Good Dog: Studies & Research
Individual variation explains a lot
Dogs are well known to be chowhounds. The idea that they love food more than anything else is practically (excuse the expression) dogma in the fields of canine behavior and dog training. The trouble is, recent research suggests that it is not true for all dogs.
In a study called “Awake Canine fMRI Predicts Dogs’ Preference for Praise Versus Food” scientists investigated whether dogs prefer treats or praise, and whether their choice can be predicted by their brains’ response to both stimuli. In one experiment, they measured the level of activation of the brain’s ventral caudate, an area known to function as a reward center, in response to items that predicted various outcomes. A toy car predicted that verbal praise was coming, a toy horse predicted that food on its way and a hairbrush was associated with nothing. Dogs were trained to make these associations with a series of 40 pairings of each object with what it predicted. The activation of the specific region of the brain was measured with functional Magnetic Resonance Imaging (fMRI), which is possible because the dogs in the study have all been trained to remain motionless while in the scanner.
The average activation of the reward center of the brain was higher in the food and praise conditions than in the neutral condition, which shows that the dogs did learn the associations between the objects and what the objects predicted. (Each dog’s responses in the brain to seeing the toy horse and NOT receiving the expected praise was also measured.) There were 15 dogs in this experiment, and most of them had a similar response in the reward center to the food or to the praise. Four showed a stronger response to praise and two showed a stronger response to food. The average response to praise and to food did not differ.
In another experiment, dogs were placed in a Y-maze and given the opportunity to choose which arm of the maze to go to. One arm led to a food bowl with treats and the other arm led to the dog’s guardian, who provided petting and praise. Each dog was tested in the Y-maze 20 times. Seven dogs in the study chose the guardian the more times than the food, and seven dogs chose the food more often. One dog chose the guardian and the food an equal number of times.
The relative value of praise versus food in the first experiment was highly predictive of the choices that dogs made in the Y-maze experiment. Dogs whose ventral caudate showed a strong response to praise were more likely to choose their guardian over food but dogs who did not show such a strong response to praise relative to food were more likely to head for the food when given a choice.
Regrettably, the results of this study have erroneously been reported in many places as proof that dogs prefer praise and belly rubs to treats, and suggested that using treats in training is therefore unnecessary. It has been written in many places discussing this study that 13 of 15 dogs prefer praise to food, and that’s not correct. What the researchers actually wrote is that in 13 of the 15 dogs, the ventral caudate showed either roughly equal activation to food and to praise or greater activation to praise than to food.
It’s quite interesting that roughly half of the dogs chose their guardian over food. For those dogs, social interaction such as praise and belly rubs may be more effective than treats in training. However, caution is important when acting on the findings in this study because the research may overestimate the response of dogs to their guardians relative to food in situations outside the laboratory setting.
The lab may have been stressful, causing a bias in dogs towards an increased interest in their guardians when compared with food. They may have been seeking comfort from their guardians in a way that they might not be during typical training situations. The scientists do point out that these dogs have been trained to stay still in the scanner and that the lab is a familiar environment. That does not mean the dogs are as comfortable as they are at home or in other areas such as on neighborhood walks, at the park or at the training center where they attend classes. It’s important to know what dogs choose in the actual training setting before changing what reinforcement to use based on lab research.
Additionally, although dogs may value social connections over food when the social interaction is with their guardian, not all training occurs between guardian and pet. I do a lot of training with dogs who I adore, but I don’t share quite the same bond with them as they do with their own guardian. So, just because dogs may prefer affection from their guardian over food does not mean that they prefer affection from just anyone over food. Finally, in many training scenarios, dogs receive praise in addition to food during training, and that may be more effective than either one alone.
Many people swear that their dogs prefer praise and petting to treats, and others are just as certain that food wins out every time with their dogs. Perhaps the most important lesson from this study is that individual variation in preferences is huge. If you feel strongly about what matters most to dogs, there’s a good chance you’re right—when it comes to your dog, anyway.
Do you think your dog would go for food or for praise and affection if given the choice?
News: Guest Posts
Not surprisingly, a study published July 29, 2016 found that the English Bulldog no longer retains enough genetic diversity to correct life-threatening physical and genomic abnormalities. This means breeders cannot use the established population of purebred dogs to reverse the trend in extreme and painful exaggerations such as crippling dwarfism and respiratory deformities - traits that uninformed pet-owners find appealing.
In the early 1800s Bulldogs were trained for bull-baiting, a particularly cruel and vicious sport. In 1835 the Royal Society for the Prevention of Cruelty to Animals convinced Parliament to enact the first animal cruelty law for the protection of domestic animals, including outlawing bull baiting.
As such, the Bulldog had outlived its usefulness. Like the pre-19th century Wolfhound that disappeared with the eradication of wolves in the British Isles, and the Tumbler whose demise was the invention of hunting firearms, the Bulldog was destined for extinction.
English Bulldog from 1890
But it was not to be. Beginning about 1840, the Victorian dog fancy's unabashed sentimentality was a catalyst for saving even the most formidable working breeds from their inevitable demise. Like many others, such as the Dachshund and Mastiff, Bulldogs went from working hard to hardly working.
Utility dogs were "refined" and transformed to fill jobs they weren't originally bred for - as show dogs and companions. Altered physical and behavior characteristics along with decreased levels of aggression were more compatible for their augmented duties as house pets.
English Bulldogs from 1920s
Beginning in the late 1890s, Bulldog breeders (and other breeders as well) selected small groups of genes from a diverse genome and created new breed-types. They were in effect increasing the odds that genetic anomalies would more likely be expressed to bring out exaggerated traits, like the Bulldog's baby-like face, corkscrew tail and affable personality.
As "desirable" aesthetic traits were selected for, other genetic variants including beneficial genes that contribute to overall health were eliminated from the gene pool, never to be reclaimed.
In the last few decades the most exaggerated traits in the Bulldog - the extreme brachycephalic skull and deformed skeleton- have become increasingly pronounced because naive consumers want that type of dog and consequently that's what many breeders select for.
Driven by economics, fashion, and uninformed decisions, breeders and buyers either ignore or are unaware of the genetic problems that have spread throughout the population.
The demise of the breed may not be a good thing for Bulldog-lovers, but it will thankfully put an end to the malformed and painfully crippled modern Bulldog we recognize today.
The good news is that some breeders are intent on bringing back the "Olde-Fashioned-Bulldogge".
Good Dog: Studies & Research
How Closely Are They Linked?
I’m interviewing a new client whose dog tends to bark and charge and nip the heels and dan- gling hands of retreating strangers. Her dog is smallish and stocky, with a coarse, medium-length coat of mottled blue-gray, black, white and brown. His nose and ears are pointy. While I reassure her that his behavior actually makes sense from his doggy point of view, a little voice in my head whispers, “What did she expect? She got a Cattle Dog.” I have little difficulty discounting the client’s own plaintive claim that she’s had Cattle Dogs all her life and this is the first one who’s acted this way. “You were lucky until now,” my little voice says, assuming those dogs were somehow the exceptions. But when another client complains that his large, square-headed, short-coated, yellow dog is growly around his food bowl, I take his statement that “none of my other Labs have done this,” at face value. The current dog is clearly the exception. After all, my little voice says, “everyone knows Labs love people.”
My little voice is probably wrong.
So why not use breed as the way to choose the particular puppy or dog who’s likely to help us fulfill the dream of taking a perfectly behaved, friendly dog to cheer the lives of people in nursing homes, be endlessly tolerant with our kids or have the kind of indefatigable enthusiasm for retrieving that makes a good contraband-sniffing dog? How about using breed stereotypes to guide public policy decisions on whether some dogs are more likely than others to present a danger to people, or simply to assess whether that dog coming toward us means us good or ill?
Turns out it’s not that simple.
And even reliable identification of the ancestry of a mixed-breed dog by itself wouldn’t help us predict an increased likelihood of known, genetically driven traits — say, the blood-clotting disorder that plagues Dobermans or the heart defects of Cavaliers. The parents of any mixed-breed dog have, by definition, waded out of the closed gene pool that makes purebred dogs such fertile ground for genetic research. The inevitable inbreeding of purebred populations, combined with a phenomenon called genetic drift, gradually decreases overall genetic diversity; more and more animals have fewer and fewer variable traits, including characteristics that aren’t deliberately selected for or against. But as researchers found with a colony of wolves in Sweden, even inbreeding so severe that it causes infertility can be reversed by the introduction of just one outsider. So, if we could demonstrate such a thing as “acting like a Beagle” or “acting like a Basenji,” there would be little reason to expect either one from the offspring of a Beagle/Basenji pairing.
But what about those purebred Basenjis and Beagles and Cattle Dogs and Afghans and Golden Retrievers? Can’t we expect them to behave consistently in ways that resemble the work at which they were once selected to excel?
Yes and no.
And yet, every single one of her ancestors, going back scores, perhaps even hundreds, of generations, was hyper-motivated to chase. They would not have had the opportunity to reproduce otherwise. Racing Greyhounds are bred for two things only: a keen inclination to pursue small, fast-moving furry things and the physical ability to do it at great speed. Racing industry insiders estimate that only about 70 to 80 percent of the dogs who result from this ruthless selection process are keen enough to race. Now, a 75 percent incidence of a trait sounds pretty high. You’d certainly take those odds in Vegas at the roulette wheel. But this is a trait that’s already extremely common across the species; it is, in all likelihood, the most widespread of the predation behaviors of hunting, stalking, chasing, killing, dissecting and eating first observed and described by the famous wolf ethologist, David Mech. Most dogs already do this. If you take more complex behaviors that are actually selected against in the wild, like compulsively fighting other dogs and failing to respond to the doggy body language equivalent of “crying uncle,” for example, your odds of reliably producing the behavior through artificial selection go down dramatically. This explains how so many of the so-called “game-bred” dogs from fight busts (like the ones rescued from Michael Vick’s fighting operation) have gone on to live companionably with other dogs as relative couch potatoes in normal homes.
Reliably increasing the likelihood of complex behaviors through selective breeding isn’t easy. And racing Greyhounds are one of only a handful of dog breeds where this is still even attempted. Since the advent of modern purebreds in the late 19th century and the subsequent closing of breed registries, selection criteria have focused almost exclusively on appearance. Qualities of temperament are sometimes mentioned, although not in ways that can be practically applied in the show ring, where — as biologist Ray Coppinger has pointed out — the behavior required is standing, and to a lesser degree, trotting alongside a handler. Most purebred dogs come out of this selection system.
So these days, when people look fondly at the breed they fancy or angrily at the one they fear and say to me, “They’re not like other dogs,” I remind my little voice to recite, “Well, actually, they kind of are.”
News: Guest Posts
Reason number I’ve-lost-count that dogs are better than pretty much everything else: They’re sniffing out health disasters waiting to happen — and once again proving they are true lifesavers.
Studies out of Cambridge University and the University of Oxford have revealed new findings about a chemical called isoprene. It seems levels of isoprene rise when blood sugar levels fall, and its scent can be detected by dogs on human breath. Which is excellent news for Type 1 diabetics and for parents of children with diabetes.
Diabetics are particularly susceptible to experiencing life-threateningly low levels of blood sugar while they sleep. But Diabetic Alert Dogs, as they’re called, are trained to watch over diabetic kids during the night. If a dog detects the smell of isoprene, she’ll first try to wake the child. If there’s no response, the dog is trained to then go alert the parents.
According to a report in the Endocrinology Advisor, the new role for humans’ best friend is proving incredibly valuable: “Diabetic alert dog owners as a whole have expressed high satisfaction and confidence in their canine guardians.”
So now, in addition to lowering blood pressure and sniffing out certain types of cancer, preventing hypoglycemic episodes can be added to the list of dogs’ health-preserving abilities. Indeed, their noses remain a step ahead of science. Pretty amazing for a species who asks for so little from their human partners.
Good Dog: Studies & Research
Studies on dogs following gestures.
AT TWO WEDDINGS, darling ring bearers paraded down the aisle proudly holding the prized objects. They couldn’t have been more than six. When they suddenly stopped—as six-year-olds tend to do—to look at something on the ground, guests leaned into the aisle and pointed toward the beaming faces ahead. Smiles filled the crowd as they continued on their way.
At one wedding, the ring bearer was a little boy, and at the other, a dog.
If we’ve spent any time with companion dogs, we aren’t surprised when a dog stops to check out the ground. It also shouldn’t surprise us that a dog might go where we point. Pointing is about social communication, and it often feels like dogs are right there with us, sometimes even more than members of our own species.
In the last 20 years, dogs’ attention to our communicative gestures—particularly this thing we do with our arm and finger—has attracted enormous attention from researchers around the globe. In fact, the pointing gesture is so fundamental that seemingly no article on the canine mind is complete without a sentence such as “dogs read our gestures, like pointing, more flexibly than any other animal” (New York Times), or—more boldly in Time—“While chimps and even wolves lack an innate ability to understand what pointing means, dogs come by the knowledge naturally.”
These statements tend to produce any number of reactions in dog owners, from “Obviously,” sometimes accompanied with a side of, “Why do they bother to do this research anyway?” to the flip side: “My dog doesn’t do that … what are they talking about?” Or even the more nihilistic view: “Sure they do, but who cares?”
Here’s why we care: this one little gesture, in all its complexity, could be a core feature of the intimate bond we share with dogs.
Since the late 1990s, researchers have tried to uncover why and how dogs pick up on our cues. Initially, key questions focused on whether their ability to follow the pointing gesture arose from our long-standing co-evolutionary history or, alternatively, if they learned the behavior over the course of their individual lives.
Pointing Is About Us
Pointing is something we humans do as part of our social communication, and it is useful only because we all agree on how it should be interpreted. Imagine if your point were perceived as, “Hey! Check out my fingertip. No dirt under my nail. Wonderful, huh?” Not exactly useful for communication. Fortunately, we understand that pointing creates a shared experience beyond our fingertips; pointing draws someone’s attention past our outstretched index finger to something out there in the world.
This cooperative gesture serves us well. Yelling, “Look out!” is only somewhat informative, but yelling, “Look out!” and pointing can help a fellow human locate and respond to a Frisbee sailing in at head level or Godzilla rampaging down Fifth Avenue. Communication achieved.
Despite our mothers’ reminders that pointing is rude, it has a function: it reflects our ability to hold shared attention with others, which could also indicate that someone else is aware of the same thing that we are. Pretty meta. Joint attention can thus be associated with an ability to infer others’ mental states, which is considered an important social capability in humans.
At about six months, children start following the gaze and gestures of others. We start pointing around our first birthday and become increasingly point-savvy as we age. When toddlers see something of interest and point at it, they become excited when we also look. They will also point when seeking something or to provide information (I want that. You dropped something). Regardless of how it’s used or understood at any given age or moment, pointing intrinsically aids our communication with one another.
Do Dogs Get the Point?
It shouldn’t come as a surprise that much of the academic interest in the canine mind that blossomed in the late 1990s was actually largely about us, investigating to what extent dogs responded to our communicative gestures— notably, our pointing. In research labs around the world, it has been a pointing party ever since.
Watch any program covering research into the canine mind and you’re bound to hear mention of studies involving a dog, two cups and a pointing human. The experiment, commonly referred to as the object-choice task, follows some variation of this procedure: a dog first learns he can get a treat for approaching either of two identical cups. He then watches as a person points to one of the cups. Will the dog follow the point to the cup?
Human children are quite good at this task, and numerous studies confirm that dogs are, too. From an early age, dogs are highly responsive to this gesture. Dogs do well when a person points with a foot, or bows or nods. They’ll also respond to what’s commonly referred to as a “momentary” point, in which the person points and then lowers his or her arm before the dog makes a choice. They will follow the point even when a person stands by one cup and points at the other. Although we all know smell is a major player in the canine world, it doesn’t appear to factor greatly into dog performance; when food is hidden under one cup and nobody points, they don’t do so well. Some researchers describe their performance as “remarkable” and “outstandingly flexible.”
Not all species catch our communicative drift. A bee that flies into your car will never be aided by your outstretched arm pointing toward the open window. Given dogs’ long history with us, researchers wondered whether canine sensitivity arose through the domestication process—in which case, wolves, their closest relative, might be less adept in this task—or, on the other hand, whether it’s a product of learning and dogs’ individual life experiences. Or maybe the reality is not so black-and- white. What underlies their highly flexible ability?
Wolves do not follow our gestures as flexibly as dogs. Nor do chimpanzees, our closest relatives. This isn’t to say that wolves (or chimpanzees) can’t or don’t do it. Extensively socialized wolves and enculturated chimps—those highly familiarized with human behavior— can follow our points, but dogs generally respond more readily and easily, and wolves need more exposure to perform similarly. In 2002, Brian Hare of the Duke Canine Cognition Center pulled together then-current research on dogs, wolves and chimpanzees and, in an article in Science, concluded, “Dogs’ social-communicative skills with humans were acquired during the process of domestication.”
Both Nature & Nurture Point to Success
More immediate genetic influences, like artificial selection, could also influence dogs’ skills. Márta Gácsi and colleagues at the Family Dog Project in Budapest found that while all dogs tested followed the point better than chance would predict, dogs bred for cooperative work (like gun dogs) performed better than those bred for independent work (like guard dogs). All the dogs in the study were living as pets and none had received special training, implying that genetics plays a role at some level in enhancing dogs’ ability to follow our gestures.
At the same time, individual life experiences could also contribute to a dog’s responsiveness. For example, the reactions of shelter dogs to our pointing gestures vary widely, and a small group of intensively socialized lab-raised dogs did not fare well in the task.
Lucia Lazarowski of the Comparative Cognition Laboratory at Auburn University, one of the investigators in the lab-raised dog study, saw their challenges first-hand. But when she later adopted Captain, a study participant, and informally examined his responsiveness to pointing, she found he performed much better in her home: “He actually looked in the direction I pointed and sniffed in the area I was pointing to. During the test, however, he was one of the more non-responsive dogs. Now, we like to play a game where I toss small treats around the room for him to hunt, and if he can’t find them, sometimes I’ll point to them, so he probably has picked it up from that.” Captain’s transition to canine pointfollower highlights that learning and life experiences can factor into the skill.
The person behind the point can also affect dog performance. Amy Cook, CDBC, CPDT-KA, conducted a study on the topic at the University of California, Berkeley; reporting in Animal Cognition, Cook noted that when owners and strangers were pitted against one another (in what I hope was described as a “point-off”), dogs tended to follow their owners, even when they received no reward (i.e., the point did not lead to the dog getting food). As Cook explains, “Dogs make decisions by attending preferentially to social signals from humans with whom they have become more familiar.” Many of us think it’s all about us, and our dogs might agree.
If dogs respond to the pointing gesture based on whose finger is doing the work, then again, it looks like life experiences could be controlling the switches. But not so fast: Cook suggests that this unique spin on the issue— dogs being more attentive to a familiar person—could have been shaped by evolutionary pressures to bond with a caretaker. Attachment relationships between dogs and their humans are well documented and, as Cook says, going with your person could be “a successful strategy in the long term.”
Isn’t it nice when everyone can be right? Dog responsiveness to our communicative gestures could be a product of their evolutionary history plus their ability to learn rapidly once in a human environment. In a 2009 article in Behavioural Processes, Pamela Reid, CAAB and vice president of the ASPCA’s Anti-Cruelty Behavior Team, reflects on what’s behind canine responsiveness to our social cues: “Dogs are too skilled for it to be pure trial-and- error learning. Yet it is improbable that a versatile behavior like this would be largely innate.” She suggests that what we see in dogs is an adaptive specialization of learning. “In essence, they come with a built-in head start to learn the significance of people’s gestures, in much the same way that white-crowned sparrows acquire their species-typical song and ducklings imprint on their own kind.” This fits in well with what is understood of instinctual or innate behaviors. As Jack Hailman explained in his inf luential piece in Scientific American in 1969, “How an Instinct Is Learned,” species-specific behaviors require some amount of experience and development.
When Patricia McConnell, CAAB, mulled over the pointing research on her blog, “The Other End of the Leash,” she agreed that dogs could be “predisposed to learn to follow a pointing gesture.” McConnell also highlights something you might have seen yourself: present a very young puppy with an outstretched finger and that puppy is going to approach your fingertip, not follow it to a distant location. McConnell’s point is that point-following in puppies is not automatic, although they learn it very easily.
To this, Reid adds, “Just because a skill appears early in development does not preclude learning. It does, however, demand that puppies be highly attentive to the actions of humans, a tendency that has been confirmed in studies of dog-human attachment.”
What Do You Understand, Dog?
What do dogs think of all this? What does it mean to be a dog who “understands” our pointing gesture?
A 2013 article by Ádám Miklósi and József Topál of the Family Dog Project in Trends in Cognitive Sciences concludes by highlighting that “dog social competence [appears] sometimes ‘infant-like’ or ‘human-like,’ but, importantly, the underlying mental mechanisms may turn out to be quite different.”
It’s hard enough for us to figure out if, for example, our boss is merely suggesting that we do something or telling us to do it. The same is true for dogs and the pointing gesture. Do dogs see pointing as an imperative—“You. Go there.”—or as simply providing information or a helpful suggestion—“I recommend that you go there.”—a subtle yet meaningful difference. A 2011 article published in Applied Animal Behaviour Science by Helene Pettersson and colleagues found that, like children, dogs are more likely to follow a point when it is accompanied by a cooperative tone of voice as opposed to a prohibitive tone. At the same time, dogs sometimes follow the point to an empty container, leading some to wonder whether, under certain circumstances, dogs might perceive the gesture as a command.
Like humans, dogs seem to distinguish when communication is—or is not—intended for them, although they could be relying on a more limited set of cues. Numerous studies find that initiating eye contact and using high-pitched vocalizations help dogs understand that the communication is for them. Setting is also important. In a 2011 study reported in PLoS ONE, Linda Scheider and colleagues found that if a person points to a location where a dog has never experienced reinforcement, the dog is not as likely to follow as he would be if he had previously received reinforcement there (making me wonder whether the ring-bearer dog would spontaneously follow the point to the altar).
At some level, every pointing gesture suffers from a fundamental ambiguity: we might be pointing to a particular object, or we might be pointing to a specific space that happens to be inhabited by a particular object. Usually, we can figure it out without too much cognitive difficulty. Even nine-monthold infants understand when pointing refers to an object as opposed to the place where the object is located.
How about dogs? In a study recently published in the Journal of Comparative Psychology by Tibor Tauzin and colleagues, an experimenter pointed at one of two different toys on either side of him. Before the dog could approach, the experimenter switched the location of the objects in full view of the dog. The researchers wondered whether the dog would approach the object that had initially been pointed at but that was now in a new location, or to the original location of the point. The result? Dogs did not follow the object to its new location. Instead, they approached the old location, which seems to imply that, for the dog, pointing could be more about the location than the pointed-at object.
For those of us who live or work with dogs, much of the value of pointing studies lies in what we do with the results. Despite being unflashy, the pointing gesture is actually rich in dimensions and angles that we can explore with our dogs. As Reid recommends, “Take note of your body gestures. Does your dog attend to your gestures in all cases, or only in certain contexts? Dogs are often way more sensitive than we can grasp. They’re not trying to fool you or trick you, get one over on you or cheat the system. Attending to our gestures is just what dogs do. It’s who they are.”
Cook, A., et al. 2014. My owner right or wrong: the effect of familiarity on the domestic dog’s behavior in a food-choice task. Animal Cognition 17: 461–470.
Franco, F., and G. Butterworth. 1996. Pointing and social awareness: declaring and requesting in the second year. Journal of Child Language 12(2): 307–336.
Gácsi, M., et al. 2009. Effect of selection for cooperation and attention in dogs. Behavioral and Brain Functions 5:31.
Hailman, J.P. 1969. How an Instinct Is Learned. Scientific American 221(6): 98–106.
Hare, B., et al. 2002. The domestication of social cognition in dogs. Science 298(5598): 1634–1636.
Hochman, D. 2014. You’ll Go Far, My Pet. New York Times, April 11.
Kaminski, J., et al. 2011. How dogs know when communication is intended for them. Developmental Science 15: 222–232.
——— and J. Nitzschner. 2013. Do dogs get the point? A review of dog-human communication ability. Learning and Motivation 44(4): 294–302.
Lazarowski, L., and D.C. Dorman. 2015. A comparison of pet and purpose-bred research dog (Canis familiaris) performance on human-guided object-choice tasks. Behavioural Processes 110: 60–67.
Miklósi, A., and J. Topál. 2013. What does it take to become ‘best friends’? Evolutionary changes in canine social competence. Trends in Cognitive Sciences 17(6): 287–294.
Pettersson, H., et al. 2011. Understanding of human communicative motives in domestic dogs. Applied Animal Behaviour Science 133(3-4): 235–245.
Reid, P. 2009. Adapting to the human world: Dog’s responsiveness to our social cues. Behavioural Processes 80(3): 325–333.
Scaife, M., and J.S. Bruner. 1975. The capacity for joint visual attention in the infant. Nature 253: 265–266.
Scheider, L., et al. 2011. Domestic dogs use contextual information and tone of voice when following a human pointing gesture. PLoS ONE 6(7): e21676.
———, et al. 2013. Do domestic dogs interpret pointing as a command? Animal Cognition 16: 361–372.
Tauzin, T., et al. 2015. What or where? The meaning of referential human pointing for dogs (Canis familiaris). Journal of Comparative Psychology 129(4): 334–348.
Udell, M., et al. 2008. Wolves outperform dogs in following human social cues. Animal Behaviour 76: 1767–1773.
Zimmer, C. 2009. The Secrets Inside Your Dog’s Mind. Time, September 21.
Good Dog: Behavior & Training
Differential use of the left and right nostril
The common wisdom that dogs can smell fear doesn’t give dogs full credit to the nuances of their ability to sense emotion through their noses. A recent study titled “The dog nose “KNOWS” fear: Asymmetric nostril use during sniffing at canine and human emotional stimuli” examined dogs’ tendencies to sniff various substances with the right or the left nostril. Exploring this side bias may seem like looking at random details, but the side of the nose used to sniff something tells us a lot about the dog’s emotional reaction to the odor. The use of one side of the body indicates a differential use of one side of the brain or the other, which is a clue to the dog’s emotions.
The left side of the brain processes more positive emotions such as happiness and excitement as well as stimuli that are familiar. The right side of the brain tends to take over when a dog is processing negative emotions such as sadness or fear as well as novel stimuli. In general, the right side of the body is controlled by the left hemisphere of the brain and vice versa. However, the nose is an exception; the right nostril sends information to the right side of the brain to be processed and the left nostril sends its information to the left side. The findings of this study suggest that the pathways used to process various olfactory stimuli are dependent on more than just whether they elicit negative or positive feelings.
Eight odors were tested—four from dogs and four from humans. The four human odors were collected as sweat from donors who were joyful, fearful, physically stressed, or in a neutral situation. The joyful and fearful states were elicited by movies, and the physical stress odor was collected after donors ran for 15-minutes. The four canine odors were collected from dogs who were happy following a play session with the guardian, stressed by isolation in an unfamiliar place, disturbed by a stranger approaching the car, and dogs who were asleep. The dogs who “donated” odors were different from the dogs whose sniffing behavior was studied.
To further explore the phenomenon of side bias in sniffing, the guardians of the dogs in the study filled out a questionnaire related to each dog’s temperament. During the study, dogs were led to a video camera under which was mounted a Q-tip saturated with various odors. The videos captured the dog’s sniffing behavior so that it was possible to determine a laterality index for each dog for every odor based on the amount of time spent sniffing with each nostril. A laterality index of 1.0 indicated exclusive use of the left nostril and negative 1.0 indicated exclusive use of the right nostril. Dogs’ cardiac activity was also recorded during the tests of each odor.
I’m sure it’s the science geek in me, but I got a kick out of reading the sentence, “Results for nostril use are shown in Figure 2.” Three of the odors elicited consistent sidedness in nostril use and five of them did not. Dogs more frequently used the right nostril to sniff the canine isolation odor. They more frequently used the left nostril to sniff the human fear odor and the odor from human physical stress.
There were two ways in which the results of the questionnaire were correlated with the laterality pattern for a particular odor. The higher a guardian ranked the dog’s fear/aggressiveness to other dogs, the more likely that dog was to use the right nostril for sniffing the disturbed canine odor. This suggests that individual differences in emotional arousal and perhaps even in temperament influence asymmetries in sniffing behavior. Dogs with higher scores for predatory behavior used the left nostril more for sniffing the odor that came from physically stressed humans. This makes sense when we consider that it is structures in the left side of dogs’ brains that are involved in predatory behavior.
Dogs’ brains are every bit as amazing as their noses, as research about both of them reveal!
Good Dog: Behavior & Training
Natural detection task is very revealing
We all know that Beagles have better noses than Whippets, right? This almost seems too obvious to point out, especially to anyone who has ever had a dog of either breed. However, the authors of a recent study claim to be the first to scientifically document a difference in olfactory abilities across groups of dogs.
The researchers compared scenting ability across four groups of canines: dog breeds that have been selected for scenting abilities, dog breeds that have not been selected for scenting abilities, short-nosed dogs and hand-reared wolves. The task asked of these animals was simple—find the raw meat in a container that is hidden underneath one of five pots. There were multiple tests that varied in difficulty based on the number of holes in the container’s lid.
The results of the study were that dogs bred for scenting ability performed better than both short-nosed dogs and dogs who were not bred for their olfactory capabilities. The short-nosed dogs performed worse than any other group, suggesting that breeding for this head and face shape has adversely affected olfaction. In the most difficult of the tests, only wolves and the dogs bred for scenting abilities performed better than what would be expected if the animals were just guessing. Wolves improved their performance when they were re-tested, but the dogs in all three groups were no better the second time around.
Since dogs did not improve with repeated testing, this test may be a useful one-and-done way to assess a dog’s scenting capabilities. That is important because there is currently no standard method for testing the olfactory ability of dogs, but the method in this study could be used for quick assessments of dogs’ abilities. Most ways of testing dogs involve a match-to-sample design, which means that the dogs are taught a scent and they then have to find the same scent from among a group of scents. That requires extensive training, so it is impossible to determine to what degree those tests are assessing trainability and to what extent they measure scenting ability. Both trainability and olfactory ability are important for success as a working detection dog, but there’s great value in evaluating each trait independently.
News: Guest Posts
An international group of scientists proposes dual domestication from wolves.
Among the many hotly debated topics related to the appearance of dogs in the lives of humans is how often and where it first occurred. In their landmark 1997 paper on dog origins, Robert K. Wayne, Carles Vilá, and their colleagues made the case for multiple origins, but many other students of dog evolution, including Peter Savolainen, a co-author on that paper, have repeatedly and strongly argued for a single place of origin.
In this week’s Science magazine (June 3, 2016) [the article is available here, gratis], Laurent Frantz of Oxford University’s ancient dog program, writing for more than a score of his colleagues from institutions around the world, presents the case for dual domestication of Paleolithic wolves in Western Eurasia and Eastern Asia. According to this hypothesis, a now extinct ancestral wolf split into at least two genetically distinct populations on opposite sides of the Eurasian continent where they encountered and joined forces with humans to become dogs.
Frantz and his coauthors pin much of their argument on analysis and comparison of the fully sequenced genome of a 4,800- year old dog unearthed at Newgrange, Ireland, to other ancient and modern dogs and modern wolves. They found it retained “a degree of ancestry” different from modern dogs or modern wolves. Using that and other evidence the researchers argue that the most comprehensive model for the appearance of the dog involves at least two domestication events 15,000 or more years ago. Frantz writes: “The eastern dog population then dispersed westward alongside humans at some point between 6,400 and 14,000 years ago, into Western Europe (10,11, 20), where they partially replaced an indigenous Paleolithic dog population. Our hypothesis reconciles previous studies that have suggested that domestic dogs originated either in East Asia (9, 19) or in Europe (7).”
I asked Greger Larson, co-director of the Oxford project and corresponding author on the paper, just what were the boundaries of “Western Eurasia,” comprised apparently of Europe and the Middle East, and “Eastern Asia?” He answered in an email that the boundaries were left deliberately vague because where wolves became dogs remains unknown, like the date itself.
In Science, Frantz writes: [W]e calculated the divergence time between two modern Russian wolves used in the study and the modern dogs to be 60,000 to 20,000 years ago.” The first number puts the dog in the time when Neanderthal was still the big kid on the European block, raising the possibility that Neanderthal had protodogs or that early modern humans came to Europe with dogs or soon allied with wolves. Either of the first two prospects must have set off alarms in some circles for Frantz cautions that those dates should not be taken as “a time frame for domestication” because the wolves they used may not have been “closely related to the population(s) that gave rise to dogs.”
Fundamentally, this paper is at once a bold attempt to come up with a workable hypothesis to explain the appearance of the dog in human affairs and a tentative step into troubled waters. Left unanswered are virtually all outstanding questions regarding the who, what, when, where, and why of the transformation of wolves to dogs. Geographically all it does is exclude Central Asia. Whether it does so wrongly may depend on how you define Central Asia geographically.
What makes it bold and radical even is the suggestion that early humans and wolves could have gotten together wherever and whenever they met on the trail of the big game they were following. There are many reasons for that including similar social and familial cultures, but humans and wolves could have joined forces to have become more successful hunters. We learn from Wolves on the Hunt: The Behavior of Wolves Hunting Prey by L. David Mech, Douglas W. Smith, and Daniel R. MacNulty (Chicago, 2016) that while wolves appear excellent at finding and trailing game, they are not very good at making the kill, succeeding perhaps half the time. It is dangerous work at which humans with their weapons excel.
Imagine the scene: Human hunters locate wolves on the hunt by watching ravens who are known to follow them. Human hunters move in for the kill and take as many animals as they can. If smart, they might share immediately with the wolves. If not, the wolves might consume what the humans do not carry off or follow them back to their encampment to take what they can.
The rest is a tale of accommodation through socialization—the ability to bond with another being—and all that entails.
This article originally appeared in Psychology Today's Dog's Best Friend, used with permission.
We may think our dog wIll take a treat from any hand that offers it, but a new study by a team of Japanese researchers suggests that may not be the case. Primates engage in something called “social eavesdropping”— essentially, making judgments about others based on interactions that don’t directly affect their own interests. This study tested dogs’ ability to do the same by setting up situations in which the dogs’ owners asked for help in opening a box and were assisted (helper scenario), rejected (non-helper scenario), or ignored (control scenario) as the dogs looked on. After these interchanges, when the dogs were offered treats, they took them randomly from Helper and Control “strangers” but were biased against non-helpers. According to Kazuo Fujita, professor of comparative cognition at Kyoto university and one of the study’s authors, the ability to socially and emotionally evaluate others “is one of the key factors in building a highly collaborative society.” So, another step in the process of understanding how Canis lupus became familiaris: like humans, dogs are able to pick up clues about who to trust and who to avoid.
Good Dog: Behavior & Training
Technology facilitates communication
What if dogs could talk? Specifically, what if service dogs and bomb-sniffing dogs could talk? Associate Professor Melody Moore Jackson at Georgia Tech, and a team that includes Professor Thad Starner, Research Scientist Clint Zeagler, and Jackson’s Border Collie Sky, are developing technology that allows dogs to say anything we give them the capability of saying. They’ve called their project FIDO, which is short for “Facilitating Interactions for Dogs with Occupations.”
They developed a vest with sensors on it that dogs can activate to communicate. The vest can play a message or send a text to a smart phone. From a training perspective, it’s a basic system—dogs are trained to hit specific sensors in response to certain cues. So, if asked which toy a person is holding, the dog can hit a sensor that plays a message that says, “That is the Frisbee®” or “That is the ball.” That is a cool trick, but the real genius of this vest is the variety of messages dogs can send.
For example, a service dog for a hearing-impaired person might hit a sensor in response to an alarm that sends a text saying, “I heard the alarm,” and a different sensor in response to the doorbell so that the message reads, “I heard the doorbell.” Many hearing impaired dogs lead their person to the source of a sound, such as a crying baby. This vest adds to the benefits of a service dog because it would also allow a person to be notified of a sound that is not reachable, such as a tornado siren. Just like distinguishing between the ball and the Frisbee®, telling these sounds apart is a type of discrimination task, and is the basis for many of the ways that this vest can be used.
For example, detection dogs are usually trained to bark if they find what they are looking for, perhaps a drug or an explosive. Although dogs are often trained to search for multiple types of drugs or explosives, they are limited in their ability to communicate the details of their finds to their handlers. It can make a big difference to everyone’s safety if the dog can let a handler know that the bomb is a stable type or an unstable one that needs careful handling. This vest can allow a dog to share more specific information.
This group developed a vest that allows a dog who has found anyone trapped after a natural disaster to activate a sensor with a message for that person to hear. The message lets the trapped individual know that help is on the way. Work is underway to develop a vest that allows a dog to activate a sensor that sends GPS coordinates to a handler. This allows the handler to join the dog, who does not have to leave the person who has been found. That could be lifesaving for a child who is hiding or for a person who is unable to move for whatever reason.
Similar technology could benefit people with any number of health problems. Imagine that a person with epilepsy has a seizure and the service dog has been trained to activate a sensor in response to that situation. The activation of the sensor would result in a call to 911 and also send a message to a family member. The message would include GPS coordinates and say, “My person had a seizure and 911 has been contacted.”
The possibilities of this technology are limitless. A dog could be trained to hit a sensor in response to someone saying, “Get help.” When that sensor is hit, a recording plays so anyone nearby hears, “My owner needs your attention. Please follow me.” This technology is very exciting because it allows dogs to communicate specific helpful information to people. The beauty of the design is that it is relatively easy to teach dogs with a solid base of training to activate sensors in response to specific cues. These vests represent a wonderful blending of solid dog training with new technology to increase the ability of dogs and people to accomplish a variety of tasks together.
Copyright © 1997-2016 The Bark, Inc. Dog Is My Co-Pilot® is a registered trademark of The Bark, Inc