Dog Sense
Page 27
The next phase of the study was conducted in fourteen of the owners’ homes, where a test was set up to make the dogs look “guilty.” All of the dogs had previously been trained to take a food treat only when their owners gave them explicit permission. During the study, a treat was duly produced and the owner commanded the dog not to eat it. The owner then left the room. Once the owner was out of earshot, one of two things happened, depending on the experimental protocol: Either the treat was removed or it was handed to the dog with encouragement to eat it. Once there was no longer any visible evidence of what might have happened to the treat, the owner was invited back into the room.
The owners’ behavior was then manipulated to see how it affected their dog’s behavior. Just before they were allowed back into the room, the owners were told that the dog either had “stolen” the treat or had not stolen it. The owners were then encouraged to do whatever they would normally do in that circumstance; that is, they could praise the dog if they had been told that it had left the treat alone or admonish the dog if it had disobeyed and eaten the treat. Whether this was the appropriate behavior for the situation depended, of course, on whether or not the owners had been told the truth about what had happened when they were out of the room. The clever twist in this protocol was that all possible combinations were presented: “right”—dog scolded after actually eating the treat or dog praised for not eating and “wrong”—dog praised after actually eating the treat or dog scolded having not been allowed to eat. To avoid affecting the sincerity of their reactions, the owners weren’t told until after the experiment was complete that they had at times been deceived about what their dogs had really done.
The results were very clear-cut. The way the dogs behaved depended not on what they had or had not actually done but, rather, on the owners’ behavior, which in turn was based on what they believed their dogs had done. If the dogs had really experienced “guilt,” they should always have looked guilty after they had eaten the treat. In fact, they performed their “guilty” behavior (each dog was slightly different in this regard) only when the owner had been told they had eaten it and therefore scolded them—even when they hadn’t actually been given any opportunity to eat the treat. Moreover, the three dogs who were regularly physically punished (forced down, grabbed, or hit) by their owners when they disobeyed were those who performed the “guilty” behavior most intensely. The inescapable conclusion is that “guilty” behavior is in fact a mixture of fearful anticipation of punishment (hence the exaggerated behavior of the dogs who were physically punished) and attempts to reestablish a friendly relationship with the owner (hence the dogs’ “submissive” behavior such as rolling over, licking, and paw-raising).
So what is actually going on in these dogs’ minds, if they’re not feeling “guilty”? Let’s assume that they are using their default learning “rule” of associating events that occur very close together in time. So the dog understands this pattern: Owner comes home, owner punishes me, I can reduce the intensity of the punishment by performing affiliative (submissive) behavior. The next time the owner comes home, the memory of previous punishment triggers this affiliative behavior regardless of whether the owner has any intention of punishing the dog. All the dog understands is that on some occasions the arrival of the owner is followed by punishment and on other occasions it is not—in an apparently unpredictable way. As a consequence, the level of anxiety rises and the affiliative behavior becomes more frantic, the goal being to achieve reconciliation with the owner so that the anxiety goes away. We have no evidence to support the idea that dogs can, at such an intensely emotional moment, “think back” to what event in the past might be determining whether the normal friendly greeting is replaced by chastisement.
Misconceptions about canine emotion are an important issue in pet-keeping. In general, owners want their dogs to live up to the expectations they have of them; when the dogs do not, they may resort to punishing them—or even disposing of them. If such expectations are based on a misapprehension of what dogs are actually capable of, dogs have little hope of rectifying the situation, since they will have no comprehension of why their owners are behaving in a particular way. Hence their relationship is likely to deteriorate.
There are probably few problems in store for a dog whose owner mistakenly believes it is grieving, since the owner’s reaction will presumably be an affectionate one, but the misattribution of guilt can have serious consequences for the dog. Many dogs get upset at being left alone by their owners. As a consequence of the insecurity they feel when alone, they may do things that their owner will disapprove of—for example, chewing the frame of the door that the owner left through or trying to bury themselves under the sofa cushions and damaging them in the process. The returning owner sees the damage and immediately punishes the dog, thinking, almost certainly wrongly, that the dog will associate the punishment with the “crime” and thus not do it again. In fact, quite the opposite will occur: Because the punishment is associated with the owner returning, the anxiety felt during separation intensifies, making it more likely that the dog will be driven by its insecurity to do something the owner disapproves of while the owner is away. More punishment follows, and so a vicious cycle ensues (one that can last for years unless the owner seeks expert help). Indeed, a dog’s life can be ruined by a simple and easily corrected misunderstanding of its emotional intelligence.
However, it’s not just owners who have difficulty in interpreting and understanding their dogs’ emotions: Dogs themselves, given their inability to think dispassionately about how they’re feeling, are not good at dealing with their own emotions. Their lack of emotional sophistication manifests itself not only in their relatively limited emotional palette but also in their inability to rationalize such simpler emotions as fear. Unlike us, they cannot “tell themselves” that there’s nothing to be frightened of; they can’t calm themselves down. Nowhere is this more evident than in their irrational fear of loud noises.
Given that dogs have long been used as aids for game shooting, it’s surprising that so many of them are frightened of noises. (If there was any genetic basis to this fear, the expectation is that it would have been largely selected out by now.) Up to half the dogs in the UK react fearfully to fireworks, gunfire, and so on. Although some dogs probably habituate quickly to loud noises, so that their owners never notice a problem, many instead become sensitized. It’s perfectly natural for a dog to be fearful of a loud noise that happens without warning and with no identifiable source or cause. Yet this very unpredictability is what makes it difficult for the dog to know how to react. Unfortunately, whatever it does will be only partly effective; hiding behind the sofa may provide a feeling of protection, but it doesn’t serve to reduce the volume of the next bang very much. This inability to deal with the noise triggers an inability to cope, then an escalation of the emotional reaction and, in some dogs, the emergence of a full-blown phobia such that the triggering sound, even at a low level, will set off an extremely fearful reaction. Such phobias also occur in humans, of course, but their much greater prevalence in dogs is a sign of just how much dogs are at the mercy of their emotions when faced with situations that evolution has not prepared them for.
Dogs’ limited capacity for emotional self-control can therefore have real consequences for their welfare. Dogs cannot “pull themselves together.” Their instincts tell them to be frightened of sudden, novel events, and when they find such events incomprehensible (e.g., when they hear the loud bang of a firework from behind a closed curtain), they are not capable of dismissing the events as irrelevant. On the contrary, some dogs become more and more frightened every time. Similarly, since dogs lack the mental abilities to feel “guilt,” let alone its more abstract cousin “shame,” owners who punish them on the basis that they “obviously know they have done wrong” are doing them a great disservice.
The scientific exploration of canine emotions and moods is still in its infancy, but there will surely be new developm
ents in the near future. In particular, a new technique allowing dogs to tell us how they are feeling may have great potential (see the box titled “In the Mood?”). But there is little doubt that emotions are part of their minute-by-minute experience of their existence.
In the Mood?
In humans, anxiety and depression are associated with negative judgments of ambiguous situations—“the glass is half empty” syndrome. If such biases could be detected in nonhuman animals, they might provide a way of probing “moods” in these animals. Following up studies done on rodents, colleagues of mine at Bristol University have examined whether dogs might also show such biases.6 Twenty-four dogs awaiting rehoming at a rescue shelter were first given a separation test, which is designed to predict whether or not a dog will display separation behavior when left alone once it has been rehomed. The dogs were then trained to perform a spatial discrimination task in which one location always contained food (in the diagram, the white bowl to the dog’s left—although in actuality all the bowls were the same color) whereas another an equal distance away never did (in the diagram, the darkest grey bowl). Once the dogs had learned which of the two locations contained food, the two bowls were replaced with one (empty) bowl, which could be in any of five locations—two in the same locations as in the original training and three in intermediate “ambiguous” locations (shown as intermediate shades of grey). The dogs were then tested to determine how quickly they ran to each of the locations. Faced with a bowl placed in one of the three possible intermediate locations, a “pessimistic” dog might think “There’s nothing in that bowl, it’s not where the food was last time” while an “optimistic” dog might think “That bowl’s near the place where the food was last time, it’s worth giving a look.” The dogs who had exhibited separation distress when left alone ran slower than the rest, so they may be more “pessimistic” than average. It’s tempting to speculate that such pessimism is the crucial underlying factor that distinguishes dogs who can’t cope when left alone from those who can.
Finally, I must allow that even the detached, scientific approach to emotion that I have tried to adopt contains at least one residual trace of anthropomorphism: I have discussed emotions using the names that we humans give them. The most basic emotions are so rooted in mammalian physiology and the more primitive parts of the mammalian brain that it is reasonable to assume that they are fundamentally the same whether experienced by a dog or by a human, even though the details of that experience may differ. However, when it comes to the simpler self-conscious emotions, such as jealousy, can we be sure that dogs possess only those that we humans have, and can put a name to? While I am reasonably confident that dogs don’t feel guilt (as just one example), it doesn’t necessarily follow that their emotional lives are any less rich than ours—just different. For instance, since they are such social animals, maybe they compensate for their less sophisticated cognitive abilities by having more fine-grained emotions. If the Inuit can have fifteen words for snow,7 maybe dogs can experience fifteen kinds of love?
CHAPTER 9
A World of Smells
Show any dog lover a picture of a cute dog, and you’ll get an instant reaction. Show the same picture to a dog, and you probably won’t get any reaction at all. (Unless it’s your own dog, in which case you might get a puzzled expression that clearly signifies “Whatever are you up to?”)
Dogs may inhabit the same physical space as us, but they don’t experience the world the way we do. We like to think that our version is “the” version, but it isn’t. Like every other species, we pick up the information about the world that we need in order to survive, and we discard the rest. Or, more accurately, we pick up information that helped our primate and hominid ancestors survive. (We haven’t lived our current lifestyles for nearly long enough for our senses to have been modified by evolution.) Dogs live in a world that’s dominated by their sense of smell—one that is quite unlike ours, which is constructed around what we see.
It’s easy to ignore the fact that we, too, get an edited version of what’s going on around us. We can’t “see” the light beam that comes out of our TV remote control, but it does consist of light—it’s just that its wavelength is too long for our eyes to pick up. The mere fact that it’s invisible to us doesn’t mean it’s not there. Hence it’s worth reminding ourselves of what we do and don’t pick up from our surroundings before going on to consider what dogs could tell us about what we’re missing out on, if only they could talk.
First of all, we are color junkies, at least by comparison with most other mammals. Although we have only three types of cone—yellow-, green-, and violet-sensitive receptor cells (many animals have four, some even more), it’s been estimated that our eyes can distinguish about 10 million different colors. (When I say “our,” strictly speaking I’m referring only to men; some women, possibly as many as half worldwide, have a fourth type of receptor in the yellow-green area and thus are likely able to distinguish between millions more shades of red, orange, and yellow than the rest of us can.)
Our ability to see all these colors has evolved only recently. Although reptiles (and birds) can see the full range of colors as well as ultraviolet, sometime during the course of the early evolution of mammals the ability to see both ultraviolet and red disappeared. It’s possible that, because those early mammals were nocturnal, they needed the space on their retinas for rods—the receptor cells that are used in low-light vision, which are responsive only to black and white. The Old World monkeys and apes, most of which forage in daylight, “re-evolved” trichromatic vision about 23 million years ago, probably as a way of fulfilling the need to distinguish tender leaves and ripe fruits by their color alone.
What the eye can detect is only half the story: The brain still has to turn raw data into pictures. All the information gathered by our eyes is integrated together in the brain to form the three-dimensional color image that we consciously perceive as “seeing.” Although our brains can put together a 3-D image using the information from just one eye (try closing one eye and moving your head around very slightly), the most accurate and instantaneous information comes from our binocular vision. Our brains constantly compare the pictures coming in from each eye, using the small discrepancies between them to generate a full-color 3-D image. To make this process as efficient as possible, our eyes point in exactly the same direction. (This is unusual among mammals; even cats, with round flat faces like ours, have eyes that point slightly out to the sides, at about an eight-degree angle. By contrast, animals such as rabbits that primarily use their vision to detect approaching danger have eyes on the sides of their heads, sacrificing binocular vision completely in order to have the widest possible field of view.)
And so humans are extremely visual creatures. Scientists estimate that our brains receive about 9 million bits of information from our eyes every second—ten times as much as, for example, a guinea pig does. There are various theories as to why we evolved this ability; among them is the supposition that as primate society became more complex, the need to monitor everyone else in the group increased, resulting in especially detail-oriented visual acuity.
Although humans see more than most mammals do, we don’t hear nearly as much; hearing is evidently not as important for primates as it is for many other mammals. Mice and bats can hear much quieter and much higher-pitched sounds than we can, and dogs and cats can hear pretty much everything we can, and much more besides. We’re also not as good as most other mammals are at judging where sounds are coming from. Looking back to our evolutionary roots as hunter-gatherers, we can surmise that vision would have been much more useful than hearing for gathering edible plants and fruits—and for tracking game as well. However, our brains are probably much better than dogs’ brains when it comes to distinguishing between very similar sounds, a skill we’ve evolved in order to decode speech.
It’s our sense of smell that is really feeble compared to that of the rest of the animal kingdom (except birds). We can train
ourselves to discriminate between different smells, provided they are strong enough for us to smell in the first place, but most of the odor information in the world around us simply passes us by. As a consequence, apart from a few professionals such as wine tasters and perfumers, we don’t even have much of a language to describe the quality of odors.
Why is the human nose so insensitive? First of all, we have a tiny olfactory epithelium, which is the skin inside our nostrils that removes odor molecules from the air we breathe and sends messages to the brain about what they are. Secondly, the parts of the brain that deal with incoming odor information are greatly reduced in all the Old World primates and apes—and there has been, if anything, a further reduction during our own evolution. Thirdly, by comparison with almost all other mammals we have a very limited repertoire of odor receptors, which cuts down on the amount of subtlety we can extract from any particular odor. We still have the relics of the genes that mice (for example) use to make the much greater range of receptors that they possess, but our versions of these genes don’t work—indeed, they stopped working millions of years ago, during the evolution of the higher primates. As a result, although we can probably detect the same range of odors that mice can, we do so with less detail. And of course we also need much more of the odor to be present to smell anything at all.