Inside of a Dog_ What Dogs See, Smell, and Know - Alexandra Horowitz [102]
… It is full of details …
Part of normal human development is the refinement of sensory sensitivity: specifically, learning to notice less than we are able to. The world is awash in details of color, form, space, sound, texture, smell, but we can't function if we perceive everything at once. So our sensory systems, concerned for our survival, organize to heighten attention to those things that are essential to our existence. The rest of the details are trifles to us, smoothed over, or missed altogether.
But the world still holds those details. The dog senses the world at a different granularity. The dog's sensory ability is sufficiently different to allow him to attend to the parts of the visual world we gloss over; to the elements of a scent we cannot detect; to sounds we have dismissed as irrelevant. Neither does he see or hear everything, but what he notices includes what we do not. With less ability to see a wide range of colors, for instance, dogs have a much greater sensitivity to contrasts in brightness. We might observe this in their reluctance to step into a reflective pool of water, in a fear of entering a dark room.* Their sensitivity to motion alerts them to the deflating balloon wafting gently curbside. Without speech, they are more attuned to the prosody in our sentences, to tension in our voice, to the exuberance of an exclamation point and the vehemence of capital letters. They are alert to sudden contrasts in speaking: a yell, a single word, even a protracted silence.
As with us, the dog's sensory system is attuned to novelty. Our attention focuses on a new odor, a novel sound; dogs, with a wider range of things they smell and hear, can seem to be constantly at attention. The wide-eyed look of a dog trotting down the street is that of someone being bombarded with the new. And, unlike most of us, they are not immediately habituated to the sounds of human culture. As a result, a city can be a explosion of small details writ large in the dog's mind: a cacophony of the everyday that we have learned to ignore. We know what a car door slamming sounds like, and unless listening for just that sound, city dwellers tend to not even hear the symphony of slams playing on the street. For a dog, though, it may be a new sound each time it happens—and one that sometimes, even more interestingly, is followed by a person arriving on the scene.
They pay attention to the slivers of time between our blinks, the complement of what we see. Sometimes these are not invisible things but simply those we would prefer they not pay attention to, like our groins, or the favored squeaking toy we stuff in a pocket, or the forlorn, limping man on the street. We could see those things, too, but we look away. Human habits that we ignore—tapping our fingers, cracking our ankles, coughing politely, shifting our weight—dogs notice. A shuffle in a seat—it may foretell rising! A scootch forward in the chair—surely something is happening! Scratching an itch, shaking your head: the mundane is electric—an unknown signal and a whiff of shampoo. These gestures are not part of a cultural world for dogs as they are for us. Details become more meaningful when they are not swallowed up in the concerns of the everyday.
That very attention that dogs bring to us may cause them to acclimate to these sounds over time, to be inculcated in the human culture. Watch a bookstore dog, who lives out the hours of his day surrounded by people: he has become inured to strangers coming by, standing close while they riffle the pages of a book; to being scratched on the head, to passing smells and ever-present footsteps. Crack your knuckles a dozen times a day and a nearby dog will learn to ignore this habit. By contrast, a dog unaccustomed to human habits is alarmed at every one: the most exciting and frightening thing that could happen to a dog left chained to guard a house is that it actually requires his guarding. Guard dogs may only occasionally see an unknown person walking by, a new smell on the air or new sound, let