Dr. Clive Wynne: My understanding from archaeologists, geneticists, we don't believe that people created dogs in the first instance. What probably happened was that sometime during the last Ice Age, maybe 15,000 years ago, our hunter-gatherer ancestors, in certain places, discovered locations that were so rich that they could settle down. But, once they became settled, they started doing what is characteristic of human beings, they started creating piles of trash, and those piles of trash attracted many different animal species.

But, anyway, in some parts of the world, wolves joined the fellowship of animals that started scavenging on our ancestors' trash, and as they did that, they placed themselves in a new niche, and they placed themselves under a new set of selection pressures, and those selection pressures are what, in the first instance, created dog-like animals, created animals that were no longer clearly wolves.

Jesse: How many wolves are there out there and how many of them are available to researchers?

Dr. Monique Udell: That's an excellent question, and part of the answer to that question is, "What do we mean by wolves?" So, there's actually more than one species of wolf. If we look, not only North America, there are multiple species, but then, there's also species of wolves around the world. I don't know the exact number off the top of my head, but if you look at the range of those animals that we can actually work with at least for studies like this in terms of social cognition where we need to be able to potentially go in with the wolves and interact with them, we're talking about a relatively small number.

Dr. Clive Wynne: My suspicion is that our ancestors initially were not very happy having wolves hanging around the edge of their encampments, but there was nothing they could do about it, and in time, they came to realize that their resident wolves were not as big, and scary, and dangerous as the outside wolves, and bears, and other animals, and these resident wolves would make a fuss when unfamiliar wolves, or for that matter, unfamiliar people came close to your encampment, and that was the beginning of a useful relationship.

Jesse: It's interesting to think, also, that because there were dogs present in both the Americas and the old world, is the conventional wisdom that dogs crossed over with humans on the Siberian land bridge when humans first came to the Americas or that dogs were sort of independently domesticated or self-domesticated or whatever from local wolf populations in both Eurasia and the Americas?

Dr. Clive Wynne: This is going a bit beyond my range of expertise, but I'm pretty certain that the dogs in the Americas came with humans over the Bering land bridge, that it was not an independent domestication event, I'm pretty certain. But, that remains up in the air with different groups. The geneticists never seem to be able to agree with each other, and you get different postulated places of origin of dogs and you get argument over whether dogs arose only once or arose on multiple occasions on different parts of the world.

Dr. Monique Udell: And I think it's really important to recognize that most of the research that has been done on dog cognition has been done with a very small subset of the domestic dog population as well. So, typically, those sorts of research studies are done with pet dogs, and pet dogs only make up a small proportion of the world's population of dogs. In fact, the great majority of the world's dogs, something like three-quarters of the world's population are actually free-roaming scavengers.

Jesse: Wow.

Dr. Monique Udell: It's actually pretty similar, then, when you compare the types of wolves that we're looking at. These hand-reared wolves that have this bond with humans, they're not the same as, necessarily, the worldwide population of wolf that is living a wild-type existence. But, when you're making comparisons between the dogs that we live with and you're trying to understand what components of their behavior might be influenced by genetics versus life experience, then you really then have to try to compare those dogs, our pet dogs, with wolves that have had similar positive social experiences with humans.

Jesse: That is a really fascinating statistic that you just said that three-quarters of the world's dogs are essentially wild dogs. That implies that, depending on how you look at it, dogs are better-adapted to life on planet Earth than things like wolves, which is interesting since dogs, I guess, started out in this symbiotic relationship with humans and have an active life beyond that, or at least not living directly as human pets.

Dr. Monique Udell: Yeah, absolutely, and that's actually not only true of domestic dogs. They're all genetically domesticated, but they are living that free-roaming sort of wild existence in much of the world. You can find the same thing in other urbanized animals. So, if you think about pigeons or you think about rats, or you think about squirrels, urbanized animals, animals that do well in human environments, even if they're not living as pets, often do really thrive in terms of population numbers compared to some of their wild counterparts.

Jesse: Strictly, biologically, are all dogs still the same species? Can you still interbreed any two dogs from any poles of the dog phylogenetic universe: a mastiff with a Chihuahua and still get a fertile offspring?

Dr. Clive Wynne: Not only are all dogs part of the same species, they are actually all part of the same subspecies. Today, dogs are no longer spoken of as canis familiaris, which is what people are taught in school. For at least a decade, two decades, dogs have been classified as a subspecies of wolf. So, dogs are canis lupus familiaris, and in fact, dogs and wolves can and do interbreed and create viable offspring, and so do all the species in the genus canis. So, coyotes, jackals, wolves, dogs, dingos, New Guinea singing dogs, they are all capable of and do interbreed and produce viable offspring.

One thing I find very surprising and interesting is that all modern breeds are a creation of just the last couple of centuries. The notion of a breed, as we understand it today, as a closed breeding population, where you must not breed your German Shepherd to a dog that is not also registered as a German Shepherd, that is a much more recent phenomenon than most people seem to realize. Actually, the first dog show in the modern sense took place in 1859, which is the same year as the publication of Darwin's Origin of Species, by coincidence.

Dr. Monique Udell: Domestic dogs, by in large, are capitalizing on a specific niche, which is around or within human settlements, and this is true back from they were first domesticated in the range of 14,000 years ago all the way up until present day. You typically find them in fairly close proximity to humans and utilizing human resources for survival even if humans aren't necessarily directly caring for them or taking them in as pets.

Jesse: As far as your studies of dog cognition and wolf cognition and pitting the two against one another, seeing where those differences lie, tell us a little bit about that, what were you expecting to find, what have you seen?

Dr. Monique Udell: I've done a range of studies with dogs and wolves and comparisons. When we initially started with this research, we were interested in looking at aspects of social cognition that were thought to be really important to the dog-wolf distinction. It had been suggested that, for example, dogs would be really responsive to human gestures, to body language, to our vocal commands. So, a lot of our early research was focused on trying to understand how successful human-reared wolves would be on these various tasks, and what we found is that, in many cases, wolves are very good at social cognition tasks, which makes sense because they engage in really complex social interactions with each other as well.

The recent studies have been a little bit different. We kind of have taken a step back and said, "Where do we see these characteristic differences in wolves and dogs crop up most commonly?" and one of those areas is that dogs, through domestication, are more juvenile in their behavior than wolves, and this can be represented in a number of ways, and one very noteworthy way is the amount of time they spend in close proximity to people or other companions and the amount of time they spend looking at, or we can even view it as gazing or staring at their companions. If you think about a human child and how they're just always inquisitively looking up to adults and learning, and we see the same kind of thing in dogs.

A lot of our more recent studies have been asking the question, "Maybe it's not that dogs are necessarily smarter than wolves, maybe it's not that they think more like humans, but maybe they just spend much more time watching us, wanting to be in our proximity, learning from us, and responding to our behavior," and that's what a lot of our more recent studies have been trying to address.

Jesse: I could see where that would make sense. It's kind of like if you're in medieval courts, everybody's watching the king and the queen to see what they think is cool and then trying to mimic that or use that to their advantage, and it's kind of like that, I guess, if you're a dog living in a human household.

Dr. Monique Udell: Absolutely, and it's like, in some ways, dogs never grow up, and I think that that is really adaptive for dogs in a number of reasons. One, people really like the childlike aspect of dogs. We want our dogs to be playful and excited when we come home, we want them to watch us, we want them to listen to us. So, those juvenile-type characteristics that we see in lots of species, the fact that dogs maintain some of those into adulthood could be really beneficial to them.

On the other side of the coin is that because they spend so much time watching us and seeking our proximity, they have a lot of opportunity to learn those things, to learn what types of things that we expect of them, to learn when it is we're going to do something, like when we're about to leave for work, or when we're about to go on a walk, or when it may or may not be acceptable to engage with a particular item. So, dogs are really sensitive to these things, and this also helps facilitate their success in human environments.

Jesse: In the last couple hundred years where there has started to be much more fenced in, closed, controlled breeding for the various breeds, and you've seen this differentiation of all the breeds that we have today, I guess maybe talk about some of the effects that we see cognitively on the different dog breeds in addition to the various shapes and sizes.

Dr. Clive Wynne: Sure. It was in the late 19th century that people really started setting up stat books, closing them. German Shepherd, for example, was developed in the last years of the 19th century, and the guy who did this is a German called Max von Stephanitz. He wrote a book about what he'd done. He'd traveled around Germany looking for the perfect example of a German Shepherd dog. Now, when he found that dog, he bred only from that dog, from that male.

Before the modern understanding of biology, breeders thought that the inheritable material only came from the male. They thought of the female simply as the vessel that carried the new generation. In devising the German Shepherd, all registered German Shepherds alive today are descended from this one male dog. So, you have phenomenally intense inbreeding, which captures and guarantees the morphology of the animal. It also captures certain diseased genes. So, I think the number is two-thirds of all Golden Retrievers die of cancer, and it's a very small number of cancers, and that's because, along the way, some cancer genes got captured as well as the desired genes for morphology.

At some level, there are behavioral differences between purebred dogs. Only Border Collies and a few other breeds have this intense drive to herd. But, what I find more interesting, really, than these obvious and trivial behavioral differences between certain breeds is the fact that if you give dogs a wide-ranging temperament test, while some people would call it "personality test", and you assess as many different dimensions of their behavior as you can think of - their inclination to chase a ball, their willingness to play games with people in other ways, their general aggressive propensities, and so on - if you do a wide-ranging temperament test, then actually -- well, there are two major studies, both used over 13,000 dogs. One of the studies found that the amount of variation within a breed was 80% of the variation between the breeds, and the other study actually found more variation within the breeds than between the breeds.

My take-home is that, actually, breed is not as predictive of temperament as people generally naturally assume, especially if you're not looking for a dog to carry out its traditional working role. So, you're not looking for a dog to do herding or whatever task these dogs are originally bred for. If you're not looking for those originally-bred behaviors, then actually, the differences between breeds are not great at all. Furthermore, which concerns me much more, when you're looking at a mix-breed dog, that we know that over 95% of the dogs in shelters are mix-breed dogs, there's no reason to think that even if you could identify which breeds went into those mongrels, there's no reason to think that they would tell you anything useful at all about that dog's behavior.

Jesse: I guess that lines up pretty nicely with what we know about human brain's inheritability that so many of our mental attributes seem to be highly heritable, but also that overall heritability is spread over so many different individual genes that you can very rarely point to one particular gene and give it credit or blame for how a person turned out, or dog in this case.

Dr. Clive Wynne: Right, so it's very interesting to compare to the situation with our own species, because back when true-bred dogs were being developed, the idea of having true-bred humans was also acceptable by educated people, and back in those days, good old bad old days of the British Empire, there were racist expectations that certain races of people were good for carrying things, other races of people were good for figuring out puzzles, the way the British took Indians to Africa because they thought they needed them to do the more intellectual work that they didn't feel the Africans were good for. All of those kinds of thinking, which are a total anathema today, and we know are just so wrong and pernicious, those kinds of thinking were what was a deep part of, deeply integrated into the creation of closed breeds of dogs. It's interesting where, in humans, I think, I hope all the educated people I know have thrown off that thinking about our own species, we still think that way about dogs.

Now, to be fair, purebred dogs are much more intensely inbred than any race of human beings ever was. The variation in behavior with inbreeds is close to, if not greater than, the variation in behavior between breeds, so long as we're excluding from the discussion behaviors specifically bred into certain breeds of dog like herding, and guarding, and so on, things like that.

Jesse: What do you think are some of the biggest misconceptions that people have about the way that dogs think?

Dr. Clive Wynne: I do not think that dogs have any special kinds of psychological cognitive adaptations to living with human beings. I live with a dog, and it certainly is true that dogs are remarkably sensitive to what people are doing, and the textbook, what's become the standard case example of this is that if you put two containers on the ground and you put to one of them, then your dog will go and investigate the container that you pointed at. You can try this with your own dog. It works in three-quarters of all cases that the dogs will do this, and it's been argued that that kind of behavior shows that dogs have a unique understanding of human intentions that no other animal species has. It's been argued that wolves cannot do this, it's been argued that chimpanzees cannot do this. Chimpanzees, of course, are our closest surviving relatives, and they have much larger brains than dogs or wolves.

But, I do not believe that's true. I think that's a serious misconception. What happened was that people were comparing dogs who lived as human companions in homes who depend on human beings and human actions for the fulfillment of all of their needs. They were comparing those dogs to wolves that were living in captivity, but didn't have the same kind of relationship with human beings.

Dr. Monique Udell: The studies that we do with wolves that are hand-raised often range in the number of 10 to 15 animals because those animals have been raised a very specific way. They've been socialized from the time they're two weeks of age and raised with people, and we can go in and interact with them much in the same way we can interact with the dogs that we test. There are little pockets of these human-socialized wolves around the world, but less than maybe 100 total that have this degree of socialization. So, it does limit our ability in this way.

Jesse: So, with a small handful of research-friendly wolves, how are they being put to use?

Dr. Monique Udell: One study that we have been working on recently has been what we call the solvable task. This originated with a version of the study that has been done by other researchers around the world called an unsolvable task and it was basically a puzzle box, and then the unsolvable version, what people typically do is they put some sort of food item in a container, and they typically give the dog or the wolf an opportunity to eat out of that container several times or maybe just knock a lid off to get the food, and then eventually they glue that lid down. So, this task now becomes unsolvable.

Jesse: Just so people can picture this, can you kind of explain what the dogs actually need to do to solve this puzzle?

Dr. Monique Udell: Basically, it's a Tupperware container. It has a lid on top, it has a rope through the lid, and there's a piece of food inside, and all the dog has to do, or the wolf has to do is get that container open in some way, so typically by removing the lid. Although, we've had a few creative canines actually crunch through the container on the side, or shake the container by the rope until the base came off and they had left with the lid in the mouth, and they could get at the food. So, they can solve this puzzle in any way they see fit. They just have to get this food out of the container. It's actually a pretty simple task.

What's interesting is wolves almost always solve this task and they do it quickly. Their whole trial time is about two minutes long. Wolves have no trouble with this. Occasionally, dogs will solve it as well, but the great majority of dogs do not solve this task, and what's interesting is not so much that they don't solve, but that they barely try. Typically, they're very interested in the food, they'll run up, they'll sniff the container. In fact, they'll do this even faster than the wolves will. You place that container down on the ground, or the owner places the container down on the ground, takes three steps back, and within a couple of seconds, the dogs are either looking at their owner, they're laying next to their owner, or they're sitting quietly. Occasionally, they'll explore the room, but by in large, they won't even attempt to solve this task at all.

This is really interesting to us, because what it means is that, in these prior studies, it wasn't that these dogs were looking back to the person to help in a time of need. They're simply yielding either to the person being there, exhibiting complete deference to the person, expecting that person to provide to them, or they're just lacking in this individual solving problem persistence, potentially because they are now capitalizing on a niche where they're relying on scavenging or provisioning from people to a far greater extent than we would expect from animals like wolves who have to actually go and solve these problems themselves.

Jesse: Did you try it with dogs of varying degrees of hunger? I'm wondering how much food desperation versus, "Ah, I know my owner's going to give me food in the next couple of hours anyway," might play into it.

Dr. Monique Udell: Yeah, and it's an interesting question. In these particular studies, we did not explicitly deprive them of food. We did typically test at times that were not directly following meal times, and both the dogs and wolves were being fed on a normal schedule, at least the owned dogs and wolves. However, we have also done this now with populations of free-living dogs. So, dogs that are in India, they're living that sort of more wild type free-roaming existence, and these are dogs that scavenge for a living. So, they're actively looking for food, actively looking for handouts, and what we found is that free-living dogs in India actually were less persistent on the task even than pet dogs. They actually spent longer durations of time looking at the human.

There's something fascinating going on here, and while lifetime experience likely plays a role, we believe that this might be one of those traits that represents a true divergence between dogs and wolves, this proclivity for approaching people, and watching people, and responding to the actions and behavior of potential social companions over independent problem solving. That is something that we see reliably in dogs that we just don't see in wolves once they reach adulthood.

Dr. Clive Wynne: If an animal is going to be sensitive to what people are doing, that animal needs to have had two crucial life experiences. The first thing is that early in its life, during a period that's called the "critical period for social imprinting", that animal has to have spent that period of its life with human beings. Only if the animal spends that early period of his life with humans will it come to accept humans as social companions, will it be willing to form social relationships with human beings.

Now, in our dogs, it's so easy to tame a dog, it's so easy to convince a dog that it should accept human beings and social companions. It's so simple that most people never even notice that they do it. If you have a puppy in your home, the puppy will, in the natural course of events, come to accept you as a social companion. You don't notice yourself doing anything to enable that to happen.

Back in the '50s and '60s, when ethical standards were different, experiments were actually done, and they reared dogs under conditions that they didn't see any human beings until they were three months old, by which time this critical period for social imprinting has passed, and those dogs, the researchers recorded, behaved in adulthood just like wild animals, and they were absolutely terrified of people, and there was nothing you could do with them, and so they just euthanized those animals.

Now today, I hope nobody would be willing to do that. We're not going to carry out an experiment and just euthanize the pups because we've created dogs that nobody can live with. That's absolutely unacceptable. But, there it is. Back in the '50s and '60s, standards were different, they did this. It proves the one thing a dog needs to have, any animal needs to have, if it's going to respond to human or social companions is it needs to have had enough exposure during the critical period of social imprinting.

Now, in dogs, what makes dogs a domesticated animal is that the critical period for social imprinting is very long, so it's very, very easy to do this. It probably lasts about three months. Without replicating this unethical experiment from the '50s and '60s, we won’t know exactly how long it is, but it's probably about three months long.

If you look at a wild animal like the wolf, the critical period for social imprinting is much, much shorter. It's probably something more like two to three weeks. That's why it's really difficult to tame a wolf, it's really difficult to tame a lion, it's really difficult to tame animals of any wild species because the critical period for social imprinting is very short. It has to be short. It's not a mistake. It's not a biological mistake. Because, outside of Disney movies, it's a really bad idea for an animal to grow up making friendships with members of other species, because you're always either predator, or prey, or both.

The only kind of animal that you can afford to have relationships with is your own species. Otherwise, you're going to get eaten, or you're not going to want to eat the animals you need to be eating, or a bit of both.

Jesse: On the puzzle box task, has there been a test case where dogs were tested with no human around, no researchers, or human chaperones, or masters so you could kind of see how they did it when just left to their own devices?

Dr. Monique Udell: Yes, absolutely. So, we also have a version of the test where we give the dog the same puzzle when they're left alone, and what's interesting is we see relatively low levels of persistence in that condition as well. In fact, they persist at about the same level whether a human is directly present or whether they're alone. Oftentimes, though, when we're looking at pet dogs, what they spend that time doing then is searching for their owner. Even when the person's not physically there, they still seem to be actively attending to those social cues, whether it be the scent that's left in the room, or the door that they walked out of. They still attend to that task.

Jesse: That reminds me of a little kid that skins their knee and they go look for mom before they start crying. It's like until mom can see them cry, they won't even bother crying.

Dr. Monique Udell: Absolutely. I think you hit the nail on the head again. Their behavior that we're seeing exhibited in these dogs is very much like, if anything, what we would expect out of a juvenile, and I think they're really capitalizing on that niche and that response of sort of juvenile-type behavior as successful in these environments. It makes them, maybe, more prosocial in some ways, it makes them more attentive to the stimuli, and they're really sensitive to the fact that people do provide for them, especially these pets, and that if they're around their people, they're looking at their people, they're seeking their people out, good things tend to happen. I think that what we see in wolves, it's not that they don't have this capability, but that they outgrow it, and dogs never do. They stay like children forever.

Jesse: That's interesting. Have you run the study on juvenile wolves to kind of test that theory out?

Dr. Monique Udell: We've run a number of other studies that are similar in nature with juvenile wolves, and we do find that, in many cases, they're showing prosocial orientations. They show the attachment behavior, they seek the proximity of people to a much greater extent than they do when they're adults. We haven't run the specific test with a sufficient number of juveniles to make that transition, but we've started collecting data on juvenile dogs, so dog puppies and adult dogs, and we're currently looking, also, to see if there's a developmental factor for dogs, but it would be fascinating to do it in wolves as well.

Jesse: Can you talk something about the perceptual differences between humans and dogs, how we see, and smell, and hear the world, and the effects that these differences on our overall cognition?

Dr. Clive Wynne: Mind you, I don't know if you've seen it. I haven't read it yet, but Nature, this week or last week, has an article claiming that human sense of smell is not as bad as we always make it out to be. I mean, assuming that when I finally read that article, it doesn't radically change my opinion on this topic, dogs certainly do seem to have a more sensitive sense of smell than humans do. That said, it seems like it's humans that are the odd one out, not dogs. That is to say we humans seem to pay exceptionally little attention to smell, so we humans, being primates, we're very, very visual, we're trichromats, we have three color channels, we discriminate colors more finely than most other vertebrates.

Dogs, like most vertebrates are dichromats. That is to say that their visual experience of color is similar to that of red-green colorblind people. They can discriminate yellows and blues from each other, and they can discriminate yellow and blue from red or green. But, when we see red and green as quite distinct sensations, to them, that's all part of the same thing.

Then, their visual acuity is not as good as ours either. Although, I can't think of a number for that off the top of my head, but certainly, their visual acuity is less. I mean, we're talking generalities here. We've done a series of experiments on dog sense of smell, and one of the first things that really surprised me was that, although some dogs have a wonderful sense of smell, other dogs do not. We were, at first, puzzled by this and we thought that we were getting something wrong, because everything we read just talked generically about dogs having a wonderful sense of smell.

But, it turns out that, for all that there are, some dogs have a very fine sense of smell, other dogs do not. We don't have the technology with our behavioral methods to be able to distinguish between the actual perceptual sense of smell in the narrow sense or the motivation to use your sense of smell. It could be that the dogs we tested who were unsuccessful in our tasks, it could be that they did have a sense of smell; they just were not motivated to show us what they knew.

But, this was surprising because we hadn't had this kind of phenomenon in other studies of other kinds. So, I do actually wonder whether it's the case of all dogs are using their sense of smell all the time. Generally speaking, dogs do have a finer sense of smell than human beings, but not radically better than other mammals. They have less vision, they seem to have better hearing. Again, there's considerable variability from dog to dog, and probably from breed to breed in all of this.

Jesse: What were the total numbers of dogs and wolves involved in this study?

Dr. Monique Udell: We've done it with quite a large number over the course of many studies. The original study, we were just comparing 10 pet dogs living in human homes, 10 in the shelter, and 10 human-socialized wolves, because at the time, the limiting factor was the number of human-socialized wolves that we could directly work with for this sort of research.

Since then, we've done several other studies that have had larger populations, so up to 60 dogs in a study, and we've run multiple studies now, so we're in the hundreds of dogs. It is fascinating because, while you do see individual variation between dogs, and you do see individual variation between wolves, the magnitude of difference between dogs and wolves is always robust and is always very large.

In all likelihood, we're still seeing some combination of lifetime experience, genetic influences, developmental factors. All of those things are always going to interact. When we're talking about any behavior, all of those things are important. But, when you see a huge reliable difference between dogs and wolves in almost every case, even when you're seeing that smaller individual variation within those subspecies, definitely, it suggests that there's something interesting there. Not only have we found this, but now we're starting to talk to other research groups around the world who are working with different populations of human-socialized wolves on very similar tasks and they're finding the same thing.

Jesse: You know what would be interesting is if there's that magnitude of difference between dogs and wolves reliably, it makes you wonder if there's similar, maybe smaller differences that would be persistent across different dog breeds.

Dr. Clive Wynne: Yeah, and there might be. People have looked at this with the older version of the task, the unsolvable task, and there was some indicator that, to some extent, breeds could make a difference, especially when we are talking about specific working population of dogs. Often, when you're looking at differences in social cognition or behavior between dog breeds, if you just take a large survey of a bunch of breeds without any sort of rationale for why you're choosing those breeds, you often don't find the differences that you might intuitively expect. Where you typically find the large differences in behavior or cognition between breeds is when you look at those breeds that have been selected, for example, for specific working roles.

We've done studies where we've compared livestock-guarding dogs, which is Anatolian Shepherds, and herding dogs, like Border Collies or Australian Shepherds, then compared them with Terriers, and these are going to be dogs that have actually been bred for specific motor patterns or specific types of behavior that the other breeds have been bred to not exhibit. And when you compare those sorts of things, even on the social cognition tasks, even if that wasn't the point of the initial breeding, you do tend to find some differences there.

That's something that we're moving forward and we're looking more at those questions of breed for those particular tasks, but those have definitely been true on other social cognition tasks.

Jesse: It seems like, as we've separated dogs into different purebred lines, mostly, we've been aiming for some version of some person's conception of cuteness. How much have we been mucking things up, biologically, as we try to turn dogs even cuter?

Dr. Clive Wynne: Well, it's interesting. Going back at least as far back as the Middle Ages 500 years ago, 600 years ago, people recognize that there were such things as sight hounds, which were dogs that you took hunting with you, and they relied on their sense of sight to find prey, and then there were scent hounds, which were hunting dogs which relied on their sense of smell to find prey. So, the notion that there are different breeds of dogs with different capacity in the visual or the olfactory domain is a very ancient notion, and the idea that you just articulated that certain breeds of dogs, because they've been selected simply to be pets, that those breeds of dogs might not have such good senses of smell, that's talked about in the non-technical literature and it comes up in the scientific literature.

But, we did a study which really surprised me. There was a paper came out a few years ago looking at the brain of the pug. The pug is a dog with a very smushed-in face. It has no real snout at all, and its brain is actually rotated inside the brain case, and the olfactory bulbs, which are the crucial part of the brain for at least initial processing of olfactory sensation, its olfactory bulbs are much smaller than any other dog. The authors of this anatomical paper wrote that their anatomical findings explained why pugs have such a poor sense of smell.

At this stage, I was working with my then graduate student Nathan Hall, and he said, "But, you know, I'm not aware of any paper that has actually looked at the olfactory capacity of the pug." We had a very simple olfactory task which could easily be deployed with different dogs. So, we did a study with a group of pugs, because they're the ones that allegedly have such a poor sense of smell, a group of German Shepherds, who are generally spoken of as having a good sense of smell, and are the dog of choice for most branches of the United States military and policy. So, they're very widely used for sniffer dogs. Now, we also included greyhounds because greyhounds are historically considered a sight hound, a dog that hunts by vision and not by smell. So, it seemed like an interesting comparison group to have.

To our total astonishment, the pugs actually performed far better than the other two breeds of dogs. The German Shepherds were surprisingly poor, and the greyhounds, we couldn't even get any data from because they didn't seem to perceive the smell stimuli at all.

At the moment, the dog world is a very interesting world. Now, I'm not actually suggesting that the military should start using pugs as sniffer dogs. There are a whole range of reasons why pugs would be impractical animals to use for that purpose. But, in this day and age, isn't it conceivable that we could do genetic studies and identify genes that are responsible for higher levels of success in olfactory tasks and breed dogs that are better at this? It's really surprising to me when so much depends on it. People put their lives in the hands, in the paws of dogs at airports and in military contexts, and yet we're not actually using animals that have been designed by science to be the best that they can be for this.

Jesse: I imagine that there are people who, when they hear about dogs being tested against wolves, some people are kind of going to be rooting for the dogs, they're the home team, and other people are going to be rooting for the wolves because they're more natural and they're kind of autonomous, I guess, in a way that dogs aren't. And it seems like the studies that you've done, you could kind of interpret dogs not doing as well on this test in one of two ways. You could interpret it as dogs are just lazier and waiting for the handout from humans, and so they give up quicker, or you could interpret it as dogs are like a good soldier and want to check with their superior officer before they sort of go off half-cocked. Is that just sort of a matter of conjecture at this point or have you done further studies to try to see which of those two interpretations we should lean towards?

Dr. Monique Udell: I think any way you interpret it, it's brilliant, because dogs are so successful, and it's working for them. I think it's maybe a combination of both that dogs are in a situation where they don't necessarily need to have some of these predispositions for persistence on solvable tasks or independent tasks. Maybe they can be a little bit more vigilant or laid back and conserve energy.

We really think about the natural world, what is successful? Success is being able to be successful while exerting as little energy as possible if you're looking at efficiency in animals. It's sort of brilliant, right? If dogs have a niche or a strategy where they can move into people's houses and these people will feed them, will take care of them, will make sure that their health is as good as possible, there are also downsides too from the perspective of evolution and biology because we restrict their breeding or we restrict their social interaction.

It's not that dogs are necessarily thinking through this on an individual level, but on a species scale, if we're going to say, "Is this strategy effective?" we've already talked about the fact that dogs far outnumber wolves worldwide and they seem to, in terms of biological population numbers, be thriving, so they're definitely doing something right. So, whether we want to interpret that as lazy or less clever, you know it's working for them. In some ways, it's just a matter of not which animal or which species is more intelligent. It's a matter of which strategies or which patterns are most effective for a given species depending on their evolutionary history and those environmental constraints.

In many ways, the dogs are doing what works for them and the wolves are doing what works for them or has worked for them in the past. So, it's possible for both species to be doing something that is really brilliant but just specific to their individual niche.

Jesse: I assume you've probably heard about a Russian study, this was done, I think, mid-20th century. A Russian scientist that selectively bred foxes to domesticate them.

Dr. Clive Wynne: You're talking about Dmitry Belyayev.

Jesse: Yes, I am.

Dr. Clive Wynne: Very, very famous experiment, but yes, he did exactly that. Starting in 1959, Belyayev selected, in each generation, the roughly 5% of friendliest foxes, and these were foxes living in cages, they came from the fur trade. The friendliest 5% of foxes were selected to become the parents of the next generation, and all they did was they walked up to the cages and they recorded how the fox reacted, and generally speaking, a wild-type fox reacts with fear, and then if you actually stick your hand inside, it will dart out and bite you, and gradually, even within four or five years, they started finding that some of the foxes were becoming friendlier, that they would wag their tails like dogs when people came close to their cages. I usually describe it by saying he started in 1959, Belyayev died in 1986, and by the time he died, all the pups, all the foxes were very friendly towards human beings.

I've been there and I've seen these animals, and it's a quite astonishing experience because they're living outdoors in cages, just like they always did. They are not hand-reared, although people do come by and interact with them a little bit, and yeah, when you go up, they start trembling with excitement as a human gets closer. Now, open the cage, they more or less leap into your arms. It's quite an amazing experience, it really is, and a really powerful demonstration of what selection can do.

Jesse: It worked so well. Why don't we do this with more breeds of animals?

Dr. Clive Wynne: Well, there are a couple of levels to that. Wild is the population of animals was tens of thousands. Now, as big as he had a facility, tens of thousands of foxes. So, that's one part. The other part is that selection is a euphemism for killing animals, because it's not as if they had a massive retirement home for all these foxes that they didn't feel were good enough to breed from. They slaughtered them. I mean, it was expensive keeping them alive, they had to be fed meat. So, every autumn, they decided who would be bred from, and the rest, they slaughtered.

I think a more reasonable question is, given that people breed dogs, why don't we breed for the things that really matter? Why don't we breed for a gentle temperament, for a good companion? Why do we only breed for the appearance of the animal? That, I think, is a more reasonable question. As far as there is breeding going on, why do we breed for the things that we breed for?

Jesse: This is going to call for some speculation, but the level of friendliness that he wound up within those foxes, or the level that we see in dogs now, has that been pushed as far as it could be? Is there a genetic capacity for a certain amount of friendliness and we've pushed friendly as far as friendly can go, and there's not really an upper limit beyond that? Or, might there be a higher ceiling, we still haven't seen the world's friendliest dog?

Dr. Clive Wynne: That's a really, really interesting question. It is, as you say, speculation, and I'd really like to be doing more research on this. My feeling is that the friendliest dogs are definitely as friendly as we need them to be, and yet, it's clear that there is still vast phenotypic variability in that dimension, that there are dogs that are much, much less friendly, and those of us that love dogs, we must be careful not to lose track of the fact that dogs do cause immense distress in human societies.

The data I have are at least a decade out of date, but the most recent peer-reviewed survey estimated that 13,000 people in the United States go to emergency rooms every day because they've been bitten by dogs.

Jesse: You're kidding me. 13,000 a day?

Dr. Clive Wynne: Of course, behavior is a very complex phenotypic trait. A lot of these dogs that bite people, they may well be perfectly pleasant dogs in principle, but they've had bad life experiences that have set them up to be difficult to have around people. So, it's not as though breeding would fix everything, but as I said earlier, we do breed dogs. We breed dogs solely on their appearance, and that seems such a missed opportunity. We could be breeding for temperament.