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Posts Tagged ‘Algonquin park wolf’

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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Long-time readers of this blog know that I have long been skeptical of the classification of the red wolf as a distinct species.

Because this animal is rather large and hunts in packs and because it closely resembles the primitive pallipes wolf of the Middle East and India, I guessed that it was an early offshoot of the Canis lupus species.  I never bought into the oft-promoted theory that this wolf was a primitive wolf that represented an even more ancient origin that the Canis mosbachensis and Canis lupus lineage of the Old World.

This theory, promoted by Ron Nowak and popularized throughout the wildlife conservation world (including the US Fish and Wildlife Service), holds that the red wolf is a derivative of Canis edwardii, an early North American member of the genus Canis that was roughly similar to the red wolf in size and general distribution. Nowak performed any number of skull measurements to prove his thesis. Anyone familiar with dog and wolf anatomy knows are actually among the most variable features within a population. Everyone has seen litters of dogs in which littermates have  different head shapes. Even in purebred litters, one can see puppies that have quite a bit of variance in head-type. For this reason, many conformation breeders of so-called “head breeds” have a very hard time fixing a consistent head within their lines. This variance in head shape also occurs in wolves, which is one reason why the Goyet cave  “dog” is so disputed. Is its short muzzle the result of domestication or natural variance within a wolf population?

Another factor drove me to question the red wolf’s validity as a species. I greatly enjoyed Bruce Hampton’s The Great American Wolf, which is a history of man’s extermination of wolves on this continent. On page 166, Hampton provides an image of red wolf that was trapped in 1929 at Gillham, Arkansas. The wolf’s jaws were bound with wire. It was then tied up to a stake to meet its fate. Either the dogs were going to be set upon it, or it was going to be left tied up to die from dehydration. Unfortunately, this image is not available in the preview, but what struck me about it is that this wolf looked nothing like the creatures that are claimed to be red wolves now. The animal had smaller ears and a broader muzzle– much like one would expect in an Iranian wolf or Spanish wolf. It was nothing like a coyote.

The ones I’ve seen in zoos have all had very strong coyote features– large ears and a narrower muzzle– but those same features can also been seen in Indian wolves, which are thought to be among the most ancient of extant wolf lineages.  Although I had skepticism about the Canis edwardii theory, I was more willing to accept that the red wolf was somehow related to the Indian wolf, for both would be very similar to the old primitive Canis lupus wolves from which the entire Holarctic wolf species descends.

The original mtDNA studies performed by Dr.Robert Wayne of UCLA found that all the red wolves in his samples had coyote or “gray wolf” mtDNA sequences. The majority of had coyote mtDNA.  The wolves of Minnesota and Quebec also had coyote mtDNA, which Wayne contended came from hybridization with coyotes. This finding caused an uproar in wolf conservation circles. This particular finding came out just seven years after the first red wolves were released into the Alligator River National Wildlife Refuge in North Carolina. The US Fish and Wildlife Service was investing heavily in ensuring that his population thrived and remained free from the taint of coyote blood. Even now, much the work in red wolf conservation is trapping coyotes in red wolf range. For some reason,  the released red wolves and the colonizing coyotes just loved each other.

Wayne was not popular in the red wolf conservation community. Nowak wrote a rebuttal to Wayne in which his biggest argument is that there never were any coyotes in the eastern part of North America. Then Wilson released several comparative studies of red wolves and those of Algonquin Park in Ontario. These Algonquin Park wolves were main study population of John and Mary Theberge.  These were smaller, more “coyote-like” wolves, that had come to specialize on hunting beavers in their native range. Because of their appearance and because they were thought to have coyote mtDNA, Paul Wilson’s team decided to compare microsatellites in the DNA of Algonquin wolves, red wolves, coyotes, and Western “gray” wolves. The Algonquin and red wolves were found to have a divergent lineage from either Western “gray” wolves and coyotes. Those findings appeared to vindicate Nowak’s morphological studies that showed the red wolf to be part of an ancient North American lineage of wolf that derived from Canis edwardii (or something wholly North American), not Canis mosbachensis or Canis lupus.

I thought the microsatellite finding was still unconvincing. Perhaps these wolves were derived from a very early offshoot of Canis mosbachensis or early Canis lupus that invaded North America before the main Holarctic wolf lineages had developed.

I was waiting for something more.

Well, something more has just been released. Robert Wayne’s team at UCLA has been working on wolf genomes. Last year, UCLA researchers found that the Middle Eastern wolf populations were a greater source for diversity in domestic dog genes than any other wolf population– which suggested that dogs were first domesticated in the Middle East. This finding very strongly contradicted a comparison of many, many dog and wolf mtDNA sequences by Peter Savolainen of the Royal Institute of Technology at Stockholm, Sweden, which found that dogs were first domesticated in East Asia. Greater diversity of lineages was found in that region, and it is accepted that one generally finds more diversity in mtDNA lineages at the point of origin. (This is how we figured out that modern humans first evolved in East Africa).

The UCLA study that contradicted Savolainen’s findings used a very sophisticated analysis technique to compare different parts of the genome. Using what are called SNP chips (“snip chips”) researchers are able to look at many different parts of the genome rather easily. This study used 48,000 different SNP chips, which is actually a far more in depth analysis than comparing the diversity of mtDNA lineages to determine heritage.  Mitochondrial DNA is inherited only through the mother, and although it is quite resistant to mutation, using it for analysis does have its limitation. Wayne’s original studies on the red wolf used only mtDNA sequences, which is one reason why the microsatellite data could still suggest that red wolves were an ancient North American species.

Well, on May 12, UCLA released the findings of a similar genome-wide study on wolves from Eurasia and North America, red wolves, coyotes and domestic dogs.   It used roughly 48,000 SNP chips to examine 48,000 loci in the genomes of these creatures.

This is where red wolves fit:

Red wolves are genetically coyotes. Like many populations of coyote, these coyotes do have some wolf ancestry. In fact, many coyotes have both wolf and dog ancestry, with only the Western population remaining “pure.”

This study also found that coyotes likely lived in the Eastern parts of North America at varying times. There are wolves with definite coyote mtDNA that predate Columbus that have been found in places like New York and Quebec. Indeed, the researchers final conclusion is that there was a massive “hybrid zone” between wolves and coyotes in North America– the largest hybrid zone ever documented in a terrestrial vertebrate species. For millennia, wolves and coyotes have exchanged genes– as have dogs and wolves and dogs and coyotes.

The Great Lakes wolves, which were said to be the same species as the red wolf, were found to have quite a bit of coyote ancestry, but it was nowhere near as much as the red wolf.  The Algonquin wolf was about 40 percent coyote, which was the highest concentration coyote ancestry in the Great Lakes wolf population, while the red wolf was 75-80 percent coyote and only 25-20 percent wolf. That is just a bit higher wolf ancestry than many coyote populations. One might actually call the Algonquin wolf a “stable hybrid,” but it may have coyote ancestry that traces back before Columbus. Which means it is a subspecies of Canis lupus with coyote ancestry with a unique ecological niche– which means that one could argue for its continued preservation.

Not so with with the red wolf.

This study strongly suggests that the red wolf is not a distinct species at all. In fact, it’s probably  not even a member of a species that is endangered anywhere.

That finding is not going to go over very well at all. I have noticed that this study has not been widely publicized in the media.

I think it is possible that there was a southeastern wolf population that was closely related to the Great Lakes wolf subspecies. This animal became extinct and was absorbed into the growing coyote population. Perhaps this southeastern wolf already had some coyote ancestry from many generations before, but as it disappeared, it was forced to mate with coyotes to survive. It exists now only as that 20-25% heritage that is in so-called “red wolf.”

It is very likely that the red wolf as it exists now simply came from a population admixed coyotes with wolf ancestry in Texas and Louisiana. Some of these mixed coyotes retained some wolf features. These coyotes with wolf features were the ones that were trapped, deemed an endangered species, and then were released into Eastern North Carolina, where the US Fish and Wildlife service has tried to keep this breed pure under the assumption that it is a species of rare wolf from an ancient North American lineage.

As for the pack hunting aspect of this “red wolf,” coyotes can learn to form packs and evolve larger size, even if they have only traces of wolf ancestry. That is certainly the case with the Eastern coyote, which is now evolving into a kind of wolf-coyote that hunts deer. And that would explain why red wolves would form packs and hunt deer and raccoons in North Carolina. Pack-hunting is not exclusively the purview of wolves. Coyotes can do it, too.

This study is the most advanced analysis of the red wolf’s genetics that has yet been performed.  These results have not trickled down into the popular conscience yet.

But once they do, it is going to be very hard to argue for the continued preservation of the red wolf in Eastern North Carolina or anywhere else it has been released. A big coyote with wolf ancestry that hunts deer is not an endangered species at all. We have them in West Virginia, but no one would call them an endangered species or some ancient wolf lineage. People want bounties on that coyote here.

But the US Fish and Wildlife Service and many, many scientists have put countless hours into red wolf. Lots of  money has been spent.

How are these new facts going to be received?

It is no longer the red wolf.  It is the creature formerly known as the red wolf.

That finding is an affront to the conscience of so many people.

And I don’t know how we can justify preserving this form of deer-hunting coyote when we already have another much more healthy population of deer-hunting coyote that continues to establish itself in the East.

These questions have yet to be answered.

But the debate surely will start soon. The US federal government is looking for programs to cut, and funding for red wolf reintroduction and management looks like its been dealt a pretty crushing blow.

I don’t see any how any other genetic studies can cast doubt onto what UCLA’s researchers have found.

Oh well.

There are plenty of other more worthy endangered species– including the Mexican wolf subspecies and the Island fox– that need some attention. Perhaps these animals could benefit from some of the funding and man-hours that have been allocated to red wolves.

That is one positive for which we can all hope.

The truth is not going to be received, but at least it’s the truth.

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H/T to Dave at Little Heelers for passing this onto me. He had me look at it for what it said about the genetics of Italian and Spanish wolves (for some reason). But the findings on the red wolf were a much bigger deal!

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Update: To be fair, Nowak did eventually drop the Canis edwardii theory in 2002 and adopted the mosbachensis theory, which is very similar to what I thought these wolves were.

However, we were both wrong in assuming that modern red wolves were either derivatives of edwardii or mosbachensis. The only mosbachensis in the red wolf is the 20-25 percent of “gray wolf” in its ancestry. Some authorities count the mosbachensis wolf as Canis lupus mosbachensis, an extinct early subspecies of the “gray wolf.”

Edwardii was likely an early wolf-like coyote or wolf-like Canis related to the coyote.

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