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Posts Tagged ‘dog taxonomy’

African wild dogs (Lycaon pictus or Canis pictus) are more distantly related to dogs than humans are to chimps. African wild dogs cannot crossbreed with dogs, and they are not an ancestor of any domestic dog breed. This species has suffered greatly because of its common name. Many ranchers and pastoralists in Africa have persecuted this species under the suspicious that it is nothing more than a feral domestic dog. It’s not even an ancestor of the domestic dog. It’s a truly unique but endangered species.

Stanley Coren has posted a slide show on Huffington Post entitled Dog Facts: 10 Things You Didn’t Know About Your Pet.

I couldn’t get past the first slide because this is what it said:

How do scientists decide whether dogs started out as wolves? One way is to try to cross breed the species by mating a wolf to a dog. If that mating produces live puppies that are fertile and can have pups, then that means that the wolf and dog are the same species. It turns out that dogs can have puppies, not only with wolves, but also with jackals, coyotes, dingoes, African wild dogs, and even some kinds of foxes. Although genetic research says that the first species that humans domesticated was the wolf, the guess is that dogs are mixture of all of these different wild canines, which probably explains the existence of so many different looking dogs in the world.

Wrong.

One wonders if Coren consulted any of the genetic literature on domestic dogs.

It turns out that their wide variance in phenotype comes from two really basic weird aspects of the dog genome. One of these is that just few genes account for massive differences in phenotype in domestic dogs. Variation on just three genes produces almost all the variance in coat that domestic dogs. That’s somewhat shocking, I know.

Further, it’s been found that all dog species have an unusually high number of tandem repeats in their genes.  Selection selective breeding animals with such high numbers of tandem repeats often results in massive changes in phenotype within just a few generations. That’s why dogs breeds change so rapidly through the years.

Small size in most domestic dogs has been traced to a single gene that likely originated from domesticating the Middle Eastern wolf. Arabian wolves are often as small as 25-30 pounds– much smaller than other subspecies– and have also been implicated in providing a lot of the genetic material to modern domestic dogs.

Now, all the genetic literature points to the wolf as the primary and perhaps sole ancestor of the domestic dog. Coren totally screws the pooch when it comes to classifying the dog and its closest relatives.

Dingoes are not an ancestor of the domestic dog. They are  descended from domestic dogs that came to Australia from Indonesia as domestic animals. In every genetic study I’ve seen, dingoes group with East Asian domestic dog breeds, which also share an affinity with the Chinese wolf.

The best way to classify dogs, dingoes, and wolves is to count all three as belonging to the same species. Conventionally, dogs are Canis lupus familiaris, and dingoes are C. l. dingo. I think that in light of what we’re seeing in the genetic studies, dingoes ought to be classified as Canis lupus familiaris.  The basenji, which is always classified as a breed of domestic dog,  is actually much more genetically distinct than the dingo is.

So Canis lupus encompasses dogs, wolves,  and dingoes (including the New Guinea singing dog).

That species is interfertile with the coyote, and many coyotes have genes from wolves and domestic dogs. Certain wolves in Eastern Canada have genes from coyotes, and the so-called red wolf, which is primarily coyote in ancestry but does have some ancestry from wolves.

Golden jackals can also crossbreed with dogs, and it’s possible that domestic dogs have a bit ancestry from this animal. Evidence for this ancestry has not yet been discovered. Only the Sulimov dogs, which are recent intentionally bred golden jackal/dog hybrids, have been proven to have golden jackal.

Ethiopian wolves can also cross with dogs, and hybridization with domestic dogs in the Bale Mountains has been considered a major threat to their continued survival.

Other than those animals I’ve just listed, there is no proof other than anecdote and lore that these dogs have crossed with any other wild dogs. There is no genetic evidence of a dog and red fox hybrid, though there were always alleged ones. There is no evidence of African wild dogs crossbreeding with any dogs, except from breed lore from Rhodesian ridgebacks and basenjis, and there is no evidence other than unsubstantiated claims that black-backed and side-striped jackals have ever hybridized with dogs.

There is a breed origin story for a breed from Thailand called the Bangkaew dog that claims dhole ancestry. Supposedly, they are derived from a bitch that got impregnated by dhole in the forest. There were no other domestic dogs around, so it had to have been a wild dog.

I think that golden jackals are a much more likely wild ancestor of this dog, if it does indeed have blood from another species. However, as far as I know, no one has looked for the genes of either dholes or golden jackals in this breed.

Except for dogs that were intentionally bred to coyotes or golden jackals, there is no evidence that species other than the wolf have contributed to domestic dogs.

There are always stories about different wild dogs crossing with domestic ones.

However, there has been no evidence of dogs crossing with anything other than the species I’ve listed here. All the rest are nothing more than stories, folk tales, and speculation.

I think one reason why people hold onto the hope that dogs are derived from a wide range of species is they secretly want to vindicate Konrad Lorenz and Charles Darwin, who may have been right about many things.

But they were wrong about the ancestry of the domestic dog.

Dogs, like it or not, are domesticated wolves that have some weird features in their DNA that make them very easy to mold into bizarre shapes through selective breeding.

They did not derive from hybrids of several dozen wild species.

Coren is simply wrong here, and I don’t know why he keeps makingthese claims. He made this same claim in The Intelligence of Dogs, when the genetic literature wasn’t as clear as it is now,and in How to Speak Dog.  Every genetic study shows that dogs are derived from wolves, and modern dog lineages are likely derived primarily from the wolves of the Middle East. No matter how many times Coren or anyone else wants to claim that dogs are derived from many species, the claim will be still be false. And it’s even worse that he makes claims that dogs are derived from species with which they cannot even cross.

There are so many errors in that first slide that I couldn’t get to the rest.

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This is an Arabian wolf (Canis lupus arabs). It is a wolf that is very similar to a dingo.

As regular readers of this blog know, I am generally opposed to splitting up species, unless  a very, very good reason is given.

For example, I can see that coyotes, golden jackals, and wolves are different species. Although capable of interbreeding and producing fertile offspring, these animals normally don’t hybridize. The evidence is clear that they split from common ancestors millions of years ago, and they maintain very clearly different ecological niches.

But when you start talking wolves and dogs, I see far fewer differences, especially when one considers how diverse wild wolves are and have been through their evolutionary history. It is intellectually dishonest and misleading to base all comparisons between wolves and dogs by using the big game hunting wolves from Alaska and Northern Canada as the wolf from which all analogies are made.

Those wolves are actually quite specialized– every bit as much specialized as a border collie, a golden retriever, or a pointer.

Keep mind that in the Middle East, there are very dog-like wolves. The subspecies is called Canis lupus arabs. Except for color, it very strongly resembles the dingo of Australia, which is often considered a “primitive” form of domestic. (I consider it a domestic dog that has fully returned to the pack-hunting wolf culture and ecological niche).

As has recently been revealed, dogs were originally domesticated in the Middle East, and it is likely that if we want to make comparisons, we should be looking at C. l. arabs, not all of these moose and muskox hunters. No serious authority considers C.l. arabs a distinct species, so I am not about to consider the validity of Canis familiaris.

It’s a silly name.  The differences between dogs and any wolves are no more extreme than the differences between Eurasian wild boar and domestic pigs or between domestic cattle and the extinct aurochsen.  We don’t consider domestic mallards to be different from wild ones, even though we have call ducks and Rouen ducks that are very different from the original wild form.

I think it’s just that we still have mental blocks about wolves that we cannot accept that they might be the same species as the creature with which we share our homes. A wolf is a wild thing that cannot be controlled, but a dog, well, a dog is something that can be controlled.  It’s just a degenerate wolf that evolved to eat human feces and garbage.

There are certain arguments that need to be considered when thinking of where dogs and wolves fit together. Dog and wolf are not the same as wolf and coyote and wolf and golden jackal.

Dogs did not split from wolves millions of years ago. It was a much later split, and the split has not been complete.  The black coloration in wolves has been traced to genes that originated in domestic dogs.  I have found extensive historical records of dogs and wolves mating on the North American frontier. Essentially, without persecution to distort wolf behavior and genetics and without the presence of other domestic animals that require people to protect them from wolves, dogs and wolves are more than willing to get together.

But what about ecology? Don’t dogs and wolves have different ecological niches that make them separate species? That is also not a particularly convincing argument.

In the case of the dingo, these animals have returned to the wolf culture and ecological niche. They hunt large game in packs and act the top predator in their native country. Wolves in Italy might as well be dogs, because they live exactly as stray dogs do throughout the world. They don’t hunt much. Prey simply isn’t around, so they move into garbage dumps to find food. That is exactly the same ecological niche we see in most free-roaming domestic dogs.

Dogs and wolves are capable of adapting their cultures to the ecology of their particular situations. Within their genome is an ability to adapt their body types very to fit their particular situation. Wolves that hunt moose get very large. Their jaws become very powerful.  Wolves that hunt mostly small game never develop those traits. Their jaws are weaker, and they learn how to forage on their own, as is the case in the aforementioned Arabian wolves.

We underestimate the ability of C. lupus to adapt its behavior and its physical traits at our own peril. It is something we cannot understand. We are not that physically different from each other, so we assume that other species are similar. It’s very hard for some to accept that Pekingeses and Arctic wolves are part of the same species.

It’s not very hard for me.

And when I think about it, I am even more deeply amazing at the species with which we share our lives.

What has been written above is an intellectual exercise. Taxonomic debates and analysis often are, and when we consider the exact taxonomy of the genus Canis, debate is automatically going to be in the offing.

But this debate has certain practical realities, which can actually harm conservation efforts.

Wolves are a good example. Not only are dogs often considered a separate species, but several wolves are considered distinct enough to have their own species status.

The red wolf is the most famous one. Too much has been written on that particular animal, so I’m not going to waste a lot of time on that one. I will say that I am of the view that it is the result of hybridization between C. lupus and Canis latrans. Some evidence suggests that this hybridization happened in recent times. However, there are theories that they represent an ancient hybrid or are some form of ancient wolf that evolved solely in North America.

I’m not going to go into this one, but I do know red wolves behave like C. lupus and not like coyotes. However, we are spending lots of time and money trying to keep red wolves from mating with coyotes.

Just out of tradition, I consider them to be part of C. lupus, along with C. lupus lycaon, the timber wolf or Eastern Canadian wolf. Some authorities believe that these animals are the result of hybridizaton between C. lupus and the coyote. Others consider them to be the northern population of the red wolf, if they also count the red wolf as a distinct species.

These are probably the best known wolves with undetermined taxonomy, but just a few years ago, it was decided that the Indian wolf (C.l. pallipes) and the Himalayan wolf (C. l. himalayensis) are also distinct species.

Considering these animals to be distinct species does have some practical political benefits. After all, it is easy to get people worked up about protecting a distinct species than a mere subspecies.  Legally, it is called the Endangered Species Act, not the Endangered Species and Subspecies Act, although conservationists do try to preserve the distinct subspecies for a particular ecosystem.

And maybe that is a good thing that we can get attention focused on preserving a population of unique animals.

However, there are situations in which splitting up a species is nothing more than a good way to kill it.

I am reminded of the recent finding that has led some to count the northern white rhino as a distinct species from the southern white rhino. The southern white is a relatively healthy species. If a species of rhinoceros is going last through the next few centuries, it will be this one. The northern white rhino is extinct in the wild, and only a few individuals exist at the San Diego Wild Animal Park and a zoo in the Czech Republic.

(Four of the six Czech rhinos have since been sent to the Ol Pjejeta Conservancy in Kenya, where they could be very useful in preserving their species. I have not heard whether they will be allowed to interbreed with southern white rhinos or not. I hope that it at least gets considered. You can support Ol Pejeta’s efforts here.  )

It could possibly be preserved through some cross-breeding, and such cross-breeding has been employed in the past. I believe the Przewalski’s horse was essentially save through the influx of some domestic horse blood. However, Przewalski’s horse is now regarded as a subspecies of the wild horse from which the domestic horse descends– even though it has a different chromosome number.

The reason why we spend so much money preserving red wolves from coyotes is that we can’t conserve hybrids. People also worry about dingoes crossing with Western domestic dogs all the the time. There is an obsession with trying to find and preserve pure dingoes.

In weird way, this strarts to resemble something else.

Something I’ve always believed was more than a bit detrimental to domestic animals.

It is this desire to have purity for purity’s sake.

If we decide that some animals are distinct species and can never be crossbred, then we’ve essentially doomed them to extinction.

Of course, there are legal reasons for doing so. Blood purity problems plagued some of introductions. When a study came out about the hybrid origins of the red wolf,  various wolf haters called foul.  That is one reason why the Ghost Ranch Mexican wolves were deemed unsuitable for reintroduction. The possible taint of their bloodline meant that the wolf haters would be empowered.

I know that conservationist are much more concered with genetic diversity than breeders of purebred domestic animals. That’s an obvious difference between the two groups.

However, it is possible that splitting up species because of some unique genetic characteristic could have disastrous genetic consequences.

I can see that possibility that all of this splitting actually winds up creating situations that are akin to breeds of domestic dog. That is something that species with very limited populations really don’t need.

And it would be worse than the situations that exist within the closed registry system in domestic dogs. It is one thing to breed a golden retriever to a poodle. It is quite another to breed two species together that we have decided must be distinct enough to be different species.

Evolution has never embraced blood purity. That is a human construct. Nature has shown us that time and again, species have evolved through the influx of genes from another.

Including ours.

There is some evidence that after our ancestors split from the ancestors of the chimps and bonobos that our ancestors interbred with their ancestors again.

Species often are able to adapt and develop sustainable gene pools when natural gene flows are allowed to happen.

Such an idea is very hard for people to understand.

We like clear differences between ideas and concepts.

But in nature things are often nuanced and gray. The stark differences we expect and need for our understanding often aren’t there. Things that look clear  and distinct are actually quite smudged.

And when we try to create distinctions, we wind up with some real problems.

Our brains like distinctions, but the world is not as distinct as we like it.

How we answer these questions ultimately will affect how we create conservation strategies.

We can use the knowledge we have to preserve as much biodiversity as we can.

It may mean that we turn off that part in our brains that wants complete and total distinctions for the sake of preserving genetic diversity of certain species.

It does us no good to do to endangered species what we have done to our domestic animals.

It’s not good for our dogs, and it could be a killer for so many species.

This is a tendency that should be checked–or at the very least, kept in perspective.

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c. lupus familiaris

Okay, I know I’ve touched on this before.

But I think I’ll go ahead with another post on this topic.

Dogs are wolves. They differ at most 0.2 percent from wild wolves in their MtDNA sequence. I needed to italicize that “at most” because it is very common to see it written that dogs differ 0.2 percent from their MtDNA sequence.  That means the maximal difference between dogs and wolves in their MtDNA sequence is 0.2 percent.

Historically, they did interbreed quite a bit. Accounts exist of settlers on the American frontier using bitches in heat to bring in the dog wolves, which would mate with them. Because dogs remain tied together after mating, it was easy to dispatch the copulating wolf with an axe.

This interbreeding has caused a great deal of genetic pollution in the European wolf population, leading to unusually colored wolves and wolves with dewclaws on the hind legs. We also have evidence that the black coloration in wolves in North America came from cross-breeding with dogs.

Now, a dog is a wolf that has adapted to a particular environment. It is just like the Arabian wolf is adapted to the deserts and the Arctic wolf is adapted to the frigid wastes. Neither animal could live in the other’s environment, yet they are of the same species.

A dog is simply a wolf that can live safely with people. It can read people better than the wolf can, and as a result, it is better able to learn from people than virtually any other non-primate species.

To me, it makes sense to call dogs Canis lupus familiaris. It makes as much sense as calling the Arabian wolf Canis lupus arabs or the Arctic wolf Canis lupus arctos.

Now, there are three groups of people who don’t like to call dogs wolves.

One of these groups are the people who hate wolves and like to talk about the negative aspects of their behaviors. They don’t want them to be associated with the domestic dog, an animal that most people like.

Another group is the people who don’t want people owning wolves. If dogs and wolves are the same species, shouldn’t we be able to keep a wolf like a dog? The answer is no.  Wolves are too reactive and  powerful for the average person to own. Their predatory behavior can be easily stimulated, which means that children and other domestic animals could be at risk from these animals.

However, I should also say that there are  domestic dog for which this same caveat applies. And there are wolves that are very dog-like and not even remotely reactive or nervous (like this one.)  But most dogs behave like dogs, and most wolves behave like wolves.

The other group that would rather I not call dogs wolves are the positive reinforcement dog trainers. After all, the training methods they hate are based upon an assumption that dogs are wolves, and wolves form packs that are ruled by a tyrannical alpha. If dogs are not wolves, then their behavior is very different, and thus, we can get away with training them using other methods.

Now, I do have an answer for this one.

The studies that determined that wolves live in packs like this have their roots in Switzerland. Rudolf Schenkel studied captive wolf packs in the Basel Zoo in the middle part of the twentieth century. These wolves were unrelated animals and were kept in close confinement together. To prevent fights, they formed a really strict hierarchy, and Schenkel assumed that this type of pack behavior was indicative of how wolves behaved in the wild.

Of course, we have since found out that wolf packs in the wild are much more libertarian organizations. They are nothing more than family groups, and if one wolf gets ticked off at another, it disperses. Indeed, virtually all wolves disperse from their natal packs to form their own families.

But even these pack forming behaviors are not absolute with wolves. Sometimes they form super packs in which several breeding pairs and their offspring live as a single group. And some wolves never form packs larger than the mated pair, particularly in the Arabian and Indian wolf subspecies.

Moreover, the most studied wolves are the big game hunting wolves that live in northern Eurasia or northern North America. These are actually quite specialized wolves.

To assume that these wolves can tell us anything about dog behavior is a bit of a stretch, but what it says to the positive reinforcement crowd is that wolves have always had variable behavior in the wild. Dogs are not set in stone to follow leaders any more than wolves are. Dogs and wolves are both intelligent animals that have always adjusted their behavior to fit their circumstances. That is why the species was so successful. Indeed, it still is successful, because some individuals figured out how to live with the naked apes that would later claim dominion over the whole planet.

I do recognize dogs to be a subspecies of wolf. However, I am not denying that there are differences. However, this species is already diverse in terms of behavior and phenotype in its wild form. Shouldn’t we also expect a lot of diversity in its domesticated form?

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