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Archive for the ‘dog domestication’ Category

gordon buchanan wolf

Gordon Buchanan with a wild arctic wolf on Ellsmere. Photo by the BBC.

For really long time, the mystery of human bipedalism vexed us. Our closest relatives, the chimpanzees and the bonobos, are all knuckle-walking apes, and there was an assumption that the common ancestor of all three species was a knuckle-walker. At some point, the lineage that led to our species rose up on its hind legs, perhaps to make it easier to gaze over tall grass, and we became bipedal.

The current thinking, though, is that humans never derived from any knuckle-walking ape. Instead, the common ancestor of humans, chimps, and bonobos was likely a brachiator.  The modern brachiators are the gibbons and siamangs, the so-called “lesser apes.” These animals are highly arboreal, and because they lack tails, they rely upon their long limbs to move swiftly through the trees. When on the ground, brachiators walk bipedally, swinging their long arms to the side for balance.

Humans evolved bipedalism from these brachiators, while the chimps and bonobos became knuckle-walkers. In this scenario, humans never were knuckle-walkers, and it is misleading to think that humans rose up on our hind-legs from creatures that moved like chimpanzees.

What does this have to do with dogs?

Well, there have been quite a few studies that have compared dogs and wolves that have been imprinted on humans from an early age in hopes that we might figure out the domestication process from studying how tamed wolves behave when compared to domestic dogs.

These are interesting studies, but I think they oversell what they can answer.

It should be of no secret that I am very much a skeptic of the Raymond Coppinger model of dog domestication. His model contends that dogs necessarily evolved from scavenging wolves that gradually evolved not to fear people and then became village dogs. Our specialized breeds are thus derived from village dogs that were later selectively bred.

Coppinger thought that wolves were just too hard to domestic without this scavenger-to-village dog step that lies between truly wild wolves and their evolution to domestic dogs.

Modern wolves are hard to tame. They must be bottle-raised from an insanely early age.  Coppinger thought that it would be impossible for people living during the Pleistocene to provide that kind of care for young wolf pups.

Like the people who assumed that humans evolved from knuckle-walkers, Coppinger assumed that wolves that exist today are good models for what wolves were like during the Pleistocene. These wolves are reactive and nervous to the point of being paranoid. It is well-known that many wolves won’t even attempt to den near human settlements, and if they catch wind of humans, they soon leave.

These animals would not be easily tamed by anyone, much less people living with Stone Age hunter-gatherer technology.

I generally accepted his arguments, and in the early days of this site, I largely parroted them.

A few years ago, I was watching a documentary about the tigers of the Sundarbans, a vast mangrove forest that straddles the border between India and Bangladesh. These tigers are notorious for their man-eating behavior, and there have been many theories posited about why these tigers so readily hunt man. Among these is the argument that the Sundarbans tigers drink so much salt in their water intake that it destroys their kidneys, which disables them and makes them more likely to hunt man.

But the documentary contended that the real reason these tigers are more likely to hunt man is that all other tigers descend from populations where humans have hunted them heavily. In British India, tiger hunting was a popular activity among the colonial administrators, and this intensive hunting cause tiger populations to drop.  This hunting left behind only tigers that had some genetic basis to fear man more, and thus, man-eating tigers are exceedinlg rare now.

The Sundarbans never received this hunting pressure, so the tigers left behind had the same innate tendencies to hunt humans that the ancestral tiger population possessed.

I found this argument utterly intriguing, and I began to weigh it against what I knew about wolves. Wolves across their range have experienced even more persecution than tigers have.  In North America, we have four hundred years of humans coming up with more and more creative ways to kill them. In Eurasia, this persecution has gone on for thousands of years.

The persecution of wolves surely has had some effect in how wolves behave, including their innate tendency to accept humans and other novel stimuli in their environment.

Wolves are often so fearful that they won’t cross roads.  They just avoid people at all costs, and it just seems that this is an animal that we couldn’t possibly domesticate or even habituate to our presence.

This has led some people to suggest that dogs aren’t derived from wolves, but some Canis x creature that is related to dogs and wolves, but it is ancestral to the former but not the latter.

Genome comparisons have shown that such claims really don’t work. Dogs are derived from an archaic wolf population, and in this way, they are sort of genetic living fossils, holding the genomes of a Pleistocene wolves that no longer exist. But these wolves that became dogs were still part of Canis lupus, and thus, we have to maintain dogs as part of Canis lupus as well in order to retain the monophyly of the species.

Except for dogs that have modern wolf ancestry, no dog is actually derived from a wolf population that exists today.

And the wolf populations that exist today just seem so hard to tame and work with that it makes sense then to consider the need for Coppinger’s scavenging wolf-to-village dog stage between wild wolves and modern dogs.

The thing is, these studies using modern wolves are only using wolves that are derived from these heavily persecuted populations, and it is very unlikely that these animals are representative of the wolves that lived during the Pleistocene.

We know that when wild dogs have never experienced human hunting, they are intensely curious about us. Timothy Treadwell had a pack of tame red foxes that followed him around like dogs while he was off communing with the brown bears. Darwin killed the fox that was named after him by sneaking up on one and hitting it with a geological hammer.

Lewis and Clark came onto the American prairies where there were vast hordes of wolves lying about.  The wolves had no fear of people, and one wolf was actually killed when it was enticed in with meat and speared in the head with a spontoon.

After these wolves experienced the persecution of Western man, the only wolves left in the populations were those that were extremely wary and nervous.

In fact, the only wolves that exist now that have never experienced widespread persecution by man are the white wolves that live in the Canadian High Arctic.

I’ve had the pleasure of watching two documentaries about these wolves. The first was by Jim Brandenburg.  Brandenburg and L. David Mech spent a summer living with and filming wolves on Ellesmere.  These wolves showed no fear of them, and they allowed them to observe their natural behavior in the wild, including allowing them near their den sites.

Virtually the same documentary was recently made by Gordon Buchanan of the BBC. Buchanan came to Ellesmere and became accepted by a wolf pack, which eventually trusted him enough to allow him to babysit their pups while the adults hunted.

These wolves hunt arctic hare and muskox. They live hard lives, but because they have no real history with man, they are oddly curious and trusting of people.

It seems to me that these wolves are much more like those described by Lewis and Clark, and they are likely to have behaved much like the ancient Pleistocene wolves did. They had never undergone extensive persecution by man, and thus, they were probably quite curious about man.

If these ancient wolves were more like the Ellesmere wolves, then it seems domestication would have been a pretty easy process. In fact, it appears to me that it is so easy to have happened that the struggle would have been preventing it from happening in the first place.

So if these High Arctic wolves are a better model for the ancient wolves that led to dogs, why aren’t they included in the studies?

Well, these wolves are hard to access, and what is more, because they represent such a special population, it might not be wise to remove any of these wolves from the wild.

So the socialized and imprinted wolf pup studies really can’t be performed on them.

But we could still get DNA samples from them and compare their behavior-linked genes to those of dogs and wolves from persecuted populations.

All these other studies are ever going to do is tell you the difference between dogs and certain wolves from persecuted populations. They aren’t really going to tell you the full story of why dogs came to behave differently from wolves.

So for the sake of science, we need to understand that evolution through artificial selection has affected wolves as well as dogs. Dogs have been bred to be close to man. Wolves have been selected through our persecution to be extremely fearful and reactive.

So as interesting as these studies are, they have a big limitation, and the assumption that these wolves represent what ancient wolves were like is major methodological problem.

 

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loose skinned arctic fox

The animal above is a super-sized blue phase arctic fox that is of a type being bred in Finland. The exposed haw is actually the result of being bred for super loose skin, a trait that those in the dog welfare community know very well. “Typy” shar pei and Neapolitan mastiffs are well-known sufferers from loose skin problems, but even a in breed that isn’t as exaggerated, like Clumber spaniels, this loose skin can lead to all sorts of eye infections.

This is a full-body shot of the Neapolitan arctic fox:

wrinkled fox

Why are arctic foxes being bred with such loose skin?

Well, that loose skin actually makes for a larger pelt and a larger pelt goes for higher price.  In nature, arctic foxes are quite small, much smaller than Boreal red fox subspecies, but the arctic fox in its winter fur is a much more valuable animal.

Both red and arctic foxes breed well in captivity, and they have been farmed extensively for their pelts. Captive red foxes come in many colors now, but the naturally-occurring silver phase was once the staple of fox pelt market. The arctic fox, especially its blue phase, is also quite valuable, but the smaller pelts mean they cannot compete with the silver phase reds.

These Finnish breeders have begun to produce large blue arctic foxes, some of which weigh 20 kg, and have very loose skin in order to make a much more profitable strain of arctic fox.

This development has several moral and ethical questions, as well as being something that those of us curious about dog domestication and evolution might find intriguing.

I should note that I am not anti-fur. I come from a long line of fur trappers, including my own paternal grandfather who used to trap red foxes to fund his union activities. He knew more about red foxes than anyone I’ve ever personally known, and he had a great appreciation for the species.

For some, the fact that these animals are being bred for fur is going to be the biggest ethical problem, but for me, it is the exaggeration in conformation that causes me greater worry.  When these animals are killed for their fur, it is done humanely. Finland is a leader in the humane treatment of animals, and killing fur-bearers on farms in a cruel fashion would not be allowed.  The standard practice is for the animal to be rendered unconscious, then electrocuted. (I don’t want to get into a long, drawn-out debate about these, because there are places where this practice isn’t followed. Finland isn’t one of them. )

But these foxes spent their entire lives with loose eyelids and a bulky conformation that puts an exorbitant amount of stress on their joints, and this truly is a welfare issue.

I see this as the main welfare issue of domestic dogs in the West. We’ve bred domestic dogs with such exaggerated conformation that we’re ultimately harming them, and the funny thing is these animal welfare sites that post shocking animal cruelty videos and images also generate web traffic with videos of cute little bulldogs and pugs with such shortened muzzles that they cannot breathe or cool themselves properly.

I find these loose-skinned arctic foxes appalling, in every way I find an extreme shar pei appalling.

And here I can agree with the animal rights activist. This is wrong.

But at the same time, my curious, scientific mind is intrigued. Fur farmed foxes are sort of parallel dog domestications.  Much has been written about the Belyaev fur farm experiments and what they might say about how dogs were domesticated, but the truth is virtually every fur farm breeding program for the various red and arctic fox phases is an experiment that could reveal some secrets about dog domestication.

It is amazing that we can selectively breed arctic foxes to reach the size of coyotes, and it is even more amazing that we can select for the loose skin in arctic foxes that we actively breed for in certain purebred dogs.

It would be interesting to get full-genome comparisons on these “monster foxes” and more typical arctic foxes.  Maybe the genetics are similar between these foxes and the super-sized and loose skinned domestic dog breeds we have produced.

If we are going to breed animals for agricultural purposes, we are going to have to do it humanely. I am certain the Finnish breeders of these foxes believe they have done a great agricultural improvement in much the same way their intellectual forebears in England in the eighteenth and early nineteenth centuries bred massive swine and beef cattle that could barely walk on their own hooves.

So yes, we have an ethical issue with these foxes, just as we have an ethical issue with the continued breeding of dogs with exessive loose skin and exposed haws.

 

 

 

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new guinea dingo

One of the most annoying things about “dog people” is the constant jockeying for the prize of the “most ancient breed of dog.”  If you watch Westminster on television, I would say a third of the breeds are described as “ancient.”

Most of them aren’t that old, and even if they do resemble ancient forms of domestic dog, the modern day representative often has very little genetic connection to them.

So it was with jaundiced eyes when I saw the latest headline that “The world’s rarest and most ancient dog was discovered in the wild.”  The headline is clickbait, of course, because most people don’t have a clue about what was actually found.

Some camera traps caught images of a type of dingo called the “New Guinea Highland Dog,” which is a new name for the “New Guinea Singing Dog.”  It is a dingo that lives a semi-feral existence in the highlands of New Guinea. Note that I said “semi-feral,” because different indigenous groups in New Guinea have used these dogs and their descendants for hunting.  It lives in the wild, but it can be tamed.

Genetically, these animals are not vastly different from Australian dingoes, which lived in much the same way.  They could breed in the wild, but indigenous people used them to hunt things like tree kangaroos.

These dogs exist where there are no wolves and are found in cultures that are mostly involved in hunter-gatherer societies. These animals might give us a window into how hunter-gatherer people in the Paleolithic may have related toward wolves and perhaps give us an insight onto how domestication may have occurred.

But the problem with these dogs is that there are fantastical claims about them. When someone says this is “the most ancient breed of dog” one needs to understand something. The most complete genetic studies we have on dogs have revealed that this type of thinking is quite flawed. One of the big problems is that no domestic dog is more closely related to wolves than any other. The only exception are dogs that have actual modern wolf ancestry.

Dogs are derived from an extinct population of wolves, and yes, a recent genome comparison study says we have to call this ancestor “a wolf” if we are to adhere to cladistic classification.  The reason is that dogs split off from Eurasian wolves at about the same time Eurasian wolves split from North American wolves.

genome comparis fan wolves and dogs

Arbitrarily declaring dogs and dingoes a species makes the entire Canis lupus species paraphyletic, according to Fan et al.

Dingoes are commonly used in genetic studies about dogs and wolves. When compared to a large number of samples of different breeds and different wolves, they almost always group with East Asian domestic dogs, as this dingo did with a Chinese street dog.

Another study, which found initially reported dogs originating the Middle East (but has since been retracted in light of more recent evidence), also found that dingoes fit with East Asian domestic dogs.

dingoes fit with domestic dogs wayne

It is well-known that New Guinea dingo-type dogs can be recognized as dingoes using a genetic test that looks for only certain dingo markers.

So the animal that was found in the New Guinea Highlands is a dingo, and a dingo is an East Asian domestic dog that has gone feral.

Now, about the question of this dog being “the most ancient.”

One of the problems with saying a breed is the most ancient, as I pointed out before,  is that no breed of dog is more close to modern wolves than any other, and the other major problem with saying a breed is ancient using genetic studies is that many of these so-called “ancient breeds” are actually just populations of domestic dog that have been isolated from the main swarm of dogs. This gives a “breed-like” isolation that confers upon it some antiquity that really doesn’t exist.

Thus, we really can’t say that a breed is the “most ancient,” even with genetic studies.

What I think is more interesting in regard to dingoes and New Guinea singing dogs is that they represent a different permutation of domestication than the bulk of domestic dogs.

Domestication is a cultural process as well as biological. The vast majority of dogs in the world today are street and village dogs, which are very easily tamed if captured at the right age. This is the permutation of dog domestication that arose after the Neolithic Revolution, and it is still the rule when dealing with societies that have not engaged in extensive selective breeding for working characteristics in domestic dogs.  We also have a permutation in which free-roaming and freely breeding livestock guardian dogs accompany herds across grazing lands. Any dogs that show aggression towards stock are driven off or killed. Another permutation, which is older than either of these two, are the people who actually rely upon their dogs as hunters. Here, I am thinking of the laikas of Russia, which are used to bay up boar and moose and tree gamebirds and furbearers in much the same way the Jōmon relied upon their hunting dogs for survival.

The Western permutation of dog domestication has been to breed many specialized dog breeds and types. We’ve selected for much higher levels of biddability in some of our dogs. We’ve bred out quite a bit of aggression and predatory behavior. We’ve accentuated certain predatory behaviors, like pointing and retrieving, and we’ve produced dogs that look you right in the eye for approval.

Western dogs have been removed very much from wolves, and from our perspective, it looks like the dogs of different cultures are more ancient than our own. But that’s from our perspective. Our own Eurocentric perspective.

For example, the indigenous people of the Americas were very much involved in producing specialized dog breeds. The Salish bred their own wool dogs.  The Tahltan bear dog actually was used to hunt bears, even though it was quite small.  The hairless trait that exists in most hairless dogs actually originated in Pre-Columbian Mexico.

The truth is people all over the world have produced dog breeds and types that are distinct. The various forms of dingo that exist in Australasia are exactly the sort of dogs that would occur in hunter-gatherer societies that were not engaged in the selective breeding of working animals. Instead, they are societies that relied upon feral dogs to provide their own hunting dogs, which often reverted back to the feral existence once they hit breeding age.

This is not the permutation of Western dog domestication at all, and because it resembles the ancient way man may have related to wolves, a lot gets read into these dogs.

These dogs aren’t more or less ancient than any other dog on the planet, but they are dogs that give us a glimpse of what might have been.

That is the amazing story.

But, of course, dog people can’t leave an amazing story to be told on its own, so claims about these dogs are made that simply aren’t backed up by serious inquiry and scholarship.

Unfortunately, we’re always going to be dealing with these sorts of clickbait stories about ancient feral dogs, but that’s not what the genetic studies are revealing. And it is quite sad that we’re still dealing with the erroneous Canis hallstromi classification for the New Guinea dingo, as well as its attendant “dogs are not wolves” hypothesis, which has been as thoroughly debunked as the “birds are not dinosaurs” hypothesis.

So it is interesting that the New Guinea dingo still roams in the Highlands,  but I wish peole would be very careful of clickbait canid taxonomy.

 

 

 

 

 

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chow-chow

Dog breed origins are often shrouded in a “creation myth.”  If you ever read an all-breed dog book, the official breed origins come across as awfully fanciful. Virtually every breed is regarded as ancient or derived from some private stock belonging to some notable:  Afghan hounds were the dogs Noah took on the Ark.  Beagles appear on the Bayeux Tapestry. Pharaoh hounds were the hunting  dogs of the Ancient Egyptian dynasties.

These stories posit the breed as being part of something deep in the past and maintaining the breeds is magnified as a way of paying homage to the past.

Some breeds are, however, pretty old, or at least genetically distinct from the rest of dogdom to be seen as something unique. Chow chows are a good example. They retain a lot of unique, primitive characters, and as East Asian primitive dogs, they may be among the oldest of strains still in existence.

Konrad Lorenz deeply admired the breed’s wolf-like attributes, believing they represented the best of the so-called “Lupus dogs.” Lorenz believed that most dogs were actually the descendants of golden jackals, and the dogs were friendly to most people and easily broken to fit the will of man. These were the “Aureus dogs.” But the dogs that were more aloof and more independent of the wishes of their masters were seen as the direct descendants of wolves. Lorenz preferred this type of dog, and he kept many chows and chow crosses in crosses as his own personal dogs and “study subjects.”

Lorenz later rejected the dichotomy between the jackal and wolf dogs, but the idea is still worth exploring. What Lorenz actually discovered was a profound division that exists in domestic dogs:  the primitive versus the derived.

In terms of evolution, an organism is considered primitive if it retains characters and behavior that are very like the ancestral form.  For example, lemurs are considered more primitive than other primates because they have the long muzzles and wet noses of the ancestral primates.

Primitive dogs are those that retain many features in common with the wolf. These features include erect ears, pointed muzzles, howling rather than barking, bitches having only one heat cycle per year,  pair-bonding behavior, and general tendency not to be obedient.  Many primitive dogs bond with only a single person, and in the most extreme cases, allow only that person to touch them.

Lots of “Nordic” breeds fall into this category, but this list also includes many of the drop-eared sighthounds from Central Asia, the Middle East, North Africa, and the Indian Subcontinent. It also includes many of the village dogs from undeveloped countries, as well as the semi-domesticated pariah dogs and dingoes.

The chow chow sort of fit between both Nordic breed type and the village dog type.  It has many of the features of the Nordic breeds– curled tail and prick ears– but it also has had a long history as a village dog in China, where it had periods in which it freely bred.

One would think that chow chow fanciers would be into celebrating their dogs as primitives, like owning something between wild and domestic.

But dog people being dog people are more than willing to add embellishments.

Westerners have done a lot to add to the bear-like features of the chow chow, which Konrad Lorenz actually castigated.

However, dog breeders will often go to great lengths to justify breeding decisions, including putting out absolute science fiction as scientific fact.

A few years ago, I heard an acquaintance mention that a well-educated chow owner she knew firmly believed that chow chow were derived from bears.

I laughed at it.  I did not think there was a serious discussion that chow chows were derived from bears.

And then I received notice of this website, which purports to have the full history of the chow chow. The history begins as follows:

It´s assumed that during the Miocene period (between 28 to 12 million years back), the evolution of the Hemicyon, an intermediary between the Cynoelesmus [sic], “father” of all the canine ones, and the Daphoneus [sic] – from which the bears descend as we know them today, – originated the Simocyon, an animal that varied between a fox and a small bear that inhabited in the sub-Arctic regions Siberia and the Northwest of Mongolia and of which it is known had 44 teeth.

I don’t know where this actually comes from, but it is entirely in ignorance of what we now know about the evolution of bears and dogs.  Dogs and bears are indeed closely related, but the division between the two is much deeper than the dates proposed here. Their most recent common ancestor was the ancestral stem-caniform miacid, which lived about 40 million years ago.  Most of the “ancestors” mention here are actually evolutionary dead ends that have little to do with modern bears or dogs.

First of all Hemicyon was not an intermediary between dogs and bears. The Hemicyon family was actually a branch of the bear lineage. Unlike the true bears, it was digitigrade and was probably a cursorial predator like wolves are today. The Hemicyon family lived between 11 and 17 million years ago, and it has left no living descendants.  That is, it is in no way an intermediary form between dogs and bears.

The author mentions “Cynoelesmus,” probably meaning Cynodesmus. My guess is this discrepancy comes from a poor cut-and-paste job, but although Cynodesmus was a primitive dog. It is not the ancestor of all living dogs. The ancestor of all living dogs was Leptocyon. Leptocyon was once considered part of Cynodesmus, but it is no longer.

The other two ancient creatures mentioned in the opening have nothing to do with bears or dogs.

“Daphoneus,” which refers to Daphoenus, a type of Amphicyonid. Amphicyonids were are really spectacular sister family to the canids, which had traits in common with both bears and dogs but really behaved more like big cats. This family has nothing to do with evolution of dogs, except that this is a sister lineage that went extinct.

Simocyon was actually something even a little bit cooler. It was not a dog. It was not a bear. It wasn’t even in the lineage of either family. Instead, it was a genus of leopard-sized animals much more closely related to the red panda. In case you were wondering, red pandas are not closely related to giant pandas. Giant pandas are actually a primitive form of bear. Red pandas are their own thing. Modern red pandas are the only species in their family known as Ailuridae. Millions of years ago, there were several species of red panda, and Simocyon was actually a large predatory red panda. Like the modern red panda, Simocyon had a thumb formed out of its sesamoid bone.  Giant pandas have this thumb, and it was thought to connect both modern species of panda.  Now, we know that the giant panda, which is a true bear, actually evolved its sesamoid thumb in parallel to the red panda. The red panda lineage evolved this trait so they could more easily climb in trees, while the giant panda evolved it to hold bamboo.

So that entire introduction to chow chow history is simply wrong. It may have been correct carnivoran paleontology at one point, but it also seems that the originators of this theory just went around looking for creatures that sounded like they might be fossil dogs that could be found in Asia.  “Cyon” does mean dog, but it doesn’t always refer to dogs in scientific names. Remember that there is a primitive whale the unfortunate name of “Basilosaurus,” which is in no way related to any lizard or dinosaur, and the raccoon family is called “Procyonids,” even though they aren’t that closely related to dogs.

Again, I don’t know why this theory is so popular, except that it can be used as a defense for breeding more and more bear-like features into chow chows than they had when they first came into the West. It’s also a way of making chows so much more super-special than the were before.

But it really makes chow fanciers look silly to anyone who has ever looked closely at carnivoran evolution.

It’s a fun story, but it’s not based in reality.

And when you get the paleontology this wrong, then virtually nothing of value can be trusted until the error is corrected.

Chows are cool as primitive dogs. They don’t need all the malarkey.

 

 

 

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015

I keep running into this female Eastern box turtle when I am out and about. She is usually out looking for a place to lay her eggs, and because I know that her particular subspecies could become threatened in the near future, I don’t even touch her.

At one time in my life, I would have taken her home. Most rural children in my part of the world collect box turtles during the early summer and try to make pets out of them.

The truth is that this subspecies, the Eastern box turtle (Terrapene carolina carolina), actually makes a terrible pet. They become deeply attached to their home range, and taking them from their home ranges stresses them so much that they become susceptible to disease and parasites.

The Eastern box turtle is a subspecies of the common North American box turtle, which used to range up into Eastern Canada as well as most of the Midwestern and Eastern US.  We know only about its range in Canada from remains that have been dated to the sixteenth century, but now it is experiencing lots of problems in its range in the US. In the neighboring state of Ohio, it is a “Species of Concern,” but it is still pretty common here. I’ve seen little, tiny hatchling box turtles that aren’t much bigger than a quarter, but these little turtles aren’t maturing many parts of their range.

So I don’t recommend that anyone keep pet Eastern box turtles, especially those from wild populations. Many states ban the practice now.

Even if you have a box turtle as a pet, it requires a large enclosure, a high protein diet, and relatively high humidity.

But not all box turtles subspecies have the same problem with attachment to their home ranges than the Eastern subspecies has.

In the South-Central US. there is another subspecies of the common North American box turtle, which is called the three-toed box turtle (Terrapene carolina triunguis). I first saw these turtles at a pet store in Vienna, West Virginia, and I was amazed at how much they looked like the native subspecies. The main difference was they were mostly chocolate-brown in color and had three-toes on their back feet.

three-toed box turtle

I didn’t know at the time, but these three-toed box turtles were being offered as pets simply because they were found to be much better suited to captivity than the Eastern subspecies. They still require the humidity, the large enclosure, and the high protein diet.

However, they aren’t as greatly stressed from being removed from their native ranges, and as a result they are much better able to adapt to captive conditions.

When a three-toed box turtle is released into my part of the world, they often cross with Eastern box turtles. I have often suspected that the Eastern one at the top of this page might be a hybrid, simply because she lacks the extensive yellow markings on the head.

But that could simply be a variation in the Eastern subspecies.

Whatever the story of these two box turtles is I think they can tell us a lot about how to think of wolves and dogs.

Modern wolves are very difficult to domesticate, and they make terrible pets. Dogs, of course, do very well in the human environment.

Just like the box turtles, there are minor morphological differences between wolves and the less exaggerated breeds of domestic dog.

And when given the opportunity, dogs and wolves exchange genes.

I do not know how much DNA Eastern and three-toed box turtles share. My guess is they share far less than dogs and wolves do, simply because dogs and wolves are a highly mobile, relatively large species and species with those characteristics tend to have less diversity as a species. Regional box turtle populations are going to show greater distinctiveness than a wolf or dog population when compared to the entire species.

My guess is that the split between the two subspecies happened earlier than the split between dogs and wolves, too. T

But it’s not controversial that Eastern and three-toed box turtles are just separate subspecies. However, saying the same about dogs and wolves tends to launch people. That’s because there are political and sociological reasons for classifying dogs as a separate species from the wolf, which you can’t say about the two subspecies of box turtle.

But if we’re willing to say that these two box turtles are part of a single species, what level of mental gymnastics are we willing to engage in to keep wolves and dogs separate species?

I know the answer to that question, I’m afraid.

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It’s very popular for people to deny dogs their proper classification according to molecular cladistics.

It’s popular because to accept that dogs are a type of wolf and actually belong to Canis lupus means that one has to deal with all sorts of political baggage that goes along with it.

Does it mean that Cesar Millan is right? Not at all.

Does it mean that I can go out and keep pet wolves? I wouldn’t recommend it.

But just because those two concepts are bogus doesn’t mean that the classification of dogs as part of Canis lupus is invalid.

This idea of dogs not being wolves was popular in the era of pre-cladistic classification. Cladistic classification is a way of organizing taxonomy to reflect evolutionary relationships. Paleontologists and anatomists spend hours classifying creatures using morphological characters, and there is a lot of debate, especially in paleontology, about how extinct organisms should be classified.

Currently, most taxonomists who use cladistic classification pay much more attention to molecular data. DNA tells us much more about common ancestry than we could ever get from bone or fossils. And yes, there are surprises.

We know now that dogs are nothing more than specialized offshoot of the Holarctic wolf. Canis lupus today exists in four lineages: the Holarctic wolf, the South Indian wolf, the Himalayan wolf, and the African wolf (which had previously been recognized as a form of golden jackal). We also know that dogs were domesticated in Palearctic somewhere, so they actually do derive from some form of Eurasian wolf.

This form is probably extinct, because the best nuclear DNA studies have shown that dogs are not derived from any extant wolf population.

If we are to adhere to cladistic classifiation, Canis familiaris is an invalid taxon.

So is Canis dingo. In fact, because dingoes fit within East Asian domestic dogs, the common scientific name Canis lupus dingo is also invalid. They are also Canis lupus familiaris, though definitely distinct ecomorph.

Some people get really worked up with this classification stuff, because the world of dogs inherently political. If you say a dog is a wolf, people jump to conclusions about some endorsement about feeding or training.

Politics be damned. Classifying organisms according to how they evolved is a much more important exercise than these tempests in a teapot that constantly swirl around the world of dogs.

I’m not saying that a golden retriever is the same thing as a large Alaskan wolf, but those two animals share more characters and more DNA than either shares with a coyote or a black walnut. If a golden retriever came in heat in the Alaskan bush and she ran into an unattached male wolf, they would breed and produce fertile offspring.

Indeed, many dog breeds have documented wolf ancestry. These include many arctic and boreal breeds like West Siberian laikas and Alaskan malamutes, but wolves have also been crossed into such unlupine breeds as Plott hounds, otterhounds, and griffon Nivernais.

Similarly, the black coloration in North American and Italian wolves originated from crossing with domestic dogs. It’s also not unusual for people to come across Italian wolves with dewclaws on the hind legs, which also is a diagnostic trait for crossbreeding.

When someone denies the phylogeny of domestic dogs, they usually do so rocking back on their heels as if they were somehow the most super-rational person in the world.  Only a fool would deny that a dog isn’t a wolf!

But it is these people who are in denial. Most of the ones I’ve seen either own little dogs that really don’t look or act much like wolves or they cannot think skeptically about Raymond Coppinger’s work.

Most people, I’ve discovered, have a very hard time thinking of organisms according to their clades. Part of that problem  is that it’s very hard to think of humanity as the last survivor what was once a diverse lineage that came out of same stock that gave us chimps and bonobos. If we were to adhere to cladistic classification, chimps and bonobos would have to be placed within our genus. We would either have to become part of Pan, or they would become part of Homo. The only reason this isn’t done is that this sort of classification would mess up the scientific names of all the transitional forms between our last common ancestor with chimps and bonobos and ourselves, and there actually are pretty big differences between the Australopithecines and Homo erectus.  Dogs and Holarctic wolves differ no more than 0.01 percent in their nuclear DNA sequences. Humans and chimps differ about 5 percent.

Of course, a dog is much more a wolf than a human is a chimpanzee. A dog is also much more a wolf than a human is the last common ape ancestor between humans and chimps. Dogs and wolves still exchange genes over the vast spaces of Eurasia and North America. They once did so far more often, when far more wolves lived near far more people and domestic dogs.

We live in a time when dogs are bred in closed registries, and too many dog people think of their favorite breeds as almost being distinct species unto themselves. Most dogs never see wolves. Most wolves never get to see free-roaming domestic dogs.

They could become separate species, but it would take a while. Even now, full reproductive isolation doesn’t exist in certain species in the genus Canis. Wolves mate with coyotes, which has caused some taxonomic wars with North American admixed canids like the so-called red wolf, and African wolves in Senegal have been known to breed with golden jackals.

Our species once existed with other human species. We could cross with neanderthals. We could cross with the Denisovan people. We are now alone, but dogs and wolves are still around with other species with which they can hybridize.

We are the species that does the classification, but we are the last survivors of our lineage. We used to think of Africans and indigenous Australians as distinct species from Caucasians. We did the same with people from Asia and indigenous Americans. We now know that, even though some of us are admixed with other extinct human species, we are all actually the same species and that the vast majority of our ancestry– no matter who we are– came from a single origin in East Africa.

We really aren’t that diverse. We’re really common, but when compared to chimps, we’re not that diverse at all.

But Canis lupus is a pretty diverse species, especially when you include African, South Indian, and Himalayan wolves to the species. Wolves are quite diverse in phenotype, ranging from 25-40-pound Arabian wolves that live on carrion and small game to 130-pound Alaskan wolves that live on moose. When you add domestic dogs to that classification, phenotypical diversity becomes even more explosive.

When you start thinking about wolves this way, they become something quite amazing. It’s really hard for us to think of pugs and arctic wolves as being the same species, but when you realize they are, it’s stunning what can happen through the forces of evolution through natural and artificial selection.

And when you put it into the context of the rest of life on this planet, it becomes humbling.

It all comes from these same processes.

That’s what amazed Charles Darwin.

And that’s what should amaze us.

So stop the cheap phylogeny denial.

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