Back in 2009, Alexandra Horowitz’s first book, Inside of a Dog, made it to the top of every bestseller list. Heralded in this magazine and by others who wanted to learn what it means to be a dog, it delivered on the promise of its subtitle: What Dogs See, Smell and Know. It also introduced many of us to the concept of Umwelt—another’s perception of the world—coined by biologist Jakob von Uexküll.
Imagining what it is to be a dog and to enter a dog’s subjective world was, and still is, an entrancing prospect. What better guide to the “inside of a dog” than a comparative cognitive scientist like Horowitz? She writes in a clear vernacular: accessible, erudite, poetic and downright friendly. No wonder her first book became such a sensation.
And now we have her new book, Being a Dog: Following the Dog into a World of Smell, which not only delves deeper into dogs’ amazing sense of smell, but also considers the human olfactory capacity, even if it is rather paltry compared with that of dogs. Truly understanding another species requires that, as ethologist Frans de Waal has explained, “we need to try to step outside our own narrow Umwelt and apply our imagination to theirs.” That is exactly what Horowitz brings to her books.
Similar to recent books such as Being a Beast by Charles Foster (where the author literally lived underground as a badger), or Thomas Thwaites’ excursion into the Umwelt of goats in GoatMan, in Being a Dog, Horowitz learns to polish her own sense of smell. She undertakes this quest not only to better understand what she might be missing, but also, to get a glimmer of how dogs’ noses help them navigate their world. The book begins with a look at the canine nose, which “is rich in a way we humans once knew about, once acted on, but have since neglected.” Following the lead of her two dogs, she puts her “nose to the places the dog nose goes.”
We all love factoids about dogs, and this book delivers a trove of them: Dogs scratch up the ground after they poop in order to transmit their personal message to other dogs; their paw pads have scent glands and digging spreads their odor, broadcasting their signal far and wide (canine social networking in action).
Wagging tails serve a similar purpose, spreading the scent from their anal sacs. They smell when they dream; watch their nostrils twitch. Dogs rarely mark over their own urine postings. Males like to sniff tail areas first, while females prefer to start with faces.
We learn about the physiognomy of their smelling instrument, from nostrils (nares) to olfactory epithelium and vomeronasal organ, or VNO, and up to the brain’s olfactory bulb. When they sniff, they start with either the right or left nostril, depending on what they’re investigating. Unlike other senses, nostrils are ipsilateral, meaning that an odor entering the right nostril goes to the right side of the brain for processing, and one entering the left goes to the left side.
Horowitz takes us on a grand tour of scent-work professionals, from the Working Dog Center at the University of Pennsylvania to the University of Washington’s scat-detection dogs, with stops along the way to visit other working and detection dogs. At the book’s end, she treats her dog Finnegan to classes in nosework, which quickly become what she calls his “Favorite Place on Earth.” Definitely something in which all our dogs would love to partake.
It seems that for most of us, smelling isn’t something we practice much. One of the most remarkable comparisons she draws is the difference in the endowment of olfactory sensory cells (epithelium) between humans and dogs. As she explains, “If his olfactory epithelium were spread out along the outer surface of the dog’s body, it would completely cover it. In humans, ours would about cover a mole on our left shoulder.”
While we have a long way to go to catch up with our dogs, by the book’s end, the author has us tapping into our puny epithelium, sniffing and snuff ling. We thank Alexandra Horowitz for providing this inspiration.