Upton, Horowitz explores not just the physiology of the canine and human olfactory systems, but how both species use their noses to experience the world. As an explorer, Horowitz is a skilled investigator; as a writer her prose is clear and often poetic.
“Have you toured the dog nose?” she asks. “Ridden on a corkscrew of air into the dark vault, bumped along its curves, caught a breeze up to the chamber where a molecule will settle into the wetlands and begin to tickle the nerves to the brain?
I have—at least near enough for my liking.”
As anyone who has walked a dog knows, most dogs prefer the casual, lots-of-time-to-sniff stroll over the fast-paced, this-is-about-exercise hustle. That’s because dogs understand the world through smell, not sight, as we, humans, do. This, of course, has everything to do with biology. “Architecturally,” Horowitz explains, “our noses are children’s block towers next to dogs’ modern architecture: made of similar stuff but in a much simpler, more brutalist formulation.”
For scientifically minded readers, the anatomical design of both species’ noses is deconstructed in detail, yielding takeaways such as the fact that dogs’ nostrils, unlike ours, work independently and ipsilaterally (odors entering the right nostril are processed by the right side of the brain; odors entering the left nostril are processed on the left) and dogs have two-hundred million to one billion olfactory receptor cells—millions more than the six million we have. What this means in practical terms, Horowitz writes, is this:
… let’s think of an aroma pleasing to our noses: cinnamon rolls cooking in a home kitchen. The average cinnamon roll has about a gram of cinnamon in it. Sure, the human nose is on it, from the moment we open the door of the house. Now imagine the smell of one trillion cinnamon rolls. That’s what the dog coming in with us smells when we enter.
It’s because of their remarkable sense of smell that dogs are being trained to sniff out explosives, drugs, malignant tumors, diabetes, truffles, mangoes—the list goes on and on, and even includes that orca poop I mentioned earlier. To discover how such specialized training is accomplished, Horowitz crisscrosses the country visiting the Working Dog Center at the University of Pennsylvania, the Conservation Canines program at the University of Washington, and several scent-research sites in between. It’s in Seattle that she learns about Tucker, the black Labrador retriever mix who detects the “slimy scat”—or poop—left by the orcas who live in Puget Sound. That scat, like the scat of all animals, provides researchers with a gold mine of information, from the health, sex, and reproductive status of an individual animal to how large the population is and how widely it ranges. Scat-detecting dogs, as they’re called, can be trained to track up to twenty species. But what’s perhaps most amazing is that when tracking one species, the dogs ignore what Horowitz calls “the universe of nontarget scat around them.”
Horowitz infuses Being a Dog with her belief that dogs have a lot to teach us about smell. That’s because over millennia, she says, humans “unlearned how to smell.” The good news—for those interested in reversing this trend—is that we can train ourselves to reclaim our sniff. Horowitz has begun to reclaim hers by, among other things, getting down on all-fours and smelling her New York City neighborhood as her dogs do. Fortunately for readers, that’s not her only suggestion. But the meaning behind it couldn’t be any more clear:
“The world abounds with aromas,” says Horowitz, “but we are spectacle-less. The dog can serve as our spectacles.”