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Dog's Life: Lifestyle
Human Point of View
Dogs’ behavior suggests they understand it

Dogs take the human perspective into account when deciding whether to take food that they have been told not to take. This is the conclusion of a recent series of experiments by Juliane Kaminski, Andrea Pitsch and Michael Tomasello described in a research paper called Dogs Steal in the Dark.

The experiments all had a similar set up, in which a dog was in a room with a food item on the floor. Dogs were pre-tested to ensure that they understood the cue not to take the food. They were told not to take the food and then the experimenters recorded whether the dog took the food or not and if so, how long it took for them to do so. In the first experiment, a human was present in the room and there were four conditions: 1) the food and the human were both in darkness, 2) the food was illuminated but the human was in the dark, 3) the food was in the dark but the human was illuminated, and 4) the food and the human were both illuminated.

The dogs took the food most often when both the food and the human were in darkness, and least often when they were both illuminated. The dogs took the food faster when it was not illuminated, but whether or not the human was illuminated had no effect on the time until the food was taken. These results suggest that the level of light in the room had an influence on the dogs’ behavior.

In the second experiment, the food was either illuminated or in the dark, but the human left the room after giving the cue not to take the food. The goal of this experiment was to determine if dogs were avoiding food when it was lit. The results were that the dogs almost always took the food no matter what light situation it was in, but they took it faster when it was illuminated than when it was in the dark. This indicates that the dogs are not simply avoiding food that is illuminated.

In the third experiment, the researchers investigated whether the overall amount of light in the room was important to dogs or whether they were responding to the specific location of the illumination. There were two different situations tested. For one group of dogs, the human in the room was always illuminated. Half the time, the food was illuminated, and half the time the light was directed at another spot in the room. For the other group of dogs, the human in the room was always in the dark and half the time, the food was illuminated, and half the time the light was directed at another spot in the room.

In this study, whether or not the human or the food was illuminated had no influence on the likelihood that the dogs took the food, but they waited longer to take the food when it was illuminated. This suggests that the location of the lit area matters, as opposed to dogs just reacting to the overall amount of illumination in the room. This shows that the visibility of the human is not the factor that causes the difference in behavior.

Overall, the conclusions drawn from these studies are that dogs do take into account illumination when taking food that they have been told not to take. Dogs were more likely to take the food when it was dark compared to when it was light. They took the food faster when the food was in darkness when a human was present, but took the food faster when it was illuminated when they were alone. Whether or not a human in the room was illuminated did not affect their behavior.

This research supports the idea that dogs are aware of and consider the human point of view when deciding whether to take food or not. To put that into a larger context, this relates to the ever-increasing body of evidence that dogs have a theory of mind, meaning they have an understanding that other individuals have different perspectives, knowledge and emotions.

This is very well done research that teases apart a number of variables to add to what we know about the canine mind. Unfortunately, most of the articles in the popular press only say, “Dogs steal more food in a dark room than in a light room,” which is a huge oversimplification of the complexity of this interesting work.

News: Guest Posts
Remains of a 33,000 year-old dog found in Siberia

I had watched the dog origin wars as a chronicler of the dog-human relationship for several decades when in 2009 I was approached a young editor The Overlook Press about writing a book on the origins of the dog.  I readily agreed, and the result was How the Dog Became the Dog.

Pondering the conflicting dates, places, and theories associated with the emergence of the dog, I concluded that as soon as our forebears met wolves on the trail they formed an alliance of kindred spirits, and the process began.  Their basic social unit was a family with ma and pa at the head and young ones of varying competency.  They worked and hunted cooperatively. They were consummately social but capable of prolonged solo journeys.

It made sense that the Middle East, if not North Africa, was where this all started because that would have been the region of first contact. But because of their natural affinity, wolves and humans got together wherever they met.  Some of the resultant “dogwolves”—my phrase for doglike wolves or wolves that act like dogs—created lineages that survived a while then fizzled out; others endured.

I identified several hotspots for early dogs across Eurasia and a group of humans that at least according to genetic evidence might have made its way through the cold of the last Ice Age from the Persian Gulf oasis, then a fertile land, to the Altai Mountains of Central Asia, a region that also hosts the headwaters of the Amur River, still famous for its wildlife.  This group’s dogwolves mixed and matched with others along the way, especially the big mountain dogs of the Caucasus.  This group of hunters and foragers gathered in the Altai around 40,000 years ago and from there ultimately took the New World.* They also went with their dogs, I calculated, south and east into China, Korea, and Japan and west again with their giant dogs, now mastiffs.

I based that conclusion in part on the types of dogs found in the New World. It made more sense that the possibility for the phenotype was present even if the phenotype itself was not manifest than that it was introduced later. 

It was with some interest, then, that I read in PLoS One for July 28, 2011, about a 33,000 year old ‘incipient” dog from the Altai Mountains—that is, an early attempt at a dog that went nowhere. The finding was immediately challenged, and the fossil dismissed as a wolf, even if a strange one. So a new team of researchers redid the work in Robert K. Wayne’s evolutionary biology lab at UCLA and on March 7, 2013, published an article in PLoS One confirming that the 33,000 year-old-fossil is that of a primitive dog.

Writing for their colleagues from Russia, Spain, and the U.S., Anna S. Druzhkova of the Siberian Branch of the Russian Academy of Sciences and Olaf Thalmann of Turku University, Finland, state that when compared with other canids, the Altai dog, as it is known, shows closest affinities with New World dogs and modern dog breeds, ranging from Newfoundlands to Chinese Cresteds and including cocker spaniels, Tibetan mastiffs, and Siberian huskies.   

Equally interesting from my perspective, the Altai dog does not appear to have been related closely to wolves in its immediate vicinity or to modern wolves.  It came to the Altai from elsewhere, probably with people.

The researchers emphasize that there is uncertainty in their findings because they are based on a single region of mitochondrial DNA. But from my standpoint, the work provides one bit of evidence that’s I’ve not been barking up the wrong tree—and that seems worth noting.

 

 

Notes:

*Ted Goebel et al., “The Late Pleistocene Dispersal of Modern Humans to the Americas,” Science, March 14, 2008. Connie J. Kolman et al., “Mitochondrial DNA Analysis of Mongolian Populations and Implications for the Origin of New World Founders,” Genetics, April 1996.

Good Dog: Studies & Research
At Long Last Love
An interview with Jeffrey Masson

This is one of the first interviews (if not the very first interview) ever to appear in the pages of Bark. It was originally published in Bark’s third issue in fall 1997—back when Bark was still printed in black-and-white on newsprint—when Jeffrey Masson first released his book Dogs Never Lie About Love.

On the day of our interview, Jeffrey Masson’s lovely Berkeley home was a bustle of activity, with friends and family popping in and out, the baby, the three dogs and the cats. There had been a wedding only days earlier and Masson was preparing for a major book tour. We were very grateful that he’d found time to squeeze us in. As we settled in for our talk, the phone rang——his agent calling to talk about Masson’s appearance on Dateline the previous night. “I’ve got to go, I’m being interviewed by the Berkeley Bark,” Masson said, cutting short talk of national TV to give this interview.

Your title is Dogs Never Lie About Love. It reminds me of a Fats Waller song, “Be sure it’s true when you say I love you, it’s a sin to tell a lie.” To me it has always been an odd lyric, because how do you lie about love, or how do you not lie about love——our emotions are so complex. What exactly do you mean by this title?

It was suggested to me by my trainer, a wonderful guy at Guide Dogs for the Blind——Mike Delosi. He said you’re gonna laugh, but I just thought of the best title your book——Dogs Never Lie About Love. Laugh!, it’s perfect! And it really is the thesis of the book, that dogs are incapable of any kid of deceit when it comes to their emotions. They don’t hide them from others and don’t hide them from themselves. We sometimes don’t know what we’re thinking and feeling and certainly often attempt to prevent others from knowing what we’re feeling. Nobody doubts this. But dogs are so upfront about their feelings. They can’t, they just can’t...

They don’t mind being the fool.

That’s right. This is who they are. They don’t think, “If I’m showing my joie de vivre they’ll think I’m unsophisticated and naive. What they’re feeling is who they are. And I think that love is really the master emotion for dogs. They really seem to have an endless supply, an endless capacity to love that just astonishes me.

You say in your introduction that you were originally attracted to the observation of wild animals because you felt that somehow the domestic dog was contaminated by association with humans. Have you changed your mind about this?

Well, I don’t really know. It’s fascinating to me that dogs feel as much as they feel and that we can read them so easily. So the question is, why can we read dogs so easily, why are they so transparent to us and we to them? There’s no other animal like that. We don’t know what a bear is feeling. You know when they’re angry, but you don’t know when they’re sad and disappointed and nostalgic and homesick and all these things that we have in common with dogs. So the question arises, did canines learn it from us or is it just some miracle of parallelism. Or is it that all animals share these things and we just can’t read them. I haven’t discovered the answer to that. I suspect one could. If you were to live with wolves long enough you might be able to say it’s clear that wolves feel the same things that dogs feel, therefore they didn’t get it from us.

Didn’t some of your studies of the wild animals, for instance elephants in the zoo, show that they have a rapport with their people?

Not like dogs, possibly, but not even cats. I have two cats here and I love them but they really don’t have that same intimate constant interaction with us that dogs have. Horses don’t, parrots don’t, no animal does.

It begs the question … Was is there from the beginning, and that’s why we got together with them?

That is an interesting question. But it’d be awfully hard to answer. I think if you knew enough about wolves, if we discovered that wolves show the same emotions with other wolves, then we could say it’s the nature of the beast——it’s not us. But I suspect that it is us. Because dogs are so eager to please us and understand us. When I first got my three dogs, I thought——I can’t do this. It’s just too much, three big dogs walking around Berkeley, how am I going to get them out of the car and into this park without putting each one on a leash. I can’t do it. And lo and behold it was really easy after a while. They figured out what I want from them and they give it to me. It took time, and I didn’t train them. It’s just that they watched me and observed me long enough to figure that “Oh, he want us to do this! Ok, I get it, I can do that.” And that’s amazing! Cats don’t do that, they may know what you want, they just don’t care.

In fact, some part of them may know what you want and do …

...the opposite. And a dog will never do that. Very rarely will a dog do what he knows you don’t want him to do. Very rarely.

My dog is very willful. If he doesn’t want to do what I want him to do he won’t look at me. He pretends he can’t hear me.

Hysterical deafness in dogs.

I find your last book (When Elephants Weep) and this book almost radical because I think it’s been anathema for intellectuals to discuss emotional states in animals. Even though anyone who has ever lived with animals or worked with them in a lab could observe that.

The people who work with them in labs have a vested interest in denying that they feel. Because if you say that you think that a dog can feel pain and can suffer as much, if not more than we can, then what kind of person inflicts that pain? It’s hard. The honest ones will say yes, that animals do suffer but animal testing helps mankind. OK, I don’t agree, but you can live with that. What I don’t like is when they say animals don’t feel anything. I don’t see how they say that about a dog. I mean maybe with a rat, I don’t believe if for a minute, but I can understand someone saying he can’t see emotion in rats.

I think it’s easy for people to denigrate their own observations because of what experts say.

You have to look at what vested interest experts have. In the segment of Dateline I just did they had to have a critic talk about my book so they get Dr. Hart who’s the head of the behavioral clinic at UC Davis School of Veterinary Medicine, and he said, “Masson is totally wrong——everything a dog does is pure instinct.” And that is the cliché——that’s what they were taught and it’s very hard to get them to move away from that. You could say that about every human emotion. If a mother saves a child who’s drowning——is that instinct or love?

I expect that there are people who have those theories about humans.

I’m sure that there are. But most people who would say that about a dog would not say it about a human being. Why would a dog have an instinct to save a human being anyway? It can hardly be instinct, and there are literally thousands of stories of dogs that have saved people.

I like something you said in your introduction. You asked, “Why is a lab scientist a more reliable observer?” Most people take it for granted that scientific method is objective and that the scientist must necessarily be an objective observer.

We’ve been taught that. They say, well you’re telling us a story and that’s just an anecdote. Anecdotal evidence. What do they think they have when they’re in the laboratory? It’s just another story. And if you have enough of them, if you’ve collected a thousand similar stories, isn’t that data?

You go over how you selected your dogs and what you were looking for and I was struck that all three were females. Did that make a difference to you?

Well, my publisher was very annoyed about that. He wanted me to have a male dog. And it’s true, it would have been interesting to compare. It just so happened that all three of the ones I wanted turned out to be females. So I’m sorry, I’d like to know whether, for example, males are more aggressive than females. These three dogs are just not aggressive. They have never gotten into a fight with each other or another dog. They’re not perfect dogs by any means, little Simi gives this horrible Grrr to every dog she meets. But she’s never actually gotten into a fight, and I wonder if she were a he, would he get into fights?

They’re all so individual.

That’s true too. Certainly there are male dogs that we encounter that would never fight. And there are certain females that we meet that would. But no dog has ever fought with mine. My theory is that males will not fight with females unless they’re trained to fight. But if we’re just walking around and they do something offensive, males will forgive it right away. And females don’t seem to fight much between themselves.

My dog has a lot of propriety and he expects other dogs to be … dignified. He gives females a lot of slack, but not males.

I think that dogs can be very dignified and there’s a difference in a dog who is not and one who is. It’s an interesting quality. In a lot of the working dogs, I have the sense that they feel that there’s a way to do things and an improper way. I was hoping to get a Border Collie for that reason, but I also hear that they’re hyper. They’ve got to be doing stuff. I’m spending three, four hours a day out with my dogs, so they get plenty of things to do. I didn’t think I would spend quite that much time, but with a little baby it’s fun. I like being out anyway and since it turns out to be my research …

What a nice life. Are these your first dogs in a while?

The last dog I had was a long time ago, about six years ago. I had moved into someone’s house who left the dog behind. An old German Shepherd. And I really bonded with him, I was amazed, but it was in the last year of his life. And before that, in my previous marriage, we had a Standard Poodle for 15 years——I loved that dog! And before that it was as a child. So there haven’t been that many dogs in my life.

I haven’t really had a dog since childhood. My dog now, I feel very conscious of him and have a close bond. And I think that he’s taught me a great deal about human nature, too. I wonder what your dogs have taught you.

For me, that’s how the book came to have this thesis. I really do believe that dogs feel more intensely, more purely, more passionately with less ambivalence than I do. I can’t speak for you, or anyone else, but for me they definitely do. And I want to learn from them, and I do learn from them. How to live in the moment——dogs are very, very good at that. They’re really like little gurus. All these gurus claim to live in the moment, but don’t really do it. Dogs do it. They really live in the moment, and they don’t compare things. I still have a bad habit that I picked up from my parents of comparing one thing to another, one place to another, one person to another. Dogs never do that. I don’t know if you’ve ever been to the landfill in Berkeley, that tacky little beach opposite where we always go. But it has the world’s ugliest beach! And I took my parents there once and they said, “Jeff how can you even walk on this beach, remember when we were in the South of France and Cannes and do you remember the Italian Riviera?” And I said yeah, this is really tacky …. My dogs——they love it! They’ve been to the most beautiful beaches in the world up in Oregon and here … they don’t care! For them, it’s the moment that counts, they’re with the person they love, they’re chasing sticks, they’re jumping in the water, they’re perfectly happy——they never make those comparisons. So, those are the things I’ve learned from them. Also, I haven’t learned it, but they’re very good at forgiving. That, I’m not so sure I want to learn, but they can do it. I mean you can, I never have, but people hit dogs and a minute later the dog will lick their hand, I mean a minute later! I guess some dogs less than others, some dogs probably will remember and hold a grudge. But most dogs don’t hold grudges, they really don’t.

There is an interesting story in your book about a police dog stopping his master who’s unjustly beating a guy.

It’s a Vicki Hearne story and I believe it. It’s utterly fascinating! I wish I had observed it, I’d love to know what was going through that dog’s mind.

That’s a very complex thing!

Very complex. If that’s true it shows an extraordinary … if it’s true you don’t see it very often, that’s for sure. I asked the police here, “Does a dog ever stop a thief or a shoplifter?” No, they wouldn’t do that, they don’t care, they don’t share our values. But obviously this person had overstepped some canine value. I think it’s an utterly fascinating concept. I’ve never observed that. That’s Vicki Hearne’s. She’s very unsentimental, that was one of the few sentimental stories in her book. She’s a big trainer and I’ve seen a lot of training now and I’m not into it, it’s not my thing.

I believe she’s written about circus animal training. I just saw a film, Fast, Cheap and Out of Control, which featured a lion trainer, whose attitude toward the lions was adversarial, one of fear ….

Never turn your back, show who’s boss. A lot of dog training is like that too.

The interesting thing about the film is that the lion trainer had a protégé whose attitude was not adversarial, she built a rapport with the lions. The elder trainer had a very grudging respect for his young apprentice——well, it seems to work but someday she’s going to be sorry.

Right, it’s that way with dog training, also. I went to visit one of the legends of training, a guy named Sapir Weiss, have you heard of him? He’s an Israeli paratrooper and he’s trained dogs to carry dynamite. And he was amazing, I have to admit. I walked in and we started arguing right away. He doesn’t believe in emotion, nothing——it’s all training, it’s all conditioning. He says, “It’s all about who’s boss, and I’m the big boss and they know it and I have a way of letting them know this right away.” And I said I didn’t believe it. He said, “You know, I’ll prove it to you.” He said, “Are these three dogs very attached to you? I’m going to walk with them and you call them back to you and I guarantee you they won’t come.” I said no way. And they walked right by me and I called “Sasha, Simi, Rani,” and they looked at me like, “I’m sorry I can’t come”——they wouldn’t budge. I said, “What is this, is it a magic act?” He said, “I convey I’m the boss and they know it, I know how to communicate that to dogs. You don’t hear a single dog in my kennel of ninety dogs barking, do you? That’s because I let them know I won’t tolerate it.” It’s very impressive—I still don’t like it …. He had a dog, a fabulous Schutzhund but the dog seemed miserable, he never goes out, does everything Sapir says and looks at him in constant apprehension.

It’s hard to know how the dog feels about that, but for me, I don’t want to have that kind of relationship.

That’s a good point. I can’t say, but in my opinion, the dog would rather have a more equal kind of relationship. I can’t answer that. But I don’t want that with them, and I’m not going to train them to go blow up trains with dynamite so …. On the other hand I also went through Ian Dunbar’s training with the puppies and that didn’t work so well. I finally decided that the best training was no training—you hang out long enough with the dogs and they figure out what you want and they do it. My dogs come, they stop for traffic, they do the important things. I taught them the command “Leave It” when they’re eating horrible garbage. They do that.

My dog hasn’t got that one down.

Well, when I tell them stay they’re not going to do it, and I’m sure I could train them to do that but it would mean breaking their will to some extent, and I’m just not prepared to do that.

Yes, I don’t relish that authoritarian relationship, consequently my dog is not the perfect obedient dog.

But I think it allows them to be more of who they are. This is also the problem with guide dogs for the blind, I mean I’m very impressed with what they do and obviously it’s wonderful work and it’s wonderful for the blind people, I wonder how wonderful it is for the dog. You know this is not something the dogs would choose to do on their own, given the choice.

Well, you know I think there are some individual dogs who must want to.

Maybe, they take pride in it, yeah.

Like herding and working dogs, a lot of them really love to work and they do take pride, and that’s a big part of life.

But it’s not all of life … pleasure is also part. They’re not big on pleasure at Guide Dogs for the Blind. The dogs have a certain amount of time when they play but my dogs basically play all day. They don’t work and I think it makes them very happy. It’s very hard to judge. Who’s to say who’s a happier dog.

Your dogs have a good life.

They have a very good life.

What say you about leashes?

Berkeley must be the best city in the world to have a dog because we don’t have a leash law on the street. The police don’t always know it but I went to City Hall and got a little piece of paper with the ordinance that says if a dog is obedience trained and is under voice control then it shall be deemed to be upon a leash. The few times that the police have stopped me, I live across the street from the Berkeley Police Station, I’ve just shown it to them and they’ve been very nice about it. Most of the time I don’t get stopped, and I walk around Berkeley with my three dogs off leash, and I really like that. It’s just different, it really is different. It makes me feel that we are more equal. They can stop and sniff things, they can deviate a little bit. I mean, they still basically go where I want to go, it’s not equal in that way, but they’re free and I really like it.

On the other hand there is a leash law in the parks.

Yes there is, and I just don’t obey it. If a ranger tells me to leash them, I do. Most people don’t care. When we go to Inspiration Point for walks, most dogs are off-leash and people are very happy about it. But, at least once a walk, somebody will come to me and say, “Those dogs are supposed to be on a leash!” And the dogs aren’t doing anything, and I ask them, “Can you explain to me how they’re bothering you?” “It’s a law!” “Well you’re right, but they don’t seem to be harming anybody, and they’re getting so much pleasure, do you really want me to leash them? “Yes, I do!” You always get a few, but for research it was interesting to hear that.

Do you ever take your dogs on leash? Because it’s a very different experience.

I really don’t like to do it. Sometimes outside of Berkeley you have to. We went on a camping trip and they were very unpleasant sometimes if the dogs were off-leash so we took them on-leash in the camping grounds. I just hate it!

I think that dogs are more aggressive on-leash.

Definitely.

I’ve read lots of training books, and there are many different theories. Some feel that the dogs become more territorial on your behalf on lead.

I don’t understand it. Another thing I don’t get … my dogs go completely nuts when they’re in the car and we pass a car with another dog or pass another dog on the street. All three of them. Walking down the street they pay no attention.

Not even when the other dog is behind a fence?

Behind a fence, yes. Behind the fence they hate.

I once saw a baseball game when the pitcher hit the batter with a fast ball. The batter stormed the pitcher’s mound in an attitude of “Let me at ‘em.” But both players kept their arms at their sides, shoulders back. Not until teammates came to restrain them did they really start flailing. When they were safely restrained from hurting each other, the killer came out. I see this behavior in dogs behind fences. They can engage in a little aggression because they really can’t do anything.

Maybe you’re right. If they pass each other on the street they could hurt each other, but they can’t in the car or behind a fence. Interesting. But the car thing, I don’t like it and I’ve begged them to stop, but it doesn’t do the slightest good. Not the slightest good.

You were initially not interested in studying dogs—they were perhaps contaminated by their association with humans. Have you also found that you see the wildness in dogs?

Oh yes! That’s the miracle to me, that we are living on intimate terms with a wild animal. It really is, it’s a wolf. There not that much difference between wolves and dogs, and it’s a very humbling experience. Suddenly your dog does something or howls and you feel my God, this is a wild animal and it has accepted me and we are living together! And no other animal gives you that … well cats a bit too, because they really are tigers. But dogs even more, and it’s just such a miracle to me. I can’t get over it.

News: Guest Posts
Behavioral Differences Between Dogs and Wolves

Dogs and wolves share a similar genetic profile. So why are their behaviors so different?

The reasons aren’t clearly understood. In a recent paper in the journal Ethology , evolutionary biologist Kathryn Lord's doctoral research (University of Massachusetts, Amherst) suggests differences in later behaviors might be related to the pups' earliest sensory experiences during the critical period of socialization, the brief period when a puppy's exposure to novel things results in long-term familiarity.

Lord's research demonstrated that dog and wolf pups acquire their senses at the same time:

·     Hearing:  Onset 19 days, reliable by 28 days

·     Seeing: Onset 26 days, reliable by 42 days

·     Smelling: Reliable by 14 days (onset likely earlier)

What's different?

·     Dog pups wait until 28 days to explore their environment when all senses are operational.

·     Wolf pups begin exploring the world at 14 days, relying solely on scent, when they are still blind and deaf.

Although wolves are tolerant of humans and things they were introduced to during the critical period, they don't generalize that familiarity to other people or novel things when they mature. Dogs on the other hand, can generalize, and if properly socialized are not spooked by novel sounds and sights.

Why do mature dogs and wolves behave so differently?  Lord's conclusion is that at the gene level, the difference may be when the gene is switched on, not the gene itself.

What could that mean? Research has shown that the brain is capable or rewiring itself in dramatic ways. Early loss of a sense affects brain development. For instance, even though the developing auditory cortex of a profoundly deaf infant is not exposed to sound stimuli, it doesn't atrophy due to lack of use. Rather it adapts and takes on processing tasks of other senses including sight and touch. Perhaps wolves see the world in smell, and dogs see it a lot more like we do.

Click here to read the paper, A Comparison of the Sensory Development of Wolves (Canis lupus lupus) and Dogs (Canis lupus familiaris), by Kathryn Lord, Ethology, February, 2013.

 

 

Good Dog: Studies & Research
For Dogs, What We Do is More Important Than What We Say
Research shows that for dogs, actions count

My suspicions were confirmed on December 26, 2002, while at the Metreon Theater in San Francisco. As the youngest in the family, my job was to wait in line for tickets, and, knowing this, I went prepared with a scientific article titled, “Do dogs respond to play signals given by humans?” The research, lead by Nicola Rooney at the Anthrozoology Institute in Southampton, UK, featured 21 dog/owner pairs playing—or at least, attempting to play. In what could surely have been billed as a comedy, owners patted the floor, barked, bowed, shuffled their feet, slapped their thighs, crawled on all fours—anything to get their dogs to romp with them.

The researchers videotaped the sessions and meticulously catalogued, recorded and identified common actions used by owners to solicit play. They then tested to see which signals actually worked. As expected, bowing in a human version of a dog play-bow, as well as lunging while verbally encouraging the dog, usually elicited play. Other gestures, such as tickling the dog as though she were a human infant, or stamping one’s feet as though dislodging last week’s dried mud from hiking boots, just earned blank looks. And surprisingly, patting the floor and clapping were less than 50 percent successful. What’s more, while barking at, kissing or picking up the little pooches probably brought on laughs from the researchers, most dogs failed to find these actions amusing.

As interesting as these findings were, the real message—one that stayed with me—was what came next. Upon analyzing the data, the researchers found that although some actions tended to instigate play while others resulted in silent stares, the frequency with which the owners used the signals was unrelated to their success. In other words, owners tended to use unsuccessful gestures even after they were demonstrated not to work. And there I had it, scientific proof: Dogs are smarter than humans. Well, at least in some ways. You see, dogs are champions at trial-and-error learning. They have all day to try things out and see what works.

For instance, want to play fetch when your people aren’t interested? Grab a tennis ball and drop it at your human’s feet, and then bark until he finally picks it up and tosses it. Getting the silent treatment? Bark longer and louder—you’ll eventually get a response. Or, choose the right time, like when your human’s on the phone; that’s when they’ll do anything to get you to shut up.

While dogs are masters of this style of learning, we humans are hindered by our much-vaunted cognitive abilities. Armed with the wonderful capacity to observe and imitate, we copy the behaviors we see, whether they work or not. Clouded by our preconceptions of the techniques we’re supposed to use, we forget to stop and evaluate whether our actions or methods actually work.

This might seem like fun and games when it’s just us dancing around trying to get our dogs to play. At worst, when our pooch refuses to romp, we attribute it to her not being in the mood. But when it comes to something more important, like coming when called or sitting on command, a dog’s failure to perform can result in her being labeled “stubborn” or “stupid.” Because what else could it be?

Well, according to a series of research studies by Daniel Mills (veterinarian and researcher in Behavioural Studies and Animal Welfare at the UK’s University of Lincoln), as with play signals, much poor performance could be attributed to dogs’ inability to decipher our signals. It turns out that even if our dog responds to our commands some of the time, she may not know what they mean as well as we think she does.

According to Mills, a number of factors determine how well our dogs perceive the message we intend to give. One is whether the signal is verbal or visual. While we humans are used to communicating by talking, Mills’ research indicates that this may not be the best mode of communication with dogs. In an experiment to test which signal type takes precedence, Mills and his colleagues trained dogs to respond to a verbal right and left cue as well as a visual pointing cue for the same behaviors. To guard against bias that could be created by the order of teaching, half of the dogs were initially trained using verbal cues and the other half, using visual cues

Then they tested the dogs by placing a treat-holding container on either side of the subject—one box on the right and one on the left. When they gave the “left” cue, the dog got the food reward if she ran to the box on the left. If she ran to the wrong box, she got no reward. Once dogs consistently responded correctly to verbal and visual cues alone, the cues were given together, with a twist. The researchers gave a verbal signal for one direction and a visual signal for the other to see which one the dogs would follow. For anyone whose dog competes seriously in agility, the results were a no-brainer: The dogs consistently followed the visual pointing cue and ignored the verbal cue. This dynamic plays out on every agility course—a dog will usually go where her handler’s body is pointing rather than where the handler might be verbally trying to send her.

This bias toward the visual as opposed to the verbal can pose problems for dogs even in everyday life, says Mills, “This simple example emphasizes that when training dogs, we have to realize that dogs may be reading signals we’re not aware of.” So when your voice tells the dog to do one thing but your body tells her to another, she’s not being stubborn—she may just be reading a different message than the one you think you’re sending.

Even when we’re purposefully sending visual commands to our dogs, such as in the obedience trial ring or field trials or other long-distance work, there’s more to the signal than we might think. Says Mills, “In a similar study, we looked at the dog’s response to different visual right-and-left cues. We compared eye movement and head movement to the right or left with pointing right or left, but keeping the eyes and head looking forward.” Using six dogs, they found that dogs found the hidden food source faster when the two signals were presented together which, Mills says, suggests that “Dogs are taking in the whole picture of what’s going on.” That is, they don’t look at our hands or our head, they look at our entire body. As a result, if all signals are not consistent, dog can become confused.

Do these studies mean we should scrap verbal commands altogether and focus on the visual signals? Obviously, dogs can learn verbal commands, because we use them all the time and some dogs respond correctly on a regular basis. But perhaps even those who respond don’t know the cues as well as we think. Mills and his colleagues performed a series of studies to test this, too. First, they tested slight variations in the commands to see if dogs recognized them as the same words. They taught dogs to stand and stay, and then, from five feet away, the trainer gave either a “come” command or a “sit” command.

Once the dogs were reliable about responding correctly, the researchers changed the command words slightly. In place of “sit,” they used “chit,” “sat” and “sik,” and in place of “come,” they used “tum,” “keem” and “kufe.” The results? In general, dogs did not respond as well to the similar-sounding words; or, taken from another viewpoint, they were able to recognize that the similar-sounding words were not the same as the commands they had learned. This sounds like no big deal, but, says Mills, “From a practical point of view, due to slight differences in how handlers pronounce words, obedient response to one handler’s commands won’t necessarily transfer to another unless the phonemic characteristics are mimicked.”

You might think you could get around this by tape-recording the command and just playing it back, but Mills found that dogs don’t respond to tape-recordings as though they were a real-time human voice. In yet another experiment, a “come” or “sit” command was given in one of four conditions: from a person sitting in a chair; from the same person wearing sunglasses to prevent visual cues; and both conditions, but the command issuing from a tape recorder behind the person. Says Mills, “Dogs made many more errors when the tape recorder was used.”

Such errors could be attributed to the dogs distinguishing a difference between the tape-recorded and live voice command, but another hypothesis is that dogs also rely on lip movement or some other indication that the human is speaking to them. In fact, in a fifth variation, the handler uttered the “come” or “sit” cue while looking away from the dogs, and they again made many errors, indicating that orientation of the handler is important.

By now, it should be clear: Be aware of visual signals, as they may override the verbal commands. Make sure all of your signals mean the same thing, or your message may look more like a dubbed version of Godzilla than a clear-cut cue. When you do use verbal cues, make sure everyone says them exactly the same way, or train your dog that slight variations mean the same thing. And if you plan on your dog responding correctly to your verbal commands when you’re out of sight or facing away, you’ll have to specifically train him to do so.

And that’s not the end of it. Turns out that the emotional content of your message is important too. Mills’ group trained dogs to reliably come or sit when a handler was standing five feet away behind a screen. Then they tested to see how dogs responded to different emotional contents. The commands were uttered in a neutral tone; a happy tone, with the inflection ascending; an angry version, with the tone descending; and a gloomy version, in which the handler sighed first. Dogs responded more predictably when the tone was positive, but when the command was said in an angry or gloomy manner, there was more variation in their responses.

So what’s the take-home message? The one your pooch is dying for you to learn? Here it is: Perhaps when your dog gives you a blank stare after you utter a command you think he knows, she has a good reason. Because when communicating with our pets, it’s not just what we say, it’s how we say it and whether our visual and verbal cues are sending the same message. Once we become more aware of the signals we send to our dogs and how they perceive them, we can cut down the number of everyday frustrations and open clearer lines of communication with our four-legged friends.

 

 

Dog's Life: Lifestyle
Research About Dogs Responses to Human Emotion
Could this study be improved?

In the recent study “Can domestic dogs (Canis familiaris) use referential emotional expressions to locate hidden food?”, researchers investigated whether dogs have the ability to locate hidden food based on the emotions shown by people’s facial expressions. It’s a fascinating question, and I was eager to learn what the experiment revealed.

Unfortunately, I had concerns related to the methods, and the result was that I found that the experiment lacked the strength it could otherwise have had. When I read scientific papers, I pay careful attention to the methods because unless I fully grasp the details of the experimental design, it is impossible to draw conclusions about the meaning of the study. Often, flaws in the methodology result in studies whose conclusions should not be accepted without further evidence from better experiments.

In the study I just read, people picked up two boxes, one at a time, and made facial expressions of happiness or disgust or they kept their expression neutral. Then, the dog was given a choice about which box to go to. (The dogs had been trained to understand that these boxes could contain food.) The idea was to see if the dogs would choose the box that was associated with happiness rather than the box associated with disgust or with a neutral expression. Overall, there was an effect of the human expression on the choices made, though many individual dogs made choices throughout the trials that were no better than chance.

The location of the testing was not always the same. Some of the dogs were tested indoors, and some were tested outdoors. Four breeds of dogs (Labs, Goldens, Border Collies, and German Shepherds) were pet dogs who lived with families in homes, and were tested indoors, but the Huskies lived in a facility for racing dogs and were tested outdoors.  The investigators did in fact find a difference between dogs tested in these two conditions, but there is no way to tell if this is because of the breed, because they were tested outdoors, or because of their different social situation, which the experimenters acknowledge. With more than one variable present, determining which variable matters is a challenge.

Since the whole point of the experiment is to test the effect of human facial expressions, then the facial expression should be the only variable in the experiment. Unfortunately, in this study, other variables besides the ones already mentioned were not held constant. The “happy” box contained sausage, the “neutral” box contained wood shavings, and the “disgust” box had garlic in it. The neutral expression had no accompanying vocalization, but both the happy and the disgusted expression did. If the dogs did respond differently to any of these conditions, it’s hard to know whether or not the contents of the box, the presence or absence of a vocalization, or the people’s expressions (or some combination) was the cause.

In a better-designed experiment, all the boxes would contain exactly the same item, and the other differences not being tested would be eliminated as well. The researchers did a series of tests to determine if the dogs were choosing boxes based on smell alone, but only in the outdoor condition with the Huskies. (They found that these dogs were not using smell.)

To be fair, the researchers spend quite a bit of space in their discussion explaining how this experiment could have been done better in a cleaner way, scientifically speaking. I agree with their analysis that improvements could be made to the design that would add strength to their conclusions. I would have preferred for them to conduct their experiments with the improved designs before publishing, though I understand that it is immensely challenging to explore cleanly the role of human emotion in influencing dog behavior.

There are so many variables with pet dogs because of the different amounts and types of experience they have in their lives, and not only are they impossible to control for. Even if you could control many factors by raising dogs in labs and controlling their environment, then you introduce the problem of dogs who are not in the “pet dog” environment. I’m not saying that an experiment into these issues can ever be perfect, but I do think that this study could be improved upon.

Dog's Life: Lifestyle
Playing with Our Pups
Dog Cognition Lab is looking for play videos

A couple years ago, I brought my two Shelties to the Harvard Canine Cognition Lab to participate in a study on dogs’ understanding of human gestures.  Boston isn’t exactly close, but I was happy to drive the three hours to check out the research being done on the canine brain.

As pets become a bigger part of our lives, universities are getting more funding to understand what going on in our dogs’ heads.  Schools with canine cognition programs include Harvard, Barnard, Duke, University of Florida, Eckerd, and University of Kentucky.

Canine cognition labs are always looking for dogs to participate in their research, but for those not willing to travel, now you can participate in a study without leaving the comfort of home.

The Dog Cognition Lab at Barnard College in New York is currently looking at play between canines and humans.  To participate you need to complete a short survey and upload a 30-60 second video of you and your dog playing.  They’re interested in seeing how people typically play with their pets and are not looking for any specific style.

Past research at Barnard has included studying olfactory discrimination, anthropomorphisms (such as the concept of “fairness” and the “guilty look”), use of attention and play signals in social play, and communication between dogs.

I think the human-canine play study will be particularly interesting since the videos will allow people and dogs around the world to participate.  And it’s a cool way to bring animal lovers together in the name of scientific research… not to mention while having fun playing with our dogs!

Good Dog: Studies & Research
Do Dogs Understand Our Words?
Say What?

“This is not your food! Don’t even think about eating it. This … is … not … your … food.” What do our words mean to dogs? Not that I’m about to stop speaking to dogs anytime soon, but I do wonder what my daily utterances signify to Millie, Piper, Upton and Finnegan, the dogs I converse with on a regular basis. Do I sound like a cross between Charlie Brown’s teacher and Gary Larson’s “What Dogs Hear” cartoon? Are we on the same page, or even in the same book?

I set out on a quest to explore dogs and their understanding of human language. What do we think dogs understand? A lot, according to a study by Péter Pongrácz and his colleagues at the Family Dog Project in Budapest. Thirty-seven owners provided a list of 430 different utterances that they thought their dogs knew, with each owner providing an average of 30 phrases.

Enter Rico, Chaser, Sofia, Bailey, Paddy and Betsy, companion dogs celebrated for their panache for human language. The news media hails them as “super smart,” and after meeting Chaser, astrophysicist Neil deGrasse Tyson exclaimed, “Who would have thought that animals are capable of this much display of intellect?”

So what are these dogs doing with words?

Objects
Dogs can learn the names of many, many, many different objects. Julia Fischer, group leader at the German Primate Center’s Cognitive Ethology Lab, heard that a Border Collie named Rico knew the names of 70 individual objects, and she wanted to know how Rico mapped specific human words to particular objects. “I contacted the owners, and they let us visit their home and start a study of Rico,” explains Fischer. This culminated in 2004 with an article in Science, reporting that Rico knew the names of over 200 different objects.

Seven years later, Chaser, a Border Collie in South Carolina, took the gold medal when Alliston Reid and John Pilley of Wofford College reported that Chaser knew the distinct names of 1,022 objects — more than 800 cloth animals, 116 balls, 26 Frisbees and 100 plastic items. Chaser knows that “Uncle Fuzz” is different from “Wise Owl,” who is certainly different from “Merlin.” This is not merely a story about Border Collies, however. Researchers recently related that Bailey, a 12-year-old Yorkshire Terrier, knows the names of about 120 toys.

Chaser and Rico also win praise for their ability to learn and retain the names of new objects. When presented with a group of toys, all of which were familiar except one, the dogs could retrieve the unknown toy when asked to fetch using an unfamiliar word. In essence, the dogs were pairing a novel object with an unfamiliar name after a single association and then remembering the name of that new object in subsequent trials. In children, this is called “fast mapping,” and it was thought to be uniquely human. Pilley notes, “This research shows that this understanding occurs on a single trial. However, Chaser needed addition rehearsal in order to transfer this understanding or learning into long-term memory.”

Actions
But life is not only about knowing the names of one’s stuffies and Frisbees. Humans often use verbs such as come, sit, down and off to get dogs to alter their behavior. After controlling for outside contextual cues, researchers found that dogs could still understand that specific words map to specific physical actions. Chaser showed an incredible amount of flexibility with actions — performing “take,” “paw” and “nose” toward different objects.

“That’s just training,” you might say, but this suggests that some dogs show a cognitively advanced skill where actions are understood as independent from objects. Reid and Pilley found that Chaser does not interpret “fetch sock” as one single word, like “fetchsock.” Instead, she can perform a number of different actions flexibly toward a number of different objects. Daniela Ramos, a veterinary behaviorist in São Paulo, discovered that a mutt named Sofia could also differentiate object names from action commands, suggesting these dogs attend to the individual meaning of each word.

Categories
Chaser puts the icing on the cake when she assigns objects to different categories based on their physical properties; some are “toys,” others are “Frisbees” and, of course, there are “balls.” Chaser takes her cue from Alex, Irene Pepperberg’s African Grey Parrot, who also learned categories like color, shape and material, and differentiated which trait was the same or different.

This all seems quite extraordinary, but nothing comes free of controversy. Do dogs like Chaser and Sofia use and understand language the same way humans do, or are they merely welltrained? For example, some researchers are not certain that dogs actually “fast map”; dogs might be doing something that simply looks like “fast mapping” from the outside. Regardless, it does seem as though these dogs have a conception of objects and actions. Patricia McConnell, PhD, Certified Applied Animal Behaviorist and beloved Bark columnist, agrees. “Understanding requires that we share the same reference — that we have the same construct of an object or an action. For some dogs, it seems like they do.” Pilley concurs. “When an object, such as a toy, is held before Chaser and a verbal label is given to that object, Chaser understands that the verbal label refers to that object.”

In her book Inside of a Dog, Alexandra Horowitz reminds us that even if these are the only dogs in the world capable of using words this way, it allows us to see that a “dog’s cognitive equipment is good enough to understand language in the right context.” This body of research indicates what is possible, not necessarily what most dogs do every day.

Who Are You Living With?
Whether you have a Chaser or a Rico in your home might largely depend on you. As Fischer explains, “A dog’s use of human language depends very much on the willingness of the owner to establish a verbal relationship, to establish links between words and particular meanings.” Fischer is referring to motivation in both the human and the dog. Ramos and her colleagues trained and tested Sofia two to three times a day, three to six times a week. When Pilley, who doubles as researcher and Chaser’s owner, began training Chaser to identify objects at five months of age, Pilley repeated object names 20 to 40 times each session to make sure she got it.

Like Rocky Balboa preparing for his climactic showdown, these dogs are highly motivated. Fischer notes, “Rico was eager and hard working. You’d have to tell him, ‘That’s enough. Get something to drink. Take a rest.’” Chaser is similar, says Pilley. “She has two states—highly, highly active and recuperating and resting.”

Denise Fenzi, a professional dog trainer from Woodside, Calif., who specializes in a variety of dog sports, reminds us that this type of motivation is not necessarily the norm. “Not all dogs share this attention to words. Even in my dogs [all of whom are the same breed], there is a huge difference in ability to verbally process. I didn’t train them differently. It’s just easier for one to quickly get words.”

Training Matters
The way dogs learn words might be the biggest piece of the puzzle. McConnell finds, “Word learning might depend upon how words are first introduced. The guardians who explicitly differentiate words, teaching, ‘Get your Greenie! Get your ball,’ often have the dogs with big vocabularies. On the other hand, my own dog Willie was given verbal cues for years that stood for actions rather than objects. When I tried to teach him that words could refer to objects he was completely confused.”

What dogs are able to do with language could also be explained by their tutelage. If dogs don’t learn to attach a variety of different actions to a variety of objects, it might be harder for them in the long run to be flexible with human language. Susanne Grassmann, a developmental psychologist and psycholinguist at the University of Groningen in the Netherlands explains, “Chaser was trained to do different things with different objects, and she differentiates between what is the object label and what is the action command, meaning what to do with that object.”

Ramos notes that Sofia’s relationship with certain objects was a bit different. “Throughout the training, we always paired ‘stick’ with ‘point.’ As a result, it was difficult for her to perform any other action toward the stick beside ‘point.’ If we had trained her ‘stick: sit,’ ‘stick: point’ and ‘stick: fetch,’ she would have learned that multiple actions can be directed toward the stick, and her response would probably be different. For example, when presented with a novel object, such as a toy bear, she could direct a number of different actions toward the bear, but there was a reluctance to change her action towards the stick, which could have to do with the rigidity of training.”

And even if you do explicitly teach that different words have different meanings, it can be challenging. Ramos found that learning the names of objects is not always easy for dogs. “It was hard for Sofia to learn to discriminate the names of her first two objects, but after the initial discrimination, it was like she learned to learn. It became easier,” recalls Ramos.

“Because this type of learning can be challenging, service dogs [who have little margin for error] are taught a limited, but instrumental, set of words,” explains Kate Schroer-Shepord, a qualified guide dog instructor at Guiding Eyes for the Blind in Yorktown Heights, N.Y.

Pilley found that dogs’ success at object learning depended upon the training method used. “When we put two objects on the floor and asked dogs to retrieve each object by name, they couldn’t do it; simultaneous discrimination wasn’t working. Instead, Chaser was able to learn the names of objects through successive discrimination. She would play with one object in each training session, and through play, the object assumed value. We’d name the object, hide it and ask her to find it. Discrimination testing between the names of different objects occurred later.”

Words or Melody?
Are these just “type-A” dogs whose accomplishments cannot easily be replicated? After all, most dogs aren’t explicitly taught words as described above, yet they interact with us talkers in ways that make us feel like we’re on the same page. “Dinnertime!” “Wanna go for a walk?” “Where’s Dad?” elicit an appropriate “bouncing dog” response. But are most dogs attending to our actual words, or are other factors at play?

Dogs derive an enormous amount of information from contextual cues, particularly our body movements as well as tone and “prosody” — the rhythm, stress and intonation of our speech. “When people talk to dogs, dogs pay attention to the melody and the mood to predict what is happening or what will happen next,” explains Fischer.

Fenzi says that dogs can just as easily respond to gibberish as to real English words; “I could go through every level of AKC obedience from the bottom to the top saying, ‘Kaboola,’ and the dog could succeed.” In many cases, dogs may be understanding tone rather than individual words.

“One of the most notable differences between novices and professional trainers is the ability to modulate the prosodic features of their speech,” notes McConnell. “The pros learn to keep problematic emotions out of their verbal cues, like nervousness in a competition, and to use prosody to their advantage when it’s advantageous, for example, to calm a dog down or to motivate him to speed up.”

In another study, Ramos explored whether, when taken out of context, dogs knew the words relating to toys they were thought to know. Most did not, much to the surprise of the owners. When the verbal skills of Fellow, a performing German Shepherd from the 1920s, were tested outside their customary contexts, Fellow knew only some of the words and actions that his owners thought he understood.

While many owners deem their dogs to be word-savvy, their reports tell a different story. The Pongrácz survey found that many words and phrases were executed only in contextually adequate situations (for example, saying “bedtime” when it’s dark and you’re in your pajamas rather than at noon when you’re in your work clothes). As with Fellow, this suggests dogs might not be attending to only words themselves.

Put Words to the Test
Does Rufus understand your words as you intend them, or does he have a different understanding? If you always use a word in the same context, it’s easy to assume that you and your dog define it identically. Changing the context in some way offers a better understanding of what the dog perceives.

McConnell initially thought Willie knew the name of her partner, Jim. “To teach Willie, I would say, ‘Where’s Jim?’ and Jim would call Willie over. When Willie consistently went to Jim, I’d say it as Jim was driving up, and Willie would run to the window. One day, Jim was sitting on the couch, and I said, ‘Where’s Jim?’ and Willie ran to the window, all excited. This difference in definitions is more common than people realize — dogs don’t have the exact same concept of words that we do.”

While there is no question dogs can understand verbs, their definitions might differ from ours. McConnell shares a classic example that she learned from Ian Dunbar, founder of the Association of Pet Dog Trainers. “What do dogs think ‘sit’ means? We think ‘sit’ means this posture we call ‘sitting,’ but if you ask a dog who is sitting to ‘sit,’ he will very often lie down. To him, ‘sit’ might mean get lower, go down toward the ground.”

Many people tend to overestimate their dogs’ facility with words and assume that dogs and humans have a shared understanding. Because a dog responds in one context and not in another doesn’t mean he is being disobedient. As Tom Brownlee, master trainer with the American Society of Canine Trainers and instructor in Carroll College’s anthrozoology program, candidly advises owners, “If a dog’s not getting ‘it’ — whatever ‘it’ may be — then you are doing something wrong. It’s our job to help them understand.”

When you talk to your dog, consider that the words you speak might not carry the same meaning for both of you. Instead, other aspects of communication might be more relevant. Maybe the real lesson is that context, prosody and tone — rather than dictionary definitions of words — are vitally important for human communication, too.
 

This piece is dedicated to Professor César Ades (1943–2012) and Dr. Penny Bernstein (1947– 2012). While their exceptional contributions to the fields of animal behavior and psychology endure, their presences are greatly missed.

 

News: Guest Posts
Toy Alert
Study finds Hormone-disrupting Chemicals Leach from Some Plastic Toys

The toy aisle is meant to be all about fun, but recalls, toxic imports and a dearth of regulations have left dog owners facing tough choices. Many toys are made of plastic and may contain chemicals that interfere with hormones.

A new study by researchers at the Institute of Environmental and Human Health at Texas Tech University shows that BPA and phthalates, chemicals that disrupt hormones, “readily leach” from plastic or vinyl bumper toys used to train retrievers.

Philip Smith, a toxicologist and co-author of the as-yet unpublished study, uses plastic bumpers to train his Labrador Retrievers, Bindi, age 11, and Huck, age 5. He wondered if the bumpers might expose them to hazardous chemicals.

In fact, the compounds are hard to avoid. BPA, the building block of polycarbonate plastic, is found in most food and drink cans; phthalates are common in food packaging, personal care items and vinyl plastics.

“BPA and phthalates come from many, many sources” besides pet toys, Smith says. So a dog’s “cumulative exposure may be significant.”

The study, conducted by graduate student, Kim Wooten, is one of the first to examine these chemicals in pet toys. In children’s toys, some phthalates have been banned in the U.S. and the European Union. In July 2012, the U.S. Food and Drug Administration banned BPA in baby bottles and children’s drinking cups.

Although their health effects in dogs are unknown, the hormones they interfere with regulate many biological functions.

Studies done mostly with rodents have linked BPA and phthalates to impaired development of reproductive organs, decreased fertility, diabetes and obesity, cancers, and behavioral and attention problems.

No, dogs are not mice. There are “species sensitivity differences” in regard to toxics, Smith says. For example, dogs are at greater risk than humans from eating chocolate. But while their sensitivity to synthetic chemicals may also differ, “we are unaware of specific reasons why they might respond in a significantly different manner.”

Available data suggests that the most vulnerable pets may be pregnant females “and perhaps young animals like puppies.”

According to a 2012 pet health report by Banfield Pet Hospital, some cancers and other diseases in dogs are increasing. “The rate of overweight and obese pets has reached epidemic levels in the U.S., affecting approximately one in five dogs and cats.”

The causes are unknown, but Smith says it’s possible that endocrine-disrupting chemicals, including phthalates and BPA, play a role.

Certain aspects of canine cancer suggest that dogs are sensitive to them, he says. For instance, exposure to estrogens raises the risk for mammary cancers. For metabolic disorders such as obesity and diabetes, researchers are finding that some hormone-disrupting chemicals appear to “affect metabolic endpoints, in addition to reproduction and behavior.”

For the toy study, the researchers tested orange and white bumpers from two unidentified makers, using artificial saliva to simulate a dog chewing a bumper. The amount of toxics released in a dog’s mouth couldn’t be determined due to the use of simulated saliva,

But what is a high exposure in dogs?

“We are not aware of any exposure guidelines pertaining to these particular chemicals and dogs,” Smith says.

They suspect the levels released from the bumpers would be very high, though, compared with children’s toys.

The study also examined BPA and phthalates from ordinary plastic pet toys sold in stores. The bumpers leached more, but the results suggest that the other toys might have released other hormonally-active chemicals.

Smith highlights the uncertainty that shoppers face, saying the bumpers might have been made from different materials, or perhaps the packaging limited the release of some chemicals before the experiment.

Or, the less affected toys may have involved “materials that are also used in the manufacture of children’s toys.”

“We’re not really sure, but intend to pursue the question further.”

Good thing for pet owners.

“Given the extent of plastics in the human-canine environment,” Smith says, avoiding the chemicals entirely may not be possible.

But not all plastics are the same. When it comes to leaching of chemicals “each type is very different.”

“That is why studies on individual products are important.” Pet owners need the information “to make thoughtful decisions.”

Some pet toy makers say they use BPA-free plastics.

But owners may wonder why it’s even a question. Why should they have to worry about chemicals in toys or migrating from cans, even into “organic” food, to add to their dog’s exposure?

At least—at last—it is being studied.

Smith’s team plans to continue studying the exposure of pets to chemicals. “We think there is a great deal to be learned about potential pet and human health impacts from chemicals in the environment,” he says.

And as they learn, Smith says they hope to yield the data needed “to inform decisions about how we manufacture pet products, which ones we buy, and what we allow our pets to chew.”

Good Dog: Studies & Research
Do DNA Tests Reveal Genetic Secrets?
The Beauty of Diversity

For those of us who love dogs, using DNA tests to deconstruct our mongrel pooch’s mysterious heritage is appealing because we want to be able to answer the question, “What kind of dog is that?” Companies say that DNA-based diagnostic tests, which sell for about $60, can answer the question by comparing your dog’s DNA to over 100 of the most popular breeds. But are the tests accurate? I decided to find out.

Chance, a 10-year-old mixed-breed dog who has lived with me for six years, was my guinea pig. I tested his DNA using three different tests. In 2008, when I wrote the prequel to this article (read it online at thebark.com/dna), I had his ancestry tested with the Canine Heritage Breed Test. At that time, the company used 96 markers and tracked them to 38 breeds. A marker is a gene or DNA sequence on a chromosome that indicates “breedness.” The labs claim that the markers they use are 99 percent accurate.

In May 2012, when I began doing research for this follow-up article, I tested his DNA with the amplified Canine Heritage Breed Test again because it had been substantially improved to 400 markers and 120 popular breeds. I could have paid $25 to upgrade the 2008 test. But to be fair in my test-of-the-tests experiment, I submitted his cheek swab under a different name and without a photograph, just in case, as many people believe, the tests are a scam. In addition, I used the MARS Wisdom Panel Mixed Breed Identification Test. Mars looks at 321 markers and includes 185 breeds in its database.*

To analyze and compare the results fairly, I needed to find out if the tests were processed the same way, and I researched the history of the breeds identified in Chance’s ancestry.

Comparing the Tests
Each lab analyzes DNA the same way. Upon arrival, samples are logged, tracked and monitored. DNA is extracted from the cheek swab and isolated, and copies are made to ensure a sufficient amount for processing. The genetic material is then chemically enhanced and run through equipment that looks for markers in the dog’s DNA that match breed markers in the database.

If a primary parent breed can’t be identified in the DNA, the program will look for a secondary grandparent breed, and so on and so forth, until it eventually clusters with a distant breed (if there is one). If there are no purebred ancestors, remnant breeds will be sought.

To identify markers that characterize a breed, labs take samples from multiple thousands of individual dogs representative of more than a hundred breeds. However, those dogs differ from one laboratory to the next. Although their sample sizes are big enough to absorb minor differences, no two dogs are exactly alike. Plus, line-bred dogs can affect results. For example, Labrador Retrievers bred exclusively for hunting may be more like each other than they are like the breed.

Finally, descriptive terminology differs. Canine Heritage uses primary, secondary and in the mix. Wisdom Panel uses parent, grandparent, great-grandparent and next best breed matches that include percentiles.

Chance’s Results
In total, I tested Chance’s DNA three times. I used the Canine Heritage test twice, in 2008 and 2012, to find out if the expanded breed library would affect the results. (It did.) I also used Mars Veterinary’s Wisdom Panel**. Although results differed, cumulatively the tests indicate that Chance is a mix derived primarily from spitz dogs and large terriers, with a tablespoon of sight hound, teaspoon of herding dog, pinch of guard dog and smidgen of bird dog.

Because Chance has no purebred parent, his strongest signal would come from a purebred grandparent. One test indicated a Siberian Husky grandparent. However, the other two tests claimed he has no purebred parent, grandparent or great grandparent. In any case, all three tests concur that a combination of spitz breeds provides the strongest signals in Chance’s ancestry — Siberian Husky, Alaskan Malamute and, to a lesser degree, the Pembroke Welsh Corgi, a breed with some spitz lineage. Although it transmits a faint signal, the Pembroke Welsh Corgi is the only breed that showed up in more than one test. The white German Shepherd and blackand-tan German Shepherd, strong and weak signals respectively, are both named as ancestors and are admixtures of one another. Although they are herding dogs, it’s probable that both breeds have some spitz lineage. The Japanese Chin, a miniature Asian breed derived thousands of years ago from larger mastiff and spitz dogs, is also a fairly strong signal.

Large terriers make up the next strongest signals in his DNA. The German Pinscher, Standard Schnauzer and Doberman Pinscher are closely related. German Pinschers were used to develop the relatively new Doberman Pinscher breed. The Standard Schnauzer, originally called the Wire-haired Pinscher, is directly related to the German Pinscher. Sight hounds are mentioned in two tests. In the late 1800s, Borzois were likely mixed with Huskies to increase speed, and terriers were mixed with Italian Greyhounds.

The weakest signals, in some cases less than 2 percent of his makeup, include a ragtag group of breeds, including Border Collie, English Setter, Cocker Spaniel and Leonberger.

Making Sense of the Findings
Cumulatively, the three tests indicate that Chance is related to 16 different breeds within all AKC breed groups except scent hounds. So the question shouldn’t be, “What kind of dog is that?” A more appropriate query is, “What kind of dog isn’t that?”

The ancestral breeds named in the three tests seem absurdly disparate, but they are not contradictory. They all point to one truth: only a few degrees of separation differentiate Chance from all modern breeds. This is because most purebred dogs have a crippling lack of genetic diversity, which is the unintended consequence of modern breeding practices.

Except for 14 ancient breeds — Afghan, Akita, American Eskimo, Basenji, Canaan Dog, Chinese Shar-Pei, Chow Chow, Dingo, Finnish Spitz, New Guinea Singing Dog, Saluki, Samoyed, Shiba Inu, and Siberian Husky — all our modern breeds were developed in the last few hundred years.1 Although each has its own DNA fingerprint, they have so little genetic diversity that if you go back far enough, the DNA of almost every dog, mixed breed or purebred, will cluster with a few common ancestors. This finding raises the question, “How can breeds that look so different be so closely related.”

The complex DNA of stray mutts on the mean streets of, for instance, Lugazi, Uganda, or Zorzor, Liberia, may answer the question. Ubiquitous freeranging dogs living on the fringes of human settlement are not, as previously believed, semi-feral, mongrelized purebred dogs, but rather, are genetically distinct and subject to the pressures of natural selection. Some populations have been isolated for hundreds, if not thousands, of years. Subsequently the village dog genome remains complex and unabridged.

Suspecting that village dogs may be pure genetic remnants of ancient dogs, Adam Boyko, assistant professor in the Biomedical Sciences Department at the Cornell University College of Veterinary Medicine, co-founded the Village Dog Genetic Diversity Project with his colleague Carlos Bustamante, a genetics professor at Stanford School of Medicine.

The project is a worldwide collaboration of researchers, volunteers and veterinarians who gather canine DNA samples along with photos and information on weight, age, body measurements and coat color. The samples are analyzed at the Canine DNA Bank at the Baker Institute for Animal Health, part of Cornell’s College of Veterinary Medicine, which maintains a growing DNA archive of dogs worldwide.

The scientists believe their work will shed new light on when, where and under what conditions dogs were domesticated, and how dogs have adapted to human settlement, environmental stress and disease.

The first phase of the study included collecting samples from modern breeds, their mixed-breed relatives, breeds reputed to be from remote regions of the world and African village dogs. In 2009, they reported that African village dogs are a mosaic of indigenous dogs descended from more ancient dogs that migrated to Africa.2 Findings also indicated that their genome is being eroded at an alarmingly fast rate as they mate with recently introduced modern dogs. Researchers are now scrambling to find dogs in even more remote locations. In the summer of 2012, workers began collecting DNA samples in Liberia and the Democratic Republic of the Congo.

On a continuum, gray wolves, the progenitor of all dogs, have the most genetic diversity, and purebred dogs have the least. Village dogs’ diversity lies somewhere in between. Because purebred dogs are the result of strong selection for exaggerated traits, they have only a fraction of the genetic diversity displayed by village dogs. The genetic variant that underlies a desirable trait, whether it’s extreme size or intense behavior, has become fixed, wiping away not only competing variants but also variants associated with nearby genes.

Genes located close to each other on a chromosome are said to be linked, and tend to be inherited together or, conversely, wiped away at the same time. Thus, a trait that isn’t selected for can be wiped away simply as a result of being in the wrong place at the wrong time. If that trait happens to affect, for instance, immune response to disease, then that could be a problem.

By comparing the genome of village dogs to that of purebred dogs, scientists hope to be able to identify what’s been lost as a result of intense artificial selection. Dr. Boyko notes that “village dogs offer a chance to understand the mechanisms of certain genetic diseases. Knowing what those genetic variants are might be the first step towards invigorating genetic diversity in some modern breeds.”

The Significance of Canine Origin
The closer a village dog population is to the original canine domestication event, the closer it will be to the gray wolf and the more genetic diversity it will have. Will Dr. Boyko’s village dogs turn out to be close relatives of the first dogs? Not likely.

Previous studies suggest that dogs originated in places as varied as Eastern Europe, China’s Yangtze River Valley and the Middle East. In a 2002 study, researchers pinpointed East Asia as the place of origin. However, some scientists think these dogs are descendents of an even older population that developed in a different place. Dr. Boyko’s findings confirm this. African village dogs have about the same amount of genetic diversity as those in the East Asian study, suggesting that both groups are the same age. It’s possible that both populations originated together somewhere else and then migrated to East Asia and Africa at about the same time.

To thoroughly complicate matters, the Canidae family does not play by the same rules as most other mammalian families. Unlike, say, horses and donkeys, dogs, wolves, coyotes and golden jackals can interbreed and produce fertile offspring. Consequently, following the genetic trail from domestic dog to wolf leads to a lot of stops and starts and many dead ends as well as plenty of headaches for evolutionary biologists.

A Multi-Disciplinary Approach
Where to now? Some researchers think it’s time to go back to the road not taken. In a paper published in June 2012, Greger Larson, an evolutionary biologist in Durham University’s Department of Archaeology and the paper’s lead author, said that by putting genetic discoveries in the context of archaeology, history and biogeography, the study of the geographical distribution of species might help make better sense of what we already know.3

As Dr. Larson notes, “There has been so much admixture since dog domestication began, and especially in the last few hundred years, that looking at modern dogs is always going to be problematic. There may be modern populations that are less ‘corrupted’ or admixed, but even they will possess a legacy of several thousand years of crosses with large numbers of populations, and even wolves.” He adds, “The only way forward is to focus on other methods, including, but not limited to, ancient DNA from archaeological dog and wolf remains. And of course, there is the wider interpretation and understanding from lots of other fi elds to put it all in context.”

In the paper, researchers discussed an interesting pattern that emerges when sites with archaeological dog and wolf remains are overlaid onto maps showing the historical distribution of wolves. First, the archaeological remains are not found in the places where ancient breeds are believed to have been developed, intimating that dogs may have been domesticated multiple times from local wolf populations. Second, most of the ancient breeds come from areas where wolves never ranged, suggesting that humans had dogs as they migrated around the globe. Furthermore, dogs only appeared in these locations after agriculture was introduced.

The canine genome’s full story continues to evade scientists, but as DNA technology advances and analysis becomes cheaper and faster, researchers are optimistic that the answers they seek are right around the corner.

Will I continue to test my future shelter rescue mutts to find out who they are, even though I know that the answers will be the same — all modern dogs are so closely related that it’s almost impossible to discriminate ancestry? Probably. Other mysteries lie hidden in our dogs’ DNA. The idea that an animal can be morphed into so many extreme shapes and behaviors yet remain a simple combination of only a few stem parents is one of them.

We like to believe that scientific discovery advances tidily, fact by fact, to prove an irrefutable truth. But science is a messy business. And there is hardly a better example of just how messy than the search to tease out the mysteries hidden in the canine genome.

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