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Archive for the ‘wolves’ Category

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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Lots of footage of Algonquin Park’s wolves, which are heavily admixed with coyotes, even breeding with them now when both populations are relatively stable. You can really see the coyote influence in this wolves, for these are the closest thing to a population of 50/50 “coywolves” in the wild.

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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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When I was a kid, Nature on PBS had a documentary about Simien jackals in the Ethiopian Highland. I remember being so fascinated by these jackals, particularly how they lived in extended family groups centered around a breeding pair. Even then, I marveled at how these animals had such a similar social structure to wolves, and my childish speculations made me wonder if these jackals could have told us how pack behavior in wolves first evolved.

But I grew up in an era before the internet, and I didn’t spend time looking at Simien jackals until I was in undergrad. I was at an old Borders bookstore, which don’t exist anymore, and I picked up a guide to African mammals. I perused my way to the canid section, hoping to find the section on bat-eared foxes. I had just read a book that documented the touching paternal behavior of this species, and I wanted to see if the guide mentioned this behavior. As I flipped through the pages, I came across the photo of the Simien jackal, but the caption under it said “Ethiopian wolf.”

I was somewhat confused by this new designation, so I read through entry on this new “wolf.”  The entry elucidated that some new DNA studies had found that the Simien jackal was found to be much more closely related to wolves than to other jackals in Africa, and the new name reflected this genetic discovery.

At the time, I was much more science illiterate than I am now, and I began to wonder if wolves had truly lived throughout Africa during the Pleistocene. Maybe these wolves were the source of the domestic dog, because we humans were a truly African species.

Later on, more studies came out.  Lots of papers suggested that some North African golden jackals were some kind of relict form of wolf in Africa, but most strongly suggested that there still were golden jackals in Africa. It was only 2015, that more in depth analysis of golden jackal, wolf, and coyote DNA revealed that all golden jackals in Africa were actually derived from a gray wolf-like ancestor. The current move it to call these animals African wolves or golden wolves, but a huge debate exists on what the exact scientific name should be: Canis lupus lupaster? Canis lupaster? Canis anthus?

I remain agnostic on what the exact scientific name for the golden wolf should be. I need more evidence, more data, before I’m going to latch  onto something. All of these problems are greatly complicated by the discovery that coyotes and gray wolves are much more closely related to each other than we thought, and the proposed million-year split between the two species was often used to gauge when the rest of the genus diverged.  These animals might all be much more closely related to each other than we imagined. 

But an even more surprising discovery just came out.  A recent genome comparison study revealed that hybridization was a major part of the evolution of wolf-like canids, but it also revealed that the golden wolf was itself a hybrid between Ethiopian wolf and the gray wolf. The authors did not estimate when this hybridization happened, but it clearly did.

This discovery points to this possible story about the Ethiopian wolf. Ethiopian wolves and gray wolves are not in any way sympatric. When the Ethiopian wolf was thought to be the only wolf in Africa, it was marveled at how a wolf managed to hold on in Africa, holding onto the last remaining cold parts of East Africa in the Ethiopian Highlands.

But if the golden wolf is really a hybrid between the gray wolf and the Ethiopian wolf, the Ethiopian wolf must have had a wider range. I bet it was even more generalist in its predation habits to have had such a wide range than the current rodent-filled diet of its surviving population. 

And then at some point, gray wolves began to wander down into Africa. These were probably primitive forms of the species, perhaps explaining why Himalayan wolves, a supposed basal form of gray wolf, share an x-chromosome with the golden wolf.

These gray wolves swamped the Ethiopian wolf range in North and East Africa, mating with the Ethiopian wolf.  This African gray wolf evolved to become smaller and more generalist, much like a jackal, but in the main, it retained a hybrid genome that is 72 percent gray wolf and 28 percent Ethiopian wolf.

For whatever reason, the gray wolf and the hybrid golden wolf never spread into the Ethiopian Highlands, where the Ethiopian wolf remained as relatively pure species.  These Ethiopian Highlands wolves had adapted to a rodent-rich diet in some of the harshest terrain in Africa, and there, they live on a relics from a time that has since passed.

They are like the last woolly mammoths of Wrangel and St. Paul Islands. The woolly mammoth of North America and Eurasia went extinct 10,000, but the ones on these two islands held on for much longer. The one on St. Paul went extinct 5,600 years ago, while the Wrangel Island population went extinct around 4,000 years ago. The St. Paul population went extinct as the lake on the island failed to provide them enough water, while the Wrangel population suffered a damaging blow when a deleterious mutation, which caused the mammoths to develop coats much like “satin” rabbits in which the coat grew shiny but less dense and useful for protection against the element, spread throughout the very inbred population.

By the time those mammoths went extinct, human civilizations were already well-advanced. We were already moving well into the agrarian epoch of Mesopotamia and Egypt, and we ceasing to be creatures of nature and becoming what we think we now are.

If the mammoths of Wrangel had never developed that deleterious mutation, we might be able to see them today, just as we can with the Ethiopian wolf.

Ethiopia today promotes the Ethiopian wolf as a major attraction in ecotourism. The country is doing all it can to preserve the species, and it very well be saved, so long as diseases from domestic dogs are held at bay and inbreeding issues don’t result the gene pool becoming swamped with a deleterious mutation or just general inbreeding depression.

No Ethiopian wolf will ever be on display at a Western zoo. You have to go to Ethiopia to see one. They hold onto this precious relic and treasure it as a vital natural resource and national treasure.

And that is how an endangered species should be treated. 

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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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dholes

We know that hybridization is a big thing in the genus Canis.  Indeed, scientists are still debating about the validity of certain species because some of the extant forms of wolf could very well be hybrids between gray wolves and closely related species. Everyone thinks that the large coyotes we see in the East are all coywolves, even though they don’t have that much wolf ancestry. but then we have very good genomic data that shows that coyotes and gray wolves really aren’t that different genetically.  We know that Ethiopian wolves were threatened with and still could be threatened with hybridization from domestic dogs, but we also know that getting dog genes into a wild canid isn’t always a bad thing. Wild gray wolves in North America got their black color variant from a single Pre-Columbian black dog that crossed into the population between 1,500 and 7,250 years ago in the Yukon or the Northwest Territories.

I have often wondered if we could detect hybridization that went on long before all these wolf-like canids truly diverged, and a recent paper in The Journal Cell reveals that hybridization has always been a feature of these wolf-like canids. Gopalakrishnan et al. compared the genomes of gray wolves, coyotes, domestic dogs, golden jackals, the African golden wolf, the Ethiopian wolf, the dhole, and the African wild dog to see if there was any evidence of hybridization in the lineages.

The authors found that the African golden wolf was actually a hybrid species that developed from gene flow between the gray wolf and the Ethiopian wolf, which likely had a much more extensive range in Africa than it does now.  The authors also found that the clade (which I think is actually a single species) that includes the dog, wolf, and coyote received genes from an unknown species of canid. The dhole and African wild dog have also hybridized in the past, probably because both the dhole and African wild dog once had ranges that overlapped in the Middle East or in North Africa.

The discovery of this unknown species is perhaps the most intriguing. The authors speculate that it might have been the dire wolf or the extinct North American dhole, but seeing that this species fairly close to the division between the dhole and African wild dog, I think a more likely candidate is Xenocyon lycaonoides.  This animal has been posited as an ancestor the dhole and the African wild dog, but a more convincing argument is that the African wild dog derived from Lycaon sekowei.  It is not clear yet what the dhole derives from, but it could have derived from Xenocyon or shared a common ancestor with it.

Xenocyon was the dominant wolf-like canid in Eurasia and Africa during the early part of the Pleistocene, but by the mid-Pleistocene, it began to become less common, and as its numbers dwindled, the diminutive wolf, Canis mosbachensis, began to fill its niche, eventually evolving into the modern gray wolf, which also led to the coyote and domestic dog lineages, as well as the hybrid African golden wolf.

Maybe, as the Xenocyon’s numbers dwindled, a few remaining ones hybridized with C. mosbachensis, perhaps introducing some genes from better pack cooperation and larger size that helped the smaller wolf fill the bigger canid’s niche.

The authors are clear that we need lots of ancient DNA from these extinct canids before we can engage in flights of speculative fancy, but seeing that this unknown canid was so close to the dhole, I think that this animal is a better place to look. Xenocyon might be a bit too old to find viable DNA in fossil remains, but it is certainly possible that we could find some.

So yes, hybridization has greatly affected the evolution of wolf-like canids in the modern era, but hybridization always has. Similar findings have been discovered in bears and various members of the cat family.  My guess is that virtually every clade will have had some of this going on, even if the current species do not hybridize.  Speciation happens, but chemical interfertility isn’t lost for quite some time after speciation. Gene flow continues on with related species, which continues to affect their evolution.

Yeah, evolution is a tangled bush that also has vines that reach out and grab adjacent and not so adjacent twigs.

 

 

 

 

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