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coyote pupps.jpg

I have a lot of quibbles with Dan Flores’s book, Coyote America. Among them is a contention that coyotes howl because it allows them to “take a census.”  If no other coyotes howl back, the females wind up releasing more ova and having larger litters. This description, which Flores calls an “autogenic trait,” cannot be found anywhere in the coyote literature. His account is not described in the book, but it is mentioned in his interview with National Geographic and on The Joe Rogan Experience.

I have no idea where Flores got this idea, but it’s not really what happens. The literature on why coyotes have larger litters in areas where they have been heavily hunted says that the larger litter sizes are associated with better access to food resources. The best-known paper on this issue comes from Eric Gese, a researcher with the USDA, who studied coyote population dynamics in an area of Colorado.

Gese contends that what happens with coyotes in pressured areas is that the surviving females are healthier, simply because they have access to more food resources. This greater health causes them to release more ova during the estrus cycle, and this increase in ova results in greater litter sizes.

It is not because the coyotes are taking census and can somehow magically figure out that they should produce more young.  It is simply that the coyote females’ own bodies respond to greater food resources by becoming more fertile.

What has possibly evolved in coyotes is that they have a tendency to become significantly more fertile when the females are at their most healthy. This is a great trait for a mesopredator to have.

After all, coyotes evolved in North America with dire wolves and a host of large cats breathing down their necks. Natural selection favored those that could reproduce quickly if populations were dropped dramatically.

But it’s not because of some “autogenic trait.” It is simply how coyote populations expand as mesopredators with increased or decreased access to prey.

So yeah, my take on Coyote America is that it is mostly a science fiction book. Not only does he mess up the exact genetic difference between a wolf and a coyote, which is not equivalent to the genetic difference between a human and an orangutan (as he claims),  he also messes up that coyotes really do hunt down and kill cats and eat them. They are not just killing a competitor. They are using cats as a food resource.

This was a book I was so looking forward to reading. It got good press, but the actual science in it was so lacking.

 

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Epic Wolf Encounter

What happens when you catch a wolf out mousing in Montana:

 

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northwestern wolf

A lot of attention is being paid to the initiative that will be on the Colorado ballot this year. The question is whether the state will reintroduce wolves to Colorado, and various interests are queuing up for a rancorous debate about whether the state should begin this process.

The neighboring state of Wyoming, though, has a decent wolf population, and one argument against the reintroduction measure is that the wolves will do the reintroduction on their own. They will simply walk down from Wyoming and enter Colorado on their own.

Well, yesterday, there was news that wolf tracks were spotted in the snow in the northwestern corner of Colorado. There have also been sightings. An elk carcass has also been found, and wolf howls have been heard. So it is very likely that some wolves are now roaming Colorado, and they may be establishing a pack.

However, this does not change the debate on the ballot question, because if it is passed, these wolves will likely be joined by others.

And, it makes something else more interesting. The ballot question is about gray wolves, but there were historically two subspecies of gray wolf that roamed Colorado.

The ones in Wyoming are Northwestern wolves, but Colorado was also the northern terminus for the Mexican gray wolf’s range. If this ballot question is approved, then a real discussion should be had about restoring Mexican gray wolves to parts of southwestern Colorado.

A huge debate exists about the wolf subspecies of North America, not just with the potentially coyote introgressed “species.”  A real debate exists about whether the Northwestern wolf is the same as the Southern Rocky Mountain wolf, which was also a fairly large wolf.  This also where you get these big debates about giant Canadian wolves with the anti-wolf opposition in much of the West.

What would happen is that you probably would have a gene flow between Northwestern wolves and Mexican gray wolves, and natural selection would favor those that had the adaptations to handle the local prey.

But this probably would cause lots of issues, because Mexican gray wolves are seen as such a unique subspecies that a whole line of them was euthanized for merely showing some dog-like characteristics.

So wolf taxonomy is always an issue with recovery, even if you leave out the domestic dog and coyote introgressions.

 

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Isle Royale’s new wolves

isle royal new wolf

The wolf reintroductions that began last year on Isle Royale are starting to bear fruit.. Reports are that two male wolves and a female are running together,and they are beginning to hunt moose calves, snowshoe hares, and beavers.

Further, it was reported today that one the last survivors of the original Isle Royale wolf population was killed in a scuffle with the new wolves.  This male wolf from the original population could be the last survivor, because the other remaining wolf is a ten-year-old female that has never been radio-collared or studied. She could very well be dead by now, but researchers are trying to figure out her whereabouts.

Wolves and moose were not the original predator-prey dynamic of the island.  The original dynamic involved woodland caribou, which became extirpated, and Canada lynx, which became extirpated in the 1930s, and coyotes, which became extirpated shortly after wolves arrived.

The first wolves crossed an ice bridge from the Ontario mainland and colonized the island in 1949. The moose showed up in the early 1900s and came either by swimming or through human stocking.

The original wolves of Isle Royale were a unsustainable population. The ice bridges stopped forming every year to connect the island to the Minnesota and Ontario mainlands, and new genetic material never had a chance to work its way into the population. One wolf, Old Gray Guy, did manage to walk over into the island in 1997, and he did offer some genetic rescue. However, his genes wound up swamping the population, making inbreeding issues worse.

This island, which never was known for having wolves or moose, is now a sort of experiment that is going to be managed through human interference. Every few decades,  wolves will have to be released on the island, just to maintain the population’s genetic diversity.

Isle Royale now exists somewhere between a zoo and a wildlife preserve.  Wolves must be maintained through constant human interference. Moose are controlled by wolf predation. Moose control the growth of trees on the island, and by continuously introducing wolves, the ecosystem is managed.

This is not an attempt to restore an ecosystem to the time of yore, before man began industrial level exploitation of the forests on the island. If it were, then the National Park Service would open up a moose season on the island with hopes of eventually extirpating them. It would restore caribou and turn loose a bunch of Canada lynx and coyotes.

But so much research and public awareness of the island comes from its studies of wolf and moose dynamics that it will be maintained as a wolf and moose park. In this way, it is an artificial wilderness.

But no place affords such easy access to wolf and moose predator-prey population dynamics, so it will be restored to the state it was in the 1950s.  It is an amazing place, and the research tells us so much.

But it is not being left to nature. And it is not a restoration of the original condition. It is an aesthetic that exists beyond our usual concepts of wilderness. We have a place where wolves can hunt moose, and scientists can study them with relative ease.

And that practicality trumps Gaia and probably will every time.

 

 

 

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galante and wolf

Forrest Galante hanging out with a socialized wolf that has features similar to the Southern Rocky Mountains gray wolf.

As long-time readers of this blog know, I am a huge fan of Forrest Galante’s Extinct or Alive on Animal Planet.  In the new season, he documents the discovery of the Fernandina tortoise, a Galapagos giant tortoise that has been declared extinct in the wild.  He also has found an unusual giant lion in Zimbabwe that has genetics that cannot be described to any known form of lion in Zimbabwe and might be descended from the massive Cape lion of South Africa.

So yeah, I love this show. The most recent episode involved looking for the Southern Rockies gray wolf in the Sierras of California. Some canid had been killing cattle in that part of the world, and when Galante’s team went into the region looking for the animal, they found lots of interesting things. With use of a German shepherd tracking dog, he discovers a massive deer that has been killed by a canid, and later investigations revealed a large canid that left massive tracks in the snow.

He finally captured the animal on trail camera, and he initially thought it was a wolf. But it had too many coyote-like features to suggest that it was pure.  So Galante surmised that this animal was a coywolf.

Now, this raises a lot of questions. One is that no one has ever seen a coyote-wolf cross in the West before. We know that they exist or existed because the genomes of Western wolves suggest some tiny amounts of coyote ancestry. But no one has seen one before in the West.

Further, the first wolf to enter California from Oregon was noted for his friendly relationship with coyotes. This wolf was of the Northwestern wolf subspecies, but it is possible that he passed some genes into the coyote population.  In recent years, wolves have colonized and bred in California. One pack, called the Shasta Pack, mysteriously disappeared, either killed by poachers or just dispersed. It is possible that a survivor of this pack wandered south into the Sierras and bred with a coyote.

So Galante is finding lots of interesting things in the wild.  One thing I did sort of quibble with in the episode is idea that wolves and humans were at constant enmity in indigenous cultures. Yes, there was conflict between hunting man wolves on this continent, but the work of Raymond Pierotti and Brandy Fogg has revealed that many indigenous cultures had a close relationship with wolves, which often bordered on something like a pre-domestication symbiosis. He played up potential conflicts between indigenous people and wolves, but reality was a lot more nuanced than that.

Also, I don’t think most people are aware of the really upsetting discovery that gray wolves and coyotes last shared a common ancestor only around 50,000 years ago and that the two forms of canid have exchanged genes across the continent. That discovery has been sort of paradigm shattering for me. I have never looked at coyotes the same way since it came out.

Wolves and lions were once the most widespread large predators in the world. Depending upon which version of lion taxonomy one prefers, the American lion was either a subspecies of modern lion or a lineage of cave lions, which were a sister species to the modern lion.  If one considers it the former, then lions had a much larger range than gray wolves ever did, but if one considers it the latter, then gray wolves were the most widely distributed large predator.

It should be no surprise that lions and wolves have lots of mysteries lurking in their double helices.  Galante is getting the public to look at these animals with new eyes.  Lots of hidden things are there to be discovered.

More work need to be done to document Galante’s coywolf, but it is something that should be taken seriously.

 

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coyote wolf cross.PNG

An F1 cross between a gray wolf and a coyote that was produced through artificial insemination.

A few months ago, I wrote about a discovery that two species of howler monkey have evolved greater genetic divergence in a hybridization zone in southern Mexico. The hybrids were less fit to survive or reproduce, so natural selection has favored those individuals in both species that were genetically more divergent where their ranges overlap. This phenomenon, known as “reinforcement,” is a powerful tool that maintains both species as distinct.

I have been thinking about how this phenomenon may have played out in wolf evolution in North America.  We have found that gray wolves across North America have at least some amount of coyote introgression, which has been revealed in several full genome comparisons.

The wolves that have most evidence of coyote introgression are those that live in areas that were not in the historic range of coyotes, while those with the least coyote introgression tend to be in the areas where gray wolves and coyotes were sympatric.

It is possible that something like reinforcement went on with wolves and coyotes living in the West. Hybrids between gray wolves and coyotes were probably less likely to be able to bring down large prey or were too large to live on small game, which is the staple diet of most Western coyotes. Over time, reinforcement through natural selection could have caused greater genetic differences between Western wolves and coyotes, and Eastern wolves were without coyote and thus never developed these greater genetic differences.

When coyotes came into the East, they mated with relict wolves, so that we now have whole populations of wolf with significant coyote ancestry.

Now, this idea is not one that I find entirely convincing. One is that ancient mitochrondrial DNA analysis from wolves in the East suggests they had coyote-like MtDNA, which, of course, leads to the idea that the wolves of the East were a distinct species.

Further, the discovery of the recent origins of the coyote makes all of this much more murky.  Again, reinforcement is a process that is only just now being sussed out in the literature, and gray wolves and coyotes are unique in how much introgression exists between them.  Their hybridization has essentially been documented across a continent. The only wolves that have no evidence of coyote ancestry live on the Queen Elizabeth Islands of the Canadian arctic. No coyotes have ever lived on these islands, so they have never introgressed into the wolf population.

The howler monkeys in the reinforcement study hybridize only along a narrow zone in the Mexican state of Tabasco. They are also much more genetically distinct than wolves and coyotes are. The monkeys diverged 3 million years ago, but the current estimate of when gray wolves and coyotes shared a common ancestor is around 50,000 years ago.

So gray wolf and coyote “speciation” is a lot more complex than the issues surrounding these monkeys.

But reinforcement is something to think about, even if it doesn’t fit the paradigm exactly.

 

 

 

 

 

 

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panama coyote

The coyote has spread to almost the entirety of the North American continent. They are absent from much of the treeless tundra of the Canadian High Arctic, but they are at home in Alaska and Labrador. They range all through the United States and through all of Mexico. They live in every Central American nation and are working their way through Panama.

A recent survey of coyotes and crab-eating foxes in Panama revealed that two species now have an overlapping range. The crab-eating fox (Cerdocyon thous) is widespread in northern South America, but only recently did a few of them wander into Panama.  This survey used a combination of camera trap and road-kill data to get an idea of where both canids live in the country.

Deforestation in Panama has opened up new territory for both species, which do much better in human-dominated environments.  Coyotes now are at the edge of the great forests of Darien. Beyond those forests lies Colombia– and a whole new continent.

Further, coyotes could possibly enter Colombia through a coastal approach, simply crossing onto the beaches of eastern Panama and walking down the coast.

Also, the researchers are noticing that some coyotes have dog-like features, which suggests they are interbreeding with village dogs. The dogs could confer onto the coyotes some advantageous genes that might make colonization of South America easier.

So my guess is it won’t be long before coyotes make it to Colombia, and when they do, they will be the first wild Canis species to enter that continent since the dire wolf.

No, they aren’t as impressive in their forms as that creature was. But they are impressive in how they have thrived despite all humans have thrown at them.

Of course, when Panama was a province of Colombia, Panama was considered part of South America, and if that were still the case, we could already say they colonized the continent.  Many old maps of South America show Panama sticking off upper left of Colombia.

But whatever one thinks, coyotes are very likely to make it into Colombia. They will likely spread from there throughout northern South America. What this means for the native species of South America, we can only conjecture.

But it is going to be an interesting mess.

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dare wolfdog

One of the great controversies in the dog world is whether the German shepherd is a wolf dog. I will admit that I am agnostic on the subject. It might be, and one of the component regional German sheepdogs from which they were derived was rumored to have been crossed with wolves.

I have never been able to track down the exact truth of the wolf in the German shepherd, but I should note that lots of breeds have wolf in them and not all of them are as lupine in phenotype.  Several French griffon hounds, one of which was crossed into the otterhound, were mixed with wolf, because the French houndsmen believed such crosses were better hunters of wolves. The Plott hound is said to have at least one wolf crossed in at some point in its history, and various livestock guardian breeds, including those in Georgia and Turkey, are known to have wolf blood. And we know that Norwegian elkhounds and related Scandinavian spitzes have wolf ancestry, and some Russians have crossed their laikas with wolves, too.

In the annals of this blog, I have documented wolves being used in much the same way dogs have. I have documented wolf and dog crosses that proved useful as working and hunting animals.

So I am not at all unwilling to accept that German shepherds are wolfdogs. I just need proof. The GSDs that I have had tested with Embark have all come back with “low wolfiness” scores. “Wolfiness” is just the amount of ancient wolf DNA that a dog might possess, but it can also be indicative of some wolf crossed into the dog’s ancestry.

I have hear rumors that the original SV (Schäferhund Verein) studbooks do list wolves in foundational pedigrees of German shepherds, but I have not seen them.

I have come across this dog on Pedigree Database. The name “Wolf Rüde” translate as “Wolf Male Dog.”  Its pedigree is mysterious. The sire line is the typical tightly-bred sheepdog strains that are the basis of the breed. But the dam line is a mysterious creature called “Gerta Hündin.” The terms Hündin and Rüde mean “bitch” and “dog” in English. I cannot figure out who these dogs were, but the name of one of them is tantalizing in that it might be the name of an actual wolf in the foundational pedigree.

People have been breeding wolves to German shepherd ever since German shepherds became a breed. We have several off-shoot breeds that are wolf-German shepherd crosses. Only the Czechoslovakian wolfdog and the modern Russian Volksoby have shown any promise as being able to do the German shepherd’s job as a military dog. And they aren’t nearly as good at it.

I do know of a story of a first cross between a German shepherd and a wolf in Czechoslovakia that turned out to be a superior working animal. This dog apparently passed all requirements for breeding a German shepherd in that former country, and it even made it as a guide dog.  I have been unable to track down the full story of this dog, but it has always interested me in that this creature might be the hopeful monster that could have led to greater crossings between wolves and German shepherds in some working dog programs.

Also, we must tease apart some of the eighteenth and nineteenth century zoological ideas about sheepdogs and wolves. Buffon believed that sheepdogs of France were the closest to the wolf. I have even come across accounts of collies and what became border collies in which the author mentions how wolf-like the dogs are. In that sort of intellectual milieu, it is possible that someone might mis-translate or even get lost on a flight of fancy that these German herding dogs were wolves.

Further, it is one thing to have independent working dogs like scenthounds, hunting spitz, and livestock guardian dogs with wolf blood. It is quite another to breed a wolf to a herding dog, and it is even more to expect that herding dog with wolf ancestry to become an extremely biddable utilitarian working dog.

I will just say I want the evidence. I actually do want to believe that these dogs do have wolf in them, but the evidence is lacking– at least in English.

I am also fully aware that when the breed was introduced to the English-speaking world, there would have been a definite reason to downplay wolf ancestry in the dogs. Most of the English-speaking countries were major sheep producers, and in Australia and North America, wild canids were heavily hunted to make way for sheep husbandry.

So if anyone has the goods. Please let me know. I am certain that German shepherd blood has entered the wild wolf population in Europe. German shepherd makes up a large part of the street dog population in Eastern Europe, where there are still lots of packs of wolves.  We now know that the majority of Eurasian wolves have recent dog ancestry, and German shepherd blood course through the veins of some of these wolves.

It just isn’t clear to me that the introgression went the other way.

 

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A black Italian wolf. The black trait originated in dogs and was transferred to Italian and North American wolves through introgression.

As long-time readers of this blog know, I consider dogs to be a form of gray wolf.  I do not consider Canis familiaris to be a valid taxon, because of cladistics and because of the gene flow between domestic dogs and wolves.

The extent of this gene flow was largely denied in much of the literature on wolves.  But last year, it was discovered that the majority of Eurasian wolves have recent dog ancestry. This gene flow has been going on for a while, and although people do get a bit worked up about domestic animal genes filtering into a wild species, it has been shown that the melanism in wolves that is conferred by a dominant allele originated in a Native American dog that was living in the Yukon or the Northwest Terrtories thousands of years before Columbus. Further, this melanistic allele is associated with higher immune responses, and there is evidence for natural selection favoring black individuals following a distemper outbreak.

In a paper released this week in the European Journal of Wildlife Research found extensive crossbreeding between dogs and wolves in agricultural landscapes in Central Italy.  The authors estimate that about half of all wolves in this region have recent dog ancestry, and they think it is because humans have disturbed wolf habitat to have agriculture.

Of course, humans, wolves, and dogs have been living in Italy alongside agriculture for thousands of years. Dogs and wolves have been mating ever since there was a population of somewhat domesticated wolves.

Further, European wolves are much better adapted than North American wolves to living in agricultural areas.  It may simply be that North Americans are much more likely to kill wolves that appear in agricultural areas and that this is what has created this asymmetry. But North American wolves tend to be in remote areas, where they rarely encounter dogs. Thus, there is not as much gene flow between dogs and North American wolves as there is between dogs and Eurasian wolves.

There is a lot of gene flow between dogs and coyotes in North America, and this finding does make sense. Coyotes do live in agricultural and urban areas much more easily than large wolves do.

I don’t think it worth becoming alarmed that dogs and wolves are mating in the wild.  Dogs have lots of interesting mutations that could be of great use to wolves as they adapt to more and more human-dominated planet. If the dog alleles are deleterious, nature will select against them, but if they are advantageous, they will help wolves thrive into the future.

So it is quite short-sighted to think of wolves as being a some sort of pure entity that must be kept free of “foreign” alleles.  If it were more widely accepted that dogs were just a domestic form of gray wolf, we would have a much easier time accepting a more holistic understanding to how these populations can continue exchange genes and adapt to new challenges.

 

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yakutian megafaunal wolf

The Siberian Times reports that the head of a massive wolf was discovered in the permafrost in Yakutia (Sakha Republic of Russia).  The head includes much of the soft tissue, as well as its golden-colored fur. The head is 40 cm (15. 7 inches long), which is pretty large when compared to modern wolf specimens.

Researchers in Russia and Japan will be examining the DNA from the soft tissue to see where it fits in modern wolf and dog phylogeny of which there are still many questions.

This wolf is a good example of what have been termed “megafaunal wolves,” very large gray wolves that lived during the Pleistocene. Robert Wayne of UCLA, a leading canid molecular geneticists, thinks that some form of Pleistocene megafaunal wolf is the progenitor of the domestic dog.  These wolves would have been expert hunters of large bison, reindeer, and horses, and they may have been semi-nomadic, following large herds of ungulates across the steppes and taiga. These semi-nomadic wolves would have been quite easily attached to humans, who were hunting and traveling in much the same way.

Also of note, this wolf has golden colored fur.  In 2015, I postulated a speculative hypothesis that the original Pleistocene wolves were more often golden in color, rather than gray.  When humans started hunting wolves extensively during the Neolithic and into modern times, wolves that were gray were selected for because they could more easily hide from human hunters. Gray color in the dead of winter in many European and Western Asian forests would have been great camouflage against the winter tree trunks and undergrowth of the forest.

Some wolves, especially tundra wolves from northern Russia and Finland, are still often golden in color, as are those in Central Asia.

Golden sable color is quite widespread in domestic dogs, but it is far less common in wolves. So it is quite possible that this coloration is so dominant in domestic dogs because the wolves that gave rise to them were this color.

This massive wolf with golden fur certainly adds some credence to my speculations, but only time will tell what this ancient, massive wolf’s head has in store for us.

But is an amazing find. No doubt about it!

Update: Researchers in Sweden, not Japan or Russia, will be examining its DNA. 

 

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