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Archive for June, 2012

The Answer.

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All black wolves that have been examined in modern times have been found to be dominant blacks. The dominant black mutation first originated in domestic dogs and was transmitted through crossbreeding between wolves and dogs. However, there is at least one record of a wolf that was carrying recessive black.

Recessive black is most commonly found in German and Belgian shepherds. It can also be found in pulik, Samoyeds, schipperkes. Shetland sheepdogs, and the so-called “American Eskimo dog,” which is actually an American variant of the German spitz.

It’s one of two ways that a dog can be solid black, but it’s far less common than dominant black.

The mutation that causes dominant black originated either in dogs or the wolf population that became dogs, because the mutation is older in domestic dog populations than in wolves. This black coloration wasthen transmitted to Italian and New World wolves through cross-breeding with domestic dogs.  All wolves that have been examined in North America thus far have turned out to be dominant blacks, as have those in Italy.

However, there was at least one case of a wolf carrying recessive black in the literature.

The Soviet zoologist and dog expert N.A. Iljin carried out several experiments crossing various dogs with wolves. In 1941, he reported on the progeny of a male wolf that was bred to a female mongrel sheepdog.  In the first litter, there were black and “zonar gray” (wild wolf gray puppies). If the dog in question were a dominant black, then the entire litter would have been black, but getting gray puppies suggested a very different conclusion.

After breeding from the offspring for several generations, Iljin discovered that the black was being inherited as a recessive allele, which means the dog in question was a recessive black– and the wolf was a carrier!

Now, results of Iljin’s study have been used to show that wolves carried recessive black from the beginning.

However, since the time of Iljin’s work, no one has found a recessive black wolf.  The team of geneticists at UCLA have found only dominant black in wolves.

So it’s possible that this wolf was not actually “pure,” and at some point, one of its ancestors was a recessive black dog. I would not be surprised if someone had crossed a recessive black German shepherd into captive Russian wolves at some point. Iljin himself was very much into breeding German shepherds to wolves, and his studies on wolf and German shepherd morphology are pretty much classic literature for those interested in wolves and dogs.

So maybe recessive black did exist in certain Old World wolves from the beginning, but it’s just not been confirmed in the genetic literature in the same way that dominant black has.

I don’t know of another species besides Canis lupus that has two separate genetic variants for melanism. Coyotes have inherited dominant black from breeding with either dogs or wolves, and golden jackals and Ethiopian wolves could also inherit both types of melanism through similar hybridization.

So it’s very interesting that we have this one case of a wolf carrying recessive black, but we need more information to see where this color came from.

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Golden retriever fetching logs in Minnesota.

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Two dogs killing a deer in Ohio.

(Source for images)

I’ve noticed that dog people like to view their animals through reductionist paradigms.  It’s really an easy way of trying to make sense of what is really a complex matter:   the relationship between humans and dogs. The relationship between our two species is as complex as it is ancient, and because it has both complexity and antiquity, it is mysterious.

But in order to explain this relationship, paradigms have developed to explain why dogs and people like each other. Inherent in trying to understand this relationship is trying to understand what a dog actually is. We also try to figure out ways in which it differs from its wild ancestor, which should give us some understanding of what its innate nature actually is.

Sadly, trying to answer these questions has resulted in the development of reductionist paradigms, which often ignore evidence that disputes the essential assumptions of the paradigm.

Two really problematic reductionist pardigms have developed in recent years. Both are in response to each other, and both have very big problems when actually applied to understanding what dogs are.

The first of these is dogs is the one that says dogs are not wolves.  Dogs never form packs, they say.  They are never capable of cooperative hunting because they are perpetually wolf pups.

Usually, someone throws in some of Raymond Coppinger’s neoteny theories, which say that all dogs are simply juvenilized wolves and that Western working breeds are juvenilized only so they exhibit stunted predatory motor patterns. Pointers are stuck making stalking behavior. Herding dogs can only chase and stalk. Andd retrievers can only catch prey and bring it back. Because these dogs are juvenilized wolves, they can never exhibit wolf cooperative hunting behavior.

Much of the acceptance of this claim comes from a reaction to the crackpot variants of what is called “dominance theory.” Dominance within ethology is a very specific term that refers only to an animal getting “priority access to limited resources.” Unfortunately, dominance has become a catch-all for some pseudo-dog experts. Some of these people claim that virtually any time a dog doesn’t obey instantly it’s being “dominant” to you, and the best thing you should do is put him back in his place in the hierarchy.

This paradigm comes largely from observing unrelated wolves that were kept in enclosures together. Trying to make assessments about how dogs ought to behave through observing stressed out, reactive wolves is a fool’s errand. Dogs are very happy to be in captivity– which is exactly what you’d expect from them being the oldest domestic animal. They are also much more tolerant of strangers of their own species than virtually all wolves are. Wolves often kill other wolves that wander onto their territories, and if dogs were as aggressive with strangers of their own species as wolves are, dog parks would be an impossibility. Further, dogs bond with and learn from people much more easily than wolves do, so one cannot understand how dog “ought” to behave without trying to understand how they interact with people.

This one doesn’t try to make a claim that dogs are wolves. It merely assumes that because we have studies on wolves that show this behavior that we should be able to apply it to dog and human interactions.  This is not a good assumption.

Virtually everyone who has read the literature and has also spent time with lots of dogs rejects the crackpot dominance paradigm.

However, some people have replaced it with the other paradigm, which is just as problematic.

The biggest problem is that domestic dogs can learn to form packs and hunt, kill, and consume large prey.

Ask any sheep producer about the problem of packs of stray dogs.  They will tell you that sheep are quite vulnerable to attacks from wandering bands of domestic dogs. Some dogs get very good at hunting sheep together, and they often surplus kill, which means that a couple of dogs can wipe out an entire flock in pretty short order.

Secondly, I’ve heard a great many stories of dogs killing deer. My grandfather was a foxhound enthusiast in the 50’s, and every year, the local foxhound club held a field trial. They’d buy a permit from the state DNR, and they turn out 60 foxhounds into the woods. The dogs got scored for scenting the fox and running it close for a long distance.

But a great many dogs were disposed toward deer chasing.  When you turn out that many dogs, it doesn’t take much encouragement for them to take off after a deer. Out of that 60 dogs, there might be 20 that take off after deer, and of these, about half will cooperatively run down the deer in exactly the same manner as one would expect from wolves.

He told me that one year, the dogs killed something like 3 or 4 deer. One they ran nearly ten miles before they killed it. They just so happened to have dropped the deer in the middle of a pasture, and the farmer who lived there was quite upset. There were about a half-dozen foxhounds eating on a deer carcass in his pasture, and he wanted the DNR to shoot the dogs. The local conservation officer said that he would not. The foxhound club had paid for the permit, and if the dogs killed a deer, it just was part of the game.

Now, when I read someone parroting the line that dogs never pack up to hunt prey, I am reminded of these stories about the old foxhound trials. Foxhounds may not be a particularly specialized breed in the way that Coppinger suggests.  He specifically says that scent hounds don’t have any real behavioral specialization at all.

But even the breeds that have specializations in their predatory behavior are capable of hunting in packs.

Take this story of a pack of retrievers killing a deer in Alaska:

A doe had to euthanized after it was attacked by four dogs at a Juneau wetlands.

Local resident Frank Rue called animal control officials Sunday morning to report the attack.

Rue said the dogs were two golden retrievers, a yellow Labrador retriever and a skinny black lab mix with a curly tail. The dogs appeared to be wearing collars.

“I found it very disturbing that people’s pets — and that’s the main thing, pets — would be running loose,” Rue said.

He spotted the dogs from his home about a quarter mile away and used his binoculars to see if there were any people with the animals, but saw none.

His wife then saw the doe. Rue believes the dogs chased the deer from Douglas Island.

“My reaction was, the deer looked like it was in trouble,” he said, “so I figured I would go out and see if I could catch a couple of the dogs, because I had some leashes, and find out who their owners were and get them away from the deer.”

It was low tide, so Rue walked across the wetlands and whistled to the dogs, who took off running.

Rue said the doe had a torn back leg and kept falling.

Authorities determined the deer had to be put down. The carcass was donated to the Juneau Raptor Center.

“When we examined the deer, all the injuries came from the dogs,” said Brian Weed with the Gastineau Humane Society animal control. “The deer didn’t seem to have any damage from anything else.”

At the scene, Weed and State Troopers Nick Massey and Shaun Kuzakin saw two golden retrievers running toward Douglas Island. They searched the area but couldn’t find the dogs.

Retrievers are supposed to have juvenilized predatory motor patterns, and thus, they would not be able to form a pack like these dogs did and inflict such injuries on a deer.

But they did.

Furthermore, these retrievers are all derived from ancestors on Newfoundland that had strong retrieving behavior but were also required to hunt for their own food at certain times of year. Free-roaming, “off-duty” water dogs in Newfoundland retarded the entire sheep industry on the island. The dogs were notorious sheep killers, even though they also were hard driving retrievers that would dive in to freezing water to fetch nets, lines, fish, seabirds, ducks, and even seals.

I happened to have owned a golden retriever that would retrieve anything with a soft mouth, including eggs. However, she learned from a Norwegian elkhound how to hunt, kill, and consume rabbits, and she would readily hunt rabbits for food. Her retrieving behavior did not keep her full hunting behavior stunted. It was like she had both behavior, and she knew when to use both– just as her ancestors in Newfoundland clearly did.

The other problem with the theory that dogs don’t hunt cooperatively is that they fall back on studies of street dogs from either urban areas or from developing countries.  Street dogs don’t get much of a chance to hunt because they live where there aren’t a lot of prey species. Further, they haven’t had any reason to learn how to hunt. Scavenging off the fat off human civilization is much easier. Dogs from developing countries also often have access to open garbage dumps, which are much easier feeding opportunities than what they’d get from hunting.

The only exception to these studies are the ones that look at stray and free roaming dogs in Italy, but then again, the dogs don’t have any reason to learn cooperative hunting. There are not many large game species in Italy, so even the wolves are forced to scavenge at garbage dumps. The dogs are more tolerant of each other than wolves are, so they are able to form huge packs around their garbage dumps and keep the wolves at bay. The dogs and wolves sometimes exchange genes, resulting in wolves with black coats and dew claws on the hind legs.

No one seems to get that there are dogs that evolved to live free of large garbage dumps.

We just don’t call them dogs.

They are better known as dingoes.

Dingoes are East Asian domestic dogs that went feral in the Australian bush.  They are not missing links between dogs and wolves. They are truly feral domestic dogs that are most closely related to street and village dogs in Indonesia. They form packs to hunt larger macropods, and they occasionally formed relationships with indigenous Australians in order to hunt cooperatively.

To debunk the crackpot dominance paradigm, some well-meaning people have attached themselves to a series of assertions that are just as problematic as what they are debunking.

People are trying to come up with hard and fast delineations between what separates a dog from a wolf. So far, I’ve come across only two that clearly separate them. Wolves have an active supracaudal gland. Dogs don’t. Dogs sweat through their feet. Wolves don’t. Well, at least northern wolves don’t. I would not be surprised to find out that southern wolves from the Middle East or the Indian subcontinent sweated through their feet. These are the subspecies most closely related to the domestic dog, and it would make sense that dogs and these wolves wold share this trait.

Clear delineations between dogs and wolves simply don’t exist.

The only really good way to understand dogs is to think of them as a subspecies of wolf that is specially adapted to living in a human environment.

The claim that dogs are just neotenous canids that never can hunt cooperatively in packs sounds very convincing on paper, but the real animals don’t read the books.

They are capable of learning many different behaviors from each other and from us.

If hunting together in a pack is something dogs obviously have learned to do, well, it sort of shoots the hole paradigm down.

And just as we reject the crackpot dominance theory, we have to reject the reactionary theory that came out in response to it.

Dogs are too complex for our attempts to simplify them.

That ought to be our rule whenever we try to consider them and their relationship with us.

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A survey of users of Kloof, an iPhone app that I’ve never heard of because I don’t own an iPhone, to see what owning a particular dog breed says about a person one intends to ask for a date.

The results say the following breeds are the top picks for a woman wanting to attract a man:

1. Golden retrievers

2. Labrador retrievers

3. Chihuahuas

4.  Poodles

5. Beagles

However, the survey found that men view women with chihuahuas and poodles as “high maintenance.”

The top five breeds for men wanting to attract women are

1. German shepherds

2. Golden retrievers

3. Labrador retrievers

4. Siberian huskies

5. French bulldogs

The list for breeds that attract women appears to be a bit more “wolfabooish” than the one that women would use to attract men.  Siberian huskies and GSD’s are look a bit like wolves.  Women seem to prefer men who keep less exaggerated breeds. Only the French bulldog on this list is removed from its more natural form.

Women don’t tend to care for men who keep bulldog, pit bulls, or Rottweilers.

[W]omen view men with these breeds as less than brilliant. In fact, people see men owning a Golden Retriever as 10 times more likely to be “marriage material” than one owning a Pit Bull. Pit Bull owners are also 10 times more likely to be considered “slimy” or “sketchy” than someone who owns a Siberian Husky.

These biases may not be particularly fair, but they are there.

And one should keep in mind that I’m obviously the statistical outlier here.

So take this survey with a grain of salt.

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On August 1, 2012, Yorkshire terriers are going to be allowed to participate in AKC earthdog events.

This is pretty good news, for Yorkshire terriers, although classified as toy dogs, do derive from small terriers that were used to control rats in coal mines and cotton mills.

There is a well-known terrier blogger who hates Yorkshire terriers and anything that’s not a JRTCA Jack Russell. However, he also regularly bitches about terriers becoming too large.

Well, here’s a solution:  Suck it up. Be a man. Get a Yorkie. You won’t become instantly homosexual when you own a toy dog. I know. Big news, eh?

But they’ll never be too large! And if you’ve spent any time around Yorkies, they are really nothing more than fuzzy little Jack Russells– and they are closely related to them.

If we wanted to breed a smaller Jack Russell, the Yorkshire terrier would be a good choice for an outcross, as would the toy fox terrier and the toy Manchester.

But no, it’s easier to complain that Jack Russells are getting too big than to consider possible alternatives that could be used to solve this problem.

***

Here’s a video from a person who was leading the campaign to get Yorkies recognized as terriers:

Source.

My grandpa used to hunt squirrels and grouse with a chihuahua.

She was as good as any feist or elkhound on squirrels, and with grouse, she was a bit better.

The grouse thought she was a fox, not a dog, and they just lit in the nearest tree when she flushed them.

Which made them easier to shoot.

Just because a dog doesn’t fit your prejudices doesn’t mean that it is useless.

That’s a lesson that too many “serious dog people” ought to learn.

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This past week there was a much talked about study that claimed that the reason why Lyme disease was on the increase is because Eastern coyotes are now killing all the red foxes.

Red foxes are a major predator of the main host for the Lyme disease- carrying tick, the white-footed and deer mice (Peromyscus).

Coyotes do kill red foxes whenever they encounter them, but to blame coyotes for the decrease in red fox numbers is a bit simplistic.

The study examined the number of red foxes, deer, and coyotes in the states of Wisconsin, Minnesota, Virginia, and Pennyslvania over a 30-year period. It found a correlation between the drop in red fox numbers and an increase in Lyme disease. Red fox numbers in all 4 states have dropped over this time period.

Of course, the first rule is that correlation does not imply causation.

There are lots of reasons why Lyme disease could be on the increase. I noticed that they didn’t try to examine the numbers of Peromyscus mice in the study– but it’s one that certainly key to understanding why Lyme disease might become more prevalent.

The study seems to be implying that the number of these mice is on the increase, yet it didn’t even look at them.

Of course, there are reasons why they might be in on the increase– and fox predation isn’t necessarily one of them. This entire region is experiencing longer breeding seasons for mice, which means they can have more litters during their lifetimes.  That wold mean that there could potentially be more Peromyscus running about in a given region now than in the past.

Further, milder winters are good for ticks.  More ticks can overwinter in egg, larval, and adult forms during mild winters than really  harsh ones. The winters in this entire region have been generally milder than they were in the past, which would tend to suggest that we should see an increase in Lyme disease.

I think that this factor is the more likely cause of the increase than a drop in red fox numbers.

However, even the assumption that coyotes are to blame for the drop in red fox numbers needs to be scrutinized.  Although Minnesota and Wisconsin have expansive farmland, Virginia and Pennsylvania have seen a decrease in farmland and increase in forest over this same time period. Dense forests are quite good for gray foxes (Urocyon), and although they are a bit smaller than red foxes on average, they are quite aggressive toward reds and drive them out of their territories. Grays prefer to have access to forests, for unlike the red fox, they readily take to the trees to escape predators.

Competition from gray foxes that are thriving as return of forested habitats seems to me a more likely reason for the red fox’s decline than coyote predation.

Red foxes have a distinct musky odor, and it takes quite a bit of training to get hounds to choose to hunt them over deer, and it seems very unlikely to me that coyotes would choose to hunt red foxes over other prey. They might kill them if they can catch them, but in general, they aren’t going to waste precious energy trying to kill red foxes when there are deer fawns lying around.

So although red fox numbers are on the decrease, it doesn’t make sense that the coyotes are entirely to blame for the decline.

I think the gray fox is a much more likely culprit, and its increase has happened only because forested habitat is expanding in much of East. If the land had remained largely agricultural, it is unlikely that gray foxes would be expanding their range, as they clearly are now.  The warming climate also has some effect here, for gray foxes are not as adapted to living in very cold climates as red foxes are.

But if gray fox numbers are on the increase, this really hurts the hypothesis that fox predation on Peromyscus mice is the main factor controlling Lyme disease. Gray foxes hunt mice just as readily as red ones do. The two animals are competitors for the same niche, and the gray has certain advantages over the red in forested habitats.  A gray fox is not limited to hunting prey on the ground. It can take to the trees to raid bird nests, and it is slightly more omnivorous than the red. If the two foxes have to compete in this environment, the gray can utilize more of the territory and thrive on a smaller acreage than a red fox.

Never mind that gray foxes will attack any red fox they encounter. They can also outcompete them for the same ecological niche.

So if the red foxes are in lower numbers than they were in the past, the mice are still being eaten by foxes. They are just being eaten by gray ones this time.

Further, coyotes are adept mousers. Before they came into the East and started hunting deer, they lived largely on rodents in the West. The idea that they are somehow less efficient predators of mice than red foxes are is pretty hard to justify. If anything, they likely eat more mice in a year than any red fox. Even if they do hunt deer and other larger animals, they still eat mice in order to augment their diet, especially if they aren’t pack-hunting coyotes.

And then there is the whole feral and free-roaming domestic cat factor.

Cats eat mice.

Everyone knows this, and cat numbers in the United States have never been higher.

Cats are likely killing scores more Peromyscus mice than ever before, and they could play a role in transmitting the deer ticks to humans.

Cats like to bring home their kills of white-footed and deer mice, and those little carcasses carry deer ticks, which then come off and attach themselves to the cats’ owners.

The authors of this study have not made a convincing case that coyotes are to blame for the rise in Lyme disease.

A much more likely culprit is the warming climate and the resultant mild winters.

Further, the authors haven’t shown that coyotes are the main reason why red fox numbers are down, when it is likely that a lot of more complex issues are at work here, including climate change, reafforestation, and the rise of the gray fox.

The idea that coyotes are to blame for this problem is quite reductionist.

Reductionist explanations, however, are exactly what lazy science journalism likes to use for headlines.

We should always be skeptical of such simplistic answers to what are more likely to be quite complex ecological issues.

Yes, coyotes do kill and compete with red foxes, but are they alone to blame for the decrease in red foxes and the rise of Lyme disease?

I really don’t think anyone can make that case.

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This is a Labrador retriever from France with what appears to have the somatic black spot mutation that appears in golden and Labrador retrievrs on occasion. It is not inherited, but the cells where the black spots are located do not have the e/e mutation that causes the yellow to red coat. Instead, this somatic muation makes the cells E/e, which gets expressed as black or liver. These dogs are sometimes called mosaics.

Alternatively, this dog may not be experiencing that somatic mutation. It might actually be a chimera, which happens when two zygotes combine. This dog could be made up of two distinct fertilized eggs– one that would become a black dog and one that would become yellow.

However, it’s much more likely that it is the result of the somatic muations. Chimeras of this type have not been found in domestic dogs.

***

This dog looks very much like an African wild dog, which is called Lycaon pictus (but should be called Canis pictus).  The title of this post comes from the African wild dog, for the coloration is so similar that one might be fooled into thinking that this is actually a Labrador retriever/African wild dog cross.

Though the pelage coloration is similar, it is caused by an entirely different genetic basis. African wild dogs inherit their “painted” coloration. If this Labrador were bred to another yellow Labrador, all of his offspring would be likely be yellow. The chances of him producing a puppy that will experience this mutation in the somatic cells are very low, and he would not be responsible for it if one did pop up. Somatic cells are not used in reproduction. Gametes are. This Labrador’s gametes are those of a normal black-skinned yellow Labrador.

See related post:

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De-hayed

The hay that was cut last week has since been baled and hauled off.

This is what remains:

It’s also rained since the hay has been removed, so it’s actually a bit greener than it might have been.

The crows and other scavengers have been eating well. The mowing and baling process cuts up any number of small animals, which are now just lying there in the open for the scavengers to eat.

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A little path through a bit of paradise.

My favorite color is green.

More specifically, this forest color of green.

And this time of year, in the long days of June, green dominates everything.

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