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Posts Tagged ‘dire wolf’

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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dire wolf skeleton

I am not big on popular culture these days. I have not watched one second of Game of Thrones, but I do know that dire wolves have something to do with that series.  I am not into that genre of television. Give me an actual documentary about dire wolves, and I’ll be happy.

But I know that dire wolves are thing from that series only because I do sometimes get asked about them. I don’t know how they are portrayed in that series, but most people think of them as just super large gray wolves that went extinct at the end of the Pleistocene.

The funny thing is that there actually was a super large gray wolf that specialized in hunting large game that also went extinct at the end of the Pleistocene. This animal has been called the Beringian wolf, and although no one has dared to give it a subspecies status, it was essentially a form of gray wolf that hunted megafauna in much the same way that the dire wolf did. The two species were contemporaries, but the Beringian gray wolf did not live in the same parts of North America as the dire wolf, which was found through most of the Lower 48 of the United States and ranged down into northern South America.  This Beringian wolf apparently ranged from Alaska to Wyoming, while the dire wolf was found in mid-latitude North America and ranged south from there.

No one really pays that much attention the Beringian wolf, but it is very likely that everything we know about modern wolves would have applied to that animal. The only difference would be that this wolf was much more specialized in hunting large prey such as bison than modern big-game hunting wolves are.

The same cannot be said for dire wolves.  Dire wolves evolved solely in North America. The general consensus is that it evolved from Armbruster’s wolf, but the exact origin of Armbruster’s wolf is a bit of debate. One well-known hypothesis is that the common ancestor of the modern gray wolf and the Armbruster’s wolf-dire wolf lineage is Canis chihliensis, a Pliocene wolf-like canid. This is the hypothesis suggested by Tedford and Wang, who are leading authorities on North American canid evolution.

However, there is a whole host literature in Eurasian wolves that posits Canis mosbachsensis as the ancestor the modern wolf. This literature, I think, is a bit more robust, for the large numbers of samples of both archaic Canis lupus and Canis mosbachensis show how the wolves of Eurasia went from being small and gracile to larger and more robust over time.

It is possible that this Armbruster’s wolf/dire wolf lineage evolved from an entirely different grouping of the wolf-like canids. It also would place the common ancestor of the dire wolf and modern Canis lupus back millions of years, even to the point where dire wolves were at least as genetically divergent from modern wolves as modern wolves are from African wild dogs.

If that is true, then we cannot make many wild assumptions about dire wolf behavior by comparing them to modern wolves at.  We don’t have any preserved dire wolves in permafrost. They never lived where there are currently big stands of permafrost, so we will never have dire wolf pelts.

Attempts have been made to get DNA from the many Rancho La Brea tarpit dire wolf remains, but they have not been successful. It was found that it was just too difficult to separate the bone from the tar.

So we really don’t know exactly how closely related dire wolves are to modern wolves, but I would be surprised if they turned out to be as closely related to modern wolves as modern wolves are to coyotes.

Indeed, the real problem with all of this is much of Canis taxonomy and systematics is not entirely resolved. The real issue I have now is we have good genome comparison literature that shows a much closer relationship between wolves and coyotes than we previously believed. Much of our understanding of Canis evolution is that we have tended to think of a linear evolution from jackal-like forms to wolf-like form, when the truth of the matter is we have had jackal and wolf-like forms evolve independently of each other within different lineages of the wolf-like canids.

So we are taken aback with the findings that the two endemic African jackals, the black-backed and side-striped jackal, are the two most basal and divergent forms of the wolf-like canid clade, and we are even more taken aback that the dhole and African wild dog are not as distinct from the rest of the clade as these two African jackals. This finding has led to the rise of the genus Lupullela for these two jackals.

In addition, the creatures formerly known as African golden jackals were revealed to be much closer to wolves and coyotes than to the Eurasian golden jackal, which has led to a bit of a taxonomy war on what exactly to call these creatures, though the popular press likes to use the term “African golden wolf,” which was the name suggested in one of the papers documenting their discovery.

None of these discoveries would have been indicated through morphological analysis alone. One would think that black-backed jackals and coyotes were particularly close relatives, for they look and behave pretty similarly to each other. At one time, we would have classified both as primitive or basal Canis.  Today, I think the best description is that the black-backed jackal is a basal Canis, but that the coyote is actually a very derived but diminutive one.

So we have these problems with extant Canis species, and it is very likely that we’re missing the full picture on how dire wolves relate and compare to modern ones.

One thing that should be noted is that dire wolves had very odd bacula.  The baculum is the penis bone that exists in all but a few mammals, and you, if you are a male human being, are among these few mammals without one.

Dire wolves had longer bacula than gray wolves of the same size and they were kinked upward at an odd angle. This bone is probably indicative of a larger penis in a dire wolf than the modern one, and it also might give us some interesting clues about how dire wolves might have behaved.

I have suggested that having this male anatomy might have meant that dire wolves had more competition with sperm penetration than actual male on male conflict during the mating season. We know that within primates, those species that are better endowed tend to be less aggressive with other males of the same species. Those with smaller genitals tend to be more aggressive, and the reason posited for this difference is those with larger genitalia have given up on intermale aggression and the real competition is how far and how much sperm the male can produce.

Maybe something like this was going on with dire wolves. Maybe mating season with dire wolves was just a big ol’ wolf orgy, and the male that could penetrate the female deepest and with the most sperm wound up siring the offspring.

Even calling Canis dirus a “wolf” may not be accurate at all. If it truly is a more distant relative to the gray wolf than we currently assume, then we really need to be careful what we assumptions we are making.

A few years ago, there was a bit of fun speculation on the internet that the dire wolf was actually of South American wild dog clade. A few scholars had toyed with the idea, because there was these two odd species wolfish like canids that were known from the fossil record in South America, called Canis nehringi and Canis gezi. The former was always thought of as being very similar to the dire wolf, and the latter appeared to be somewhat similar to both.

This speculation led to this wonderful image, a depiction of the dire wolf as being an overgrown bush dog.  (The one on the right speculates a South American origin, while the one on the left just turns it into a wolf).

dire wolf bush dog

Of course, serious scholarship performed a phylogenetic analysis of these canids and revealed that Canis nehringi was actually a dire wolf offshoot. Canis gezi was found to be a South American clade wild dog.

So yes, this was a fun bit of speculation, but it’s not much more absurd than assuming that the dire wolf was that fundamentally similar to the modern gray wolf.

We just don’t know. I’m sure that we’ll get a good ancient DNA sample from a dire wolf soon, and we’ll be able to answer some of these questions.

But right now, we need to be very careful in assuming that the dire wolf was just an odd Pleistocene gray wolf.

We’re missing a lot of information, and a lot of the research on dire wolves was performed before we had all these “molecular surprises” with extant Canis species.

There is just so much we don’t know, and it might be a good idea to be careful about making assumptions about dire wolves by comparing them to their supposed modern equivalents.

Those equivalents might not be any more equivalent than those equivalents are to modern African wild dogs and dholes. Yes, there are some similarities, but African wild dogs and dholes are very different from wolves in terms of the exact dynamics of their pack behavior and hunting styles.

So we’re assuming a lot now about dire wolves, but it’s best to wait for me evidence before we play around with speculation. Hollywood will never take this cue, but maybe we should hold back a bit.

We just don’t know.

 

 

 

 

 

 

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dire wolf mesomelas

It was always assumed that the dire wolf and its kin, the endemic extinct North American wolves, were very closely related to modern wolves.

However, the genome of the dire wolf was just sequenced by a team of independent researchers at the Russian Institute of Cytology in Saint Petersburg.  The team of geneticists and paleontologists was led by Boris Yudin. The team wanted to have access to the remains of dire wolves at Rancho La Brea, but they were instead able to obtain access to several skeletons that were being held at the Indiana Museum of Natural History.

“It was very hard to get access to the specimens,” says Yudin,  who has always been fascinated by Pleistocene North American megafauna, “But once we did get access, the DNA sequences were quite easily obtained from the shoulder bones.”

“We were able to get one full genome sequenced, and then we began to compare this genome with other species in the genus Canis,”  says Yudin, “and using a Bayesian analysis, we were quite shocked to learn that the dire wolf wasn’t really a wolf at all.”

Most paleontologists had believed that the dire wolf was a sister species to the modern gray wolf, and if this assumption were true,  the dire wolf genome would be most similar to this species.

However, the dire wolf didn’t share an affinity with the gray wolf. Instead, it shared a much stronger relationship with the black-backed jackal, a species of canid found in East and Southern Africa, which is quite genetically distant from other wolves and jackals.

“There is even a debate as to whether the black-backed jackal even properly belongs in Canis,” says Yudin, “It is so genetically divergent.  But our research found that the dire wolf and the black-backed jackal are sister tax.”

Using the genetic differences between the dire wolf and the black-backed jackal to calculate when they last shared a common ancestor,  Yudin’s team estimated that the two species split only about a million years ago. Black-backed jackals and their current living closest relative, the side-striped jackal, are believed to have diverged from the rest of Canis some 5 million years ago, and the same is true of the dire wolf.

“The two divergent African jackals and the dire wolf form a clade, and if we are to classify the  two jackals outside of Canis, then the same will have to be done with the dire wolf,” Yudin points out.

“Within the dog family, the tendency towards parallel and convergent evolution cannot be underestimated.  We now know there are jackals and wolves that exist now and have existed that come out of divergent lineages. This is the most important discovery,” says Yudin.

So now we have the golden wolf of Africa, which is a convergent form of jackal out of the wolf lineage, and we have the extinct dire wolf, which was a divergent jackal that evolved into a wolf.

Yudin’s team plans on extracting the genome of the Armbruster’s wolf, which is conventionally believed to have been the direct ancestor of the dire wolf.  If this is true, then the Armbruster’s wolf will also share an affinity with the black-backed jackal.  The team also is beginning an analysis of Pleistocene coyote genomes from across the United States.

“It is an amazing time, ” says Yudin. “Many discoveries to be made.”

Disclaimer:  Please do not post this story as authoritative until reading this post that acts as a follow-up. 

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dire-wolf-baculum

Dire wolves are one of those creatures from the past that has captured the public imagination. They are conventionally dreamed of as being massive wolves, and Hollywood has created fictional ones the size of horses.

The truth of the matter is they were only slightly larger than the largest of modern North American wolves.

We know that they were closely related to modern wolves, but their exact position in the wolf family tree is still a bit contested.  The two species are close enough in appearance that it often takes a specialist to figure out whether one is looking at the skeletal remains dire or modern wolf the measurement of the skull features and limb proportions.

One feature, though, that is diagnostic of the dire wolf is its  robust and “perky” baculum.

If you don’t know what a baculum is, that’s because you’re human. In virtually ever other species, the males have a “penis bone” or os penis.  Where I grew up in West Virginia, it was not unusual for men to wear a raccoon’s baculum as talisman of both one’s virility and redneck bona fides.

The dire wolf is one of those ancient animals for which we have a lot of skeletal remains to examine.  In the famous La Brea Tar Pits, where the remains of over a million Pleistocene creatures have been found, dire wolves are the most common species to have been recovered.

The tar pits were a death trap for all sort of large herbivorous mammals, and when they became stuck in the natural asphalt tar, they were easy pickings for scavengers.  Dire wolves came to the tar pits to eat, but many, many of them died. Over 200,000 of them have been taken out of the site.

With such a big sample of dire wolf skeletal remains, paleontologists have been able to figure out quite a bit about their growth patterns, but of particular interest are the bacula of the male dire wolves.  They are shaped not the bacula of any extant canid. They are curved and robust, and when compared to modern wolves of the roughly the same size, they are 44 percent longer.

That is a unusual find, and it suggests something about dire wolf behavior that isn’t true of modern wolves.

Modern wolves generally reproduce through a mated pair. In most wolf packs living in most situations in the wild, only a single pair in a pack gets to mate and produce pups. Other wolves in the pack might mate, but their pups will either be killed or abandoned.

This doesn’t happen every time. If there is abundant prey, these young females are sometimes allowed to raise their pups alongside their mother’s litter.

But in most cases, they don’t get to raise pups.

Modern wolves spend a lot of energy making sure that the mated pair, who are usually parents of the other wolves in the pack, get to mate and get to mate with each other.  The other females in the pack might become pregnant, but they will be attacked if they try to mate with the main breeding male.  The only way they ever get pregnant is by wandering interlopers who haven’t yet formed a pair bond with a female.

During the mating season is when young wolves typically leave their parents’ pack.  They typically don’t have any mating opportunities, and the constant bickering wears on them.

The big and strangely shaped bacula of dire wolves suggests they might not have been quite like modern wolves.  These bacula are suggestive that dire wolves were “better endowed” than modern wolves, and larger genitalia is usually associated with a less physically competitive reproductive strategy.

This phenomenon is well-known in primates. Generally, if a monkey or ape has bigger testes or penis, there is going to be less physical confrontation when it comes to mating.

The competition for well-endowed monkeys is how much semen a male can produce and how far up in the female he can penetrate it. If you can produce more semen and get it deeper into the female’s reproductive tract, then you’re more likely to pass on your genes.

In less-endowed species, there is much more physical confrontation to get one’s genes passed on.

My guess is that this applied to dire wolves. They may not have even had a proper pair-bonding system, and a dire wolf bitch may have mated with many partners in much the same way female domestic dogs do.  The male dire wolves may have had very little competition for mating. They just mated and got along with each other.

It would have been an asset in a dire wolf pack for males to have gotten along with each other. More peace in a dire wolf pack means that more wolves remain in the pack for a longer period of time, and that means they would have had larger packs that would have been much more capable at hunting large prey. They also would have been better able to run off short-faced bears from their kills and to compete with Smilodons and American lions.

It’s likely that the intense competition between huge carnivorans during the dire wolf’s reign forced them into a more cooperative breeding and pack structure.

Again, no scientist has ever seen a dire wolf or observed their pack behavior, but they had this weird adaptation that sort of points to a more peaceful pack existence than exists in the modern species.

My guess is that dire wolves traveled in massive swarms, much like those seen in dholes of today. They were ruthless scavengers and dogged hunters.

When mating tame came, they bred like village dogs. Males would bunch up around a bitch in heat and each would mate with her. There would be no pair bond between the male and female.

The competition was in the semen and the implantation thereof.

 

 

 

 

 

 

 

 

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brush wolf

It cannot be overstated how much the discovery that coyotes are not as distantly related to wolves as we believed ultimately questions our entire understanding of the evolution of the Canis species.

The traditional understanding Canis species evolved from some form of Eucyon dog some six million years ago. Wang and Tedford, who wrote the most important book on the paleontology of the dog family, believe this was Eucyon davisi, which was the first of its genus to enter Eurasia. The genus Eucyon is where the common ancestor of the Canis dogs (including Lycaon and Cuon) and the South American wild dogs would be located. Eucyon dogs were small. Imagine them as being something like a black-backed jackal or a Hoary fox rather than a coyote.

Then, 5 million years later in the Southwestern US and northern Mexico, a coyote-like Canis evolved, which was called Canis lepophagus. This animal is sometimes considered the common ancestor of wolves and coyotes. It may be, but considering how close we now know wolves and coyotes are now, it’s not the most recent common ancestor. Canis lepophagus did migrate into Eurasia, where it either founded or is identical to Canis arnensis.

In Eurasia, several smaller jackal-to-coyote forms evolved. One of these was Canis estruscus,  which then evolved into Canis mosbachensis (which is called Canis variabilis in China).

Ron Nowak believed the red wolf was an offshoot of this wolf that wound up colonizing North America and then becoming isolated from the rest of Canis mobachensis when the ice sheets expanded. There was also a competing view that the red wolf was actually a remnant version of Canis edwardii or Canis priscolatrans (which were probably the same animal). This animal was roughly the size of a red wolf, but Nowak rejected it as a red wolf ancestor because it lived too early for what he thought were red wolf fossils.

The Eurasian wolf species evolved mosbachensis-variabilis, but the two forms of wolf shared habitat and likely exchanged genes, making it very difficult

The coyote’s evolution was never clear. It was thought to have evolved out of Canis lepophagus. It was thought that lepophagus evolved into edwardii, and then it began to become more gracile and smaller, eventually becoming the now coyote.  It’s now pretty clear that it evolved out of the Eurasian Canis lupus and not these endemic North American “wolves.”

It either evolved from the modern wolf, which evolved into roughly its current form 800,000 years ago, or it came from a late surviving mosbachensis-type wolves that were regularly crossing with modern wolves before they came into this continent. Maybe the remains that Nowak had been considering “red wolves,” were actually these ancestral wolves that were evolving into the modern coyote.

Maybe when this wave of wolves came back across from Eurasia, perhaps 50,000-100,000 years ago, it came into a world already dominated by a dire wolves, which already occupied the niche for large, pack hunting canids and this wave of Canis lupus evolved as the American jackal.  After all, the bobcat is just a diminutive Eurasian lynx that found itself in a very similar position when it came into this continent, and it evolved to be a smaller animal that generally hunts smaller quarry than its larger ancestor. Of course, the modern bobcat didn’t reach its current form until about 20,000 years ago, but it still was forced to adapt to a slightly different niche than its Eurasian ancestor.

In literature on the paleontology of Canis, there is a heated debate as to how these animals all fit. The conventional view is that the wolf evolved from Canis mosbachensis/variabilis through Canis etruscus, which may be the same thing as Canis edwardii/ Canis priscolatrans. Wang and Tedford contend that the coyote and wolf split from Eucyon.  The modern wolf evolved from Canis chihliensis, which was a large wolf-like canid. It spread into North America to found Canis armbrusteri, which then evolved into the dire wolf (Canis dirus) in North America and Canis gezi and Canis nehringi in South America.  In the Old World, another offshoot of chihliensis gave rise to Canis falconeri, which the supposedly gave rise to the Xencyon, which is supposed ancestor of the dhole and African wild dog. Another view holds that the Armbruster’s wolf (C armbrusteri) is descended from edwardii/priscolatrans (which may be the same as etruscus). This lineage then gave rise to the dire wolf and the two sister species in South America, thus descending solely from North America wolves.

All of these ideas come from paleontology, and they pretty much are done without looking very deeply into the studies that are examining the DNA of these species. It is pretty obvious from that literature that the notion that coyotes and wolves split at the time of the Eucyon ancestor is quite wrong. For that hypothesis to work, African of  wild dogs and dholes would have to be genetically closer to wolves than coyotes and golden jackals are. They aren’t.

But if the genome-wide analysis shows that coyotes are so much more closely related to wolves is true, then all these fossil and subfossil canids that are said to be the most recent common ancestor of wolves and coyotes simply aren’t.  Instead, all of these species that are classified in Canis are likely a mix of evolutionary dead ends, like the dire and Armbruster’s wolf, or could be hidden ancestors of extant canids that aren’t wolves or coyotes.

For example, black-backed and side-striped jackals diverged from the rest of Canis and its allies at about the same time that Eucyon was diverging from Canis. It is possible that there are many relatives of these particular dogs that are hidden in this vast sea of Canis fossils.

The new discovery about the coyote’s split from the wolf also means that any remains of North American canid that are listed as coyote that date to 1 million years before present are not coyotes. What they actually were is a very good question.

We’ve spent a lot of time assuming that coyotes and wolves were quite divergent. We know now that they really aren’t, but when we look into the past at all the “wolves” and “coyotes” that came before, we see how this genus became so successful. It can easily evolve into big game-hunting forms, but the real success is in its ability to assume the size and shape of the generalist predator. Phenotypic plasticity is a wonderful thing for a lineage to possess.

But the real message of the new discovery about wolves and coyotes should be is a cautionary tale about paleontology. Paleontology is a wonderful science, and it makes amazing discoveries every day, but when its faced with a lineage of animals where phenotypic plasticity and tendencies toward parallel and convergent evolution are commonplace, it is bound to make errors. Paleontologists aren’t examining flesh and blood that can have its molecules tested for relationships. They are measuring anatomical characters and determining phylogenetic relationships based upon the similarities of these characters.

Which works well.

Until you get something like wolves and coyotes, where there are many ancient fossil and subfossil remains that look like they could be ancestors of either.

But the DNA says they aren’t.

And paleontology would have problem catching the inverse. There are many species that we’ve discovered only through DNA testing. African butterfly fish in the Congo and Niger basins look identical to each other, but they have been isolated from each other for 57 million years. I have yet to see this species split into two, but if they were mammals, you could bet they would be placed in distinct species in heartbeat.

Paleontology is missing some really important things we’ve since found out through molecular analyses.

And paleontologists know this.

They are working with the data they have, and by definition, it’s going to be more incomplete than genetic studies.

Science is provisional. Different disciplines and methodologies are going to come up with different answers. It’s pretty amazing that one genome-wide assay study can wipe out so much literature in paleontology.

These debates have been raging for years.

And it turns out that everyone was actually wrong.

Update 21 August 2016:  It turns out that I missed a paper that actually did some limited DNA analysis and found that Canis nehringi was pretty much a South American dire wolf, as in it was likely the same species as the North American dire wolf. Canis gezi, however, was  more closely related to the modern maned wolf and had been incorrectly identified as a wolf. So let this stand as a correction to the error above.

 

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The description of the paper comes from Facebook via Jess Ruffner:

Jeff Saunders has been looking at canids from Clovis sites. He presented results of his work on sites in southern Arizona at the Plains Anthropological Conference in October. He noted the presence of a diminutive form of Dire Wolf in these assemblages. Could this be evidence of early dog domestication in North America? We’ll be exploring this topic in more detail over the next few months. Stay tuned.

I don’t have a copy of the paper, but if I can see a copy, I’d be very grateful.

But am I surpised?

Heck no!

I’ve already discussed the possibility of the Hare Indian dog being a domesticated coyote, and there were lots of domestication attempts with wild dog species.

Only the Eurasian domestication experience with Canis lupus, the Holarctic wolf, ever actually amounted to much.

If these animals are dire wolves, then I have always had some questions about dire wolves.

Were they actually a unique species or were they nothing more than an early wolf subspecies that evolved to be really robust? And exactly how are they related to modern wolves and domestic dogs?

Most early wolf subspecies were not particularly robust, but they later did evolve into big hulking things, including a subspecies that lived in Alaksa during the Pleistocene. This wolf subspecies, though clearly within Canis lupus, but it was more robust and had very powerful jaws that were designed for hunting very large prey. These are the exact same adaptations that the dire wolf, which lived from the Central US to Northern South America, possessed– and for exactly the same purpose.

I also wonder if dire wolves became extinct entirely or if they contributed genes to modern wolves, dogs, and coyotes. If they contributed to Native American dogs, then they are likely lost, but if they contributed to wolves or coyotes, they could still have some traces of their dire wolf ancestry. I am assuming, as is most likely from observing their modern relatives, that dire wolves were fully fertile with both Canis lupus and Canis latrans.

I have not seen any comparative studies of dire wolf dna of any sort with those of modern members of the genus Canis.  Most studies on dire wolf taxonomy glean their analysis from comparative morphology– which is quite a dubious undertaking when we’re dealing with the dog family (see the red wolf debacle!)

So there are these questions.

And the fact that we have some evidence that Clovis people domesticated dire wolves is certainly intriguing.

***

The animal featured in the image above isn’t a domesticated dire wolf.

No.

It’s actually a recreated dire wolf, which is the American Alsatian breed.

Derived from mostly German shepherd stock, its breeders have tried to turn it into something like a dire wolf in phenotype.

 

 

 

 

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Source.

This post is a hoax.

Do not quote it as fact.

It is nothing more than an April Fools’ Day hoax.

The only part of it that is true is that my great great grandparents’ homestead is on Lower Run. There is a hunt club nearby, but it is on the Calhoun County side.

I hope there is no Ken Olsen who works for the US Geological Survey, because the one in my post was entirely fictitious. His name comes the late Stanley Olsen, who was an expert on ancient dog remains that were found in archeological digs, and then I played around with Stanley to get Stan and finally Ken.  If it had existed, I am sure Stanley Olsen would have loved to have examined that dire wolf skeleton. But that’s as far as the resemblance goes.

Dire wolves went extinct in the great extinction that happened in North America about 12,000 years ago.  It is unlikely that anyone will find one younger than10,000 years old.

I deleted a comment by Lane Batot yesterday, mainly because I wanted to see how many people would fall for the post.

(Please forgive me. I am juvenile.)

Lane was interested in exactly what a dire wolf was, and if we had a good DNA sample, we could figure out where these animals fit in the genus Canis. Lane was interested in knowing if it might be possible that dire wolf genes could be in modern North American wolves.

Good question!

I’m going to some posts on the evolution of Canis in the next few days.

***

I hope you can forgive me for my antics. I’m from West Virginia, and April 1 is taken very seriously here.

And I am not the only person who has engaged in these sorts of internet hoaxes.

My favorite hoax is the one on Minnesota bull sharks. It is the gold standard in these April Fools’ pranks.

However, it is not the only good one.

Last year, the Carolina parakeet was rediscovered.

Now, these things aren’t that hard to write.

It just takes a bit of pseudo-knowledge and a bit of imagination to write a piece of Grade A bull-plop.

So if you see something fantastic on this blog on April 1 again, it may not be true.

Remember, I am not without a sense of humor. I hope that you don’t get too angry with me over this revelation.

***

This is the supposed range map for the dire wolf. West Virginia wasn’t part of its range:

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