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Posts Tagged ‘Canis lupus’

We spend a lot of time debating about how wolves became dogs. A huge debate exists in the archaeological and paleontological literature about how one can determine whether the remains of a canid represent a wolf, a dog, or a transitional form between wolves and dogs. This debate is why the oldest dog remains are dated to around 14,000 years ago and come from the Bonn-Oberkassel site. Anything older than that, a big debate exists among experts about what can be used to define a wolf, a dog, or a transitional form.

But this debate does not exist solely in relatively recent transition between wolves and dogs. The entire evolution of Canis lupus is a hotly contested and often contradictory, depending upon which source one reads and whether one is looking a source that relies upon paleontological and morphological analysis or one that looks at the molecular evolution of the species.

It is well-accepted in European paleontology that Canis lupus evolved from Canis mosbachensis. Mark Derr paid particular attention to this evolution in his How the Dog Became the Dog. He posits that the extinction of the large hunting dog, Xenocyon lycaonoides, created an ecological niche that could be filled by the Mosbach wolf evolving into the gray wolf.

Yes, the Mosbach wolf was smaller than the modern gray wolf. Individuals from Northwestern Europe were mostly about the size of a modern Indian wolf or a “red wolf.” Indeed, the similarities between some of these mosbachensis wolves and red wolves are the best evidence for a unique red wolf species, for one can argue that red wolves are just a relict form of the Mosbach wolf that held on in Eastern North America. Of course, the genetic data do not agree with this assertion, but it is an interesting idea nonetheless.

My reading is that the Mosbach wolf gave rise to Canis lupus in Eurasia between 300,000 and 500,000 years ago. The coyote, though often posited as a primitive Canis, is actually derived from a divergent form of Canis lupus that got marooned in the American Southwest some 50,000 years ago and evolved to fit a jackal-like niche on a continent already dominated by dire wolves.

The Mosbach wolf disappeared from the fossil record around 300,000 years ago, but there is always a debate as to the possibility that it held on longer. The red wolf and Indian wolf are certainly possibilities for its continued existence today, but as we’ve looked at more wolf genomes both of those don’t come out so distinctive. Every study that I’ve seen that uses Indian wolf genomes finds that they are divergent Canis lupus, and the red wolf is a cross between wolves that are of that coyote type and relict Southeastern gray wolves from a later invasion of the continent. I do think there is pretty good historical data that some smaller wolves that we would define as coyotes lived in the Eastern states at the time of contact, particularly the small brown wolf of Pennsylvania mentioned by Shoemaker and the small “wolues” of Jamestown mentioned by John Smith. My guess is that no one really took stock of what they were killing when they killed off the wolves of Eastern states. It is very possible that coyote-like wolves were killed off in great numbers along with the big ones, and later on, coyotes from the plains came East, crossing with wolves and even relict original Eastern coyotes to form the modern Eastern coyote. The red wolf and the larger Eastern coyote are thus recreations of the Mosbach wolf that have happened in modern times.

In Europe, one potential late surviving Mosbach wolf was thought to have been found in Apulia, Italy, at the Grotta Romanelli site. Wolf remains have been found in the cave that date to between 40,000 and 69,000 years ago and they were often described as belonging to a late surviving Mosbach wolf. A recent morphological analysis revealed that these remains were of a peculiar form of Canis lupus that lived in that part of Southern Italy, and they were not of any kind of Mosbach wolf.

However, the Mosbach wolf is particularly intriguing. Occasionally, it has been posited as a direct ancestor of the domestic dog, but because we don’t have an overlap between the signs of the earliest dog domestication and the existence of Canis mosbachensis in the fossil record, one should be very careful in making such an assertion.

This same caveat should be placed when one sees Canis variabilis posited as dog ancestor. For one thing, there is no such thing as Canis variabilis. Instead, all the specimens listed as this species that come from the Zhoukoudian site in China have now been reassigned to Canis mosbachensis. This reassignment posits them as Canis mosbachensis variabilis, so whenever one encounters that “Canis variabilis” in a paper, just remember that they are discussing a particular East Asian form of the Mosbach wolf.

From my own speculative meta-analysis, it seems that the Mosbach wolf is ancestral to the entire wolf/dog/coyote species complex, which may include the African golden wolf, and the Eurasian golden jackal. A genome comparison study that included dogs, wolves, and one Israeli Eurasian golden jackal found that the divergence between the golden jackal and the dog and wolf species happened just before the anatomically modern Canis lupus replaced Canis mosbachensis in the fossil record. The Eurasian golden jackal could potentially be derived from a diminutive form of Canis mosbachensis that moved toward a more generalist scavenger form.

We also have some evidence of small Mosbach wolves in Europe that could have potentially gone in the direction of the golden jackal. This specimen was found not far from the Grotta Romanelli wolf that were found to be anatomically modern and not Mosbach wolves. It was found at the Contrada Monticelli site in Apulia. It was unusual in that it was quite a bit smaller than the Mosbach wolves found in other parts of Europe, and the authors found that Mosbach wolves were as morphologically variable as modern wolves are.

In North Africa, we also have a recent discovery of a canid that was much like the Mosbach wolf. The authors thought it was a bit different from the Eurasian form, and they decided to call this species Canis othmanii. This African wolf-like canid was found at a site in Tunisia and dates to the Middle Pleistocene, and it could potentially be the basal gray wolf that hybridized with the Ethiopian wolf to make the African golden wolf. More work needs to be done on this specimen, for it very well could wind up like Canis variabilis, a regionally distinct form of the Mosbach wolf.

The really fuzzy part about Canis mosbachensis isn’t that it is the ancestor of the gray wolf. The educated speculations I make about its relationship to the golden jackal and the golden wolf could be debated, and we need lots more data to figure out if I am right or not.

The really fuzzy part is what came before the Mosbach wolf. Most scholars think that Etruscan wolf (Canis etruscus), which makes an appearance in the fossil record around 2 million years ago, is the ancestor of the Mosbach wolf. For years, there was a debate about whether the Mosbach wolf was a chrono-subspecies of the Etruscan wolf or a chrono-subspecies of the gray wolf. All these suggestions would be technically true, simply because we could regard the Etruscan wolf-Mosbach wolf-gray wolf as a species that lasted and evolved over this time period.

However, a bit of a debate now exists as to whether the Etruscan wolf is the ancestor of the Mosbach wolf. An extensive morphological analysis of Etruscan wolf remains and those of another Canis species called Canis arnensis, which compared both to the modern black-backed jackal, the gray wolf, the golden jackal, and the golden wolf, found that our previous delineation between arnensis as being jackal-like and etruscus as being wolf-like were over-simplifications. Some characters of arnensis are much more like modern gray wolves than etruscus is, and it is possible that arnesis gave rise to the Mosbach wolf. Still, the bulk of scholarship thinks that the Etruscan wolf is the ancestor of the Mosbach wolf.

However, because the Mosbach wolf was not included in the analysis, it might be difficult to make such a conclusion. However, maybe the Etruscan wolf or something like it is the ancestor of the Ethiopian wolf. The ancestral Ethiopian wolf must have had an extensive range in Northern Africa for it to have hybridized with Canis mosbachensis, Canis othmanii, or a basal modern gray wolf to form the African golden wolf.

I have focused most of this post on the origins of gray wolves in the Old World, but the first Canis species to evolve were found in North America. Canis lepophagus first appeared in the fossil record 5 million years ago. It was very similar to a coyote or a Canis arnensis of the Old World. This is the part of the story where the molecular data has largely shaken up what we used to believe about coyotes. Lepophagus is thought to have evolved into the larger Edward’s wolf (Canis edwardii), which is sometimes called Canis priscolatrans. These animals might have been the same species or very closely related to the Etruscan wolf. The modern coyote is thought to have derived from edwardii/priscolatrans/estrucus 1 million years ago, but genome-wide comparisons put the existence of most recent common ancestor of gray wolves and coyotes at less than 51,000 years ago.

The dire wolf derived from Armbruster’s wolf (Canis armbrusteri). Armbruster’s wolf derived from Canis edwardii/priscolatrans/etruscus 1.8 million years ago. The dire wolf then evolved from that species 125,000 years ago, which means the dire wolf’s most recent common ancestor with modern wolves and the coyote may have been as far back as 2 or even 3 million years ago.

This analysis is still being worked out. The molecular data is constantly throwing wrenches into the machinery of paleontology, especially the paleontology of canids. The most successful extant canid lineage are full of parallel evolution and phenotypic plasticity, and in this way, it has become quite a challenge to sort out the evolutionary history of these species. At various times, large wolf-like forms have evolved as have smaller coyote or jackal-like forms.

The story of Canis starts with a coyote-like lepophagus, but right now, its likely niche is adopted by the modern coyote, which also very similar to it. But the molecular data suggest that the coyote evolved to adopt this similar niche from a larger Eurasian gray wolf and that it did not directly descend from lepophagus over 5 million years in only North America. Instead, it evolved into wolves that wandered into Eurasia, becoming the Mosbach wolf and then anatomically modern gray wolf. Some of these wolves wandered back into North America and became generalist scavengers in the land of the dire wolf.

Very similar stories likely are lost to us, but we must understand that the history of wolves is not just about getting bigger and developing pack-hunting behavior. That is one part of the story, but another part is about evolving to fit niches, which sometimes means evolving a smaller size and more generalist diet.

Some of my ideas here are very speculative, but I think they are nested in my reading of the available literature. Do not assume that I have the final story of how these creatures evolved, but just understand that the molecular side is so rarely considered in paleontology literature that it is almost like we’re reading evolutionary history of two different lineages.

More work must be done to formulate a synthesis between these two disciplines. Otherwise, there will be continued conflict, and the one using an older methodology and often working with much more incomplete data-set will fall by the wayside. And that is not the one using full genomes.

If we know what problems exist using morphological studies on extant and recently extinct canids, it is very likely that we’re missing important data on many extinct species, one for which there is no DNA to test.

Still, paleontology has much to tell us about the way early wolves lived. It can tell us much about how the ecosystems were and why wolves evolved in the way they did. But its methodologies often miss relationships between extant forms and miss the tendency toward parallel evolution.

I tried for about two years to watch Joe Rogan’s interview with Dan Flores, who wrote a book on coyotes that I think is quite full of misunderstandings about canid taxonomy. When Rogan questioned him about the papers that show a recent origin for the red wolf, Flores pretty much just dismissed those papers because they didn’t look at fossil.

That’s not how it works. Within canids, we know that parallel evolution is a big thing, and it is very possible that coyote-like and red wolf-like canids have evolved more than once on this continent. Indeed, a careful reading of the paleontology and molecular data strongly suggests that this is the case.

In fact, it has always been the case with these wolf-like canids. Big ones evolved from small ones, but sometimes, the big ones become small, because it is a better fit for survival.

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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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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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African golden wolf

What we do know about the origins of Canis species is much more hotly-contested than what we know about the evolution of our own species. The earliest fossils of the genus are roughly 6 million years old, and the oldest species in the “wolf lineage” is Canis lepophagus, which lived in the American Southwest and Northern Mexico 5 million years ago.  This species is often posited as the direct ancestor of the coyote, and it may have been a direct ancestor of all the entire wolf-like canid lineage.

Of course, recent discoveries that have come from full genome comparisons make things a little complicated. With the discovery that coyotes diverged from gray wolves as recently as 50,000 years ago, the linear evolution from Canis lepophagus to Canis latrans is probably invalid.  Further another full genome study that used a single Israeli golden jackal (Canis aureus) as the outgrouping sample to determine when dogs and gray wolves split, revealed that this particular jackal diverged from gray wolves less than 400,000 years ago.

Both of these dates are far more recent that the millions of years that are assumed to separate these wolf-like canids from each other. Of course, more work must be done. We need more studies on coyote genomes, but these researchers have come across what could be the most important discovery in our understanding of the evolution of Canis species. Depending upon the study, coyotes and gray wolves were thought to have diverged between 700,000 to 1 million years ago, and this assumption is used to calculate when other Canis have diverged.

Now, this assumption always did bother me, because if Canis lepophagus leads directly to Canis latrans, where do wolves fit in?  Because in order for that model to work, gray wolves have to evolve from a very small coyote-like ancestor with very few transitions in between. It always just seemed to me like it was unworkable.

Further, there is a whole host of literature on the evolution of gray wolves in Eurasia, and in most European literature, there is a general acceptance of how gray wolves evolved from a smaller wolf called Canis mosbachensis.

Wolfgang Soergel, a German paleontologist at the University of Tübingen, discovered Canis mosbachensis at a site near Jockgrim in 1925. The animal is sometimes called the “Mosbach wolf,” which means it was found in the Mosbach Sands, where many fossils from the Middle Pleistocene have been found.

Mark Derr was particularly interested in this species in his How the Dog Became the Dog.  He points out that the earliest dated fossils of this species are 1.5 million years old and come from the ‘Ubeidiya excavations in Israel.  The most recent Canis mosbachensis remains in Europe are about 400,000 years old, after which time they were replaced by Canis lupus.  Derr speculated about the relationship mosbachensis might have had with early hominin species, which were also well-known from that site, and suggested that they might had some kind of relationship.

Further, there is a growing tendency among paleontologists to group Canis mosbachensis with another wolf that was its contemporary. This wolf, called Canis variabilis, was discovered at the Zhoukoudian Cave System in China in 1934. Its discoverer was Pei Wenzhong, who became respected paleontologist, archaeologist, and anthropologist in the People’s Republic of China. It was a small wolf with a proportionally smaller brain, and it has long been a subject of great speculation.

And this speculation tends to get lots of attention, for this cave system is much more famous for the discovery of a type of Homo erectus called “Peking Man.”  It is particularly popular among the people who insist that dogs are not wolves, which is about as scientifically untenable as the “birds are not dinosaurs” (BAND) clique of scholarship.

Mark Derr and as well as more established scholarship have begun to group variabilis and mosbachensis together. Variablis has also been found in Yakutia, and it may have been that varibablis nothing more than an East Asian variant of mosbachensis.

These wolves were not large animals. They varied from the size of an Eastern coyote to the size of an Indian wolf. They were not the top dogs of the Eurasian predator guild.

Indeed, they played second fiddle to a larger pack-hunting canid called Xenocyon lycaonoides, a large species that is sometimes considered ancestral to the African wild dog and the dhole, but the recent discovery of Lycaon sekoweiwhich was a much more likely ancestor of the African wild dog, suggests that it was more likely a sister species to that lineage.

Although canids resembling Canis lupus have been found in Alaska and Siberia that date to 800,000 years ago, anatomically modern wolves are not confirmed in the Eurasian faunal guild until 300,000-500,000 years before present.

I’m throwing a lot of dates at you right now, because if the modern Canis lupus species is as recent as the current scholarship suggests, then we can sort of begin to piece together how the entire genus evolved.

And we’re helped by the fact that we have an ancient DNA study on a Yakutian “Canis variablis” specimen. This specimen would have been among the latest of its species, for it has been dated to 360,000 years before present. Parts of its ancient mitochondrial DNA has been compared to other sequences from ancient wolves, and it has indeed confirmed that this animal is related to the lineage that leads to wolves and domestic dogs.  The paper detailing its findings suggests that there is a direct linkage between this specimen and modern dog lineages, but one must be careful in interpreting too much from limited mitochondrial DNA studies.

360,000 years ago is not that far from the proposed divergence between gray wolves and the Israel golden jackal in genome comparison study I mentioned at the beginning of the post.

This really could suggest something a bit controversial and bold. It make take some time for all this to be tested, but it is a hypothesis worth considering.

I suggest that all this evidence shows that Canis mosbachensis is the ancestor of all interfertile Canis, with the possible exception of the Ethiopian wolf.

If the Ethiopian wolf is not descended from that species, then it is a sister taxon. It is not really clear how divergent Ethiopian wolves are from the rest of interfertile Canis, but their divergence estimates currently suggest that it diverged from the rest of the wolf-like clade 1.6 million years ago, which is just before Canis mosbachensis appears in the fossil record.

If that more recent date holds for the split for the Eurasian golden jackal, then it is almost certain that this hypothesis is correct.  The Eurasian golden jackal may be nothing more than a sister species to a great species complex that includes the coyote, gray wolf, dingo, and domestic dog that both derived from divergent populations of Canis mosbachensis. 

The exact position of the Himalayan wolf and the African golden wolf are still not clear. We do know, though, that both are more closely related to the coyote and gray wolf than the Eurasian golden jackal is, and if its split from the gray wolf is a recent as less than 400,000 years ago, then it is very likely that all of these animals are more closely related to the main Holarctic population of gray wolves than we have assumed.

The recent divergence of all these Canis species is why there is so much interfertility among them.

And if these animals are as recently divergent as is inferred, their exact species status is going to be questioned.

And really should be, at least from a simple cladistics perspective.

More work does need to be done, but I don’t think my hypothesis is too radical.

It just seems that this is a possibility that could explored.

 

 

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Many people don’t like that I consider dogs to be the same species as wolves.

And usually what they’ll do is accuse me of holding views I don’t have.

For example, I don’t say that the average person should keep a pet wolf. The chances of that going wrong are just too high, but it doesn’t mean that it will never work out.  I have to point to several cases of people keeping wolves and having no problems with them, most notably Wags, the tame wolf that Adolph Murie kept while studying the wolves of Denali. Wags was taken from the den of a wild pack, and she wound up becoming something like a golden retriever in wolf form. Wolves have also been trained as hunting dogs and working dogs, and at least one turned out to be a decent bird dog and retriever.

However, the chances of a human-wolf relationship going wrong are very high, so I do not recommend that people keep pet wolves without learning as a much as they can– and of course, getting the proper licenses.

The other attack I get is that I think dogs are wolves, and therefore, I must believe that we should use compulsory, alpha-based training regimes.

That’s a position I not only don’t have, it is a position I have denounced as utterly unscientific and untenable in the modern era. (See Mark Derr’s piece in the New York Times for a good explanation of why).

Now those first two are pretty easily dealt with, but a third one requires a bit more of an explanation.

This third argument requires a bit sophistication to fully understand, but it’s one that I think can be explained if we look at other cases in nature for comparison.

This argument is one that is made by Raymond Coppinger in his book on dog domestication and behavior. There is a chapter in the book in which he denounces any attempt to represent dog phylogeny in their scientific name, which is Canis lupus familiaris. Coppinger totally defends the old scientific name Canis familiaris because dogs and wolves occupy different ecological nichees.

It’s definitely true that lap dogs have a very different ecological niche than large moose- and bison-hunting wolves in Canada.

However, what about Middle Eastern pariah dogs and Arabian wolves?  Both animals scavenge for most of their food. Neither forms large packs based upon a mated pair, but they essentially  have the same ecological niche. And they do exchange genes quite a bit, although because the wolves are far less common, this gene exchange is much more limited than it might have been.

The same goes for the wolves and stray dogs of Italy. These dogs and wolves don’t hunt prey, because there aren’t many prey species about. Instead, they hang out at garbage dumps and live on that. The wolves of Italy are much more interbred with dogs than people realize. Dog genes for black coats and dewclaws on the hindlegs are working their way into the wolf population.

If we actually take Coppinger’s argument out to its logical end, then wolves themselves represent several species, even though genetically they comprise just a single species. Wolves in the high arctic hunt muskoxen, while wolves in the Middle East hunt gazelles and hares and mainly scavenge. The newly discovered African wolf subspecies (Canis lupus lupaster) isn’t even the top predator in its ecosystem, and it subsists largely by scavenging kills and hunting small prey.

Yet they are all classified as wolves (Canis lupus).

If wolves can occupy such a wide variety of ecological niches and still be considered the same species, why on earth would we not broaden it out and allow dogs to be classified as wolves?

Just as Arabian wolves are adapted to living in the deserts and arctic wolves have adapted to living in polar regions, domestic dogs are wolves that have adapted to live with humans.

I don’t know why this is so hard to accept, but there is a lot of resistance in some quarters to considering dogs a subspecies of wolf.

But that’s exactly what they are.

Now, in other species, there are different subspecies that have different ecological niches, but no one contends that they should be separated into distinct species on the basis of their differing niches.

Let me give you one that is pretty close to home.

To me, this is a fox squirrel (Sciurus niger).

Eastern or northern fox squirrel (Sciurus niger vulpinus).

It’s a big squirrel with thick tawny gold tail and belly.  They live on the border of pastures and hardwood forests, and they are more common along river valleys in West Virginia than ridgetops. Densely forested ridges tend to have mostly Eastern gray squirrels, which are smaller and usually have gray tails with white banding. In my area, these are the two most common squirrels, although one sometimes see American red squirrels (“fairydiddles.”)  The fox squirrel is the largest tree squirrel in North America, and it is from this subspecies that they get their common name. Their tales actually look like those of a red fox, and their full scientific name reflects this similarity– Sciurus niger vulpinus. This subspecies is found from the interior Mid-Atlantic states and the Appalachians north and west to the prairie provinces.

However, this is also a fox squirrel:

Southern fox squirrel (Sciurus niger niger).

This is the Southern fox squirrel, and it is the subspecies one will find in Eastern North Carolina and most of South Carolina.

They superficially look nothing like the fox squirrels I know so well, but they are considered the same species.

However, the two subspecies are quite different from each other.

The vulpinus subspecies is quite adaptable. They have been introduced to California, where they have thrived, and if you can live from Applachia to Saskatchewan, you can do pretty well no matter what the conditions are.

The niger subspecies is in decline. They are almost entirely dependent upon the long-leaf pine forests that once covered much of the Southeast. For those of you who have not been in this part of the South, most of the land is dominated by subtropical pine forests. Historically, the long-leaf pine has been the dominant pine, but these old growth long-leaf pine forests have been cut– and the land was replanted with more commercially lucrative short-leafed and loblolly pines.  The fox squirrels prefer the more open understories that the long-leaf pines provide, and the short-leaf and loblolly forests are much better suited for Eastern gray squirrels.

In states that have both vulpinus and niger fox squirels, the vulpinus subspecies prefers to live in any available oak-hickory forests, while the niger subspecies prefers to live where there are stands of subtropical pine– especially if it’s long-leaf.  In some parts of the Piedmont, these two different kinds of forest can be relatively close to each other, but as far as I know, no transitional zones between vulpinus and niger fox squirrels have been documented. They probably do exchange genes where their ranges overlap, but because niger fox squirrels are so habitat specific, there likely isn’t much of one.

No one consideres vulpinus fox squirrels a separate species from niger fox squirrels, even though they have very different ecological niches. The niger subspecies is also quite a bit larger than the vulpinus subspecies, which is in conflict with Bergmann’s rule. In other normal situations, taxonomists would at least try to consider them to be different species.

In fact, they have a better claim to having a separate species status than dogs and wolves, but I don’t think anyone would seriously consider these fox squirrels to be different species.

After all, there are several different subspecies of fox squirrel besides these two.  The most famous is the critically endangered Delmarva fox squirrel (Sciurus niger cinereus), which looks like a giant Eastern gray squirrel, which even more habitat specific than the Southern fox squirrel. They also are specialized to living in the Mid-Atlantic pine forests from Southern New Jersey to the Virginia’s Eastern Shore. It currently is found only in Eastern Shore portions of Virginia and Maryland.

Vulpinus fox squirrels are much more habitat generalists than either the Southern or Delmarva fox squirrels. They have a different ecological niche, and if one really wants to play around with Coppinger’s adamant defense of Canis familiaris, then we have to split up the fox squirrel species.

Ecological niche can be used to determine species status, but to rely upon it alone, as Coppinger does in his defense of the usage of Canis familiaris, is to inadvertently open up whole taxons to splits that are pretty hard to justify on face value.

So if one isn’t willing to say that there are multiple species of fox squirrel, we are going to have go with Canis lupus familiaris.

Sorry, folks. Dogs are wolves.  The arguments on the contrary make no sense in the light of what we know about other species.

Update: It turns out that all these subspecies of fox squirrel have only diverged in the past 14,000 years.

 

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Woolpy and Ginsburg (1967) were able to tame adult wolves. These wolves became fully social to all people and would greet everyone with a gentle face bite, which may be an inherited greeting motor pattern in northern wolves.

It is often said that adult wolves cannot be tamed. The animals are just too emotionally reactive and fearful to ever accept human contact, so if a facility wants to have wolves that can be handled, it must take them from their mothers at an early age, usually said to be before they are three weeks old.

However, there have been those who have tamed adult wolves. The most notable attempts were done by Jerome Woolpy and Benson Ginsburg of the University of Chicago.  Their success in taming adult wolves was described in The American Zoologist in 1967, but it is still often said that adult wolves that have not been socialized to people as puppies are impossible to tame.

The issue is not that it is impossible.   The issue is that it requires some special housing equipment and lots of time and patience to do so.

It should be noted that even though Woolpy and Ginsburg were able to tame these adult wolves, it does not automatically follow that they became exactly like domestic dogs. Although these wolves became very friendly toward all people, it is unlikely that these wolves could be used to do much of the specialized work that we ask of domestic. However, it is inaccurate  to claim that it is impossible to tame an adult wolf.

Woolpy and Ginsburg based their 1967 paper on their experiences with seven wolves. Three were socialized as neonatal whelps and were in constant contact with people throughout their lives.  Three were socialized as young puppies and adolescents and then turned out with other wolves that had not been socialized, and one was an adult wolf that had received no human contact until it was five years old. All were able to become socialized to people, and those that were socialized as adults were friendly toward all people. However, those three that were socialized as puppies and then turned out with other wild wolves were not social toward people at all. These wolves had to be tamed in the same way as the five-year-old.

The authors describe their socialization of adult wolves as follows:

So adult wolves can be tamed. It just requires a lot of time and expertise (and a bit of courage).

Granted, this was a very low n study, and three of the wolves that were tamed as adults had initially been imprinted on people as very young puppy.

But one was tamed as a “middle-aged” adult that had no prior experience with people.

So it can be done.

I believe the researchers were able to repeat these results with other wolves, for these researchers worked extensively with captive wolf colonies.

Other researchers haven’t had so much luck.

And I think there is a very good reason for it.

At the time, it was assumed that the only way one could handle wolves was to be very rough with them. In much of the captive wolf husbandry literature, it discusses how important one must establish dominance over the wolves to deal with them. Some wolf experts and pseudo wolf experts like to use lots of physical force  and dominance displays in dealing with their charges. And those actions are just the ones used with the socialized wolves.

The unsocialized wolves are often netted and gripped with catch poles to vaccinate them and to tranquilize them for physical exams or transport to new facilities.

The use of these differing but harsher techniques on both socialized and unsocialized wolves doesn’t really endear the wolf to its care-takers.

If you read what Woolpy and Ginsburg actually did, there was none of this “I am the alpha wolf” mentality.  There was also no assumption that an adult wolf couldn’t learn to accept people as social partners.

They simply asked the wolf to be friends.

Of course, it took a while to ask the wolf the question.

But once the wolf understood what was being asked, it answered in the affirmative.

***

Now, I should warn that it is not a good idea for amateurs to catch wild wolves and coyotes and try these techniques.

Not only is ownership of these wild canids illegal in many states and municipalities, it is really not wise for amateurs who have very little experience to try to pet wild animals of any sort.

***

It should also be noted that all of these wolves were large hunting wolves from northern North America, and all had come from wild populations that had been historically persecuted.

All of these wolves had very strong fear reactions, which is one reason why the socialized wolf pups lost their friendliness to people when they were house with unsocialized wolves for an extended period of time.

It is unlikely that the ancestral wolves had such strong fear reactions, and therefore, it would have been easier for ancient hunter-gatherers to form relationships with them. Most wild dogs that are not heavily hunted are very curious about people, and it is likely that ancient wolves were much more likely to approach people out of curiosity than modern wolves are.

These wolves could have been socialized as adults. It should not be assumed, as some often do, that the original wolves that were domesticated were neonatal puppies. Adult wolves could have been tamed, even without the specialized techniques that Woolpy and Ginsburg used.

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From The Seattle Times:

Wildlife officials say the Northern Rockies gray wolf population has decreased for the first time since the animal was reintroduced to the region 15 years ago.

A census of the endangered species released Friday by the U.S. Fish and Wildlife Service showed the number of wolves fell by about 5 percent in 2010, to 1,651 animals.

Fewer wolves in Idaho accounted for the entire drop, as wolf numbers were up slightly in Montana, Wyoming, Oregon and Washington.

The decline is set against a backdrop of rising political pressure to allow more hunting of the predators, which have aggravated ranchers and sportsmen with attacks on livestock and big game herds.

The number of attacks on cattle was virtually unchanged. Sheep losses dropped sharply from 721 in 2009 to 245 last year.

Idaho is the reason for the population drop?

Well, Idaho does have a very active anti-wolf community, led by a Dale Gribble type named Ron Gillett:

Source.

 

 

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