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Posts Tagged ‘Eastern wolf’

I’m so glad these taxonomy issues are being raised on a popular science Youtube series:

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west virginia coyote

I’m currently reading John Lane’s excellent book, Coyote Settles the SouthIt is an excellent book, and I will be reviewing it here very soon. The whole time I’ve been reading it I thinking about my encounter with the male Eastern coyote I called in back in March.

He’s not exactly the same coyote that Lane is writing about. He’s a coyote of the gray woods, not the subtropical pine forests and river bottoms.

But in some ways, he is the same. He is the same creature that has adjusted to all that Western man can throw at him and thrived.

And he’s thrived at the expense of the wolves that once roamed over the Northeastern US and the South. He’s just the right size to live on a diet of rodents and rabbits but also has the ability to pack up and hunt deer. He can be an omnivore, enjoying wild apples and pears that fall to the ground, almost as much as he would if he came across a winter-killed deer.

The coyote is a survivor. I’ve written on this space several times that the reason he has thrived is because he has been here far longer than the wolves that once harried his kind. Until last week, it was assumed that the coyote split from the wolf some 1 million years ago. This million year split has been used for virtually every study that has examined the relationships between different populations or species in the genus Canis. It is used to set the molecular clock so that we can figure out when wolves and dogs split and perhaps give us some idea as to when dogs may have been domesticated.

This assumption has been directly challenged in a new study that was released in Science Advances last week. The paper examined full genome sequences of several different canids, and it can be argued that it pretty much ended the debate as to whether the red wolf and Eastern wolf are species. They aren’t. Instead, they are the result of hybridization between wolves and coyotes. Most of the media attention has paid attention to this discovery in the study.

It’s the most important practical implications, because the US Fish and Wildlife Service delisted the gray or Holarctic wolf in most of the Eastern, Southern, and Midwestern states in favor of protecting the Eastern and red wolves. Red wolves are called Canis rufus, and  Eastern wolf is Canis lycaon. With them being recognized as hybrids, this greatly complicates the issue of how to conserve them under the Endangered Species Act, which, as its name suggests, is meant to conserve actual species and not hybrids between species.

The authors of the study feel that these hybrid populations are still worth conserving, largely because the red wolf contains the last reservoir of genes belonging to the now extinct wolves of the Southeast.

But in order to make this work, we’re probably going to have to rewrite the Endangered Species Act, and that is not going to happen any time soon.

However, the finding in the study that is worth discussing more is that not only showed that red and Eastern wolves were not some relict ancient species of wolf. It is the finding that coyotes and wolves split only 50,000 years ago.

Using a simple isolation model and a summary likelihood approach, we estimated a Eurasian gray wolf–coyote divergence time of T = 0.38 N generations (95% confidence interval, 0.376 to 0.386 N), where N is the effective population size. If we assume a generation time of 3 years, and an effective population size of 45,000 (24, 25), then this corresponds to a divergence time of 50.8 to 52.1 thousand years ago (ka), roughly the same as previous estimates of the divergence time of extant gray wolves.

This finding means that the studies that use that 1 million year divergence time to set the molecular clock for all those dog domestication studies need to be reworked. This is going to have some effect on how we think about dog domestication, and although the domestication dates have been moved back in recent years, the actual split between dogs and wolves is likely to be much later than when we see the first signs of domestication in subfossil canids.

That’s one important finding that comes from this discovery that wolves and coyotes are much more closely related.

The other is that yes, it did pretty much end Canis rufus and Canis lycaon as actual species, but it probably also ends the validity of Canis latrans as a valid species. Coyotes could be classified as a subspecies of wolf. Indeed, they are much more closely related to wolves than Old World red foxes are to New World red foxes, which split 4oo,ooo years ago. And there is still some debate as to whether these two foxes are distinct species, because we’ve traditionally classified them as a single species. Plus, if we start splitting them into two species, we’re likely to find the same thing exists with least weasels living in the Old and New World. And the same thing with stoats.

And then it’s not long we’re fighting over the house mouse species complex.

But if we’re going to lump red foxes, it’s pretty hard not to lump coyotes and wolves. It is true that wolves normally kill coyotes in their territory, but it also found that wolves in Alsaska and Yellowstone, wolves that were thought to be entirely free of any New World ancestry, also had some coyote genes.

So the coyote, like the extinct Honshu wolf and the current Arabian wolf, could be correctly thought of a small subspecies of wolf. We know from paleontology that in both North America and Eurasia there were various forms of canid that varied from jackal-like to wolf-like, and although we know the jackal-like form is the earliest form, these two types have ebbed and flowed across Eurasia and North America. We’ve assumed that the jackal-like forms gave became the coyote and the larger wolf-like forms have become the gray, red, and dire wolves.

But what we’re looking at now is the coyote isn’t the ancient species we thought it was. It’s very likely that some ancestral wolf population came into North America, and instead assuming the pack-hunting behavior of Eurasian wolves, it tended toward the behavior of a golden jackal. When this ancient wolf walked into North America, it would have found that the pack-hunting niche was already occupied by dire wolves. There were many other large predators around as well, and evolving to the jackal-like niche would have made a lot more sense in evolutionary terms.

This is what the coyote is.

The pack-hunting modern wolf came into the continent and took it by storm, and the coyote exchanged genes with it. They lived together as sort of species-like populations in the West, but when wolves became rare from persecution following European settlement, the coyote and wolf began to exchange genes much more.

So with one study using complete genomes, the entire taxonomy of North American Canis is truly blown asunder.

And the implications for dog domestication studies and for the practical application of the Endangered Species Act could not be any more consequential.

Very rarely do you get studies like this one.

It changes so much, and the question about what a coyote is has become unusually unsettling but also oddly amazing.

I will never think of a coyote the same way.

The mystery is even more mysterious.

 

 

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Supposedly, wolves and coyotes always hate each other.

And even though they can crossbreed and produce fertile offspring, we know that they never have in the wild.

So goes the reasoning behind the denialism that certain wolves in the Eastern Canada are wolves with some coyote ancestry.

But California’s sole wolf, which wandered down from Oregon last winter, seems to have not read all books.

He was recently spotted playing with some coyotes!

It’s very likely that relic wolf population in the East and Midwestern US– and yes, the South– were very willing to interbreed with coyotes as they gradually worked their way across the continent. There may have always been some small populations of coyote in the East, and these coyotes hooked up with the relict populations of wolf.

Wolves and coyotes likely only cross when wolf populations are heavily pressed. The two animals have very different body language, and normally, wolves kill whatever coyotes they encounter.

But this wolf is showing us what it may have been like for those remaining few wolves in the East as they encountered a swelling tide of coyotes.

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It has been nearly a year since the paradigm-shattering study on the wolf and coyote genomes was released. (vonHolt 2011). The study examined 48,000 SNP’s (single-nucleotide polymorphism) in the genomes of these species and compared them to each other. In this way, the researchers were able to see which animals were most closely related to each other.

The study was the most in-depth analysis of a wild species’ genome that had ever been performed, and it revealed that several sacred cows in wolf taxonomy are not what they have been proposed to be.

The so-called “Eastern wolf,” which lives in Quebec and Ontario, has been proposed to be a unique species.  Mitochondrial DNA analysis  suggested so, as did some limited microsatelite analysis.

The same was found for the red wolf of the southeastern US.

Most of these studies were designed to counter Robert Wayne’s study that revealed that all red wolves actually had coyote mtDNA. He initially contended that they were hybrids between wolves and coyotes, but red wolves were still worthy of conservation because a large number of wolves had coyote mtDNA sequeneces. Wayne also found at least one red wolf with wolf mtDNA sequence, which really raised a red flag. Although most red wolves were found to have coyote mtDNA, finding one with wolf mtDNA was really indicative of these animals being of hybrid origin.

Of course, this drove some people really crazy. Ron Nowak, a comparative anatomist who worked for the US Fish and Wildlife Service, tried several times to connect the red wolf to any number of prehistoric wolf-like canids that existed in North America, as well as claiming that the reason why these animals appeared to have coyote mtDNA is because they, as native North American Canis, would be more closely related to the coyote. It would not necessarily be indicative of hybridization.

Mitochondrial DNA is inherited only maternally, and we do know that when wolves and coyotes mate in the wild, the hybrid is almost always a male wolf mating with a female coyote.

So we have this problem of certain animals that are called wolves that have coyote mtDNA.

And there were three potential hypotheses:

  1. These wolves represent an ancient species that evolved from the same ancestor as the coyote.
  2. These wolves are the same species as other wolves. They just have coyote mtDNA from a coyote that entered the gene pool in recent times.
  3. These wolves are a unique species that resulted from an ancient hybridization between wolves and coyotes.

I generally came to accept a sort of hybrid between 2 and 3. I thought that red wolves and Eastern wolves were the result of an old introgression of coyote genes into the wolf population. When the first wolves came across the Bering Land Bridge, they likely didn’t come in large numbers and as they came down into the middle latitudes of North America, the only available mates would have been coyotes. They mated with  female coyotes and carried coyote mtDNA into Eastern North America.

However, the vonHolt SNP study changed all of this.

It essentially rendered all previous hypotheses and findings moot.

What this study found was the the wolves with coyote mtDNA, the red wolves and those of the Great Lakes and Eastern Canada, had SNP’s in common with Canis lupus and Canis latrans. Eastern coyotes also had wolf SNP’s.

And what’s more, all the hybridizations, except the one involving the Western Great Lakes wolves,  happened after colonization. The Western Great Lakes hybridization happened between 600 and 900 years ago, but these wolves are only 15 percent coyote on average. Thus, after that initial cross, they have been breeding back into wolves.

Red wolves were found to be almost entirely coyote, averaging 76 percent coyote and 24 percent wolf.  Algonquin Park wolves, which have been much ballyhooed in the Canadian wildlife literature, are pretty close to 50/50 wolf and coyote. They averaged 58 percent wolf and 42 percent coyote.

If these animals had been an ancient unique species, it would have come out in this analysis. Instead, this analysis found something more interesting. Wolves and coyotes are distinct species, but the edge between them is blurred a bit. Wolves and coyotes do exchange genes under certain circumstances. In this way, there is a sort of species complex between them.

But what about discoveries of pre-Columbian wolves with coyote mtDNA?

Rutledge found coyote mtDNA sequences in wolf-like canids that were living in Quebec 400-500 years ago.

But these hybrids were around centuries after the wolves of the Great Lakes received their coyote introgression. Perhaps these pre-Columbian wolves with coyote mtDNA were initially more widespread. The Great Lakes and Quebec are actually linked as a waterway and the terrain makes it very easy for animals to move from one side to the other.

The Great Lakes and into the St. Lawrence is a major pathway for Carnivorans. This is the path that coyotes used to enter the northeastern US all the way down to Virginia.

So these two species have  interbred at different times.

The Eastern wolf and the red wolf are merely the result of hybridization, and they do not represent ancient species that are independent from the main wolf or coyote lineage.

The same can be said for the Eastern coyote, which does have some wolf ancestry.

As for the ancient species that Nowak and other hitched their arguments to, a much more likely explanation is that the coyote and wolf lineages have produced animals that look more like wolves or more like coyotes.

The Arabian wolf is very much like a coyote. It doesn’t normally form large packs, and some individuals can be in the 25-pound range.

The Honshu wolf was even more similar to a coyote and was reported to have occasionally matured weighing in the 20 pound range.

And there is good evidence that coyotes during the Pleistocene were quite a bit larger than they are now.

It’s likely that ancient North American Canis had the same proclivities. Different conditions produced selection pressures for different sizes, and one could get wolf-sized animals out of the coyote lineage.

We’re seeing something similar going on with Eastern coyotes, which are evolving larger size and more powerful jaws in order to become better deer hunters. They get these traits from their wolf ancestors, but natural selection is also playing a role.

So one needs to be careful of someone trying to use the fossil record to argue against genome-wide studies.

The wolf conservation community has not accepted these findings. The US Fish and Wildlife Service just ignored the vonHolt study entirely.

David Mech, an expert on wolf ecology and behavior, said it couldn’t be true because he’d never seen a wolf and coyote mate in the wild– as if that somehow contradicted the DNA evidence that they have and continue to do so!

The paradigm says that the red wolf is the second wolf species. It is an ancient North America species that ranged all over the Eastern part of the continent.

Too bad the evidence for this entirely exists in rather superficial DNA analyses and the speculations of paleontologists.

The DNA simply says otherwise.

And the red wolf and the Eastern wolf are fictional animals, the result of overly imaginative hypotheses and not enough hard science.

Just because a fossil looks like an animal alive today doesn’t mean that it is the ancestor of the extant form.

Making inferences from fossils will always be haphazard and speculative to a certain point, and sometimes, the DNA evidence totally contradicts and falsifies these inferences.

That’s what happened here.

Too bad it’s not being recognized in an official capacity.

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Jacques Mallet killed what he thought was a giant coyote at Saint Simon on New Brunswick's Acadian Peninsula. Because it weighed 86 pounds, it would have been the largest coyote on record, but everyone, including Mallet, thinks this animal is a wolf. DNA tests have been ordered to see exactly what it is.

The initial report from the CBC found that Jacques Mallet was getting ready to kill his second coyote. He had been hunting the robust, deer hunting Eastern coyotes of the New Brunswick for two years now.   He’d killed one last year, and now, he was stalking Canis latrans— “the barking dog”– at St. Simon on the Acadian Peninsula.

The story that follows starts out routine but soon becomes a bit screwy:

He saw a big one, fired, dropped it, but when he came upon his kill, he was shocked at what lay before him.

The great gray canid that lay before him was massive– much larger than any coyote ever seen in these parts or anywhere else.

The CBC reports Mallet is almost certain that this animal is a wolf:

“I said, ‘Oh my God, maybe that’s not a coyote. That’s a wolf. I don’t know what it is.’ I was quite surprised.”

Wolves are officially extinct in the province. They officially disappeared in 1876, so if this animals is determined to be a wolf, then Mallet will have to give it up to the provincial wildlife authorities.

However, one should keep in mind that virtually all coyotes in Eastern North America are part wolf, and virtually all wolves in Eastern Canada have coyote mtDNA, which has led to some foolish assertions about these animals– most specifically that they represent a unique “Eastern wolf” species.

So I hope they aren’t just doing an mtDNA test.

That is almost guaranteed to result in this animal being declared a coyote.

Y-chromosome and microsatellite analyses are going to be needed to determine this animal’s identity.

But wolves are coming back in Eastern Canada and in Northern New England.  Reintroductions are not necessary.

They are going to come on their own volition.

And that’s the best way.

If wolves come into a region, they are going to know from their experiences on the way what the proper behavior is and how to avoid humans.

Wolves can be an in area and cause very few problems, as we’ve seen with Germany’s wolves.

But if they are introduced, there will always be attacks on whether one has introduced the wrong subspecies and these wolves may or may not know how to behave in a new environment. And they might start killing stock.

I’m only in favor of wolf reintroduction if it is absolutely impossible for wolves to get to a region on their own.

Mexican wolves were extinct in the wild until relatively recently, so they had to be reintroduced.

This wolf in New Brunswick suggests that wolves are more than capable of recolonizing the East on their own.

And I really don’t see what’s wrong with that.

Even if these wolves do occasionally bred with coyotes in the wild, this hybridization occurred in the past, even before European colonization. The wolves of the Western Great Lakes have an introgression of coyote genes that was estimated to have happened between 600 and 900 years ago.

Nature has created a species complex between wolves and coyotes in North America.

It’s just very hard for people to see that there is not hard edge separating these two species.

It’s muddled.

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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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From Art Daily:

A State Museum scientist has co-authored a new research article, representing the most detailed genomic study of its kind, which shows that wolves and coyotes in the eastern United States are hybrids between gray wolves, coyotes and domestic dogs.

Dr. Roland Kays, the Museum’s curator of mammals, was one of 15 other national and international scientists who collaborated on the study that used unprecedented genetic technology, developed from the dog genome, to survey the global genetic diversity in dogs, wolves and coyotes. The study used over 48,000 genetic markers, making it the most detailed genomic study of any wild vertebrate species.

The research results are especially relevant to wolves and coyotes in the Northeast. The study shows a gradient of hybridization in wolves, with pure wolves in western states and increasing hybridization as you move east. Wolves in the western Great Lakes area averaged a genetic makeup of 85 percent wolf and 15 percent coyote, while wolves in Algonquin Park in eastern Ontario averaged 58 percent wolf, and the ‘red wolf’ in North Carolina was only 24 percent wolf and 76 percent coyote. Populations of eastern coyotes, which only colonized the region in the last 60 years, were also minor hybrids, with some introgression of genetic material from wolves and domestic dogs. For example, Northeastern coyotes, including those in New York State, had genetic material primarily from coyotes (82 percent), with a minor contribution from dogs (9 percent) and wolves (9 percent). Midwestern and southeastern coyotes were genetically 90 percent coyote, with an average of 7.5 percent dog and 2.5 percent wolf.

The advanced genetic techniques used in this study also allowed the scientists to estimate when the hybridization initially occurred. Kays said “In most cases this breeding across species lines seems to have happened at times when humans were hunting eastern wolves to extinction, and the few remaining animals could find no proper mates, so took the best option they could get.” Kays continues, “The exceptions were an older hybridization between coyotes and wolves in the western Great Lakes dating from 600-900 years ago, and a coyote-dog hybridization in the eastern U.S. about 50 years ago, when coyote were first colonizing eastern forests.”

This study also provides fresh data on the controversy over the species status of the Red Wolf in North Carolina, and the Eastern Canadian Wolf in Ontario. Both are medium-sized wolves that some have argued represent unique species. However, this new detailed genetic data shows both are the result of hybridizations between coyotes and wolves over the last few hundred years, and do not share a common origin in a unique eastern wolf species.

This research is also relevant to a recent U.S. Fish and Wildlife proposal to remove the western Great Lakes wolves from the Endangered Species Act by showing that those wolves are only marginally hybridized with coyotes, should be considered a subspecies of the Gray Wolf, and have no genetic ties to a more endangered form of eastern wolf.

The research is published online in Genome Research, an international, peer-reviewed journal that publishes outstanding original research that provides novel insights into the genome biology of all organisms, including advances in genomic medicine.

This study follows another research paper co-authored by Kays last year in the journal Biology Letters, which used museum specimens and genetic samples to show that eastern coyotes hybridized with wolves to rapidly evolve into a larger form over the last 90 years, dramatically expanding their geographic range and becoming the top predator in the Northeast. This hybridization contributed to the evolution of coyotes from mousers of western grasslands to deer hunters of eastern forests. The resulting coy-wolf hybrids are larger, with wider skulls that are better adapted for hunting deer.

You’ve seen some analysis from this study already. I already posted on the same study, paying close attention to the red wolf findings.

The unique Eastern wolf hypothesis has been popularized through the past decade.  If one looks at the various maps of different wolf “species,”  the region of the country in which I live could have had three possible wolves– red wolves, gray wolves, and “Eastern wolves.” It currently has coyotes with some wolf and dog ancestry.

This study shows that there was some Pre-Columbian hybridization between wolves and coyotes. Why this hybridization occurred is not clear– other than 600-900,  there were coyotes or coyote-type animals living near wolves in the Great Lakes region.

This hybridization also happened only in the Southeastern and Eastern populations of wolf. The Western, Northern, and Mexican wolf populations are free of coyote  blood.  Why the Mexican and Western wolves don’t have coyote ancestry isn’t entirely clear either. Western wolves are generally larger animals that are derived from the “moose-killer’ type of wolf that was among the last types to colonize North America from Eurasia.  The coyotes of the West are quite small and probably aren’t suitable mates for such large wolves. These large wolves also kill coyote and often eat them if they happen to share the same range. The wolves of Eastern North America are smaller and likely represent an earlier colonization. Although larger than coyotes, they would have an easier time breeding with them. But Mexican wolves are also smaller, but the only evidence of coyote and Mexican wolf hybridization has been found in coyotes, such as this “chupacabra,” which had some Mexican wolf ancestry on its father’s side.

It looks like the Eastern wolf hypothesis, which I always thought was touchy, is probably not correct at all.

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