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Posts Tagged ‘golden jackal’

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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African golden wolf (Canis anthus).

African golden wolf (Canis anthus).

A study was released today in the journal Current Biology that will radically change how we classify the genus Canis.

Using genome-wide analysis, researchers led by Klaus-Peter Koepfl found that African golden jackals, including those that have recently been classified as African wolves (Canis lupus lupaster), are all genetically distinct from Eurasian golden jackals.

But they are also distinct enough from wolves to be considered their own species, which has been posited as Canis anthus, the African golden wolf. Previous studies had suggested that certain African golden jackals were actually a primitive form of wolf, but these studies were based upon mitochondrial DNA alone.

This study compared a relatively large sample of nuclear DNA from several related Canis species, and it found that golden jackals of Eurasia and those of Africa were not even closely related to each other. African golden jackals split from the coyote/wolf lineage some 1.3 million years ago, while Eurasian golden jackals split off about 1.8 million years ago.

This pretty much ends the question of Canis lupus lupaster, but it does create an interesting question.

In the Guardian‘s article on the study, Koepfli thinks that the reason these two species, the golden jackal of Eurasia and the African golden wolf,  were considered the same species is because of parallel evolution.

I actually disagree with this assessment. If you go back and start looking at fossils of old wolf-like canids, they all start to look very jackal-like.

Indeed, as I’ve pointed out here many times, the black-backed and side-striped jackals are quite genetically divergent from the other wolf-like canids. They are more genetically distinct from the rest of Canis than the African wild dog and the dhole are, and both the dhole and African wild dog each has its own genus. (My remedy for this paraphyly in Canis is to put the dhole and African wild dog in Canis,  but it also could be solved by creating a genus for the side-striped and black-backed jackals, which is what I think the move will be).

The reason why these two jackals look like both forms of golden jackal and the coyote is that all of these animals represent primitive forms of Canis.  The ancestor of the large northern wolves that everyone knows was a coyote- or jackal-like canid, as was the ancestor of the African wild dog and the dhole.

“Primitive,” as I am using it here, means that an animal retains traits of the ancestor that sister taxa have lost. So in this perspective, the various jackal and coyote species still look very much like the common ancestor of all Canis.  This type of dog is quite versatile, for it is big enough to defend itself from many other predators but it is small enough to subsist on rodents and carrion.

So now, genome-wide studies have done the following to canid taxonomy:

1. Found that the eastern wolf and red wolf are recent hybrids between wolves and coyotes and are not actually an ancient wolf species.

2. Found that red foxes in North America may be a distinct species from those of Eurasia and North Africa

3. Found that there are two species in what we used to call the golden jackal: the African golden wolf and the Eurasian golden jackal, which we might just drop to “Eurasian jackal” for common nomenclature.

So we’ve lost two species in the dog family and gained two.

And I would argue that we should recognize the tanuki of Japan as a disctinct species from the rest of the raccoon dog species, and I would also argue that the island fox of the Channel Islands is a subspecies of the mainland gray fox. It is far less genetically distinct from the gray fox than the domestic dog is from the wolf.

We also need to do similar studies on South Indian and Himalayan wolves, which have distinct mtDNA lineage.

I would really like to know what the genome-wide analysis would reveal on those two wolves.

I would also like to see an examination of black-backed and side-striped jackal populations, because I suspect there is some interbreeding where the ranges of the two species overlap.

Jackals have never been really interesting to scientists studying the dog family, but it is likely that the first canids that wandered the camps of our hunter-gatherer ancestors were black-backed jackals. It was their barks that alerted us to approaching leopards, and they got to lick some of our pots and eat some offal.

But they never made the same leap that wolves did. It is for this reason alone that I think one should be skeptical of hypotheses on dog origin that rely upon scavenging and the inheritances flight distances alone as the determining factor. No one has seen a spotted jackal of any species or one with floppy ears, but they are the world champions of scavenging.

Jackals just lack the charisma of the larger dog species, but I do know that if I ever get to Africa, the first species I want to see is the black-backed jackal. Then we’ll worry about the big cats.

Yep. I’m that much of a canid enthusiast!

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Kent Hovind is out of prison, and seeing as he has a month of home confinement to waste time on the internet, he has been posting daily Q and A sessions on Youtube. Just e-mail him, and he’ll answer your question on Youtube.

So the other day, I sent him an e-mail with the following question:

Scottie Westfall Jul 22
To
TheDrDino@gmail.com (Kent Hovind)
Would you say that black-backed jackals, side-striped jackals, African wild dogs (Cape hunting dogs or painted dogs) and dholes (Asiatic wild dog) are part of the same kind that includes golden jackals, coyotes, wolves/domestic dogs/dingoes, and Ethiopian wolves?

Why would I ask this question?

Well, within the wolf-like canids, it is well-known that some species are still chemically interferitle. We have a nice phylogenetic tree, which was drawn from a sequencing of domestic dog genome:

dog family phylogentic tree

Domestic dogs are basic a type of “grey wolf,” so they certainly do interbreed.  One could make the case in a creationist sense that these animals are all part of the same “kind,” because a “kind” is generalized term that pretty much is based solely on whether they can “bring forth”– produce offspring. Wolves and dogs have interbred and produced fertile offspring with coyotes and golden jackals. Golden jackals and coyotes have done the same. Ethiopian wolves (which are a really specialized canid that is found only in the Ethiopian Highlands) have interbred with domestic dogs, and in some instances, there have been viable, fertile hybrids produced.

By the Biblical definition of kind, these animals fit.

However, interfertility stops with the Ethiopian wolf. Although there are rumors of hybrids being produced between dogs and dholes and between dholes and golden jackals, we have no verified hybrids. There are claims that the Bangkaew dog started out as a dhole/domestic dog hybrid, but I’ve never seen anyone confirm this ancestry in the breed.

When this phylogenetic tree was drawn, it really did change the way we view jackals. When I was a kid, we tended to think of all the jackals as being closely related. We even called the Ethiopian wolf the “Simien jackal.”  But even before this study came out, it was pretty clear that the canid of the Ethiopian Highlands was closer to the wolves than the other endemic African jackals.

But this study revealed that golden jackals are even more closely related to wolves/dogs and coyotes than to the other jackals, and that the two endemic African jackals, the side-striped and black-backed jackals, are actually more distantly related to the interfertile canids than African wild dogs and dholes are. African wild dogs and dholes have traditionally been given their own genus names (Lycaon and Cuon), but those two endemic African jackals have always been listed as part of Canis. We now think of Canis as a paraphyletic grouping, which means it is not a clade. To make it a clade, we would have to move the African wild dog and the dhole into Canis, which is what I would do, or create a new genus for the two endemic African canids.

In an earlier video, Kent Hovind was answering a question about the kinds of animals on the ark, and he said something along the lines of how jackals, wolves, coyotes, and dogs are all descended from a single dog “kind” that was put on the ark.  (In that video, Hovind actually claimed that hyenas were part of the dog kind, which isn’t even close to being true).

But if a “kind” is defined as what can produce offspring, we have a very hard big problem here. When a creationist says “jackal,” I don’t think they understand that the three species of jackal are actually quite distinct from each other. You cannot breed a black-backed jackal to a dog, even if people claim that basenjis are derived from them, or that they have an African village dog that looks like one. The two species are very distinct from one another.

So if these animals all are distinct kinds, then God had Noah put several ancestral Canis-type dogs on the ark.  Black-backed and side-striped jackals probably can interbreed, but their genomes haven’t been studied in the interfertile Canis species have been. So that would be a kind. Dholes and African wild dogs probably can hybridize as well, so that would be another kind. And then you’d have the classic “dog kind, ” which has all the wolf-like species that hybridize a lot.

So we’d have these three separate kinds, but why?

Wouldn’t an intelligent deity just want one dog kind?

I mean, a Western coyote and a black-backed jackal are essentially the same organism in terms of their behavioral ecology. They hunt small animals. They gang up and hunt ungulates, and they do a lot of scavenging. They both have intense pair bonds, and they do cause problems with livestock producers.

Why would there have to be two separate “kinds” for this mid-sized, generalist canid?

Well, Hovind tried to answer my question, and he did very poorly. Now, I must confess that he was answering a bunch of questions about the flat earth and geocentrism (which many of his most devout followers wish he believed in), so I don’t think he was expecting a question like mine or understood its significance.

Here’s his answer (and he thinks my name is Daniel):

Source.

He tells me to go look up Baraminology, which I did.

But when I went to Answers in Genesis, I found that they fell into exactly the same trap as Hovind.

They point out that there was a discovery a few years ago that there were some “golden jackals” in Africa that were found to be a primitive lineage of wolf. Now, these are not Ethiopian wolves. People mess this up all the time. These are African wolves (Canis lupus lupaster), and they are actually pretty widespread. Populations of these wolves have been found as far from Ethiopia as Senegal, and they do cross with golden jackals there.

But note that the African wolves are breeding with GOLDEN jackals, and they were being confused with GOLDEN jackals. We know that golden jackals are close to wolves and domestic dogs, and they do hybridize.

One could make the case that golden jackals are part of the same “kind” that includes dogs, coyotes, and wolves, but you cannot say that black-backed and side-striped jackals are part of this same kind. They no more can cross with dogs than they a dog can with a petunia or a guinea pig.

So if you hear a creationist talking about jackals being part of the same “kind” as domestic dogs, just ask them about black-backed and side-striped jackals.

They don’t understand the problem with their reasoning at all.

Nor do they care.

***

AronRa has a nice video on canid evolution, though I do have few quibbles about it, such as the location of where dogs were domesticated and the size of some borophagine dogs, it gives you a good understanding of the problem when creationists mess around with interfertility in dog species.

Source.

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Egyptian jackal or African wolf with golden jackal and wolf-like features.

Egyptian jackal or African wolf with golden jackal and wolf-like features. From “Roosevelt in Africa” (1910).

One the strange ironies about dogs is that we have set up a system in which populations are maintained without regular influxes of new blood. However, at no point in the evolutionary history was this ever the case.

Some dog fanciers maintain breeds as if they were distinct species, and in some breeds, one can find lore that they are derived from sort of wild canid that has nothing to do with wolves or the rest of dogdom. Chihuahuas are supposedly domestic variants of the fennec fox. The Japanese chin was said to be distinct species that belonged to its own genus.

But no matter how you slice it, domestic dogs are all one species, and what is even more important, the more we have found out about the genome and that of their closest relatives, the harder it becomes to think of them as a distinct species from the wolf.

And if that weren’t such a revelation, it really gets more bizarre when we have no learned that wolves, golden jackals, and coyotes are not the cut-and-dry species we assumed them to be. In Eastern Canada and the Northeastern US and Midwestern US, we have discovered that wolves and coyotes have hybridized a whole lot more than we realized. We have also found evidence that golden jackals and wolves have hybridized in Bulgaria. Both coyotes and golden jackals can cross with wolves or domestic dogs and produce fertile offspring.

To make things more complicated, it turns out that wolves and golden jackals have continued to exchange genes since the two species separated. A recent genome-wide study of modern dogs, wolves, and golden jackals revealed that Eurasian wolves and golden jackals continued to mate with each other after their initial separation. The authors found substantial gene flow between golden jackals and Israeli wolves, as well as the ancestral population to all wolves and domestic dogs.

Most North Americans are aware of the taxonomic controversies involving coyote and wolf hybrid populations, including the red wolf and the proposed “Eastern wolf” species, but it turns out that this problem also exists in the Old World.

There is now a debate as to whether certain sub-Saharan  and North African golden jackals are golden jackals or wolves. A few years ago, there were several studies that suggested that the mitochondrial DNA of certain African golden jackals were actually those of a primitive wolf lineage. There is still some debate as to whether these animals are wolves or jackals, and some of the proposed wolves have been found to hybridize with golden jackals in Senegal.

In utter ignorance of the natural history of wild Canis, domestic dog fanciers have spent the past century to century and half splitting up gene pools under the delusion that this somehow preserves them.  Never mind that for most of their suggested 2 or 3 million years on the planet, wild wolves have continued to exchange genes with their closest relatives. When species hybridize, it was always thought that this would be a negative, but in truth, hybridization can be source of genetic rescue. In the case of Eastern coyotes, crossing with wolves can introduce new genes for more powerful jaws and larger size, which make them better predators of deer. It can also introduce new MHC haplotypes, which can provide the animal with enhanced immunity to disease.

One way of looking at golden jackals and coyotes is they are actually themselves primitive wolves. This might sound a bit heretical, but if you were to go back into time and find the ancestor of all wolves, golden jackals, and coyotes, it would look more less like a golden jackal or coyote.  I would argue that these animals represent a sort of generalized template from which larger, more specialized forms can evolve. One of the problems in sorting out wolf, coyote, and jackal lineages from the fossil record is that at various times through their history on the planet, different lineages have evolved larger wolf-like sizes or have produced coyote or jackal-like forms to fit the niche in question.

A recent comparison of golden jackals, African golden jackals that might be wolves (Canis lupus lupaster or Canis lupaster), black-backed jackals, modern wolves, and the extinct Canis etruscus and Canis arnensis revealed that those the proposed African wolves had skull morphologies that were closer to known golden jackals and black-backed jackals. If these lupaster canids are actually wolves and not jackals, then we would have never been able to guess their identity upon morphology alone.

So while the dog fancy has been splitting hairs and arbitrarily dividing up gene pools, science has revealed that the wild dogs haven’t been doing the same.

Canis is not a closed registry.

Even the boundaries between wolves and golden jackals and between wolves and coyotes are blurry, and of course, this leaves out the rather significant gene flow that has occurred between domestic dogs and wild wolves. Black wolves and wolves with dewclaws on the hind legs are the result of dogs and wolves mating “in the wild.”

Science has found all of these wonderful things out, but the dog fancy remains stuck in another era.

Maybe someday it will move beyond the closed registry system and instead of offering up the bromide of “breed preservation,” it will adopt a system of “breed management,” which strives to maintain genetic diversity within a breed and allows regular influxes of outside blood.

That is what nature has allowed with the wild Canis.

That is the actual story of the animals of this genus. It is not one of one lineage remaining pure for millions or even thousands of years.

It is about significant hybridization.

And Canis is not the only genus with this hybridization issue. Ducks in the genus Anas hybridize quite a bit, and it is well-known that many species of whales and dolphins hybridize with their close kin as well. All of these animals are fairly mobile organisms, and their mobility is likely why they retain so much interfertility.  They simply cannot be reproductively isolated from their closest relatives long enough for them to lose chemical interfertility.

It is not something that should be thought of as an evil. Instead, it’s actually a major strength. It is one our own species utilized when we exchanged genes with the Neanderthals and Denisovan people, and if there were another human species alive today, we would likely be able to cross with it.

But because we are so alone in this world, it is difficult for us to understand the concept of a species complex. We are the only humans left.

But dogs and wolves are not the last of their kind.

The gene flow between wild and domestic and among the these three species of Canis is something we have difficulty imagining.

But it is the story of dogkind.

 

 

 

 

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Trail camera photo of a golden jackal in Estonia. Source.

Trail camera photo of a golden jackal in Estonia. Source.

One story that has missed much of the English-speaking press and English-speaking scientists is that the golden jackal’s range in Eastern Europe has now expanded to the Baltic nations of Latvia and Estonia.

Golden jackals don’t get much billing in the world of wolf-like canids, but they are closely related to wolves and coyotes. Indeed, one way to think of golden jackals and coyotes is they both represent rather primitive lineages of wolves, ones that are much smaller the typical wolf and retain the primitive body language, especially the gape threat. Both coyotes and golden jackals are chemically interfertile with wolves and domestic dogs

These smaller, more primitive wolves are actually doing pretty well and have expanded their range. Coyotes in North America now range from Alaska to Newfoundland down to southern Panama, and the golden jackal, which ranges across northern and East Africa across southern Asia to Cambodia, is also expanding its range.

Historically golden jackals made it up into the Caucasus and into the southern Balkans and Greece. They were well-established in the reed marshes of Hungary for several centuries, where they were called “reed wolves.”

However, in the past few decades, golden jackals have spread northward into Austria,  Slovakia and Southern Poland.  It was thought that these jackals would be unable to go deep into Eastern Europe, simply because golden jackals were thought to be unable to handle the cold very well or wolves would check their advance.

In 2011, though, something strange happened, a woman in Western Estonia (Lääne County heard unusual howls in the night.  In that a wildlife researcher named Liisi Laos found the tracks of unusual canid tracks in the same region. These tracks came from four individuals, and they were thought to be golden jackals.

In 2013,  hunting dogs killed a jackal, and now, it’s pretty much accepted that golden jackals are in Western Estonia.

Their range has also expanded into nearby Latvia, where they were confirmed last year.

The questions about these jackals are rampant. Because there was no record of jackals in northern Poland or in Lithuania, it was suggested that someone brought them in to Estonia. However, that suggestion seems less likely because it turns out that jackals are in Ukraine and Belarus. That means that the jackals of the Baltic could have come up from Romania or southern Poland into Ukraine and then up through Belarus into Latvia and Estonia. (Which would be the reverse of where they were first documented).

The reason these jackals remained undetected is because this region is not heavily populated. Eastern Europe is much, much wilder than the West, and the golden jackals could have been mistaken for young wolves and generally ignored.

There is some suggestion that climate change has allowed these golden jackals to colonize such a cold part of Europe, and there may be something to it. However, this part of Europe has much harsher winters than Western Europe, which means they could be on their way to colonizing all the way out to France, Spain, and Portugal.

Modern Europe isn’t such a bad place for a jackal, and we do know that a jackal-like canid lived in Europe during the Pleistocene. It was called Canis arnensis, and it could have been an ancestor of the golden jackal.  So there is some precedent for these sorts of canids in Europe. Indeed, one of the proposed ancestors of the modern wolf is Canis mosbachensis, and it was not much larger than a European golden jackal.

So maybe conditions are favorable for a little primitive wolf to colonize Europe once again.

And before anyone freaks out, I’ll just give you an idea of the size of the golden jackal in Europe.

This is a photo of an individual that was killed in Bulgaria.

European golden jackal size

We’re not even talking Eastern coyote-sized animals, but they could be important competitors for red foxes and the invasive raccoon dogs that have spread throughout the region.

So Europe might have its own little coyote very soon!

 

 

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"You guys don't want any. it tastes like ass."

“You guys don’t want any. It tastes like ass.”

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Melanistic golden jackal and normal-colored mate.. Photo courtesy of Can Bilgin and Hüseyin Ambarlı.

Melanistic golden jackal and normal-colored mate.. Photo courtesy of Can Bilgin and Hüseyin  Ambarlı.                                                

Melanism in dogs, wolves, and coyotes has been a source of great interest to molecular biologists in recent years.

For example, it has been confirmed that black coyotes and black wolves in Italy and North America gained their black coloration through cross-breeding with domestic dogs.

But domestic dogs have two variants of melanism. The most common form– and the type found in Italian and North American wolves and coyotes— is inherited via dominant allele. But there is another form, which is related to the sable coloration, that is inherited via a recessive allele. This recessive black may have been indicated in at least one Russian wolf, but all modern black wolves that have been examined thus far have turned out to be dominant blacks that inherited their black coloration from the introgression of domestic dog genes.

However, a recent discovery of a black golden jackal in northeastern Turkey might be the first example of a melanism in an interfertile Canis species that did not originate in the domestic dog.

Between February 2009 and April 2010, a camera trap near the city of Artvin captured images of this black golden jackal and its normal-colored mate.

The documentation of this jackal appears in the journal Mammalia in December 2012, and the authors suggest that this jackal likely did not receive its black coloration from its ancestors crossing with domestic dogs.

Although golden jackals and domestic dogs are interfertile, cross-breeding between them in the wild has not been documented– though it certainly is possible. The black coloration in red foxes is entirely unrelated to any of the black coloration in domestic dogs, and it is likely that this black jackal is the result of an entirely different mutation that has not yet been documented.

Unfortunately, no physical samples from this jackal exist, so we cannot know for certain what genetic mechanism made this jackal black.

As far as I know, no further black golden jackals have been documented in the area, so this individual either left no offspring or it is inherited via a recessive allele– and thus different from the dominant black in wolves and coyotes.

 

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A side-striped jackal (Canis adustus), the jackal no one talks about.

We’ve always called the smaller wild dogs in the genus Canis jackals.

Historically, there were four species of jackal:  the golden (Canis aureus), the black-backed (Canis mesomelas), the side-striped (Canis adustus), and the Simien (Canis simensis).

Some authorities considered they coyote (Canis latrans) to be a jackal, usually called “the American jackal.”

At one time, they were all placed in the genus Thous.

This, of course, assumed that these animals were all closely related to each other.

However, as we’ve looked at DNA analysis, the relationship between jackals shows that the term “jackal” is actually quite meaningless.

In 1994, an mtDNA study revealed that the Simien jackal had certain mtDNA sequences that were more similar to wolves than other jackals. It was thought to be a relict population of primitive wolves that came into Africa during the Pleistocene.

And from that time forth, the English name of this species was change to “Ethiopian wolf.”  I don’t call it anything else.

However, as more work was performed on jackals, certain facts became evident.

Initial studies of black-backed, side-striped, and golden jackal mtDNA revealed that black-backs in East Africa had huge variances in their mtDNA. Golden jackals had mtDNA that was most similar to coyotes and wolves, while black backs and side-stripes were more similar to each other.

And then the phylogeny of the dog family was drawn from a high-quality sequencing of the dog genome revealed that golden jackals were much more closely related to coyotes and the wolf and domestic dog species than the Ethiopian wolf was. We still call them Ethiopian wolves, even though golden jackals are more closely related to actual wolves than those animals are.

The other issue revealed through this research was that Canis, as it is traditionally classified, is a paraphyletic genus. Modern taxonomy is generally concerned with classifying animals according clades. Clades are, by definition monophyletic. That is, they contain all the animals that descend from a particular lineage.

The dog genome research revealed that two species that are never traditionally classified as being part of Canis, the African wild (Lycaon pictus) and the dhole (Cuon alpinus), actually should be included there.  It turns out that black-backed and side-striped jackals are more distantly related to the rest of Canis than these two species are.

And if we classify Canis with all the jackals, the Ethiopian wolf, and  the wolf and dog species and leave out the dhole and African wild dog, we’ve created a paraphyletic genus that is not useful to modern taxonomy.

Some have suggested giving the two endemic African jackals their own genus.

And this would make Canis monophyletic without including the African wild dog and dhole.

However, the genus that would remain would include several species that are all chemically interfertile with each other (at least in theory). Species complexes exist throughout that part of the Canis, and delineating species is very difficult the species in this lineage.

Although Robert Wayne at UCLA has suggested that black-backed and side-striped jackals might be able to interbreed, no one has confirmed a hybrid between these two species. African wild dogs might be able to hybridize with dholes, but because they live on different continents and because they are both fairly endangered, no one has attempted to cross them. (There are persistent rumors that dholes can cross with domestic dogs. One dog breed, the Bangkaew dog from Thailand, is said to have derived from a dog/dhole cross. However, I don’t believe this claim has ever been tested through DNA analysis.)

All this research has revealed that how we have traditionally thought about the dog family is probably wrong.

The golden jackal is actually a primitive offshoot of the wolf lineage, just as the coyote in the New World is. The Ethiopian wolf is an even more primitive offshoot.

The two endemic African jackals are the two oldest living species in the Canis lineage. They are even more distinct from this lineage than dholes and African wild dogs are.

We do not have a good replacement word for jackal.

I’ve suggested that we call golden jackals “Old World coyotes” almost as a joke.

But I don’t have a good name for either of the two remaining jackal.

Because black-backed jackals are so scrappy, I’ve even suggested that we call them “wild Jack Russells.”

Whatever we call them, the term jackal, if it’s used to reflect close relationships between species, is utterly meaningless.

With the exception of the two found only Africa, it doesn’t refer to any animals that have a close relationship with each other.

It’s just a term we use for smaller wild dogs that are in some way related to wolves.

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Canis lupus lupaster, the African wolf. Photo by Cécile Bloch.

It wasn’t long ago that wolves were thought to be found only in Europe, Asia, and North America.

However, there were always wolf-like golden jackals that had scientists perplexed for many years.

Earlier texts listed these animals as Canis lupus lupaster, usually called the Egyptian wolf, but by the late twentieth century, it was assumed that they were nothing more than wolf-like golden jackals. The scientific name for this wolf-like golden jackal was Canis aureus lupaster.

Then, in the January of last year, a study that compared the mitochondrial DNA of wolves and golden jackals, including these wolfish ones, revealed that the wolfish jackals were not golden jackals at all.

Instead, it was found that they represented a primitive mitochondrial lineage within Canis lupus.

So they were wolves after all.

However, that study also revealed that these wolves were also found in Ethiopia. Not to be confused with the critically endangered Ethiopian wolf (Canis simensis), the African wolves were an early branch of the Canis lupus species that invaded Africa and then became genetically isolated from the main wolf lineages of Eurasia and North America. This exact same issue exists with Himalayan and certain wolves from the Indian subcontinent. Their mitochondrial lineages are very old.

The discovery of Canis lupus wolves in Ethiopia was a bit of a shock, and the question that everyone want to know was exactly how extensive the African wolf’s range was.

Golden jackals are widely distributed over much of North and East Africa, as well as much of southern Asia, including the Caucasus, They are also found in the Middle East up into Turkey and into Europe as far north and west as Hungary.

However, there was a distinct possibility that some of these “golden jackals” were actually wolves.

And that’s exactly what has been found.

In the West African nation of Senegal, there are wolfish golden jackals and more gracile golden jackals.

And a recent study in PLoS ONE looked at some mitochondrial DNA samples from both types of golden jackal from Mali, Algeria, and Senegal and compared them with samples from wolves and other species from the genus Canis, including golden jackals from East Africa and India.  The study found that there were four main mtDNA lineages in Canis lupus:  a Holarctic wolf and domestic dog lineage, a lineage for certain wolves from the Indian subcontinent, a lineage that included certain wolves from the Himalayas, and an African wolf lineage.

Canids with the African wolf lineage were documented in Mali and Algeria, but the ones in Senegal were actually subjected to an intensive field survey.

It was discovered that the African wolves had very different body language from typical golden jackals in the region. African wolves are quite aggressive toward golden jackals, but they have different ways of expressing that aggression than one normally sees in golden jackals.

Wolfish threat posture from an African wolf (Canis lupus lupaster) on the left. More golden jackalish or coyote-ish threat posture from a Senegalese golden jackal on the right.

To make things even more interesting, it was discovered that some Senegalese golden jackals– animals that look and act like golden jackals instead of African wolves– have African wolf mtDNA.

That means that African wolves and golden jackals do interbreed.

And that also means we’ve just discovered a Canis lupus/Canis aureus species complex!

We still haven’t determined how much crossbreeding between golden jackals and African wolves has occurred, and we still haven’t looked at their nuclear DNA markets to see if they are more extensively crossbred with each other.

This study also found a wide variance in mtDNA between golden jackals in East Africa and India, which also needs to be examined.

The study found that African wolves are the oldest mtDNA lineage within Canis lupus.  It doesn’t necessarily mean that wolves evolved in Africa, but it does show that African isolation has done fairly good job in preserving this lineage.

These findings almost beg for a study that examines a large sample of nuclear DNA, if not something like the genome-wide comparisons that were performed on wolves and coyotes.

So wolves do exist in Africa, and they aren’t just in East and North Africa.

They are in West Africa, too!

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An Algonquin Park wolf. These wolves are naturally occurring hybrids between wolves and coyotes, not a unique "Eastern wolf" species as is commonly claimed. On average, they were found to share 58 percent of their genetic markers with wolves and 42 percent with coyotes.

One of the real problems in determining the exact taxonomy of the dog family is the interfertility that exist between certain species in the genus Canis.  The dog/dingo/New Guinea singing dog/Holarctic wolf species (Canis lupus) can interbreed with the coyote (Canis latrans), the golden jackal (Canis aureus), and the Ethiopian wolf (Canis simensis) and produce fertile offspring.  Coyotes and golden jackals have been interbred in captivity and have also produced fertile offspring, so it is likely that all of these animals can hybridize with each other. According to the phylogenetic tree drawn from sequencing the dog genome, the Ethiopian wolf was the earliest offshoot of the interfertile Canis lineage , diverging 3 to 4 million years ago. And of the  “interfertile four,” it  is the most distantly related to the Canis lupus species, which strongly suggests that all four species can produce hybrids.

Potential interfetility alone is not the test for determining species, so one should not make the error of claiming that all of these interfertile dogs represent a single species.

They don’t.

Each of these animals has a unique evolutionary history, and they don’t normally hybridize in the wild.  Wolves and coyotes only cross when wolf populations are very low, and the male wolves mate with female coyotes. It is very difficult to get a dogs and golden jackals to crossbreed, though there may be be some evidence of dog genes in golden jackal population. Only the Bale Mountains National Park Ethiopian wolves have been found to cross with domestic dogs.

But various historical records, show that dogs and wolves got it on regularly when wolf populations were much higher and dogs were given more liberty. In the Old West, the best way to kill a wolf was to use a bitch in heat to draw in the male wolves. While the two were tied, it was very easy to come in with an ax or club and dispatch the male wolf, who was literally caught with his pants down. Male dogs were often known to go running off during wolf mating season, and they often returned– usually quite worn out. Wolves have been known to kill and eat other wolves that come into their territories, which is often how they will respond if a dog shows up. But there are historical accounts that show that wolf and dog interactions are much more complex than one might assume. The wolf and dog are now regarded as conspecifics. The dog is now believed to have derived from Eurasian wolves, with Middle Eastern wolf subspecies provided most of their current genetic diversity.

Dingoes and New Guinea singing dogs are derived from domestic dogs that went feral in their respective countries. Some natives of Papua New Guinea have hunting dogs that are derived from “wild” stock, and different groups of Indigenous Australians used dingoes as hunting dogs. So we now consider these animals to be derivatives of the wolf, but their most recent ancestors were domestic dogs. which were derive from wolves.

That’s why I say the Canis lupus is the Holarctic wolf/dingo/New Guinea singing dog/domestic dog species.

The existence of domestic dogs worldwide has caused a lot of confusion in classifying these species. Domestic dogs vary widely in appearance, and if an usual wolfish creature was spotted, it was assumed to be something unique. In reality, these creaturesmay have been nothing more than an aberrant domestic dog or a hybrid with a domestic dog.

Domestic dogs have contributed some genes to wild populations. Black wolves and coyotes received their melanism through hybridization with black domestic dogs.   Modern wild dog species do not have dewclaws on their hind legs, but domestic dogs do. Italian researchers found that if they found any wolf with dewclaws on the hind legs, they could be certain that it had some dog ancestry.

Now, the notion that dogs and wolves could be the same species isn’t as hard to fathom as another concept that stems from the interfertility between species in the genus Canis.

In North America, there has been some amount of gene flow between the dog and wolf species and the coyote.

Although Canis lupus and Canis latrans don’t regularly hybridize, they have done so enough to fundamentally change the genetic composition of each other.

Perhaps the first study to reveal the importance of this hybridization was Robert Wayne’s study of wolf and coyote mtDNA, which suggested that some wolves were actually coyote hybrids.  This study revealed an extensive hybrid zone between wolves and coyotes in North America, which likely resulted when wolf populations were decimated and the remaining wolves were forced to chose coyotes  for their mates.  Wayne’s research also pointed to the distinct possibility that the much ballyhooed red wolf was probably a hybrid, and this finding was confrimed in a microsatellite analysis.

In the early 90’s, this finding was not necessarily well-received. Supposed red wolves had been captured in Louisiana and East Texas, and these animals had been bred for decades in order to be released into the wild. In 1987, some red wolves from this breeding program was released into the Alligator National Wildlife Refuge in Eastern North Carolina.  By the early 90’s, this program was one of the more successful attempts at restoring endangered species under the Endangered Species Act.

Further, another microsatellite analysis revealed that the wolves of Algonquin Park in Ontario, which had been thought of as being derived from wolf/coyote hybrids, were actually a unique species. Proposed as the Eastern wolf species (Canis lycaon), it was believed to the same species as the red wolf. If these findings were true, then the only wolves to live in the temperate regions of North America were a unique species. The only survivors of this species were the wolves that lived in parts of Ontario and Quebec and the red wolf.

Microsatellite and mtDNA analysis are biased samples. They examine only a tiny part of the genome, and it is possible for these studies to produce really bad results.

What was needed was a study of nuclear DNA.

Unfortunately, studies of nuclear DNA were quite expensive and labor intensive.

It has been only in the last two years that really good analysis of dog and wolf genome has happened.

This spring, a study that examined 48,000 genetic markers within the genome of different populations of wolves, coyotes, and domestic dogs revealed that the so called Eastern wolf and red wolf are simply not valid species. This was the most in depth analysis of the genetic material of any wild species and unlike the previous studies, included a broad sample of the genome.

They wolves of Algonquin Park are fairly close to 50/50 wolf and coyote hybrids, averaging 58 percent wolf and the rest coyote. The red wolf was found to be almost entirely coyote. On average, it was found to be 76 percent coyote and only 24 percent wolf.

It was also revealed that most Eastern coyotes have both wolf and dog ancestry, and it is from wolves that Eastern coyotes have inherited several wolf-like characteristics and adaptations. They have larger size and more powerful jaws than their Western counterparts, which makes preying upon deer much easier.

The so-called red wolf has only slightly more wolf ancestry than many Eastern coyotes, so it makes very little sense to go on and on about it.

But even if these studies have cast real doubt on the validity of the red wolf and Eastern wolf as valid species, they have revealed something else.

In North America, wolves and coyotes don’t merely exist as two potentially interbreeding yet clearly distinct species.

They actually exist within what is called a species complex.

In a species complex, it is somewhat difficult to determine where one species begins and another ends. The two species are exchanging genes, if not regularly then regularly enough to cause a great deal of blurring between the two. This hybridization also winds up affecting the evolution of both species.

The  so-called red wolf, the so-called Eastern wolf, and the Eastern coyote subspecies are examples of  how the gene flow between these two species wind up blurring the edges.

The species complex should called the Canis lupus/Canis latrans species complex.

Thus far, it is the only one that has been discovered within large terrestrial carnivores, but one likely existed between polar and brown/grizzly bears. One may exist between bobcats and Canada lynx, and one existed between modern humans and Neanderthals– and perhaps the Denisovan hominins, if they actually existed.

Golden jackals might have something similar going on in the Old World. Golden jackals are widespread animals, and they can hybridize with the Canis lupus species. Wild jackal-dog hybrids have been spotted– almost always the result of a male dog mating with a female jackal. Because they are raised by the wild parent, the pups will imprint upon the golden jackal, and if they survive to reproduce, they will likely contribute to the golden jackal population. In this way, dogs could have contributed genes to the golden jackal in the same way that dogs and wolves have contributed genes to coyotes.

I know of no examples of wild wolves interbreeding with golden jackals. However, there was canid that was thought of as a subspecies of golden jackal living in East and North Africa, but analysis of its mtDNA revealed it was actually a wolf. Nuclear DNA studies need to be performed to see exactly what it is, but in its mtDNA, it was found to be similar to the Indian and Himalayan wolf subspecies, which both possess the most ancient of modern wolf lineages. This “African wolf” (Canis lupus lupaster) is often quite small, so it could interbreed with golden jackals. In fact, I had initially thought the Egyptian population of these wolves, which had initially been believed to be the only wolf in Africa, was the result of hybridization with a relict North African population of Arabian wolves and the golden jackal. In dog and golden jackal hybrids, the father is usually the dog. In a wolf/golden jackal hybrid, the parentage is probably similar.  If the African wolf were a hybrid in the same way the red wolf is, the mtDNA– which is inherited maternally– would be unequivocally be that of the golden jackal, not some form of wolf.

The golden jackal has not been examined in the same way that the coyote, wolf, and dog have been. The African wolf subspecies has also not been examined in this depth.

It is possible if these animals were included in these studies that it might reveal a Canis lupus/Canis latrans/Canis aureus species complex.

Even though species complexes exist, the species in them are still distinct.

They are just less distinct than the differences between a wolf and an Ethiopian wolf and even less distinct than the differences between a wolf and a red fox.

The edges between wolves and coyotes are blurred through their interfertility.

Amazing, eh?

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