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Posts Tagged ‘crab eating fox’

crab-eating fox coyote

In the US and Canada, there has been much discussion about how coyotes have been able to colonize so much territory. They were pretty much a Western species that was able to colonize land that had been previously occupied by wolves. We killed the wolves off and did the same with coyotes. The wolves became exceedingly rare and extirpated from much of their range. The coyote’s range expanded.

We know this well. It’s one of those wildlife stories that North Americans know well. The fact that they are found in new areas mean that it’s actually quite common for people to call them an invasive species, which is a bit erroneous. Coyote-like animals have been living North America for millions years, and this current form, which is perhaps more closely related to wolves than the previous models, is something our ecosystems have been putting up with for quite some time. Coyotes or coyote-like animals lived in the East all through the Pleistocene. the current form isn’t invasive but reclaiming lost territory.

The thing about coyotes, though, is they are expanding their range to the south as well. Most of us are aware that coyotes live in Mexico. The term coyote is derived from the Nahuatl coyotl, which supposedly means “barking dog,” and their range expanded to the south as well. The tropical forms of coyote were probably always present in southern Mexico and northern Central America,  but today they are found to the eastern part of the Panama Isthmus. This eastern part is the part that attaches to South America, and should coyotes continue to expand their range in Panama, they will probably cross into Colombia. These southern coyotes are expanding along the Pan-American Highway and the expansion of cattle ranching in the region.  The current thinking is they may not make it South America until and unless the highway is built across the province of Darien into Colombia, which has generally been put off as unfeasible.

I don’t know if I would put much stock into the road being the only way that coyotes get into South America, because as coyotes began this expansion south, another species of canid began its expansion north out of South America.  The crab-eating fox is quite common in northern South America, and it started showing up in Panama in the 1990s.  This animal is experiencing a range expansion in Colombia, using open areas around the Pan-American Highway as its habitat, just like the coyote in Panama. One recently was captured on trail camera near the Panama Canal.

That means that crab-eating foxes were able to cross the relative wilderness of Darien to get deeper in Panama.

It also means that coyotes could quite possibly cross Darien into Colombia, just as the crab-eating fox went the other way.

Much stock has been placed on the fact that coyotes prefer open habitats, but I wonder if this is missing something else that could have led this territory opening up for coyotes. Central American jaguar and cougar populations are on the decline. With the larger predators becoming rarer, smaller ones can begin to fill in, just as coyotes did when wolves were wiped out of most of the Lower 48.

Coyotes in my part of the world make use of forested habitat quite extensively. It is very rare to see one out in the open during the day, but you can see them out and about in the woods during the day. Granted, I’m talking about temperate deciduous forest, and that which exists in Panama is tropical forest. But I’d be very surprised if coyotes didn’t use the habitat.

So if the crab-eating fox is able to work its way into the North American continent a little deeper, why wouldn’t the coyote be able to go the other direction?

Further, the crab-eatng fox isn’t the only South American wild dog to wand up into Panama. The much rarer and much more elusive short-eared dog has crossed from Colombia into Darien at least once. Unlike the other two species, it is a much more forest dependent animal, so even if it were to spread, it would only be found in forests.

But the fact that something as weird and as specialized as a short-eared dog would take the baby steps pretty much would hint that something as bold as a coyote could easily take the steps in the other direction.

So dogs are moving north, and dogs are moving south.

And if the coyote makes it into Colombia, it will be the first creature from the wolf lineage (other than domestic dogs) to do so since dire wolf came into the continent. When the dire wolf came, it was a big, packing creature that readily hunted camelids and other ungulates. Now a meeker and more generalized offshoot of that lineage is working its way toward South America.

They may not make it.

But I honestly wouldn’t bet on it.

They didn’t need a road to get them from Kansas to Nova Scotia, and I bet they really don’t need a road to get them from eastern Panama into Colombia.

And after the hit South America, I think it’s quite time that Australia got a chance to enjoy coyotes. They will keep red fox numbers in check. What could possibly go wrong?

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Source.

Indigenous peoples of South America have often tamed crab-eating foxes.

This particular fox wound up going to a zoo as he matured.

Which is probably for the best.

However, from what I understand, those that the indigenous peoples kept very often returned to the wild when they reached sexual maturity, not unlike the dingoes Carl Lumholtz described.

I’ve read that the crab-eating fox is capable of producing infertile hybrid offspring with domestic dogs, but I have found no verified accounts– you know, that have a chromosome analysis.

So rumors of hybrids may just be nothing more than urban legends or a complete misidentification of the indigenous dogs of South America.

***

You’ll note that I call the offspring of this species a puppy, not a kit.

The reason is simple: a crab-eating fox, like all South American foxes, is not a true fox.

True foxes have kits.

South American foxes (and all South American wild dogs, except the Urocyon gray foxes that live in Venezuela and Colombia) are much more closely related to the true dogs of the genus Canis and its allies, Lycaon and Cuon.

Those animals have puppies, so to reflect that evolutionary relationship, I suggest that we refer to the offspring of South American wild dogs in the same fashion.

The Linnaen names of some of the genera of South American wild dogs clearly reflect this relationship.

Most South American foxes are in the genus Lycalopex, a combination of the Greek words for wolf and fox– “Lycaon” and “Alopex.”

The crab-eating fox’s name is Cerdocyon thous. “Kerdo” also refers to a fox in Greek, and “cyon” refers to a dog. The genus name reflects the mixture of dog and fox characteristics in this animal, and thous is in reference to the old genus name for the jackals, Thos.

More interesting, though, is that all of these diverse South American dogs experienced much of their evolutionary history in North America.

North America used to have a great diversity of canid species, but these animals shifted south when the  Isthmus of Panama formed.

With the exception of our two Urocyon foxes, all of North America’s wild canids are either in the genus Canis or the genus Vulpes, not unlike the majority of canids in the Old World.

South America’s diversity of canids is one of its more interesting features of its natural history.

Nowhere else in the world, except in domestic dogs, are there such diverse forms.

Where else are there bush dogs that are like dachshunds crossed with otters, maned wolves that look like red foxes on stilts, and short-eared dogs that are like nothing else on earth.

South American wild dogs are fascinating animals, just because they are so different from what we expect.

 

 


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Could the Fennec fox be the Chihuahua's ancestor? I'm going to have to go with no on that one.

Could the Fennec fox be the Chihuahua's ancestor? I'm going to have to go with no on that one.

Dog breed origin stories are often like creation stories in religions. They are full of bad information, poor speculation, and it is difficult to find evidence any evidence that is not tautological or really bad hearsay. In golden retrievers, we have the Russian circus dog theory, which has been so clearly disproven, that I am not going to rehash it here. As near as I can tell, though, this has been the only folk story about breed origins that has been disproven. Although the FCI has raised doubts the Dalmatian actually came from Croatia when it claimed that it was the result of crossing pointers and setters with bull and terrier-types in eighteenth century in England, no one has disproven the Croatian dog story. The dachshund is said to have a history going all the way back to Ancient Egypt, where it is pictured on the walls of tomb of one of the pharaohs!

The Chihuahua dog has a similar dubious origins story. Supposedly this breed originated in Mexico as one of the Toltecs’ sacred animals.  It is supposedly a Native American dog, like the extinct Tahltan Bear Dog (which did look like a big Chihuahua). And the Pre-Columbian indigenous peoples of the Americas were major dog breeders, breeding all sorts of hairless dogs, wool dogs, and various types of dogs that could be either eaten or as beasts of burden. The Aztecs did have a little dog, called a Techichi, but analysis of the Chihuahua’s DNA suggests that it is of Old World origin, perhaps derived from some European toy dogs and maybe some toy terriers with apple heads.  Again, the original story has not yet been disproven, because the DNA analysis looked at only mitochondrial DNA, which only is inherited through the mother. So the fathers of the Chihuahua could have been the Techichi.

However, of all the bizarre theories I’ve read about a dog breed’s origins, this alternative theory about their origins takes the cake. Apparently, the author thinks that the Chihuahua got its small size from hybridization. Now, some theories about dog origins do include hybridization. Charles Darwin was a major proponent of the theory that dogs were derived from a medley of foxes, wolves, coyotes, jackals, and dingoes. In the twentieth century,  Konrad Lorenz  postulated that dogs were a mixture of wolf and golden jackal in Man Meets Dog   This hybridization gave rise to great genetic diversity and new shapes and forms could be brought out of the hybrid soup. However, this theory has been falsified. Dogs come from an East Asian population of wolves, and the wolf  is their primary and perhaps sole ancestor.

Now, the problem with this theory of Chihuahua origins is  that the author is arguing some things that do not comport with what we already know about world history and the development of all of these dog breeds.

First of all, the only hairless dogs that have ever been proven to exist are American in origin. Even the Chinese crested is American in origin, coming from a kennel where Xoloitzcuinli (Mexican Hairless dogs) were crossed with fuzzy lap dogs. China hadnothing to do with them.  The whole dog breeds coming from China to the New World thing is not supported by the evidence. The hairless dog stories are common in popular dog literature, but that part of the theory is still somewhat believable. Luckily, the author recognizes that hairless dogs are not related to Chihuahuas. However, it is possible that the dogs that Chihuahuas were crossed in to make the smaller Xolo dogs. The Xolo is indeed indigenous America breed, although it probably has European dogs in its mitochondrial DNA sequence.

Also, dogs come from East Asian wolves, not Turkey or Mesopotamia. That whole part of the theory is simply wrong. So the Chihuahua isn’t from the Middle East.

In addition, Chihuahuas are terrier-like, perhaps because they were stray dogs of terrier ancestry living in Northern Mexico, and when they were imported to England, they were probably bred with the toy white terrier and the toy Manchester terrier. That would give them a really strong terrier-like temperament.

But the part of the theory that is most wrong. Is that the Chihuaha is descended from the Fennec fox, incorrectly classified here in the old genus Fennecus, which has since been changed to Vulpes,  the same genus as the red fox.  The foxes in the Vulpes genus live in the Old World and North America, and none of them can interbreed with dogs, wolves, coyotes, jackals, and dingo/pariahs. They are simply another genus that has evolved differently from the dogs to the point that they cannot interbreed. A dog breeding with a Fennec is just not possible. None of the foxes in the old world ever could breed with a dog. The other foxes that cannot breed with dogs are the Arctic fox, which may actually be in the genus Vulpes because it can hybridize with red foxes and make infertile hybrids, and the grey foxes (the ancient canids of North America, Central America, and Venezuela and Colombia that can climb trees) cannot breed with them  either.

However, the South American canids are interesting, and it is the discussion of these wild dogs that causes a great deal of confusion. The Europeans called the smaller species of South American canids foxes. However, these foxes are actually more closely related to the dogs, wolves, coyotes, dingoes/pariahs, and jackals. Marion Schwarz in A History of Dogs in the Early Americas reportst that a crab-eating fox (Cerdocyon thous) may have crossbred with domestic dogs. This species is more closely related to dogs than foxes, and the some indigenous people have kept them as pets, allowing them the opportunity to breed with dogs. Again, this is an anecdote, but it makes more sense that this animal would cross with a dog than the fennec.

This South American "fox" may have interbred with domestic dogs. It is more closely related to dogs than the animals we in the Northern Hemishere think of as foxes.

This South American "fox" may have interbred with domestic dogs. It is more closely related to dogs than the animals we in the Northern Hemishere think of as foxes.

Messybeast reports some stories about dog and red fox hybrids, but there was never any DNA analysis ever performed on them. They were probably foxlike dogs like this one:

volpinoitaliano1

The volpino is named for its fox-like features. Volpe is Italian for fox, and volpino is the diminutive. It is derived from the Latin word for fox, vulpes, which is the scientific name for the genus of red foxes and their close relations. However, these dogs do not have fox ancestors.

So the fennec is not the ancestor the Chihuahua.

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