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In recent post I wrote about the new research regarding the thylacine’s size, I mentioned that maned wolves might violated the “costs of carnivory” rule, which states that predatory mammals that weigh more than 21 kilograms (46 pounds) must haunt larger prey sources to survive.

Maned wolves do exceed this size, but their diet does not consist of large prey. They are not a threat to ungulate livestock. They take only small prey, such as rabbits, rodents, and small birds. They could be a threat to chickens and other poultry, but they aren’t cattle killers.

On a superficial reading of their ecology and diet, one would assume they would break this 21 kilogram rule. The largest ones do get to around 23 kilograms, and if they are that large, then they surely break this “costs of carnivory” rule.

But they don’t.

The reason is they have a most unusual diet for a canid.  Between 40 and 90 percent of their diet can consist of a single fruit called a lobeira or “wolf apple.” The average diet of a maned wolf is around 50 percent vegetable matter, which means they aren’t as bound by the rules of carnivorous diets as other mammalian predators are.

The maned wolf first appeared in the fossil record in what is today the Desert Southwest what is called the Blancan faunal age (late Pilocene to early Pleistocene).

It entered South America, along with a whole host of other canids, and it evolved to a specialist niche as a grassland predator. Many species of similar-sized dog were also diversifying in South America, it is likely that it evolved its unusual diet as a way of avoiding competition with more carnivorous canids.

So vegetarian are maned wolves that when fed a typical wild carnivoran diet in zoos, they often develop bladder stones. Their kidneys cannot absorb a particular amino acid called cystine, and the excess cystine turns into stones.

Most mid-sized canids are true generalists in their diets. The exceptions are the maned and Ethiopian wolves. The Ethiopian wolf runs between 14-19 kilograms, so its rodent specialized diet does not violate the rule.

But the maned wolf’s heavily frugivorous almost takes them out of the predator guild entirely.  They are as almost omnivorous as most bears are, and all extant bear species exceed 21 kilograms at maturity.

So maned wolves don’t violate the costs of carnivory rule. They do so, because they are far less predatory than virtually any other dog species. They are certainly less predatory that other dogs of their size.

T

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One of the most common memes in our popular understanding of zoology is that the thylacine of Tasmania was the marsupial equivalent of the gray wolf.  This idea comes from a rather superficial understanding of its morphology, and lots of speculation about its behavior have stemmed from this popular understanding. One idea is that they were pack-hunters like wolves and dingoes, and they would have been murder on Tasmania’s sheep industry. Therefore, the final extinction of the thylacine was largely predicated upon a rational fear that the creatures would have been detrimental to sheep husbandry.

A lot of these speculations come from a belief that the thylacine was quite large. As I have discussed before on this space, larger carnivores are largely forced to hunt larger prey to survive. Otherwise, the larger size is of no benefit to the animal. Ecologists have found that the mass of 21 kg (about 46 pounds) is the size at which a carnivorous mammal can no longer subsist on smaller prey alone.

Thylacines were estimated to have weighed 29. 5 kg (about 65 pounds), which meant that their diet would have been larger prey. However, really big prey species are almost absent from Tasmania. The largest kangaroo in Tasmania is the Tasmanian Eastern gray kangaroo, which weighs is roughly the size of the smaller forms of white-tailed deer in the US.  Further, analysis of Thylacine skulls revealed that they could not withstand very much force. So the thylacine would not have been a very effective predator of prey the size of an Eastern gray kangroo, and it would have had a lot of trouble grappling with a fully grown sheep.

The fact that thylacines would have had problems killing large prey creates a contradiction in their supposed larger size.  If thylacines really did weigh 65 pounds on average, then they would be a major exception to the rule that larger predators must hunt larger prey to survive.

Well, a new analysis by researchers at Monash University has revealed that traditional estimates of thylacine size were greatly exaggerated.  Using complex morphometric analyses on various preserved specimens, the researchers revealed that the mean weight of a male thylacine was 19.7 kilograms (43 pounds). The mean weight of a female was 13. 7 kilograms (30 pounds).

These animals would have been roughly the same size of an Eastern coyote. Now, Eastern coyotes can live on large prey or small prey, and they can scavenge quite well. But they have skulls that can withstand blunt force from a sheep or a deer that a pack of them has run down. The Eastern coyote can live as a fox or a wolf, depending upon the conditions of the ecosystem in which it lives.

A thylacine would have been a smaller prey specialist, and because its weight did not exceed 21 kilograms, its subsistence on smaller prey did not violate the “costs of carnivory” rule.

Indeed, the only predatory mammal I can think of that does come close to violating this rule is the maned wolf, which sometimes weighs 22 or 23 kg. It lives almost entirely on small prey and fruit. This species has been persecuted for its attacks on livestock, but like the thylacine, it is not much of a threat to them.

Of course, there will be debate about this finding. Many historical accounts of thylacines suggest or imply or even outright claim that they were killing sheep and dogs left and right.

But the truth is that Europeans had their own concept of what a creature like this could do or was likely to do, and they merely transposed these ideas onto a creature that had the superficial appearance of a wolf or hyena.

We should by now stop trying to pigeonhole the thylacine into a marsupial wolf and should try to appreciate it for what it was.

Or might still be.*

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*I don’t believe they still exist, but I certainly wish they did!

 

 

 

 

way more black

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Sagan German shepherd

If you were to ask the average person how to classify a German shepherd in terms of dog breed taxonomy, most would say it’s guard dog, putting it somewhere with the Rottweiler and the boxer. Others might think it’s a primitive breed and might classify it with the Siberian husky and the malamute.

Those with a bit more dog knowledge would p lace it with the Belgian and Dutch shepherds.

Indeed, if you were going to ask me where I’d classify German shepherds ten years ago, I would have placed them as the German variant of what became distilled from a German-Belgian-Dutch prick-eared, black-masked herding dog landrace.

DNA studies have changed quite a bit of our understanding of dog breeds and their origins. In the initial attempts to classify dog breeds using only mitochondrial DNA found that German shepherds clustered with the mastiff breeds.

However, more recent genome-wide analyses have revealed something rather unusual. German shepherds are not directly related to the Belgian herding dogs at all. Instead,  one study found that they they are most closely related to the Berger Picard, the Chinook, and the Peruvian and Mexican hairless dogs.

Initial studies of regional Italian herding dogs using microsatellites suggested a close relationship between those dogs and border collies.  However, more recent genome-wide analyses have placed the Italian herders much closer to the German shepherd dog. Indeed, the German shepherd is very closely related to Italian prick-eared herding types, such as the Lupo Italiano and the Cane Paratore. These Italian herders and the Berger Picard all fit in a single clade with the German shepherd.

These findings upturn our assumption that the Belgian and Dutch shepherds are that closely related to German shepherds– at least in the bulk of their DNA.

However, the initial genome-wide study that found a relationship between the Berger Picard and the GSD also found that there was some GSD in the various Belgian herders, including the Bouvier des Flandres.

That means that at some point in the development of those breeds, German shepherds or proto-German shepherds were crossed into them. Crossing German shepherds with the Malinois isn’t an uncommon practice in some working dog circles even now. Apparently, this practice was done more frequently when the breeds were not so defined as they are now.

And it should be noted that only tiny ancestry blocks from German shepherds into the Belgian breeds. The bulk of their DNA derives from very distinct dog stocks. The Belgian herding breeds are more closely related to British herders and Western sighthounds than they are to German shepherds.

These genome-wide studies have lots of interesting findings, including that xoloitzcuintli and Peruvian hairless dogs are almost entirely derived from European herding dogs and that their sister breed is the Catahoula. Because of this relationship to these Latin American dogs, the Catahoula is probably more derived from Iberian herding breeds than from French ones. It is likely that the hairless dogs of the New World are the originators of their hairless trait, but because it is conferred via a semi-dominant allele it was easily transferred onto a population that consists of dog of European origin.

The relationship between German shepherds and Italian herders is easily understood. German shepherds are heavily derived from Bavarian and Swabian sheepdogs, and Bavarian shepherds were often grazing their sheep in the Alps during the summer, as were the Italian shepherds. The dogs exchanged genes in those high country meadows, and their pups went onto found populations on both sides of the mountains.

This story fits the genomic data, but it make the Berger Picard a bit of an anomaly. Picardy is in the northeastern France, a long distance from the Alps. It would make more sense for this breed to be more closely related to the Belgian shepherds and the Bouvier, but it is not. The North European Plain is easier for dogs and their genes to flow across, but the Berger Picard is very close the German shepherd breeds and its Italian cousins.

I do not have a good answer for why this anomaly exists. I don’t know much about the Berger Picard or its history. Maybe it became a very rare breed and was interbred heavily with German shepherds, or maybe the region is very connected through markets to the Alps or Bavaria or Northern Italy.

Maybe someone can answer these questions for me.  It seems weird that the Berger Picard is so closely related to dogs that have origins in Southern and Central Europe rather than adjacent Belgium.

The evolution of herding breeds is complex. Apparently, having a dog with a wolf-like phenotype is useful for herding flocks. The Belgian shepherds apparently evolved their type independently of the German shepherd, the Berger Picard, and the Italian prick-eared herders. Perhaps sheep just respect that look more, and it has some advantage in their management.

As we have seen, dogs can evolve very similar physical traits in parallel with each other, which is why we must always be careful when creating an umbrella classification for different breeds.

Just because they look alike and have similar functions does not mean they are that closely related.

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Dead Blue Crayfish

One of the mysteries of the day is why there was a dead blue crayfish on top of my garbage bin this morning. I don’t know the species or how it got there.  Still vexed.

crayfish

crayfish 1

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The German shepherd staple is the ball on the rope.

Reichshund

Reichshund

When Germany unified in 1871 under the Prussians,  the new nation began a period of modernization and industrialization. For lack of a better word, it aped much of what the British did. Britain was the world super power at the time, and it made sense to do many of the things that made it successful.

Agricultural improvement was a subject for which the British had a great understanding, and Germans were deeply involved in their own selective breeding projects in a wide variety of species.  Dogs were no exception. Indeed, the Germans largely adopted the British dog fancy system as a way of improving canine stock.

In Edward Tenner’s remarkable piece called “Constructing the German Shepherd Dog,” the author points out that German dog fancy was largely derived from the British one, and by the 1880s, there were three main factions that were operating in the field of dog breed improvement:  a faction that was working breeding good urban pets, a faction that was interested in experiment with various working breeds to improve them for greater utility, and a faction that was concerned with dogs of the rural gentry, especially Great Danes.

It is in the latter that it most resembled that of the British dog fancy. The dog fancy had come from learned nobility or those very near to reaching peerage, and the main interests were dogs used for hunting or dogs that were used for guarding large estates.  The first dog shows in England were about setters and pointers. They later came to encompass virtually every hunting dog, as well as the noble mastiffs.

This part of the German dog fancy was particularly concerned with Great Danes. Bismarck, the Prussian statesman whose Realpolitik had made unification possible, was a much-esteemed leader of the new nation. He was very much a fan of the large boarhounds, and the dogs that surrounded his court and those of his associates came to be known as Reichshund or “dogs of the Empire.”

In this way, the Germans aped the British. The British heavily promoted the improvement of very large mastiffs in the early days of their fancy, and the German did much the same with their own indigenous mastiff.

One of the great ironies is that English speakers call this breed a “Great Dane.” Buffon called the dog “Le Grand Danois,” and such a misattribution has continued in the English-speaking world almost without challenge.  Some English-language authors called the breed the “German boarhound” or just “boarhound,” which are far better names.

But if one knew of the popularity of Great Danes among the elite in Germany in the early decades of the Empire,  it would be hard to see them as anything other than German.

Indeed, the foundation of breed as we know it today started in Berlin in 1878, just a few years after unification. Various boarhound fanciers–almost all of them nobles who either used them as catch dogs or as estate guardians– got together and began combining their strains.

The breed had a terrible reputation in England. Rawdon Lee saw the breed as a menace and recounts a story in which a Great Dane nearly killed a Newfoundland dog.  He also lamented that dogs exhibited at the Crystal Palace shows spent most of their time growling and snarling at other dogs and exhibitors.

This breed did have a reputation very much like we see about pit bulls today, and they are three times the size of a pit bull.

When the Germans began the pioneering of the modern concept of a police dog, the Great Dane was the breed that was used.  In the late 1890s, Franz Laufer became a the police commission in Schwelm in Westphalia, where he became instrumental in developing a modern police force.

One thing that Laufer thought was necessary was to have dogs that worked for the police. Initially, he thought the dogs’ main utility would be in protecting the police from hostile subjects, and the breed he chose to work as a police dog was the Great Dane. Indeed, the first modern police dog was a Great Dane named Caesar, who was enlisted for service in 1897.

Great Danes were the first police dogs, but of course the breed isn’t that well-suited the task. They lack the biddablity of the shepherd dogs, and in the late nineteenth and early twentieth centuries, this breed had much of a fighting spark than could ever be made safe for the public. They are also very large and aren’t as easy to transport. They also take years and years before they mature mentally.

The Great Dane, the boarhound, the Deustche Dogge, or German mastiff was really the first attempt by the German Empire to create a unified national breed. But they were mostly the dogs of the elite, because of the limitation in turning them into truly versatile working dogs, they were eventually replaced by the German shepherd, a dog from more rustic and working class roots.

The reputation of this breed has changed quite a bit. Americans grew up on The Ugly Dachshund, Scooby Doo, and Marmaduke formulation of the breed. One cannot do a search for the Great Dane and not see the words “gentle giant” mentioned in the majority of your results.

The breed has been toned down greatly from that über that frightened people all over the English-speaking world. Indeed, the breed is almost never used to catch wild boar and feral swine, which was its original purpose.

The breed still has some capacity for aggression, especially toward other dogs, and some can be absolutely dangerous creatures.

But the passing 123 years since time of Caesar in Schwelm, the breed has become a companion animal and a novelty. Virtually no one breeds a real working Great Dane. Americans prefer their own strains of catch dogs, as do the Australians and New Zealanders, and such methods of hunting are illegal in Germany and most of Europe.

It failed as a national dog. It made a short career as a police dog.  It no longer makes the swine squeal.

It fits in now because of its novelty and its rebranding. But in its blood still courses the boarhound of yore. Its blood courses in the Dogo Argentino and maybe a few other feller mastiff strains as well.

But the dog itself go on into the twenty-first century, in hopes to find a space in a world no longer needing such a creatures as true German boarhounds of the old strain.

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Dead Polyphemus

One of the weird things about living in this part of North America is that we have big moths. This is a dead Polyphemus moth. It is named for the cyclopes in Odyssey. Those big eye spots sort of remind one of a cyclopes, but they also scare off predatory birds that don’t want to attack something that is looking at them.

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