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Archive for the ‘dog domestication’ Category

One of the great exercises on the internet among those who wish to be taken seriously as “dog people” is to say that dogs are not wolves. In one sense, they are quite right. Dogs are not wild canids, and they are certainly not the mostly fearful and reactive wolves of the middle latitudes of Eurasia and North America.

But in another broader sense, they are dead wrong. I’ve been following this debate for some time. At one time, there was a great emphasis on the so-called Canis variabilis that were contemporaries with Homo erectus at the Zhoukoudian cave system in China. The remains date to 500,000 years ago, and it’s quite a leap to say that Homo erectus began dog domestication.

It should be noted now that Canis variabilis is no longer an accepted scientific name for these early wolves. They have since been reclassified as a subspecies of the Mosbach wolf (Canis mosbachensis). Their new name is Canis mosbachensis variabilis, and although the Mosbach wolf is ancestral to the modern gray wolf, the Chinese subspecies is now not regarded as leading to the modern one.

So this idea that these Chinese specimens are ancestral to the domestic dog is quite faulty. Even if we were to say that Canis mosbachensis were the ancestor of dogs, we would have a real problem on our hands. The Mosbach wolf disappears from the Eurasian fossil record no later than 300,000 years ago, when it was replaced by modern gray wolves. The earliest domestic dog that has been proposed dates to 33,000 years ago in the Altai Mountains.

Somehow, you have to get a species that went extinct hundreds of thousands of years before the formation of the earliest domestic dog to become its ancestor. The chronology makes no sense.

Now, we do have some ancient mitochondrial DNA of a Siberian Canis cf. variabilis that appeared to show a connection with the origins of the domestic dog. This specimen is probably a ate surviving Siberian variant of the Mosbach wolf, and it is possible that the reason for this mitochondrial DNA similarity is that domestic dogs have a mitochondrial DNA lineage that very close to this extinct wolf. The real problem with this study is it is a mitochondrial DNA study, and if we could somehow get a full genome comparison from these remain, which would not be easy, then we could get a better picture of how the Mosbach wolf relates to wolves, domestic dogs, and coyotes. Yes, the discovery that gray wolves and coyotes shared a common ancestor only around 50,000 years ago means that coyotes descend from the Mosbach wolf as well.

So when you see someone claiming that Canis variabilis is wild Canis familiaris, just understand that this person hasn’t looked at the most recent literature on these Middle Pleistocene wolves. But I’ve seen this repeated enough that I do think I need a place on this blog where I can easily link to the problems with this assertion

The real problem with all of this is that in dogs, at least in the English speaking world, there is a real problem with phylogeny denial. So many people are caught up in this “dogs are not wolves” idea that they invest lots of mental gymnastics in trying to create another wild ancestor for the domestic dog.

So many people got worked up with the discovery that no extant population of gray wolf is ancestral to the domestic dog that they had to make it about how dogs were not derived from wolves.

Again, the gray wolf species is at least 300,000 years old, and no one has found a relationship between dogs and wolves that posits their divergence as being greater than 33,000 years. There is an old mitochondrial DNA estimate that is largely not accepted that puts their split between dogs and wolves at something like 135,000 years ago, but that’s still after the gray wolf existed as a species.

So let’s talk about why saying dogs are not wolves is an exercise in phylogeny denial:

One of the implications of our modern Darwinian synthesis is monophyletic descent. All organisms derive from ancestors, and it is impossible to evolve outside one’s ancestry. If we were to go back in time to see when the most recent common ancestor of dogs and gray wolves, you would have a hard time describing that ancestor as anything other than a form of Canis lupus.

Dogs have evolved through their Canis lupus ancestor, just as modern wolves have evolved through theirs. It is accurate to say that domestic dogs are not derived from extant wolves, but it is not accurate to say that dogs did not derive from wolves. It is also not accurate to say that dogs are a different species from Canis lupus, because dogs are still part of a Canis lupus lineage.

Further, we have lots of data about the extensive gene flow between dogs and wolves in Eurasia. We know that livestock guardian dogs in the Republic of Georgia have exchanged genes fairly extensively with wolves. But we now have data that shows an extensive gene flow between domestic dogs and wolves across Eurasia.

So dogs and wolves are continuing to exchange genes. They are not becoming reproductively isolated from each other in a way that would lead to speciation, even now.

I’ve never understood why this line of thinking has ever been popular, except that wolves people have indeed abused dogs under the assumption that their social systems are much like those of captive wolves. Further, it is quackery of the worst order to assume that dogs should be fed only full raw carcasses of meat because that is what wolves eat.

But those problems are not adequately addressed by promoting another scientifically dubious prospect. Dogs do behave somewhat differently from wolves, but that is because dogs are domesticated. Wolves behave differently because they are a wild form, and as a wild form, they have undergone a selection for extreme timidity and wariness as we have tried to wipe wolves off the face of the earth.

The argument that dogs are part of Canis lupus is well-supported by science. Indeed, an analysis of gray wolf, domestic dog, and dingo genomes revealed that creating a separate species for the dog, the dingo, or for both would make the entire species polyphyletic and thus not in keeping with Neo-Darwinian principles.

So it is scientifically correct to say that dogs are wolves, but one should say that dogs are domesticated wolves. And just leave it at that.

And drop the phylogeny denial.

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Mark Derr has been writing critiques of the Coppinger model of dog domestication for decades. His best known work on the subject matter is How the Dog Became the Dog, but his ideas can be read in a more succinct place at this article at The Bark (but do buy the book!).

Derr recently posted about Jung and Pörtl’s “Active Social Domestication Model” on his blog at Psychology Today.

His analysis is worth your time to read. He largely agrees with this model, but he contends that it needs to be placed in a larger framework of Derr’s own work and that on Wolfgang Schleidt and Michael Shalter, which is linked on Jung’s website.

Derr contends that Jung and Pörtl’s ideas need to be placed in this line of scholarship to which I’d also add the work of Darcy Morey and Pat Shipman. They don’t agree with each other on some important particulars, and they may have quibbles with this new model. But both scholars have been publishing outside of the Coppinger model for quite some time.

What I find most interesting is how this scholarship is pretty well-known outside of the English-speaking countries, but in the US and the UK, the generally accepted model by virtually everyone is the Coppinger model. Part of it may be that North America is home to wolves that are not particularly admixed with dogs. Indeed, they are probably the most “pure” wild wolves anywhere in the range of Canis lupus. And Great Britain and Ireland have no wolves, and there is no chance of any wolves coming back to those islands, at least by their own volition.

However, in Germany and Russia, wolves are admixed with dogs, and in the case of Germany, it is not at all impossible to see wolves living near large urban centers.

So they have a much more practical understanding of what it is like to live near wolves that have quite a bit of gene flow from domestic dogs, and they are less likely to buy into models that see dog and wolf as fundamentally distinct entities.

North Americans are much more accepting of a dichotomy model, and we have a hard time with gene flow between Canis populations. Our laws want hard and fast species, but the thing about Canis is that none of them are hard and fast species.

So it is easy for North Americans to posit that wolves are unable to be domesticated, because modern North American wolves (for the most part) are reactive and timid predators that do kill both dogs and coyotes they find on the trail. They do, but they also do the same with other wolves. And sometimes they mate with those wolves, just as they will mate with dogs and coyotes.

The Coppinger model requires an assumption that all wolves living in history and in the present are these shy timid ones, but that’s not what the historical record shows. And it is certainly not what is seen on Ellesmere or Baffin Island, where the wolves have never been persecuted by man.

The Coppinger model requires us to create the gray wolf as a Neanderthal dog in which it is big in size, big-brained, and meant to hunt only large prey, and posit the dog as the modern human with a smaller brain and more flexible diet.

We need a model that can place the origin of dogs before the Mesolithic, and this Active Social Model goes along way in that direction.

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I finally got around to watching Alpha, a film that depicts a fictionalized account of dog domestication. It is set 20,000 years ago in Europe, which means that it posits a European origin for the domestic dog, and because of this early date, it sets domestication in the time of Paleolithic hunter-gatherers.

The events in the film are backed in at least some of the literature on dog domestication. The oldest dog subfossil remains in existence that are not hotly debated as to belonging to a dog and not a wolf are the Bonn-Oberkassel dog, which dates to around 14,000 years ago. Yes, that’s about 6,000 years later than the events in Alpha, but we do have that paper positing European origins for the domestic dog that suggests an even older domestication event on that continent.


I should note right now that I remain agnostic whether dogs originated in Europe or Central Asia. Both are likely candidates based upon the best genetic data. I am open to there being two domestication “events,” but other than that one well-publicized paper, this hypothesis has not been well-received.

So it is potentially possible for the events in Alpha to be in keeping with some of the literature on dog domestication.

The film’s protagonist is Keda, who speaks a language that is called Solutrean, which is the name archaeologists have given to an industry culture in some parts of Paleolithic Europe. Because of the similarity between spearpoints from this Solutrean culture and some aboriginal North American peoples from roughly the same time period, some experts posited that European hunter-gatherers came across the North Atlantic following marine mammals along the ice flows, suggesting a European origin for some North American native people. Of course, this hypothesis has been dumped in light molecular data that show a Siberian origin for the indigenous people of the Americas.

Keda is the son of a Solutrean chief who wants his son to be a powerful and skilled hunter of big game, especially steppe bison, which are his people’s predominant prey species. Keda, though, is a bit soft with quarry. He refuses to finish off a wild boar that has been speared, and his father takes great umbrage with his temerity when it comes to the kill. But this is Keda’s first big hunting expedition, and his father really wants to teach his son the ways of his craft.

This world is not meant for those who cannot be crafty and tough. While sitting at a campfire, a cave lion absconds with one of the men. A memorial cairn is placed where the lion took the man, and they move on in search of meat in the hoof in a way that shows they accept their mortal fates in such a hostile environment. So Keda’s softness and excessive empathy might not be well-matched for such a lifestyle.

The hunting expedition reaches its climax when tribesmen and their close allies come across a herd of steppe bison. They stalk them in close, and they use their spear throws to drive them towards a cliff. Many fall off the cliff and die, and the Solutrean tribes can have their meat and hides and bones for another year. However, as they drive the bison off the cliff, one unusually recalcitrant one charges Keda and lifts him up with its horns and throws him off the cliff. He falls to a rock outcropping, where the tribe is forced to leave him for dead. A cairn is left in his memory on the cliff face, and his father and the hunters leave him to the ages.

It is at this point that film begins to play around with artistic license. Keda awakes when a griffon-type vulture tries to scavenge his carcass, and when Keda realizes that he is just resting on a ledge, he tries to climb down the steep cliff side with his badly injured leg. At that point, it starts to rain and the ravine below the cliff fills with water. He then jumps into the torrent below. Miraculously, he survives the fall and the rushing water, which I found a bit implausible. He then put his wounded leg back in order and begins looking around for a bit of food and shelter.

While he limps around, a pack of wolves shows up, but he manages to fight them off with the spearheads he’s carrying on his clothing and escape in a tree. He badly injures one of the wolves, which lies wounded beneath the tree.

I should note here that I am quite skeptical that Pleistocene wolves were particularly dangerous to people. As I’ve noted before, the wolves of Ellesmere and Baffin Island, which have never been intensely persecuted, are unusually curious and socially open with people. It seems to me that Eurasian wolves living 20,000 years ago would have had a similar curiosity about people, and thus, they would have been relatively easy for people to habituate them to our presence. I don’t think that an animal that was a much a threat to people as cave lions would have been trusted at all, and there would have been little of the empathy between people and wolves that could have led to any kind of partnership.

The empathy that Keda showed the boar, though, begins to cast upon the injured wolf. He muzzles the wolf and carries it to a cave, where he puts maggots on its wound to eat out any infection. He feeds the wolf a bit of the rabbit he manages to kill, and although the wolf is growling and surly through their initial interactions, the wolf eventually comes to trust Keda and within just a few scenes becomes as tame as any dog. Again, this is artistic license, but I think even those socially open wolves from the Pleistocene would still have had clearly-defined boundaries. They might have been friendly with people, but it is unlikely that they would have become that trusting at the first point of contact.

However, this part of the film does fit nicely with the recently posited Active Social Domestication Model in which human social interactions with wolves are the main catalyst behind creating the domestic dog. This model is relatively new, but it has a lot of explanatory power, especially when compared to the Coppinger Model, which just posits that scavenging wolves in at the middens Neolithic camps begat neotenic village dogs that were later selected for their working and hunting abilities and became the breeds of dog we have today.

Keda eventually realizes that the wolf is not going to leave his side, so he begins to show it even more empathy. He gets an idea that he could train this wolf to help him the hunt, and there are several scenes where he teaches the wolf to do commands. I doubt that this happened very much early on the domestication of the wolf, especially if we are to assume that humans and wolves developed a hunting symbiosis.

Indeed, the way Keda hunts with the wolf Is awfully unlikely. He uses the wolf to herd and flush wild boar, which he kills with a spear. Wolves can hunt wild boar that way, but it seems to me that the best way to use a wolf is as a “bay dog,” in which the wolf circles and distracts the quarry, holding it in one place so that a spear can be thrown.

Keda names the wolf “Alpha,” though he uses the Solutrean word for the term, and the two begin their journey to Keda’s home grounds. On their way, the man and wolf develop a tight bond. They play at the lake together, just the same way we would with our own dogs.

One night, a pack of wolves shows up at Keda’s campsite, a black wolf lures Alpha away from Keda. The black coloration is interesting, because it is quite rare in modern European wolves. It has only been introduced to wild wolves in modern times through crossing with dogs, including in North America where it was introduced to wolves from a dog living in either the Yukon or Northwest territories several thousand years ago. What we do know, though, is that this black coloration, which is conferred in wolves and is most dog breeds through a dominant allele, originated first in the population that led to domestic dogs.

As Keda makes his way back, the Pleistocene winter sets in. He now must travel without much food through the driving, blinding snow. Through a series of misadventures, he finds himself falling through the ice on a lake, and Alpha hears his distress and runs to rescue. The whole scene where the wolf comes to rescue Keda from the ice requires lots of artistic license, but it is visually spectacular.

Alpha and Keda are reunited and begin their long journey back to the home grounds. On their way, a pack of cave hyenas (a type of Pleistocene spotted hyena) chases them into a cave. Alpha and Keda await the hyenas in the cave. The snow piled up on the entrance of the cave quakes with their footsteps, but they do not enter. We soon learn the reason for their reluctance, a cave lion has been lurking deep with in the recesses of the cavern. It charges Keda and Alpha. Alpha fights the lion bravely, and Keda takes a deep breath and throws the spear, hoping it hits only the lion. It does, and Alpha survives, though pretty badly wounded. The lion provides some sustenance, and Keda and Alpha continue to make their way to the home grounds.

When Keda arrives home, he is quite ill, and he shows up with a very sick wolf on his mother and father’s doorstep. I can only imagine what it would have been like if such a scene had occurred in real life. If these people had no concept of partnering with a wolf, I bet their first compulsion would have been to club the wolf in the head for meat and fur. But Keda tells them they must care for Alpha too.

In the final scene, Keda is healed from his illness, and he sees a neonatal wolf puppy being held up by a priestess in an induction ceremony to the tribe. We then see Alpha nursing a litter of puppies. So, it turns out that after 90 minutes of film, we learn that Alpha is a female wolf. I wish there had been some mention the wolf’s sex earlier in the film, because I was honestly not prepared for the puppies.

The father of the puppies was apparently the black wolf, because one of the puppies is black, and thus, this detail would fit with the black coloration originating in the population that led to domestic dogs. The puppies grow up in the Solutrean tribe, and the final image of the film is the Solutrean hunting party going out on a hunting expedition with their wolves walking among them.

I will give this film props for doing quite a bit of research on some of the literature that puts dog domestication in the Paleolithic hunter-gatherer societies of Eurasia. It posits a possible origin for the domestic dog that came from the coming of age story of one of these Pleistocene hunters.
However, the actual domestication of the dog from wolves in these societies had to have been a bit more complex than the film states. In one flashback of the film, Keda’s father discusses wolves howling around their camp and how men must behave like wolves if they are to be good hunters. Of course, the father uses the toxic memes of alpha wolves in both the canid and human society. I honestly could have done without either.

But this flashback does hint that these hunter-gatherer people had some empathy with wolves, and it is this empathy that humans had with wolves that allowed us to form this partnership. I am reminded very much of Schleidt and Shalter’s hypothesis that wolves showed man how to hunt ungulates in Eurasia more effectively.

Humans and wolves have sort of convergently evolved as cooperative hunters, and it is very likely that humans would have seen much of themselves in wolves. Plus, if Pleistocene wolves behaved like the wolves of Ellesmere, humans would not have feared them in the way they would have feared cave lions or hyenas. This is a large social carnivoran that hunts big game but does not typically target us, and those features provided just enough space curiosity, empathy, and even reverence to develop.

I think that the hunting symbiosis hypothesis for dog domestication is essentially correct, but I don’t think it came about because someone managed to tame a wolf and hunt with it. I think it simply happened because humans, as opportunistic hunters and scavengers, figured out that following wolves was a great way to get good fatty meat. Wolves constantly test ungulates by harrying them. Those that are healthy stand and fight. Those that are weak run. The wolves usually kill the weak ones. The healthy ones that stood to fight would have been easier targets for the spear, and the healthy ones are full of fat that our big brains need.

So we would have figured out that if we followed wolves we could get the good meat we needed to survive, and the wolves likely would have figured out that we were the ticket to getting an easier meal. We probably drove the wolves off the carcasses at first, but we probably left enough meat for the wolves get a lot of reward for their effort.

Further, reliance upon human societies would have allowed one wolf reproduction strategy to operate quite well. In wolf packs, a single mated pair does all the approved breeding. If another female gets pregnant, the main breeding female (sometimes called the alpha female) kills the puppies of the other female or steals them to add to her litter. Usually, this main breeding female comes in heat first, and her older puppies easily outcompete the other female’s pups.

But these females do get pregnant. That’s because on the outside of the pack territory, there are unpaired males roaming about. These females are usually the daughters of the main breeding pair, and because wolves have some inbreeding avoidance behavior and because their mother will beat them down if they try to mate with her mate, they will often try to mate with these unpaired males that roam outside the pack

One notable male wolf in Yellowstone, the so-called “Casanova,” wound up living most his life as an unpaired male that mated with these unpaired females. In the early days of the Yellowstone reintroduction, the main breeding females of several packs allowed these unpaired females to raise their litters. Prey was abundant and naïve, so there was no need to kill the pups of these females.

Keeping a single litter is a lot of work for a wolf pack, so there is a very strong need for the litters tying them down each year to be reduced to one or none. When you have more prey, these pressures are released.

It is very possible that humans provided a space for that Casanova strategy to work more often. Some of the first wolves that may have hooked up with humans on a more intimate basis could have been females that wanted to have their litters away from their murderous mothers, and humans could have felt empathy towards these female wolves, tossing them food and protecting them from predators while they raised their litters. Humans could have provided a space for wolves that bred this way to reproduce efficiently, and if you’re just mating with a male and not engaging in all the social suppression of estrus and litter culling and purloining behavior, genes can spread much more rapidly. Perhaps the wolves that had lessoned genetic tendency toward pair bonding behavior became the basis for the domestic dog, and these genes wound up swamping the entire population of wolves that became domestic dogs, which is why pair-bonding behavior is uncommon in most domestic dogs

So basing the domestication story upon a female wolf is pretty wise.

My other quibbles with the film have more to do with the depth of characterization. I never really got to know Alpha as a wolf or a dog or anything. She was just a straight-up heroic figure, but I didn’t find the whole process of her transforming from a predator that would hunt humans to an extremely dog-like wolf particularly believable. I also wanted better CGI of the cave lions and hyenas. I am a bit of a Pleistocene mammal nerd, and I really wanted more of them. But they are like phantasmal entities that lurk in as agents of death and nothing more.
The writers did do quite a bit of homework on dog domestication, but I think they could have done more and pushed for an even more compelling narrative.

Finally, the “wolf” in the film is a Czechoslovakian vlcak, a breed of dog derived from Czechoslovakian working German shepherds and European wolves from the Carpathian Mountains. They were originally bred as an “improvement” to the working GSD of communist Czechoslovakia, but they never really got off the ground in that way. However, because they are mostly German shepherd and were selected hard for temperament, they are the most successful wolfdog breed ever produced. I do wonder, though, if people watching the film will realize that this breed is what was used to portray a wolf in the film. We are already going through a bit of a boomlet with Siberian huskies in North America, which is somewhat attributed to their wolfish features. If people do realize there is a breed of wolfdog that is recognized by many kennel clubs, then I can see this breed being mass-produced and sold to gullible people without much regard for temperament. This film gives the public this bit of information, then we could see lots of these dogs in shelters and pounds, which I’m sure no responsible breeders of vlcaks wants.

No, the performance of vlcaks in Alpha was not as compelling as Jed the wolfdog, but the public is now being exposed to this breed’s existence. It is something we need to think about very carefully.

I do give Alpha major props for trying to posit the origins of the dog within European hunter-gatherer societies and to give some credence to the Active Social Model for dog domestication, but in story-telling, I just couldn’t allow myself to follow that much artistic license with Keda’s miraculous escapes from danger.

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It’s not unusual for people who are trying to deny evolution or promote creationism or both, to come up with a common question:

“If evolution is true, then why don’t dogs have something that isn’t a dog every once in a while?”

This question would not be so much of a problem if we, who think we know better, would stop trying to create a species called Canis familiaris.

Canis familiaris made sense when we didn’t know what dogs were derived from, and it might have made sense if we thought there were hard and fast reproductive barriers between dogs and wolves.

But it turns out that they really aren’t such distinct animals. We’ve learned this when we’ve performed more complete assays of domestic dog and wolf genomes. Since then, we’ve found that the majority of Eurasian wolves have some domestic dog ancestry, and black wolves in North America got their black coloration as the result of a single cross with a black dog that mated with a wolf thousands of years ago in the Yukon or Northwest territories.

A recent genome comparison study of wolves and dogs that attempted to put together a phylogeny of the species clearly states:

[W]ithin the Old World clade, wolf and dog represent sister taxa. Therefore, suggestions that the dog or dingo are a separate species (Canis familiaris) (e.g., Crowther et al. 2014) would cause gray wolves to be a polyphetic taxon; and consequently, our results support dogs as a divergent subspecies of the wolf. This result has societal significance as legislation in some countries and regional governments consider wolves and dogs as distinct species restricting the possession, interbreeding, or the use of vaccines and medications in wolves or dog–wolf hybrids if they have only been approved for use in dogs. In this sense, analysis of evolutionary history informs law and veterinary practice, as dog lineages are nearly as distinct from one another as wolves are from dogs, and the justification for treating dogs and wolves differently is questionable.

The monophyly of the species is one thing that I think everyone should agree is worth preserving in any taxonomic system, but the genomes clearly show that if we create a special species for the dog or the dingo, we wreck the monophyly of Canis lupus.

I would also contend, perhaps a bit more controversially, that in light of a similar study of North American wolf-like canids’ genomes, that the coyote is also part of Canis lupus. This study found that gray wolves and coyotes have exchanged genes across North America and that gray wolves and coyotes last shared a common ancestor only around 50,000 years ago. That ancestor was probably an ancient Eurasian gray wolf that came into North America and evolved for a more generalist, jackal-like niche in the mid-latitudes of North America.

When someone claims that dogs are not wolves, they can only mean it in the same way that pugs are not Siberian huskies or that Great Danes are not dingoes. They are not wild Canis lupus, but they clearly are within that species, if we wish to keep the species monophyletic.

The reason why people want to claim a special species for the dog is because of Raymond Coppinger’s ideas still hold a lot of sway with people who wish to be learned about dogs. It’s not that everything that Coppinger said was wrong. It is what he was wrong about seems to be all that people know.

Coppinger argued that domestic dogs were obligate scavengers and thus must be placed as their own ecological species. An ecological species is the best argument for Canis familiaris. But it has limits for our understanding of evolution, and it can be turned into an absurd concept. For example, there are two sharp-tailed grouse subspecies that live in slightly different but adjacent habitat but do not readily interbreed. If we were to adhere to the same sort of species concept, then these two subspecies would have to be distinct species, even if it busted up the entire monophyly of the sharp-tailed grouse species.

Coppinger is ultimately quite wrong about the obligate scavenger status for domestic dogs. In India, for example, predation by feral and free-roaming domestic dogs is a major conservation issue. And Italian wolves are big time dump denizens. So both dogs and wolves can be predators or scavengers based upon available prey and refuse resources.

Because the ecological species concept is muddled when comparing wolves to dogs and keeping an arbitrary Canis familiaris species destroys the monophyly of Canis lupus, it would make more sense to drop Canis familiaris entirely.

One could raise dogs to Canis lupus familiaris, but Raymond Pierotti and Brandy Fogg have argued in their book, called The First Domestication: How Wolves and Humans Coevolved, that there is no set of behavioral, physical, or physiological traits that define all dogs as a taxonomic entity. They instead argue that we should just call them “domestic Canis lupus,” in which they also group the dingo, which is “feral domestic Canis lupus.

I remain agnostic about what we should call dogs, but Pierotti and Fogg’s quibbles are difficult to ignore. Perhaps we could have the subspecies for the dog, but there must be some acknowledgement that all we are doing is defining a domestic and feral population of a species.

If this blog post looks familiar, I wrote almost this exact same post in March, but I sometimes feel that I have to explain the very real scientific reasons why we don’t say that dogs are a unique species. It is not anti-science to do so, despite what Facebook dog experts tell you. If we want a monophyletic Canis lupus, then dogs have to be part of it.

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Gordon Buchanan hanging out with fully wild wolf named Scruffy on Ellesmere Island. These Ellesmere wolves and those of Greenland were recently found to be a very genetically distinct population of North American wolf.

Long-time readers of this blog know that I am particularly fascinated by studies on wolf DNA, and I was surprised that I missed this little gem that came out in PLOS Genetics last month.

The authors used 40 genome sequences of gray wolves, Great Lakes wolves, proposed Eastern and red wolves, and coyotes. The authors found further evidence to show that red, Eastern, and Great Lakes wolves are various mixtures of coyotes and gray wolves. The paper also found that all gray wolves derived in North America do derive from a single ancestral population and thus represent a single monophyletic clade within Canis lupus. 

The most interesting part of this paper though dealt with the genomes of wolves from the Queen Elizabeth Island, the famous arctic wolves, which are known for their white coats and curious nature around people.

The authors found that there were three distinct populations, which the authors define as East Arctic, West Arctic, and Polar.   The first two had some evidence of admixture with mainland gray wolves, but the ones defined as “Polar” did not. 

The wolves whose genomes came back that distinct were from Ellesmere and Greenland, which are the most northerly distributed of all North American wolves. The authors found that these wolves are relatively isolated from other wolf populations, and they do not have much genetic diversity.

These wolves have long fascinated me. They are curious and even socially open with people, and I think could give us a clue about how wolves could have hooked up with people in those Pleistocene days. 

But the discovery that they really are a genetically distinct population is also of great interest. Even more, we have full genomes from these wolves now, and maybe we can do a comparison study of these curious wolves that have never been intensely persecuted by man, normal gray wolves, and domestic dogs.  Maybe we can see what sorts of genes dogs and these polar wolves share that do not exist in other wolves, and maybe we could find out that my hypothesis is correct. 

This hypothesis is the one that states that the original wolves of Eurasia behaved more like these polar wolves than the timid and fearful wolves of lower latitudes. If these polar wolves share genes associated with tameness that are also associated with domestic dogs and their general behavior, then we might see evidence some evidence that the original wolf of Eurasia would have had the temperament that could have led to domestication.

But that will have to wait for another paper, which I am waiting for. 

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Wolves and coyotes working as sled dogs in Ontario in 1923. 

The world of dogs is full of ideas, and over the years, those ideas and their expositors have created several camps.  I have learned to keep my head down in most of these discussions about dog ideology, and yes, I learned it the hard way. But I know there are several idea with which I will lay out my own views, or at least critique what I think is an error.

It is hard to overestimate the work of Raymond Coppinger in forming the main ideas around modern dog science.  Coppinger was a biology professor at Massachusetts’s Hampshire College, and he proposed a particular dog domestication hypothesis. This is the model that lots of dog experts believe is correct, and this model also informs how they view the essential biology of dogs.

Coppinger’s domestication model relies heavily upon the work of a Soviet geneticist named Dmitri Belyaev. Belyaev was a Mendelian at the time of Lysenkoism, and he was banished a research facility in Novosibirsk, where he conducted domestication experiments upon silver-phase red foxes that were from fur farm populations. Belyaev selected for tameness using several criteria, and after so many generations, he produced foxes that had drop ears, less sexual dimorphism, large areas of white on their coats, curled tails,  and even multiple estrus cycles per year.

This suite of features very strongly resembles the traits we see in domestic dogs, and Belyaev thought of his experiments as a sort of controlled analogy to dog domestication. 

Coppinger took Belyaev’s ideas a bit further. Instead of seeing humans as actively domesticating wolves, Coppinger believed the whole process came from wolves scavenging near dumps near what became Neolithic settlements. These wolves evolved to become smaller and evolved smaller brains so they could live more easily on wastes, and these animals became the village dogs. Later, people would select for working and hunting behaviors in village, but dogs themselves were not domesticated for any purpose. They evolved from scavenging wolves.

The analogy that Coppinger saw in Belyaev is that he assumed that all wolves through all history had been the very timid paranoid wolves that are known in the lower latitudes of North America and Eurasia, and he thought that for wolves to become successful scavengers in such close proximity to humans that they would have undergone something similar to Belyaev’s selection.  Those that were less afraid of humans would be more likely to stand in dumps while humans were nearby, eating more of the easily procured food.

When I first started this blog, you can see echoes of Coppinger in what I wrote on dog domestication. I loved his 2001 book, but as I’ve read more about wolves and new studies on dog cognition. I’ve come to doubt many of his ideas. 

One of the biggest problems with Coppinger’s model is that the earliest dog remains that are not in contention as belonging to a dog are those of the Bonn-Oberkassel dog. It dates to 14,000 years ago in what is now Germany, and recent analysis showed that was actually a seven-month-old puppy that died of distemper. This dog existed in Europe thousands of years before the Neolithic cultural exchanges hit the region. That means the dog was created by hunter-gatherers of the Paleolithic, not in the Neolithic middens.

The other problem I have with Coppinger’s model is the assumption that all wolves through history are these fearful and often paranoid wolves that exist in much of North America and Eurasia. However, when one reads accounts of early explorers and settlers to North America, there are many accounts of curious and often socially open wolves approaching humans. Lewis and Clark’s diaries tell of luring a wolf in very close with a piece of meat and then killing it with a spear, and various other authors talk of wolves living very near native people’s camps and settlements, often crossing with the dogs. It is likely that our widespread persecution of wolves has culled out all this curiosity and tolerance of people in most extant wolves. Through our hunting, trapping, and poisoning campaigns, we have selected for wolves that are timid and shy, if not totally paranoid.

Further, we have wolves on Ellesmere and Baffin Island that have never been extensively hunted by humans, and these wolves are quite curious and tolerant of humans. (See Jim Brandenburg’s “White Wolf” and Gordon Buchanan’s “Snow Wolf Family and Me” to get an idea of how tolerant and curious these wolves are.) These wolves, though certainly adapted for life in polar conditions, are potentially a good model for what the original wolves of Eurasia were like when they first encountered our species. They were likely quite curious and socially tolerant as these wolves are, and it would have been easy for hunter-gatherers to form a relationship with them.

Several attempts to counter some of Copponger’s shortcomings have come to the fore in recent years. Darcy Morey and Rujana Jeger have posited shifting trophic strategies between wolves and hunter-gatherers, such that dogs evolved from wolves in hunter-gatherer societies and became apex predators with people, later becoming apex consumers with humans in the Holocene. Raymond Pierotti and Brandy Fogg have made a similar attempt in their First Domestication: How Humans and Wolves Coevolved. These two authors rely heavily upon ethnography of hunter-gatherer peoples or partially hunter-gatherer peoples and their complex relationship with hunting dogs and wolves.  The authors contend that these societies have the best framework for understanding how wolves might have been domesticated within a hunting symbiosis.

Recently, though, I came across a new model, one that offers a critique of Coppinger and encapsulates many of the ideas of Morey and Jeger and Pierotti and Fogg. It also posits a new theory of dog domestication called the Active Social Model of dog domestication. 

The authors of this model are Christoph Jung and Daniela Pörtl, and they posit a model that sees wolves and people in the late Pleistocene operating as predators that often worked together and showed each other some mutual respect. In this model, emotional bonds that existed between wolves and people were a major driving force behind the domestication of dogs, and this is the missing piece that explains why wolves were domesticated. Foxes, jackals, and hyenas have all been noted as scavenging near human settlements, but they have never attempted to form emotional bonds with people, unlike the aforementioned wolves of Ellesmere. 

I really like this model, because it actually does mention many things I’ve discussed on this blog. It allows for the less-than-timid, more socially open wolves of the High Arctic as a better model for Pleistocene wolf behavior than those from other more persecuted populations. It also allows for the concept of a potential hunting partnership between wolves and humans as the catalyst for domestication. 

As I noted before, I think the way humans capitalized upon wolves as hunting partners is that humans figured out that a very good way to kill fat healthy game was to follow wolves.  Wolves constantly test game.  If the quarry runs, it is usually unhealthy and will be easily run down, so the wolves’ instinct is to give chase. If game is healthy, it will stand and fight the wolves. 

The stand and fight behavior would give ancient hunter-gatherers a relatively stationary target for their spears, so wolves and humans learned that they could both easily bring down healthy prey if they made it stand and fight.

It is precisely how elkhounds, Karelian bear dogs, and big game laiki bay up moose and wild boar for the rifle shot.  The only difference is these dogs bark while the prey stands at bay.

Humans are big-brained, and our nutritional needs when living on a meat-based diet require quite a bit of fat. Being able to kill healthy prey in this way was a great way to get the fat we needed to power our large brains.

And it would have been to our advantage to hook up with wolves, and wolves would have had an easier job getting meat. They wouldn’t have to grapple so much with big dangerous prey. Our spears would do much of the work, and they would get some meat for their troubles.

This new active social domestication model allows for this sort of relationship to have been the process whereby humans and wolves hooked up. This relationship is far beyond the simple scavenger at the dump. Wolves were not the trash pandas of the Pleistocene. Instead, we had humans and wolves interacting with each other, and over time, these interactions led to the development of the dog.

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Man originated in Africa. The whole lineage of apes from which we and all the other human species descended was in Africa, a sister lineage to the apes that gave us the chimpanzee and the bonobo.

But man’s first domestic animal was not of Africa at all. The large pack-hunting wolf roamed the great expanses of Eurasia, and it was only when certain Eurasian hunters began to incorporate wolves into their societies that we began the process of domestication.

For nearly two million years, human ancestors and the ancestors of the wild dog lived throughout Africa.  There was never an attempt to bring these dogs to heel, and there was never attempt to reach out to that species.

The question remains of why African wild dogs were never domesticated, and part of the answer lies in their nervous nature. I am reminded of Martin Clunes’s A Man and His Dogs.  Clunes ended his two part documentary with a visit to Tony Fitzjohn’s African wild dog project, and at one point, Clunes is asked to pick up a tranquilized African wild dog, while making certain that the jaws are positioned well away from his body.  These dogs react and react quickly.

These dogs live as quite persecuted mesopredators in an intact African ecosystem that includes lions and spotted hyenas.  Yes, this animal that kills large game with a greater success rate than any other African predator is totally the underdog in a land so dominated by the great maned cat and the spotted bone-crusher.

Their lives must be spent hunting down quarry and then bolting down meat as fast as they can before the big predators show up to steal it.

The current thinking is the first African wild dog ancestor to appear in Africa was Lycaon sekowei. This species lived in Africa from 1.9 to 1 million years ago, which is roughly the same time frame in which the first human ancestors began to consume meat readily.  It was very likely that a major source of meat consumed by these ancestors came from scavenging.  Homo habilis has been des cribed as a very serious scavenger, as was Homo erectus.

Both Homo habilis and erectus were contemporaries of Lycaon sekowei, and one really thinks about it, these early humans would have been very interested in the comings and goings of the great predators. Of all the predators to drive off kills, it is obvious that a pack of wild dogs would be easier to drive off than just about any other predators that were evident in Africa at the time.

So for at least 1.9 million years, African wild dogs evolved knowing that humans of any sort were bad news.  They may have inherited an instinct towards antipathy toward humans, and thus, there never was any chance for us to develop relationships such as those that have been observed with wolves and hunter-gatherer people.

I think this played a a much bigger role in reason why man never tried to domesticate African wild dogs. One should also keep in mind that wolves in Eurasia were also mesopredators in that ecosystem. Darcy Morey and Rujana Jeger point out that Pleistocene wolves functioned as mesopredators in which their numbers were likely limited by cave lions, archaic spotted  hyenas, and various forms of machariodont. They were probably under as much competition from these predators as the ancestral African wild dogs were under from the guild of super predators on their continent.

What was different, though, is the ancestral wolves never evolved in an enviroment which scavenging from various human species was a constant threat, so they could develop behaviors towards humans that were not always characterized by extreme caution and fear.

We were just novel enough for wolves to consider us something other than nasty scavengers, and thus, we could have the ability to develop a hunting symbiosis as is described in Mark Derr’s book and also Pierotti and Fogg’s.

It should also be noted that African wild dogs do not have flexible societies. In wolf societies, there are wolves that manage to reproduce without forming a pair bond, simply because when prey is abundant, it is possible for wolves other than the main breeding female to whelp and rear puppies. These females have no established mates, and they breed with male wolves that have left their natal packs and live on the edges of the territories of established packs. In the early years of the Yellowstone reintroduction, many packs let these females raise their pups that were sired by the wanderers, and one famous wolf (302M) wound up doing this most of his life, siring many, many puppies.  I think that what humans did in their initial relationships with wolves was to allow more wolves to reproduce in this fashion, which opens up the door for more selective breeding than one would get from wolves that are more pair-bonded.

In African wild dogs, one female has the pups. If another female has puppies, hers are confiscated by the main breeding female and usually starve to death.

The wolf had the right social flexibility and the right natural history for humans form relationships with them, which the African wild dog was lacking.

 

 

 

 

 

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