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Posts Tagged ‘dog family’

dog-phylogenetic-tree

The shell of my canid classification begins with this phylogenetic tree that comes from a complete sequencing of the domestic dog genome.

What I am about to write is a very tentative taxonomic system, and I reserve the right, as would anyone, to revise it.

Here’s how I would classify the dog family in terms of cladistics.

The first thing I would do is that we have to split the dog family into tribes, which will create the clades where I will put the species.

Traditionally, there have been just two tribes for extant canids, but I think a third one is necessary.

The two traditional ones are Canini (Canis, its allies, and the South American wild dogs) and the Vulpini (which inlcudes all the foxes, including the Urocyon gray foxes and island foxes). I would argue, that because the Urocyon foxes are quite divergent from the rest of the dog family, they need their own family. They split from the rest of the dog family 9-10 million years ago.

So my tribes are Canini, Vulpini, and Urocyoni.  In Vulpini, I will put all the Vulpes foxes, the bat-eared fox, and the raccoon dog. The arctic fox and the fennec fox are now both Vulpes foxes. Canini will remain the same.

I do not believe in paraphyletic groupings within my classification, so you will notice some weird things about it very soon.

Let’s start with Canini.

In Canini, we have CanisLycalopex, Cerdocyon, Chrysocyon, Speothos, and Atelocynus. I have done away with Cuon and Lycaon.  The reason I have done so is to keep the genus Canis monophyletic. Traditional classifications have these two species, the dhole and African wild dog, as belonging to distinct genera, but they are likely sister taxa. Further, they are also less removed from the rest of Canis than the black-backed and side-striped jackals are. The rest of the genera are endemic South America canids. Two of these, Cerdocyon and Speothos, occasionally enter Panama, but they mostly a South American species.  North America was the original place of dog evolution and diversification, but today, North America is home to only three genera, the very common Vulpes foxes, Canis dogs, and the Urocyon gray foxes. Endemic North American dogs largely slipped down in South America, which is why South America is home to so many quite diverse species of canid. But all derive from North America ancestors with which they share a common ancestry with Canis.

In Vulpini, I have placed the bat-eared fox and the raccoon dog with all the Vulpes foxes.I have also split the native raccoon dog of Japan, the tanuki, into its own unique species. It has a 2n count of 38, while the mainland raccoon dog is 2n=54.  I have suggested that its scientific name should be Nyctereutes viverrinus.  I also think that evidence is pretty clear that North American red foxes are divergent enough from the Old World red foxes to be given their own species, Vulpes fulva.

In Urocyoni, I would have but a single species, because it turns out that island foxes probably split much more recently that was previously thought.  In this case, I would say that the island fox is a insular dwarf subspecies of the mainland Urocyon, and it will have but a single species in it.

So allow me to list my species in their tribes.

In tribe Canini:

Genus Canis:

  1. Black-backed jackal (Canis mesomelas)
  2. Side striped jackal (Canis adustus)
  3. Dhole (Canis alpinus, instead of Cuon alpinus).
  4. African wild dog (Canis pictus, instead of Lycaon pictus).
  5. Eurasian jackal or golden jackal (Canis aureus).
  6. African golden wolf (Canis anthus, which used to be a golden jackal).
  7. Ethiopian wolf (Canis simensis)
  8. Coyote (Canis latrans)
  9. The wolf/dog/dingo species (Canis lupus).

I do not recognize domestic dogs as distinct species from the Holarctic wolf species, and I also do not recognize the red wolf or Eastern wolf as valid species. Domestic dogs are essentially a specialized wolf that can live with and easily read human beings. Dingoes, despite rather desperate attempts to make it otherwise, are nothing more than an East Asian feral dog that has made its home in Australia. Eastern wolves and red wolves are recent hybrids between wolves and coyotes that occurred after European settlement of the continent. It was only recently revealed that the African golden jackal was quite genetically distinct from the Eurasian golden jackal, and now that species has been divided into Canis anthus and Canis aureus.

So that’s the genus Canis. 9 species. There are potentially two more, because it turns out that two wolf populations, one in India and one in the Himalayas have rather unique mitochondrial DNA sequences. It would be interesting to see how those two populations within a genome-wide analysis.

The rest of Canini are all South American endemics.

Most are in the genus Lycalopex. Here are the species:

  1. The culpeo (Lycalopex culpaeus).
  2. The chilla or “South American gray fox” (Lycalopex griseus)
  3. The Pampas fox or Azara’s fox (Lycalopex gymnocercus)
  4. The Hoary fox (Lycalopex vetulus)
  5. The Sechuran fox (Lycalopex sechurae)
  6. The Darwin’s fox (Lycalopex fulvipes)

The word “Lycalopex” is a combination of the Greek words wolf and fox (“lykos” and “alopex.), and they actually do look like bantamized wolves or coyotes. Indeed, I’ve seen less-informed people use photos of culpeos as coyotes.

They are superficially fox-like. I have seen them called foxes and zorros my entire life, but it is hard to explain to people that these animals are much more closely related to wolves and dogs than they are to foxes.

Also, it has only been since 1996 that the Darwin’s fox has been given full species status. It was previously thought of a subspecies of chilla that lives only in the temperate rainforests of Chile, but when its mitochondrial DNA was compared to several chillas, it was found that they were quite distinct from each other. The Darwin’s fox is most closely related to the Sechuran fox, which also has a very narrow range along the Pacific Coast of Ecuador and Peru. Darwin’s fox is arguably the most endangered of all canids. It lives on Chiloé Island and Nahuelbuta National Park. A small population was also discovered in Valdivian Coastal Range.  There are only about 250 of them on Chiloé Island and about 70 on the mainland. That’s an estimated 320 individuals, which is a bit more than the estimated 350-440 Ethiopian wolves. For some reason, we tend to hear more about Ethiopian wolves than Darwin’s foxes, but they certainly are deserving of our attention.

I should note that the genome-wide analysis found the Darwin’s fox to be a bit more divergent from the Sechuran fox, which was closer to the culpeo. So it does need a bit more work to figure out how those relationships work.

The rest of Canini are what I call the South American weirdos. This is where canid evolution went a little strange. Here we have a dog on stilts, a basset-type dog with the dhole’s trenchant heel dentition, a dog that lives on a lot fish, and one that eats crabs. Also, the only dog species to have gone extinct in historic times is here too.

So here are the species:

  1. The maned wolf (Chrysocyon brachyurus)
  2. The Falkland Islands wolf (Dusicyon australis)
  3. The bush dog (Speothos venaticus)
  4. The crab-eating fox (Cerdocyon thous)
  5. The short-eared dog (Atelocynus microtis)

The Falklands wolf is now extinct. It was an unusually curious animal that was soon killed off to make way for sheep farming. No one knew what it was related to until just a few years ago, when it was discovered that its closest relative was the maned wolf. It has been suggested that this animal was a living fossil that resembled the ancestral South American canid that came down into that continent from North America before branching into the Lycalopex and “weirdo” forms.

The maned wolf itself looks like a large red fox with really, really long legs. Its closest living relative is the bush dog, which is the only native pack-hunting canid in South America. It looks like an unholy hybrid of a basset hound and otter, and it has evolved the dhole and African wild dog’s trenchant heed dentition in parallel. It was even suggested at one time that it was a type of New World dhole, based solely upon the teeth.

The last two are closely related enough that one might be able to put them in a single genus. The crab-eating fox is pretty common in South America, and it is often seen out on beaches and river banks searching for food. It was commonly seen eating crabs, so it got that name. The short-eared dog, its closest relative, is almost never seen and has hardly been studied. It is perhaps the strangest dog still in existence. It has a long, bull terrieresque muzzle and little rounded ears. It has been known to eat quite a bit of fish in its diet, but other than that, very little is known about them. They live in very low densities in the Amazon Basin.

We have finished the Canini tribe, now onto the Vulpini.

The Vulpini go as follows:

First the genus Vulpes:

  1. Old World red fox (Vulpes vulpes)
  2. North American red fox (Vulpes fulva)
  3. Rüppell’s fox (Vulpes rueppellii)
  4. Corsac fox (Vulpes corsac)
  5. Tibetan fox (Vulpes ferrilata)
  6. Swift fox (Vulpes velox)
  7. Kit fox (Vulpes macrotis)
  8. Arctic fox (Vulpes lagopus)
  9. Blanford’s fox (Vulpes cana)
  10. Bengal fox (Vulpes bengalensis)
  11. The Cape fox (Vulpes chama)
  12. The pale fox (Vulpes pallida)
  13. The fennec fox (Vulpes zerda)

The exact relationship between fox species isn’t that clear, but generally, most authorities recognized that kit and swift foxes are distinct species, even though they do have a limited hybrid zone. It is also clear that the arctic fox is a very close relative of those two species, and perhaps the best way to think of the arctic fox is that it is a swift fox that has become specialized to the arctic ecosystems. As I mentioned earlier, a study at UC Davis found that red foxes in North America diverged from the Old World red fox 400,000 years ago.  This divergence is enough to make some consider them a distinct species, and it should be noted that even red foxes that were said to have derived from European imports that were released on the East Coast are also just as divergent. Which means they aren’t derived from these imports, as was initially believed.

The addition of the others in Vulpini are a bit more controversial, but I’ll say that bat-eared foxes are vulpines, as are raccoon dogs. So the rest of Vulpin is:

  1. The bat-eared fox (Otocyon megalotis)
  2. The common raccoon dog (Nyctereutes procyonoides).
  3. The Japanese raccoon dog or tanuki (Nyctereutes viverrinus).

All of these are earlier offshoots of the fox lineage, but they are close enough to foxes to be considered Vulpini. As mentioned earlier, there are good reasons to think that the tanuki is a distinct species, but its exact status is still somewhat controversial. Bat-eared foxes have the most teeth of any canid, and they pretty much eat nothing but harvester termites. They are found in disjointed populations in East Africa and Southern Africa.

And finally, I have made the decision to raise the Urocyon “foxes” to their own tribe, and because of their genetic similarity, I have reduced them from two species to one.

So tribe Urocyoni is:

  1. The North America gray fox or tree fox (Urocyon cinereoargenteus).

So in my classification of Canidae, I have 36 living species, with two more that could be identified in the form of the Indian and Himalayan wolves.

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I’ve actually run into this statement quite a bit:

We can’t know much about dogs by studying wolves. It’s about as much as we could find out about human behavior while studying chimps and bonobos.

That’s a cute one!

Unfortunately, it’s a bad analogy.

Dogs are not to wolves as humans are to chimps and bonobos.

Dogs are to wolves what modern humans are to archaic Homo sapiens.

It’s also not dogs are to wolves as humans are to Neanderthals. That analogy would be dogs are to coyotes, golden jackals, or Ethiopian wolves as humans are to Neanderthals (and maybe Denisovans and other descendants of Homo erectus). Same genus. Chemically interfertile.  Not the same species.

We can actually learn quite a bit about ourselves by studying humans who were around until 30,000 years ago but were much more robust than any living person.

The line that divides modern humans from archaic Homo sapiens is quite fuzzy, just as it is with defining the difference between dogs and wolves.

Contrary to what you may have read, the line separating dog and wolf is very, very fuzzy. There are doggish wolves and wolfish dogs, and the only physical features separating them are that wolves (at least  of the northern subspecies) lack sweat glands on the feet and dogs don’t have an active supracaudal gland. There are dogs that have brains that are proportionally the same size as those of southern wolves, which are the main source for modern domestic dogs.

There have been wolves  that were tamed at 6 weeks, and even fully grown adults have been tamed.

And there are dogs that are so nervous and hard to handle that they might as well be wild animals.

Humans are not chimpanzees or bonobos.

We’re actually much more different from them than dogs are from wolves.

For example, most people would never want to breed with a chimp, and humans, unlike male chimps, typically only attempt to devour the faces of other humans while high on bath salts.

However, there are plenty of cases of dogs and wolves interbreeding. Studies of free-roaming dogs and wolves in Italy found that female wolves that had not yet found a mate, would often solicit the attention of male dogs while in estrus.

Most single women don’t want to go on a date with a chimpanzee!

(Though bonobos, well, they are the doctors of love.)

When I see someone using this analogy, it makes me wince.

I know people are trying hard to fight the Cesar Millan-malarkey out there.

But too often, I see these anti-lupomorph or dominance theorists making claims that are just as bad as anything you’d hear from the Dog Whisperer.

Let’s try to get our analogies right.

Let’s understand what we’re actually opposing.

It’s not the entire phylogeny of Canis lupus familiaris.

Just because idiots use that Canis lupus part of the scientific name to make stupid arguments doesn’t mean that you should reflexively reject it.

We’re not exactly the same thing we were 30,000 years ago.

Neither are dogs. (And really, neither are wolves).

Evolution is about change. It’s almost the entire definition of the phenomenon.

But just because things change doesn’t mean analogies don’t work.

It just means they have to be correct.

You can learn more about us by looking at our more immediate ancestors than from animals that derive from more distant ones.

You can know more about your potential health problems by looking at your parents and grandparents than you great-great-great-great-great grandpa.

In terms of its phylogeny, a dog is a wolf.

It’s not anything else.

One cannot evolve out of one’s phylogeny.  One can only evolve from it.

Dogs and modern wolves evolved from ancient wolves.

If we saw these animals today, we’d call them wolves, though they’d likely be much more willing to approach us than modern wolves are. They might even be readily tamed and actively seek us out as social partners.

Dogs underwent selection pressures to become more and more incorporated into human society. Most wolves experienced selection pressures that selected for extreme fear and reactivity– the result of all those centuries of persecution by our species.

I doubt that archaic Homo sapiens would have ever fit into urban life. Some of them might, but most would not.

It doesn’t mean that they were a different species from us.

It just means that there were lineages of our species that were adapted to an entirely different lifestyle and potential future.

That’s the difference between wolves and dogs.

They aren’t as different from each other as humans and other great ape species are.

But there are differences.

Nuanced, fuzzy differences.

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Kent Hovind misuses the Belyaev fox farm experiment to claim that all the dogs, both wild and domestic, came from two of the "dog kind" that were on the ark.

 

 

Boy, this is a good one!

First, let’s look at some facts regarding dogs. Most experts say there are about 400± recognized breeds of dogs in the world today. Most also agree that they are all interfertile (can produce puppies) and are therefore the same “kind” of animal. Ten times in Genesis chapter one, God said the plants and animals would bring forth after their “kind,” not their species.

The use of the word “species” sometimes clouds our communication, as there has never been an airtight definition of the word “species.” Darwin’s book entitled, On the Origin of Species by Means of Natural Selection or the Preservation of Favored Races in the Struggle for Life never does tell us about the ORIGIN of species at all. He only covered his unproven ideas on how he thinks species might have changed over the “millions of years” he claimed that the world has possibly been here.

It is true that there are a wide variety of dogs on earth today but please consider the following list of facts. Yes, my mind works best from lists. :

All the evidence that mankind has ever been able to observe shows us that dogs produce dogs.

While there are small dogs and large dogs, there seems to be a limit. I would be willing to bet no one will never get a dog as small as a flea or as big as Texas.

Dogs also seem able to “adapt” to various climates. Some can survive at -30F in Alaska and others have “adapted” to ±120 in deserts. Again however, there are limits. They will never adapt to ±300F! Or 10,000F!!!

I have had several people who raise dogs for a living tell me that they can take fifty generic “mutts” from the dog pound and, with selective breeding, re-create nearly every breed of dog today in less than 100 years.

Richard Dawkins, famous English atheist who hates creationists (See the movie, “Expelled”. You can purchase it by clicking here), wrote a book in 2005 called The Ancestor’s Tale. On pages 29-31, he tells of a Russian science team that took captive silver foxes and bred them for “tameness.” In twenty years, they watched them change into dogs! They looked like border collies, sought human company, wagged their tails when approached, had black and white coats, had dog-like muzzles and “lovable” floppy ears, developed hormone changes to breed year round, and displayed less aggression. I think you will find that nearly everyone (creationist or evolutionist) agrees that all dogs could have descended from foxes or wolves with no problems.

To look at the really big picture, I think it is funny to listen to an evolutionists ask a creationist, “How could all the dogs in the world come from just two dogs on Noah’s ark?” and then turn around and teach that all the dogs in the world came from a rock! Over billions of years of course! (Or quickly if you are from Harvard!) On page 31 of The Ancestor’s Tale, Dawkins says, “It is entirely probable that cattle, pigs horses, sheep, goats, chickens, geese, ducks, and camels followed a course which was just as fast and just as rich in unexpected side-effects.”

Keep in mind that the changes needed to turn a wolf, fox, or jackal into a dog are minor compared to turning a rock into a dog or even an amoeba into a dog. I’m even willing to let them have the huge head start of not dealing with the major problem of the origin of life issue and letting them start with a hamster (already a mammal, air-breathing, and land-dwelling) and see if they can turn it into a dog.

Don’t be thrown off track by those who question God’s Word with their detail questions about Noah’s ark. I think there are plenty of great answers to nearly all the questions the atheists raise and I cover many of them in the Creation Seminar. For the questions for which we don’t have answers yet, keep seeking for truth and God will provide the answers as we go and as we need them.

***

Of course, he makes no mention of what that dog kind was. We all know from credible creationist sources that this “dog kind” was the Afghan hound. That means that all dogs from gray foxes to bulldogs to maned wolves descend from that animal. Of course, that would that mutations occur within populations at a startling rate to create such amazing genetic and morphological variation.

***

Hovind is right that the term species is very nebulous. I don’t consider domestic dogs to be a separate species from wolves, and I am skeptical that the red wolf and the Eastern timber wolf are separate species from the rest.

That said, I don’t think foxes are the same species as wolves. I don’t think dogs descend from foxes. I don’t know of a single person with any kind of credibility who thinks so. (No. Chihuahuas are not derived from fennec foxes!)

However, Kent thinks that’s a possibility because of the Belyaev experiment. He thinks that they actually created dogs (as in the same species as domestic dogs) through selecting for tameness alone. Yes. They look like border collies, but they are not border collies. They are genetically tame red foxes of the silver phase. This study is used as an analogy to see how domestication might have worked in domestic dogs in their evolution from wild wolves.

Hovind is correct that you could take a large population of randomly-bred dogs and, through an intense selective process, produce something like all the dog breeds we have today. That’s actually what happened in the past 150 years. The many generic and specialist working-type landraces were selected and “improved” into many different breeds. That happens because dogs are very susceptible to selective breeding. Although no one has bred one the size of a flea or the size of a Texas, but we have produced 20o-plus pound English mastiffs and chihuahuas that weigh less than two pounds. This diversity is reflected in the wild Canis lupus species, which once existed in such diverse forms as the 25-pound Honshu wolf to the giant Pleistocene wolf of Alaska with bone crushing jaws.

One of the reasons why dogs and wolves vary so much in appearance is just a little variation on a few genes have great effects upon phenotype. Just slight variations on one gene produces the great variance in size in domestic dogs. In addition, their DNA has an unusually high number of tandem repeats, which also means that they can rapidly evolve diverse phenotypes.

But if Hovind thinks the whole 35ish species in the dog family are derived from just two individuals of the “dog kind,” he must believe in super evolution. While it is true that golden jackals, coyotes, and Ethiopian wolves can crossbreed with both wild and domestic Canis lupus, fertility issues exist when dog/coyote and dog/golden jackal hybrids are bred to each other over the generations. These fertility issues strongly suggest that golden jackals and coyotes are distinct species, despite the fact that many of these hybrids are fertile.  Although there is some anecdotal evidence that a crab-eating fox (which is a South American wild dog, a close relative of the genus Canis) crossed with a domestic dog, there have been no verified dog and fox hybrids. The dhole and painted wolf/African wild dog (Lycaon pictus) cannot hybridize with the members of the genus Canis, and no verified hybrids exist between black-backed jackals and side-striped jackals and other members of the genus Canis.

These animals cannot interbreed because they vary too much genetically.

How could all of this variation result from two dogs (which we all know were Afghan hounds) that were on the ark? We all know that breeding from two dogs in such a fashion would produce animals that have very little genetic diversity. They likely wouldn’t be able to reproduce after just a few generations of breeding from such close relatives.

Hovind totally misunderstands the literature on the dog family. Yes. The Belyaev experiment is very useful in seeing how the domestication process alone might have created all the interesting phases and types that occur in domestic animals.

The silver-phase red foxes in this experiment did become dog-like. They were still red foxes. They did not become dogs.

Would you take tax advice from someone like this?

 

 

 

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