Inside of a Dog: What Dogs See, Smell, and Know (4 page)

The point of this tale of the tick is that the tick's self-world is different than ours in unimagined ways: what it senses or wants; what its goals are. To the tick, the complexity of persons is reduced to two stimuli: smell and warmth—and it is very intent on those two things. If we want to understand the life of any animal, we need to know what things are meaningful to it. The first way to discover this is to determine what the animal can perceive: what it can see, hear, smell, or otherwise sense. Only objects that are perceived can have meaning to the animal; the rest are not even noticed, or all look the same. The wind that whisks through the grasses? Irrelevant to the tick. The sounds of a childhood birthday party? Doesn't appear on its radar. The delicious cake crumbs on the ground? Leave the tick cold.

Second, how does the animal act on the world? The tick mates, waits, drops, and feeds. So the objects of the universe, for the tick, are divided into ticks and non-ticks; things one can or cannot wait upon; surfaces one might or might not drop onto; and substances one may or may not want to feed on.

Thus, these two components—perception and action—largely define and circumscribe the world for every living thing. All animals have their own
umwelten
—their own subjective realities, what von Uexküll thought of as "soap bubbles" with them forever caught in the middle. We humans are enclosed in our own soap bubbles, too. In each of our self-worlds, for instance, we are very attentive to where other people are and what they are doing or saying. (By contrast, imagine the tick's indifference to even our most moving monologues.) We see in the visual range of light, we hear audible noises, and we smell strong odors placed in front of our noses. On top of that each individual creates his own personal umwelt, full of objects with special meaning to him. You can most clearly see this last fact by letting yourself be led through an unknown city by a native. He will steer you along a path obvious to him, but invisible to you. But the two of you share some things: neither of you is likely to stop and listen to the ultrasonic cry of a nearby bat; neither of you smells what the man passing you had for dinner last night (unless it involved a lot of garlic). We, the ticks, and every other animal dovetail into our environment: we are bombarded with stimuli, but only a very few are meaningful to us.

The same object, then, will be seen (or, better,
sensed
—some animals do not see well or at all) by different animals differently. A rose is a rose is a rose. Or is it? To a human a rose is a certain kind of flower, a gift between lovers, and a thing of beauty. To the beetle, a rose is perhaps an entire territory, with places to hide (on the underside of a leaf, invisible to aerial predators), hunt (in the head of the flower where ant nymphs grow), and lay eggs (in the joint of the leaf and stem). To the elephant, it is a thorn barely detectable underfoot.

And to the dog, what is a rose? As we'll see, this depends upon the construction of the dog, both in body and brain. As it turns out, to the dog, a rose is neither a thing of beauty nor a world unto itself. A rose is undistinguished from the rest of the plant matter surrounding it—unless it has been urinated upon by another dog, stepped on by another animal, or handled by the dog's owner. Then it gains vivid interest, and becomes far more significant to the dog than even the well-presented rose is to us.

Discerning the salient elements in an animal's world—his umwelt—is, in a sense, becoming an expert on the animal: whether a tick, a dog, or a human being. And it will be our tool for resolving the tension between what we think we know about dogs, and what they are actually doing. Yet without anthropomorphisms we would seem to have little vocabulary with which to describe their perceived experience.

Understanding a dog's perspective—through understanding his abilities, experience, and communication—provides that vocabulary. But we can't translate it simply through an introspection that brings our own umwelt along. Most of us are not excellent smellers; to imagine being a smeller, we have to do more than just think on it. That kind of introspective exercise only works when paired with an understanding of how profound the difference in umwelt is between us and another animal.

We can glimpse this by "acting into" the umwelt of another animal, trying to embody the animal—mindful of the constraints our sensory system places on our ability to truly do so. Spending an afternoon at the height of a dog is surprising. Smelling (even with our impoverished schnozes) every object we come across in a day closely and deeply yields a new dimension on otherwise familiar things. As you read this, try attending to all the sounds in the room you are in now that you have become accustomed to and usually tune out. With attention I suddenly hear the fan behind me, a beeping truck heading in reverse, the murmurations of a crowd of voices entering the building downstairs; someone adjusts their body in a wooden chair, my heart beats, I swallow, a page is turned. Were my hearing keener, I might notice the scratch of pen on paper across the room; the sound of a plant stretching in growth; the ultrasonic cries of the population of insects always underfoot. Might these noises be in the foreground in another animal's sensory universe?

Here we begin to see how the dog and the human overlap in our worldviews, and how we differ. A good many objects in the world have an eating tone to the dog—probably many more than we see as such. Feces just aren't menu items for us; dogs disagree. Dogs may have tones that we don't have at all—
rolling tones,
say: things that one might merrily roll in. Unless we are particularly playful or young, our list of rolling-tone objects is small to nil. And plenty of ordinary objects that have very specific meanings to us—forks, knives, hammers, pushpins, fans, clocks, on and on—have little or no meaning to dogs. To a dog, a hammer doesn't exist. A dog doesn't act with or on a hammer, so it has no significance to a dog. At least, not unless it overlaps with some other, meaningful object: it is wielded by a loved person; it is urinated on by the cute dog down the street; its dense wooden handle can be chewed like a stick.

A clash of umwelts occurs when dog meets human, and it tends to result in people misunderstanding what their dog is doing. They aren't seeing the world from the dog's perspective: the way he sees it. For instance, dog owners commonly insist, in grave tones, that a dog is never to lie on the bed. To drum in the seriousness of this dictum, this owner may go out and purchase what a pillow manufacturer has decided to label a "dog bed," and place it on the floor. The dog will be encouraged to come and lie on this special bed, the non-forbidden bed. The dog typically will do so, reluctantly. And thus one might feel satisfied: another dog-human interaction successful!

But is it so? Many days I returned home to find a warm, rumpled pile of sheets on my bed where either the wagging dog who greeted me at the door, or some unseen sleepy intruder, recently lay. We have no trouble seeing the meaning of the beds to the human: the very names of the objects make the situation clear. The big bed is for people; the dog bed is for dogs. Human beds represent relaxation, may be expensively outfitted with specially chosen sheets, and display all manner of fluffed pillows; the dog bed is a place we would never think to sit, is (relatively) inexpensive, and is more likely to be adorned with chew toys than with pillows. What about to the dog? Initially, there's not much difference between the beds—except, perhaps, that our bed is infinitely more desirable. Our beds smell like us, while the dog bed smells like whatever material the dog bed manufacturer had lying around (or, worse, cedar chips—overwhelming perfume to a dog but pleasant to us). And our beds are where
we
are: where we spend idle time, maybe shedding crumbs and clothes. The dog's preference? Indisputably our bed. The dog does not know all the things about the bed that make it such a glaringly different object to us. He may, indeed, come to learn that there is something different about the bed—by getting repeatedly scolded for lying on it. Even then, what the dog knows is less "human bed" versus "dog bed" but "thing one gets yelled at for being on" versus "thing one does not get yelled at for being on."

In the dog umwelt beds have no special functional tone. Dogs sleep and rest where they can, not on objects designated by people for those purposes. There may be a functional tone for places to sleep: dogs prefer places that allow them to lie down fully, where the temperature is desirable, where there are other members of their troop or family around, and where they are safe. Any flattish surface in your home satisfies these conditions. Make one fit these criteria, and your dog will probably find it just as desirable as your big, comfy human bed.

To bolster our claims about the experience or mind of a dog, we will learn how to ask the dog if we're right. The trouble, of course, with asking a dog if he is happy or depressed is not that the question makes no sense. It's that we are very poor at understanding his response. We're made terribly lazy by language. I might guess at the reasons behind my friend's recalcitrant, standoffish behavior for weeks, forming elaborate, psychologically complex descriptions of what her actions indicate about what she thinks I meant on some fraught occasion. But my best strategy by leaps is to simply ask her. She'll tell me. Dogs, on the other hand, never answer in the way we'd hope: by replying in sentences, well punctuated and with italicized emphases. Still, if we look, they have plainly answered.

For instance, is a dog who watches you with a sigh as you prepare to leave for work depressed? Are dogs left at home all day pessimistic? Bored? Or just exhaling idly, preparing for a nap?

Looking at behavior to learn about an animal's mental experience is precisely the idea behind some cleverly designed recent experiments. The researchers used not dogs, but that shopworn research subject, the laboratory rat. The behavior of rats in cages may be the single largest contributor to the corpus of psychological knowledge. In most cases, the rat itself is not of interest: the research isn't about rats per se. Surprisingly, it's about humans. The notion is that rats learn and remember by using some of the same mechanisms that humans use—but rats are easier to keep in tiny boxes and subject to restricted stimuli in the hopes of getting a response. And the millions of responses by millions of laboratory rats,
Rattus
norvegicus,
have greatly informed our understanding of human psychology.

But the rats themselves are intrinsically interesting as well. People who work with rats in laboratories sometimes describe their animals' "depression" or their exuberant natures. Some rats seem lazy, some are cheery; some pessimistic, some optimistic. The researchers took two of these characterizations—pessimism and optimism—and gave them operational definitions: definitions in terms of behavior that allow us to determine whether real differences in the rats can be seen. Instead of simply extrapolating from how humans look when pessimistic, we can ask how a pessimistic rat might be distinguished by its behavior from an optimistic one.

Thus, the rats' behavior was examined not as a mirror to our own but as indicating something about … rats: about rat preference and rat emotions. Their subjects were placed in tightly restricted environments: some were "unpredictable" environments, where the bedding, cage mates, and the light and dark schedule were always changing; others were stable, predictable environments. The experimental design took advantage of the fact that, hanging out in their cages with little to do, rats quickly learn to associate new events with simultaneously occurring phenomena. In this case, a particular pitch was played over speakers into the cages of the rats. It was a prompt to press a lever: the lever triggered the arrival of a pellet of food. When a different pitch was played and the rats pressed the lever, they were greeted with an unpleasant sound and no food. These rats, reliably like lab rats before them, quickly learned the association. They raced over to the food-dispensing lever only when the good-harbinger sound appeared, like young children rallied by the jingle of an ice-cream truck. All of the rats learned this easily. But when the rats were played a new sound, one between the two learned pitches, what the researchers found was that the rats' environment mattered. Those who had been housed in a predictable environment interpreted the new sound to mean
food;
those in unstable environments did not.