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Archive for February, 2012

The narration is very hard to hear, but it is amazing footage:

Source.

These dholes truly are Cuon alpinus, the mountain dogs.

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This painting is marketed as “Landseer Newfoundland” by Edmund Bristow.

I cannot find the date for the painting, but it is unlikely that this was the original title.

The simple reason is that Bristow was a contemporary of Landseer, and the black and white large Newfoundlands didn’t get that name until some time later.

Newfoundland dogs of various types were known for their retrieving prowess.  The big Newfoundland, sometimes call the “Large Labrador,” was capable of retrieving quite well. Its exact origins are not clear. It is even unclear if the dog existed in this form in Newfoundland itself or if this dog is nothing more than a European improvement upon the native water dog of Newfoundland.

I think the bulk of the evidence suggests the latter, but I could be wrong.

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Santorum

This pretty much sums it up:

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"Der November" by Joachim von Sandrart (1643).

Matt Walker of the BBC writes about a very interesting paper in the journal Evolution that discusses why animals have not been able to evolve against human predators.  Predators and prey are normally locked in an evolutionary arms race in which predation places selection pressures upon prey to evolve defenses. The two most common ways that prey species evolve defenses against predation are to grow really big or produce toxins, but neither of these are particularly good defenses against human predators:

“The spread of modern humans represents one of the great ecological and evolutionary transformations in the history of life,” Prof [Geerat] Vermeij writes in Evolution.

We hunted and gathered on land, but soon began exploiting intertidal zones, taking shellfish and fish. Such intertidal zones were important food sources for prehistoric human populations living in places as far and wide as South America, South Africa, California and Oceania.

Then we started taking big animals. When we did the very adaptations that offered protection against natural predators attracted rather than deterred human hunters. The huge size of mammals such as bison or whales made them juicy targets for meat-hungry humans for example.

Other defensive ornaments became disadvantageous as humans evolved into super-predators. Elephants were killed for ivory, crabs and lobsters fished for their large meaty claws. These once advantageous traits became liabilities in the modern, human-dominated world.

We didn’t just take large species, we also preferentially harvested out the largest individuals of smaller species, a problem that persists today.

Prof Vermeij has examined the degree to which this happens.

He looked at one group of animals, marine molluscs and echinoderms such as starfish, and surveyed all the scientific research into how they have been exploited by humans. We select the largest individuals among 35 of 40 species studied, he discovered.

That means that size is no longer a refuge. Whereas growing big may have been one defence against natural predators, it offers no defence against human super-predators.

Sticking to rocks, as limpets do, is no good either as humans have invented picks and knives to prise them off.

Prey animals may do better to become toxic instead, and there is evidence that some marine species have become poisonous to people, either producing their own toxins, or by harnessing toxins produced by microbes. Reef fish and crabs are often toxic to people because they contain unpalatable, and sometimes lethal, dinoflagellates, for example.

But humans have found ways to get around this too. Many toxins need to be concentrated into organs such as the liver. And humans have learnt to remove these, to avoid their ill effects.

In short the way humans hunt appears to be the main factor preventing animals evolving adaptations to defend themselves from us.

Animals do respond to selective pressures, even over short time scales, and many species have responded to humans being super-predators, says Prof Vermeij.

By eliminating large apex predators, secondary predators have boomed. As cod numbers crashed in the 20th Century, their place was taken by an abundance of shrimp, lobster and crabs, which in turn feed on marine snails. As a result, these snails may have evolved thicker shells to protect themselves against these marauding shell-crunching crustaceans.

But we hunt on too grand a scale, with too much ingenuity, targeting the biggest animals.

“Our arrival and technological history has engendered an enormous change in the evolution of most species on Earth,” says Prof Vermeij.

In evolutionary terms, we leave our prey with nowhere to go. They have no way to defend themselves and simply cannot respond.

And that, says Prof Vermeij, represents a cataclysmic shift for species on this planet, the implications of which, he adds, we have barely begun to understand.

I  have long wondered why predation by humans is not considered more carefully in our discussions about evolution.

I have often thought that the reason why people have such a hard time taming wolves now and may not have had such problems in the past is that wolves experienced an unbelievable selection pressure in the form of human persecution.  When wolves became too wary to kill with weapons, we resorted to poisons and traps, and all of these pressures left behind only the most “paranoid” and reactive individuals to pass on their genes.   This might go a long way to explaining why it was so easy for ancient man to tame wolves, but it is now quite difficult for us to do so. And even if we wind up having a wolf that is imprinted upon humans, the chances of it being more like a friendly and docile dog are very low. However, there are and were wolves like this in modern times– Wags and Romeo are good examples.

I’ve also wondered about the behavior of white-tailed deer when they see me approach. I am from the only species that can kill a deer as soon as I get a good clear view of it. No other animal that can kill a deer can do that. All the rest– be they bobcats or coyotes– most put their teeth on the flesh. So when a deer sees me approach, it must know that the threat is that much more than if it sees a pack of coyotes approaching at the same distance.

I’ve also wondered about the way squirrels run away from people. They always try to stay on the opposite side of the trunk from where a person is standing.  Any other animal that would pursue a squirrel into the trees– like a fisher or marten (which used to be found here)–would follow the squirrel course almost exactly. It would have no reason to try keep itself on the other side of the trunk. Such behavior would have some advantage against raptors, but raptors would come down on the squirrel.  The threat from a human hunter would come from the other direction. Somewhere along the line, they evolved this strategy to avoid being shot.

The behavior of ruffed grouse has also changed dramatically as the result of human hunting.William Harnden Foster wrote the first important treatise on sport hunting ruffed grouse in New England, simply entitled New England Grouse Shooting.  Writing in the early twentieth century, Foster discusses the evolution of ruffed grouse behavior in response to rapacious market hunting. Market hunting was always a major threat to American wildlife, and although today we like to castigate Africans for their “bushmeat” trade, it was actually perfected in America. As Americans gained more wealth as a result of our industrial revolution, they came to want wild game meat.  Fine restaurants and markets in major cities offered the flesh of all sorts of wild animals, and many species, including white-tailed deer and Eastern wild turkeys nearly became extinct through this early American bushmeat trade. Grouse were always in demand for the table, and in the early days, they were easily killed. Ruffed grouse apparently originally lived in small flocks, and when a dog flushed them, the whole flock took refuge in a tree, where a hunter could easily pick them off with his fowling piece.  Over time, this selection pressure left behind only grouse that took off and flew greater distances from where they were flushed. And it also made the grouse much more solitary. Today, it is very rare to find more than one grouse in the same spot, unless it is a hen and her poults.

In no case has these animals evolved a very effective defense against human predators.  So long as we have guns, we can get them.

We’ve even been able to kill the largest whales very effectively. In the later days of whaling in Newfoundland and the Maritimes, the blue whale and the finback were rather easily subdued with harpoons that had extra blades that pojected out as soon as they main shaft lodged itself in the whale’s flesh.  These extra blades caused the whale to bleed out  and die more rapidly. All the whalers needed was a strong cord connected to the harpoon and a very stout boat to wait it out.

It is only now that we’re beginning to realize what human predation is actually doing to the evolution of animals and to the ecosystems in which they inhabit.

It is really humbling to realize that we could have this effect.

And it is also unusually disquieting– even a bit terrifying.

 

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Jack Russell up for adoption

Named Dick:

Willie’s dad sent me this one!

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A dingo ate my shark

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There is a famous book on the red fox entitled Red Fox: The Catlike Canine by J. David Henry (1986).

Never mind that foxes are not canines.  “Canine” refers to the dogs in the tribe Canini, which includes all the dogs in the genus Canis and its allies, Cuon and Lycaon, and all the South American wild dogs. True foxes belong to the other tribe within extant canids– the tribe Vulpini.  Red foxes, like all members of the dog family, are canids, but they are not canines. They are vulpines.

One of the main theses of the book is that red foxes are like cats. They have pupils that can contract to a vertical slit, a trait they share with cats– and all other vulpine foxes!  This adaptation allow them to adjust the amount of light exposure to their lenses, allowing them to see at varying levels of light. It is definitely a good adaptation for hunting at night.

Red foxes also eat a lot of mice.

So that makes them the true cat-like dog?

Well, there is another wild dog that lives in many of the same areas as the red fox that is far better candidate for this title than any vulpine.

I am, of course, referring to the so-called gray fox (Urocyon cinereoargenteus). Although it has classically been referred to as a vulpine, the most in-depth genomic study on the dog family showed it to be nothing of the sort. It is actually a very primitive wild dog species whose line branched off from the rest of the canids 10 million years ago. This is the oldest extant lineage within the entire dog family, and it should be regarded as neither canine or vulpine. It is a basal canid that should be regarded as existing as part of its own tribe.  The only good reason to call it a fox is because it superficially looks like one.

As a primitive canid, it retains some features that it shares with only the raccoon dog (Nyctereutes procyonoides). The raccoon dog is a native of Northeast Asia, and it has also traditionally been considered a basal canid. However, the same genomic study that found the  gray fox to be a very ancient lineage also found that the racoon dog is actually a basal vulpine, as is the bat-eared fox, which has also been traditionally regarded as a basal canid. If we are to accept this new taxonomic position, then the raccoon dog, on average, would be the largest vulpine, not the red fox.

The most important traits that the gray fox shares with the raccoon dog are its specialized adaptations for climbing. Both of these species still retain the hooked claws that make trees more readily accessible, and both are relatively short-legged, which allows the body to hug branches and trunks more closely as it climbs. However, the gray fox is by far the more arboreal of the two, and it can access trees with all the agility of a domestic cat.

And because it can climb trees, it is actually much more ecologically like a domestic cat than the red fox or any other vulpine is.  If one can readily climb trees, then one can readily raid bird nests. Most of the United States never had small cats. The smallest species of cat that was widespread in the US was the bobcat, and in many areas, bobcats tend to attack larger prey than any domestic cat would.

No one really has examined how many birds gray foxes eat every year, but it is surely not to be a small number.

Of course gray foxes actually have their paws in several different niches.  They hunt rabbits and rodents in much the same way that red foxes do, and in part of the Eastern US, they are thought be a more significant predator of the various species of cottontail than red foxes are.   And gray foxes are quite omnivorous, often eating fruit and vegetable matter in much the same way we’d expect from a raccoon.

Gray foxes are really cat-like in their  movements.

The first one I ever got a good look at was running straight towards me as it pursued a cottontail rabbit that the passage of my feet next to a tangle of multiflora rose happened to flush out. The rabbit bolted uphill toward the place where the fox was waiting, and then upon seeing the fox, charged for the undergrowth to my left.  The fox took off after the rabbit and came running toward me. Because of its color and because it was running so fluidly, I thought I was actually looking at a cougar.

It made me stop.  Let’s just say that!

Miley was just a small puppy at the time and was running along beside me And she stopped, too. Old Strawberry, the 14-year-old golden, was plodding along behind me, and she stopped right when I did.

The fox suddenly slammed on the brakes, and it looked me over. It didn’t expect to see me coming along, but as soon as it realized what I was, it made two or three hard galloping leaps for the cover.

And it was gone.

But I can never forget those two or three seconds that it stopped short and stared up at me.

Anyone who has been around dogs for very long can read a gray fox, even if 10 million years of evolution separate them from domestic dogs.

I could see the expression on its face switch from the intensity of a predatory dog locked onto its prey to  that of absolute terror when it finally realized that its desire for a rabbit dinner suddenly nearly delivered before its worst enemy– a human with a pair of dogs in tow.

Gray foxes fascinate me to no end.

Theirs is an ancient lineage. This land was theirs before the first red foxes wandered down out toward the end of the last glacial maximum– and even after that, the red fox would largely be a stranger to these woods until at least the eighteenth century, when British colonists imported large number of English foxes to augment their numbers for fox hunting purposes. These particular woods probably never had a healthy population of red foxes until  the 1830’s.

We like to think of foxes red and gray, but I think this is not the best way to consider them.

There are red foxes.

And then there is Urocyon.

The little cougar dog of the undergrowth– and sometimes of the canopy!

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Bigfoot on gamecam

LOL. This is very well done!

Source.

 

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Miley update

Miley is about 90 percent better.

Her jaw and larynx are no longer paralyzed.  She can bark and drink and eat normally.

She will not have to see a specialist. Her paralysis was likely the result of a rare viral infection.

However, a per vet’s orders, she can no longer wear a collar.

Collars might eff up her recovery or exacerbate whatever defects still exist in the nerves.

So she’s now wearing a harness.

 

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The answer to this “Identify” query is that these dogs are Harzer Fuchs.

Fuchs means fox in German, and these dogs do look quite a bit like foxes.

They are border collie-sized herding dogs that remind some of German shepherd dogs and to others B, elgian and Dutch shepherds. In my eyes, they are a bit like gold-colored mudis, a somewhat smaller Hungarian herding dog.

The Harzer part of the name comes from the general geographic location of these dogs.   These fox-like sheepdogs are very common in the Harz mountains of northern Germany.

These dogs are actually a type within a greater landrace called the Altdeutsche Hütehunde (Old German herding dog or Old German shepherd). Various dogs of this type have existed in the German speaking world for hundreds of years. The modern German shepherd is derived from regional forms of the landrace, exspecially those from from Thuringia and Württemberg.

Dogs like the Harzer Fuchs and its relatives within the landrace would have been the dogs with which my ancestors would have had the closest relationship.   When I was a child, I thought they actually used modern German shepherds to herd sheep and mink-like dachshunds to hunt badgers.

But the truth is that as German working class people who lived long before there were “improved types” that became breeds, they used dogs that were much more varied in appearance and type.  They didn’t have time to breed for giant German shepherds, as the Shiloh shepherds are, or to breed dogs with sloping backs, which we see in modern show shepherds. They just bred dogs that could do the task. If some were red and fox-like and others were shaggy or even blue merle, they really didn’t care that much.

I would love to see some genetic studies on dogs in this landrace to see exactly how they fit with modern breeds. They appear to transcend out concept of breed entirely, and they are so varied that it is obvious that they have very little ancestry from modern breed dogs. Because they may have never existed as true breed dogs,  they might prove to be as genetically diverse as some Asian and African dogs, which means they could tell us a lot about the evolution of dogs in Europe.

I don’t know why these dog haven’t been studied more.

It may be that most people just don’t know about them.

One can see in these dogs what might be the rough form of a variety of breeds. The shaggy ones could be proto-schnauzers or poodles– some of which are called Schafpudel (“Sheep poodle”). The merle ones, called “tiger dogs,” might have played a role in founding the Australian shepherd, which was developed in the American West from diverse herding dog stock.  One can see collie in some of these dogs, along with German, Dutch, and Belgian shepherds.

So it’s possible that these dogs represent the ancestral stock that formed all of these improved breeds, but they have existed for centuries outside of the closed registry system.

The notion that these dogs might be at the root stock of many European breeds is not new.

Buffon believed that the chien de berger,  the French herding dog landrace, was the ancestral dog from which all dog breeds descended.

He was stretching it a bit, but Germany is at the crossroads of Europe. Lots of different people have moved across its plains over the millenia, bringing with them diverse dog strains.

Within the DNA of these dogs is a story that is waiting to be revealed, but as far I know,  no one has closely examine them.

I think it’s time.

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