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Posts Tagged ‘dog domestication’

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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P1050079

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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Very interesting concepts:

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kenya black-backed jackal

We think of interactions between predators as always antagonistic.  Meat is hard to come by, and if one comes by meat on the hoof, it is unlikely that the owner-operator of said flesh will give it up willingly.   Meat is a prized food source, and it is little wonder that most predators spend quite a bit of energy driving out competitors from hunting grounds.

Because of this antagonism, the domestication of wolves by ancient hunter-gatherers is difficult to explain. Indeed, the general way of getting wolves associated with people is see them as scavengers that gradually evolved to fear our species less.

This idea is pretty heavily promoted in the dog domestication literature, for it is difficult for experts to see how wolves could have been brought into the human fold any other way.

But there are still writers out there who posit a somewhat different course for dog domestication.  Their main contentions are that scavengers don’t typically endear themselves to those from which they are robbing, and further, the hunter-gatherers of the Pleistocene did not produce enough waste to maintain a scavenging population of wolves.

It is virtually impossible to recreate the conditions in which some wolves hooked up with people. With the exception of those living on the some the Queen Elizabeth Islands, every extant wolf population has been persecuted heavily by man. Wolves generally avoid people, and there has been a selection pressure through our centuries of heavy hunting for wolves to have extreme fear and reactivity. It is unlikely that the wolves that were first encountered on the Mammoth Steppe were shy and retiring creatures. They would have been like the unpersecuted wolves of Ellesmere, often approaching humans with bold curiosity.

As I have noted in an earlier post, those Ellesmere wolves are an important population that have important clues to how dog domestication might have happened, but the truth of the matter is that no analogous population of wolves or other wild canids exists in which cooperation with humans is a major part of the survival strategy. The wolves on Ellesmere are not fed by anyone, but they don’t rely upon people for anything.

But they are still curious about our species, and their behavior is so tantalizing. Yet it is missing that cooperative analogy that might help us understand more.

I’ve searched the literature for this analogy. I’ve come up short every time. The much-celebrated cooperation between American badgers and coyotes is still quite controversial, and most experts now don’t believe the two species cooperate.  Instead, they think the badger goes digging for ground squirrels, and the coyote stand outside the burrow entrance waiting for the prey to bolt out as the badger’s digging approaches its innermost hiding place in the den. The coyote gets the squirrel, and the badger wastes energy on its digging.

But there is a story that is hard to dispute. It has only been recorded once, but it is so tantalizing that I cannot ignore it.

Randall Eaton observed some rather unusual behavior between black-backed jackals and cheetahs in Nairobi National Park in 1966.

Both of these species do engage in cooperative hunting behavior. Black-backed jackals often work together to hunt gazelles and other small antelope, and they are well-known to work together to kill Cape fur seal pups on Namibia’s Skeleton Coast. Male cheetahs form coalitions that work together to defend territory and to hunt cooperatively.

However, the two species generally have a hostile relationship. Cheetahs do occasionally prey upon black-backed jackals, and black-backed jackals will often mob a cheetah after it has made a kill, in hopes of forcing the cat to abandon all that meat.

So these animals usually cannot stand each other, and their interactions are not roseate in the least. Eaton described the “normal interaction” as follows:

The normal interaction between these two predators occurs when the jackals hunt in the late afternoon and come into a group of cheetahs. The jackals, often four or five, are normally spread out over several hundred yards and maintain contact by barking as they move. When cheetahs are encountered by one of the jackals, it barks to the others and they all come to the cheetahs, sniffing the air as they approach apparently looking for a kill. If the cheetahs are not on a kill, the jackals search the immediate area looking for a carcass that might have just been left by the cheetahs. If nothing is found, they remain near the cheetahs for some time, following them as they move ; and when a kill is made the jackals feed on the leftover carcass. If the cheetahs have already fed and are inactive and if a carcass is not found nearby, the jackals move on.

However, Eaton discovered that one particular group of jackals and one female cheetah had developed a different strategy:

At the time I was there in November, 1966, one area of the park was often frequented by a female cheetah with four cubs and was also the territory of a pair of jackals with three pups. The jackal young remained at the den while the adults hunted either singly or together. Upon encountering the cheetah family, the jackals approached to about 20 yards and barked but were ignored except for an occasional chase by the cubs. The jackals ran back and forth barking between the cheetahs and a herd of Grant’s gazelles (Gazella granti) feeding nearby. The two jackals had gone on to hunt and were almost out of sight by the time the adult cheetah attacked two male Grant’s gazelles that had grazed away from the herd. The hunt was not successful. The jackals took notice of the chase and returned to look for a kill ; it appeared that they associated food with the presence of the cheetahs and perhaps with the chase.

One month later, while observing the same cheetah family, I noticed that the entire jackal family was hunting as a group. The cheetah and her cubs were about 300 yards from a herd of mixed species. This same herd had earlier spotted the cheetahs and given alarm calls. The adult cheetah was too far away for an attack,there was little or no stalking cover and the herd was aware of her presence. The cheetahs had been lying in the shade for about one-half an hour since the herd spotted them when the jackals arrived. Upon discovering the cheetahs lying under an Acacia tree, one of the adult jackals barked until the others were congregated around the cheetah family. The jackal that had found the cheetahs crawled to within ten feet of the adult cheetah which did not respond. The jackal then stood up and made a very pneumatic sound by forcing air out of the lungs in short staccato bursts. This same jackal turned towards the game herd, ran to it and, upon reaching it, ran back and forth barking. The individuals of the herd watched the jackal intently. The cheetah sat up and watched the herd as soon as it became preoccupied with the activity of the jackal. Then the cheetah quickly got up and ran at half-speed toward the herd, getting to within 100 yards before being seen by the herd. The prey animals then took flight while the cheetah pursued an impala at full speed.

Upon catching the impala and making the kill, the cheetah called to its cubs to come and eat. After the cheetahs had eaten their fill and moved away from the carcass, the waiting jackals then fed on the remains.

Eaton made several observations of this jackal family working with this female cheetah, and by his calculations, the cheetah was twice as successful when the jackals harassed the herds to aid her stalk.

Eaton made note of this behavior and speculated that this sort of cooperative hunting could have been what facilitated dog domestication:

If cheetah and jackal can learn to hunt mutually then it is to be expected that man’s presence for hundreds, of thousands of years in areas with scavenging canines would have led to cooperative hunting between the two. In fact, it is hard to believe otherwise. It is equally possible that it was man who scavenged the canid and thereby established a symbiosis. Perhaps this symbiosis facilitated the learning of effective social hunting by hominids. Selection may have favored just such an inter-specific cooperation.

Agriculture probably ended the importance of hunting as the binding force between man and dog and sponsored the more intensive artificial selection of breeds for various uses. It is possible that until this period men lived closely with canids that in fossil form are indistinguishable from wild stock (Zeuner, 1954).

Domestication may have occurred through both hunting symbiosis and agricultural life; however, a hunting relationship probably led to the first domestication. Fossil evidence may eventually reconstruct behavioral associations between early man and canids.

Wolves are much more social and much more skilled as cooperative hunters than black-backed jackals are. Humans have a complex language and a culture through which techniques and technology can be passed from generation to generation.

So it is possible that a hunting relationship between man and wolf in the Paleolithic could have been maintained over many generations.

The cheetah had no way of teaching her cubs to let the jackals aid their stalks, and one family of jackals is just not enough to create a population of cheetah assistants.

But humans and these unpersecuted Eurasian wolves of the Pleistocene certainly could create these conditions.

I imagine that the earliest wolf-assisted hunts went much like these jackal-cheetah hunts. Wolves are always testing prey to assess weakness. If a large deer species or wild horse is not weak, it will stand and confront the wolves, and in doing so, it would be exposing itself to a spear being thrown in its direction.

If you’ve ever tried a low-carbohydrate diet, you will know that your body will crave fat. Our brains require quite a bit of caloric intake from fat to keep us going, which is one of those very real costs of having such a large brain. Killing ungulates that stood to fight off wolves meant that would target healthy animals in the herds, and healthy animals have more fat for our big brains.

Thus, working together with wolves would give those humans an advantage, and the wolves would be able to get meat with less effort.

So maybe working together with these Ellesmere-like wolves that lived in Eurasia during the Paleolithic made us both more effective predators, and unlike with the cheetah and the black-backed jackals, human intelligence, language, and cultural transmission allowed this cooperation to go on over generations.

Eaton may have stumbled onto the secret of dog domestication. It takes more than the odd population of scavenging canids to lay the foundations for this unusual domestication. Human agency and foresight joined with the simple cooperative nature of the beasts to make it happen.

 

 

 

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atila and the wolf
Photo by Tanja Askani.

In paleontology, a group of scholars exists largely on the fringe of the discipline. No matter what evidence is provided, they find some way to pump out a paper that says that birds cannot be dinosaurs. An established scholar or two will the publish and beat them down, but there is still an idea in the public mind that there is a debate between dinosaur experts about whether birds are a specific type of theropod dinosaur.

These scholars are known as BAND (“birds are not dinosaurs”), and they do get the attention of the popular press, even if ignored by the mainstream scholarship.

I’ve noticed in that in all my years writing about dogs and their taxonomy that there is a similar group in this sphere as well.  The difference is this group had the backing of one of the leading authorities on dogs in the world, Raymond Coppinger.

Coppinger was certain that dogs had to be classified as Canis familiaris, based upon a very crude ecological species concept. Village dogs that scavenge off human civilization hold a different niche than pack-hunting wolves, ergo, they are different species. Never mind that if we applied that same standard strictly, Arabian wolves, which scavenge a lot and don’t often hunt large prey, would be a different species from arctic wolves or any of the moose, elk, or bison-hunting wolves we have in North America.

If we are to adhere to cladistic classification, though, it is virtually impossible to create arbitrary species for dogs. The reason is best summed up in this paper that compared genomes of many wolves and a few dogs that have origins on different continents. The authors concluded:

 [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.

That pretty much should end this discussion. What these authors found and has been discovered in other papers is that dogs descend from a ghost population of gray wolves, Eurasian gray wolves, to be exact.

Lots of other experts agree with this assessment. Darcy Morey, an archaeologist with a great expertise in the study of Pleistocene wolves and early domestic dogs, has the address for his website as “dogsarewolves.com.” He and Rujana Jeger have formulated a conceptual framework of dog domestication that is quite unique. Basing their model upon trophic strategies on behalf of the wolves and shifting perceptions of humans, the authors contend that wolves that became dogs attached themselves to people. These early humans were often already acting as the apex predators in the ecosystem of the Pleistocene, and the wolves that did join up with people were able to take advantage of this niche.  Pleistocene wolves were not operating as apex predators in a faunal guild that included machairodonts, cave lions, cave bears, and Pleistocene spotted hyenas, but when those animals became extinct, the wild wolves became the apex predators of Eurasia.  The wolves that hooked up to people joined humanity in agricultural societies and joined us as apex consumers. When humans began to domesticate other livestock,  wild wolves were seen as competitors and killed off.

The idea that dogs are not wolves does have some currency, especially if you’re quite stuck on Southeast Asian origins for domestic dogs. Vladimir Dinets believes that wild Canis familiaris was some kind tropical Southeast Asian canid that was related to but not descended from Canis lupus.  There is still a massive debate as to where dogs originated, and it should be noted that there are as many good papers that have concluded European or Central Asian origins as have suggested as Southeast Asian origins.

The reason you would go for wild Canis familiaris in Southeast Asia as the ancestor is that Southeast Asia is one of the few places in Eurasia that never has had gray wolves living there. In these schools of thought, much emphasis is placed upon Canis variabilis a possibly being the wild ancestor. Of course, Canis variabilis disappeared from the fossil record 300,000 years ago, and no serious scholar thinks dogs diverged from wolves that early.

The real problem is the genetic closeness between wolves and dogs, and that same genome comparison study mentioned earlier shows a significant gene flow between wolves and domestic dogs. Up to a quarter of all Eurasian wolf genomes likely have some dog ancestry, and in East Asian wolves, the dog component of their genome can be as high as 20 percent. In European and Middle Eastern wolves, the dog component can be as high as 25 percent.

The only thing that keeps dogs from swamping the Eurasian gray wolf population with dog genes is the reproductive and territorial behavior of wolves. Wolves generally allow only one female to raise her pups. Wolves generally kill dogs that wander onto their territories, and they will kill dogs that are in territories they wish to claim.

But dog genes are getting into the wolf population at pretty high rate in Eurasia, a much higher rate than you would think of for two distinct species.

A lot of the people who have a hard time recognizing dogs as wolves are tired of bad dog training advice that is based upon bad wolf science.  They might also be tired of claims from the raw feeding community that say we must feed dogs like wolves.

But just because people misuse the classification does not infer that the classification is wrong.

Cladistically and genetically, dogs represent a now extinct population of Eurasian gray  wolves.  If these terms mean anything, then dogs are Canis lupus familiaris.

These theorists are always going to have a reason to say that dogs are not wolves, just like the BAND theorists.  Indeed, it may be necessary to refer to them as DANW (Dan-double u), for they are they are coming up with reasons to avoid classifying dogs as wolves, no matter how much genetic or archaeological evidence is presented.

In the grand scheme of things, classifying dogs has little effect on our practical understanding of them, but this continuous phylogeny denial makes the dog world seem oddly out of step.

No one would miss a beat if you called a Hereford a domesticated aurochs.  A pekin duck a domesticated mallard? No problem.

But if you say dogs are wolves, which they clearly are, then you’re anti-science.

I’m not, though. You’re the one rejecting cladistics for your special classification model.

I’m adhering to the same model that would be accepted with any domestic species and its wild ancestor.

You’re just rejecting it because you think that’s what the science says. Maybe, but it’s hard to argue with DNA.

But they do it on Maury Povich every day, so why not?

Update: A more recent study that examined the genomes of gray wolves from across their range revealed that 62 percent of all Eurasian wolves have some dog ancestry. That’s much higher than the genome comparison study mentioned above. 

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