If you frequent this site, you’ll know that I’m much more partial to cats than to dogs, but dogs do excel in one respect: they better demonstrate the power of artificial selection.
Every year I present to my students a much-tattered poster, made by the now-defunct Gaines dog food company, showing the various dog breeds recognized by the American Kennel Club. I use it to show the students how the lineage of the gray wolf (the ancestor of all domesticated dogs) contains ample genetic variation for almost any trait you choose: size, body shape, coat color and texture, and even behavior.
This, in turn, demonstrates that selection—artificial selection rather than natural selection in this case, but the principle is the same—has plenty of raw material to work with. As Darwin famously said in The Origin, “Breeders habitually speak of an animal’s organisation as something quite plastic, which they can model almost as they please.” And if that kind of genetic variation is present in one rather inbred lineage, then it is certainly present in nature. Remember that neither natural selection nor genetic drift could operate, nor selection produce complex adaptations, if genetic variation wasn’t ubiquitous. Demonstrating the pervasiveness of inherited variation was, then, an important task in verifying Darwin’s theory, and one reason he devoted so much space to artificial selection in The Origin.
The problems that afflict dog breeds, however, also demonstrate two other principles of genetics: inbreeding and pleiotropy. Inbreeding, because many breeds stem from only a few founders, and so bad recessive alleles can accumulate, causing genetic disease and malformations. (Breeders do attempt to eliminate this by outcrossing, but of course that dilutes the desired traits of the breed).
“Pleiotropy” is simply the observation that an allele (form of a gene) can affect several traits independently. Many eye-color mutations in flies, for example, reduce fertility independent of the mutant color. As an example in dogs, the short snouts of breeds like bulldogs can lead to respiratory problems.
Given that, here, from the website Pedigree Dogs Exposed, is a splenetic take on the evolution of the American cocker spaniel, one that sounds as if it were written by Andy Rooney. The change in this breed over 100 years shows not only the power of the breeder to change a lineage in only a few generations, but at least one pleiotropic effect of a change in the coat:
This breed needs to be re-classified as a Toy breed. Its retention in the Gundog Group does a disservice to those breeds that can and do still do the work for which they were bred. And, frankly, this amount of coat is a welfare issue – not perhaps directly (as long as it is groomed regularly), but because top show dogs can’t possibly get much of an opportunity to be dogs. There’s certainly no way they could do a day in the field – it would ruin that all-important coat.
And how on earth do the males pee without soaking their coat?
Here’s what the Americans have done to the Cocker… from sturdy sporting dog to dome-headed,over-coated, increasingly-brachycephalic hairdresser’s dog in 120 years. [JAC: I’ve chosen but a few pictures from their series.]
I make no claims for the veracity of this analysis, so if you own an American Cocker Spaniel, don’t complain to me!
The American Cocker spaniel, originally a sporting dog bred to find and bring back game to hunters, diverged from the English cocker spaniel in the late 19th century. One could, then, consider this divergence an example of incipient speciation, except that the breeds will almost certainly not become full species as they remain reproductively compatible. (My students often ask me whether dog breeds are separate species, and I say “no” because of this reproductive compatibility.)
As for the results of inbreeding and pleiotropy, one dog-breeds website reports this:
Some major concern in American Cocker Spaniels are cataracts, glaucoma and patellar luxation. Some minor concerns are hip dysplasia, ectropion, entropion, PRA, allergies, seborrhea, lip fold pyoderma, otitis externa, liver disease, urolithiasis, prolapse of nictitans gland, CHF, phosphofructokinase deficiency, and cardiomyopathy. Occasionally seen are gastric torsion and elbow dysplasia. Also IMHA (Immune Mediated Hemolytic Anemia) One owner stated, “Our cocker never had a sick day in her life until she suddenly became lethargic and urinated blood. Six days later, and $3000 in vet bills, she died. I know you can’t list every illness due to space limitations, but the internal medicine specialist that treated our dog said that IMHA is relatively common in cockers, and almost always fatal. It’s a fast-acting, silent killer.
This information all was inspired by a piece at the Manchester Evening News reporting a £ 500,000 grant given to researchers at Manchester University. These include our own Matthew Cobb, and the Evening News describes the study as follows:
The unique study will see zoologists and historians going back in time to see how far dogs have been transformed over the last century. Michael Worboys, an expert in the history of science, said breeding, training and socialising meant many of today’s breeds were barely recognisable from their 19th-century ancestors.
He said: “The dog was transformed in the 20th century by the application of science and medicine. No animal species has been more altered in size, shape, colour or temperament by human selection.
“No species has a closer relationship with humans. And no species has their health treated in a manner so close to what humans enjoy.
“We will study how changing ideas and practices with breeding, feeding, training and treating have essentially remade the modern dog – whether as pet, show dog or working animal.”
Here’s a picture of Professors Worboys (l.) and Cobb (r.) with Melsha the dog. I hasten to assure readers that Matthew is more partial to cats, and has two of them. I regard this grant, in fact, as a provisional act of treason.
PIT OF DESPAIR, Birmingham, Tuesday (UNN) — A South Somerset Atrocity Terrier named Soberhill Black Medik Markenbrow Beatrice Vraibleu has beaten 25,000 canine rivals to win Best of Show at this year’s Crufts in Birmingham.
The event, held in the Gladiator Pit at Birmingham’s National Exhibition Centre, attracted more than 143,000 freak-show ghouls and failed concentration camp doctors.
Soberhill Black Medik Markenbrow Beatrice Vraibleu is owned by top breeder Diana Mosley-Mengele, 48, of Gloucestershire. “It is unbelievable. This dog has done so well. It is the greatest accolade you could wish for. We may have to think about retiring him now because there is nothing left for him to do. Of course, we can’t breed from him, because the genitalia have been entirely bred out of the line in order to allow the extra legs to grow in.”
Second place went to a one-year-old pit bull terrier called Thatcher, who, in a virtuoso display of the breed’s skills, ate one of the judges.
Dog breeding in the UK is concerned with every detail of a dog’s appearance. “The perpetual haemophiliac bleeding from the snout must trickle along approved lines,” said Miss Mosley-Mengele. “In addition, the lifelong whimperings of pain must be pitched between 3000 and 5000 Hertz. I had to drown four bags of culls on this point in the last month alone.”
Other events in the Arena yesterday included the Flyball Team semi finals and finals, the Agility International Invitational and a parade of Obedience winners. Particularly good showing in the Obedience trials came from those dogs who helped in corraling their fellow canines and assisted their owners in the vital genetic and surgical work needed to further the show-dog hobby.
Victoria Stilwell, star of the TV show Cull The Unterhünd, set a few hearts aflutter around the show whilst filming a special episode of the popular programme and personally chopping up bloody hunks of cull to throw to the aspiring Crufts entrants.
Crufts was established in Argentina in 1946 by public-spirited recent German immigrants who felt their skills and hobbies were no longer welcome in their homeland. This year’s event has been overshadowed by accusations that the show is cruel, with animal charities and the International Criminal Court in the Hague expressing their concerns. Show organiser the Kennel Club is putting measures in place to deal with the problem, starting with kidnapping PETA activists and mincing them for dog food.
(original by me at http://uncyclopedia.wikia.com/wiki/UnNews:Crippled_diseased_genetic_fetishisation_wins_Crufts )
Cats. Interesting creatures. But they are only little more a pet than a lizard or a rat or a small weasel of some sort. One is only a surrogate mother to a cat, whereas one is both a surrogate mother and a pack member to a dog. Some dogs would die attempting to protect a human child from a bear (mine would). No house cat would do the same.
And dogs do not insist on constantly presenting their anuses for — what, inspection? Cleaning?
Hey, everyone knows that cats are all Zen-like and totally have inscrutable motives for everything, due to them being the ultimate mystery and way too deep for understanding, and not just because their smitten owners are engaging in anthropomorphism and projection on an epic scale, so don’t you dare suggest such a thing!
They use butt smell the way we use faces. Presenting the anus is the canine equivalent of making eye contact.
Oops, misunderstood your post. Dogs also show off their butts for the reason I mention above.
Dogs do not back their arses up right into your face with tail held high.
I’m curious, Christopher, have you ever owned a cat? While I’ll admit, dogs are very attached to their humans, I’ve certainly known cats I’ve been close with to come running if I stubbed my toe, or sounded hurt. Admittedly, they weren’t able to do much, but I’ve never got the impression that they didn’t care about me.
Now, other people’s cats are a different story, they only vaguely care. But even then, they are far, far more friendly and interesting than a lizard or a rat (and even rats and weasels can be socialized to be more fun).
@sajanas:
Yes, I’ve a rather gregarious, chummy male cat whom I’m quite fond of, as far as cats go.
Still, there’s no contest between that animal and my German Shepherd x St. Bernard mutt — the cat does not guard my disabled friend whenever he comes over, keep raccoons out of the trash, allow toddlers to climb on him (and guard said toddlers in public from other dogs), etc. My dog Stella does.
Granted, the cat was easily trained to shit in a designated location…but then so was my leopard gecko. 😉
Treason? At least it isn’t funded by Templeton!
You should add a Cocker Spaniel Spirituality measure. That should be good for $500k.
It’s shameful how we treat animals really.
I’d like to see a good article on the evolution of cats and dogs from their common ancestor.
http://en.wikipedia.org/wiki/Miacoids
dogs-cats common ancestor
Carnivorans evolved from miacoids about 55 million years ago during the late Paleocene.[4] Then, about 50 million years ago, the carnivorans split into two main divisions: caniforms (dog-like) and feliforms (cat-like). By 40 million years ago the first clearly identifiable member of the dog family Canidae had arisen. It was called Prohesperocyon wilsoni and was found in what is now southwestern Texas. This fossil species bears a combination of features that definitively mark it as a canid: teeth that include the loss of the upper third molar (a general trend toward a more shearing bite), and the characteristically enlarged bony bulla (the rounded covering over the middle ear). Based on what we know about its descendants, Prohesperocyon likely had slightly more elongated limbs than its predecessors, along with toes that were parallel and closely touching, rather than splayed, as in bears.[5]
The Canidae family soon subdivided into three subfamilies, each of which diverged during the Eocene: Hesperocyoninae (~39.74-15 Mya), Borophaginae (~34-2 Mya), and the Caninae (~34-0 Mya) lineage that led to present-day canids (wolves, foxes, coyotes, jackals, and domestic dogs). Each of these groups showed an increase in body mass with time, and sometimes exhibited a specialised hypercarnivorous diet that made them prone to extinction.[6]:Fig. 1 Only the Caninae lineage, commonly referred to as “canines”, survived to the present day.
“I regard this grant, in fact, as a provisional act of treason.”
Well, perhaps Fortune will smile and a grant will manifest itself to fund research into how the feline attained its current great state of altruism and self-abnegation.
And how theologians became so wise!
Thanks for blowing the woof off this travesty.
Uh, oh, soapbox time.
I have bred animals all of my adult life. I had sheep for several years, and bred and trained Border Collies to work with the sheep.
I have had dairy goats since 1980.
If we are going to use animals, we have an obligation to treat them in such a way that they don’t suffer to feed our egos. Breed standards should support health, longevity, and in the case of working animals, productivity. They should NOT, just because of “style”, be forced to develop detrimental traits.
Goats are used for meat, milk, and fiber. All of these ends have been developed over the years without sacrificing soundness. A glaring exception is in African Pygmies, which in this country are raised purely for pets. Their breed standard calls for small, cobby (short) bodies with steep rumps. This causes reproductive problems, as the kids tend to not be able to get out very easily, both because of the size of the dam, and because of the crookedness of the birth canal. All of the other breeds, meat, milk and fiber, call for good body length and level rumps.
People who breed working animals can’t afford to have a bunch of problems that lead to the loss of their stock. People who breed pets don’t usually care, although there are exceptions.
This whole issue makes me rant. Sorry. L
I didn’t see your post as a rant, but rather an informed complaint about how too many people treat the looks of a breed with higher regard than an individual animal’s health. It’s shameful and it needs to stop.
Thx. L
Hear, hear, Linda.
I’m proud to be from Kalamazoo, MI, home of the UKC:
http://www.ukcdogs.com/WebSite.nsf/WebPages/LrnAboutUKC
Though I get my dogs from the pounds. Mutts rule!
Being a cheap person, I never really understood people who spent hundreds of dollars on a special breed of pet when you can get one from the pound, with all its treatments, for around $75 bucks where I live.
What? You don’t don’t like puppies?
I’m teaching this guy to use the light sabre as he takes on the neighbourhood cats…
http://eheffa.zenfolio.com/img/s1/v20/p1011000962-4.jpg
😉
-evan
Awwww. I had something that looked just like that when I was a kid. OK, it was a pure-bred poodle. Fads were us, or at least, were my Mom. Plus, she wanted a “neat” dog.
Turned out to be a wonderful dog.
Thanks Diane.
Well yes, this is a pure-bred Miniature Poodle. ( I hesitate to admit that with this crowd.) we tend to be allergic to most dog dander so this breed is just one of a few options we could live with. In this case the ‘pure-bred’ distinction gives us some predictability. As it turns out, I shed more than the dog does.
He’s a great little Guy.
– evan
You can view the “Pedigree Dogs Exposed” documentary here
youtube.com/watch?v=GhXHFOrBbEc
After watching it earlier this year I started noticing how deformed some of the dogs in the neighborhood seem. It is pretty sickening what some breeds of dogs have come to.
I have a serious question to pose, and considering the level of education on this site, I expect someone here is capable of a scientific answer. (I don’t remember where I heard the question, but I thought it an intriguing one.)
Ok, so I know that all dog breeds descend from the gray wolf, no matter how different a teacup poodle and bull mastiff seem. What if researchers were to find a fossil similar in size and shape to a teacup poodle, and were also to find a fossil resembling that of a bull mastiff? Would they think these fossils were from the same species? Could the researchers infer that these fossils were, at least, closely related? What’s the margin of error in such a case?
Caveat: I’m not a creationist, nor religious. There’s no ulterior motive in this question. I’m just curious for an answer.
I’ll give this one a try, since I work on speciation. If people found a fossil of those animals from the fossil record (not simply remains from today), they’d certainly classify a teacup poodle and a bull mastiff as different species, though they’d of course infer that they were both canids.
But there’s a difference from judging species status from morphological differences from the fossil record and from looking at present day species that resulted from artificial selection. If the poodle and the mastiff had evolved in the distant past from a common ancestor, like the African wild dog and the gray wolf themselves, it would have taken millions of years to achieve this divergence. And the byproduct of those millions of years of divergence would be the accumulation of numerous genetic differences that could produce reproductive isolation (e.g. hybrid inviability or sterility) were these “fossil” species to encounter each other. It’s that inferred reproductive incompatibility that would make us call them different species. Taxonomists do make judgment calls based on morphology in fossils, as they must, but these can also involve inferences about whether the fossils would have been reproductively compatible when alive. (For instance, if two different but related fossil forms were found in the same area and show no overlap in morphology, that’s a good sign that they didn’t hybridize).
In contrast, domestic dog breeds were all produced by strong artificial (human-imposed) selection in the last ten thousand years or so. These changes produced rapid divergence of appearance, but probably involved only relatively few genes compared to how such divergence would take place in nature. Strong selection picks out genes, like achondroplastic dwarfism genes, that have large effects, while in nature differences usually involve far more genes. Since the strength of selection imposed by humans is much, much stronger than that seen in the wild, dog breeds today (even ones as different as poodles and mastiffs) differ by many fewer genes than genuine dog species in the wild that are more similar in morphology than some dog breeds (foxes vs. wolves, for instance).
Since reproductive isolation is, we think, simply a byproduct of general genetic divergence, dog breeds today, which differ by relatively few genes, can all interbreed. If they were fossils, though, they would have differened by many genes and would almost certainly, as a byproduct, be reproductively incompatible.
This is a good question, and one that comes up every year when I show the students my dog-breed chart. I hope this sheds some light on your question.
Wow. I was expecting, at most, maybe a citation or reference, which would’ve been great. Thank you for responding at length, sir.
I never realized that difference between artificial and natural selection (i.e., it comes down to the differential amount of genes the two processes act upon). But now that I think about it, that makes perfect sense: artifical breeders are always looking to “benefit” one or a just a few traits, be it dogs or plants.
Again, from a student of biology, I thank you.
This is a really great answer. I had a similar question: how is it that such profound morphological changes can occur in dogs while they remain a single species, yet in nature such changes would almost certainly result in reproductive isolation? I finally feel like I finally have a satisfactory answer to a question that’s always bothered me 🙂
What a fantastic explanation!
I do have a question though: is it a fact that all species of dogs can interbreed? Common sense seems to dictate that these fellows, at the very least cannot. Even if it were genetically and embryologically (can I use the word that way?) possible, you can’t ever expect that these two would want to or be able to copulate successfully.
Doesn’t it make more sense to think of modern dogs as a ring species? If indeed great danes and chihuahuas cannot interbreed, then we need only kill all the breeds intermediate between the two in order to say that the two are completely separate species.
Given that both dogs in that picture appear to be female, I think it’s a pretty safe bet that those two cannot interbreed.
But it’s not obvious to me that a male chihuahua would not or could not impregnate a female great dane. And I’d certainly expect any offspring of such a union to be viable.
Yes, absolute–you can think of them as a ring species, which is precisely what I had in mind. If you put a member of every breed in a big kennel, eventually they’d all homogenize to some mongrelized form. And, as I show in the book Speciation I wrote with Allen Orr, there really aren’t any airtight examples of ring species in nature.
I guess chihuahuas and Great Danes wouldn’t be able to interbreed if you stuck both types in a kennel.
Jerry: Great, thanks for answering that. I’d be interested to read more about the problems with the ring species examples in nature (perhaps I’ll check out your book!) I’ve always been under the impression that the Herring Gull and Ensatina salamanders examples were good ones.
Gregory: I’m not sure how a male chihuahua would mount a female great dane. It seems physically very unlikely, so I don’t think you can fault me for asking for evidence for the claim that it’s possible. If it weren’t possible, it would be just another example of non-genetic reproductive isolation.
There are known cases of unions between Great Danes and very small dogs. Mating can occur if the female lies down.
Dogs don’t need to mate naturally these days – and indeed, some can’t. Breeders can and do offer a helping hand, either via AI or…
http://celticpride-bulldogs.co.uk/cradle.htm
Jemima
I’m not a taxonomist, but shouldn’t the burden of proof be the other way round? Seems to me that two genetically compatible populations ought to be considered the same species unless reproductive isolation has been convincingly demonstrated, not just conjectured. Our failure to imagine how they might interbreed seems like a poor basis on which to make a claim of speciation.
That’s why I didn’t. I asked if it was indeed a fact that all species of dogs can interbreed. Apparently it’s not.
The hell you can’t. If you doubt me, find a chihuahua in heat and take her for a walk…
Just a layman here, but I strongly doubt it
I note that some dinosaur fossils that were thought to be of different species are now thought to be the male & the female morphs
Similar problem with creatures who change shape [& size obviously] as they mature ~ and I’m not even thinking of insects here
Sorry for using ‘morph’ can’t think of a better word today
I look forward to better answers here 🙂
Haha, I just read a nice book on dinosaur evolution… its actually pretty fascinating. I love that T. Rex and Velociraptor are close relatives of birds, and that all the dinosaurs are descended from bipeds, and that T. Rex and velociraptor are close cousins to birds.
The thing about dogs is that I bet there are a lot of very basic components of their morphologies that even the most derived breeds share with each other, versus more distantly related carnivorous mammals like cats. Since a lot of what we have been selecting dogs for is size, coat color, and skull shape, I bet that there are still a lot of similarities in the overall types of bones the dogs have. Various holes in the skull, grooves in the pelvis, the number and layout of hip, wrist, and other types of bones would be similar.
A lot of the animals and plants we’ve domesticated from nature (perhaps even most?) have been altered to the point where a)they bear little resemblance to their natural forebear, and b)they would not long survive without our intervention. Oh, and in many cases c)they have acquired some detrimental traits in the process, which are balanced by what we perceive to be positive traits. In WEIT, Jerry uses domestic turkeys as an example, which couldn’t even breed without our help.
The question is, how far is too far? Are aesthetics the line that should not be crossed? If so, we seem to have passed that point thousands of years ago.
The question is, how far is too far? Are aesthetics the line that should not be crossed?
The line that should not be crossed is where aesthetics are to the detriment of the species, either reproductively, or during the life of the individual. In dairy goats, the ears of Nubians (the breed with the long, floppy ears) are supposed to reach the tip of the nose. This does not affect the well-being of the goat. Similarly, in LaManchas (the breed with the tiny ears), external ear leathers are not supposed to be more than an inch long in does, and are supposed to be true “gopher” ears in bucks. You can easily see that the aesthetics don’t affect well-being.
But, in dogs that are supposed to have flat faces, where respiration is difficult, that is a different matter. Jerry put up a posting a couple of weeks ago about race horses, showing the overly fine bones in the legs, which cause many of them to be injured severely. I posted earlier in this thread about aspects of the breed standard of African Pygmy goats that cause reproductive problems, often causing the death of the dam.
Proponents of extreme “style” need to be asked why the “style” is more important than the animals. L
I have encountered small populations of various fishes which, I suspect, have been small for a number of generations. They should, therefore, be highly inbred. However, I noted no problems with exposure of deleterious recessive genes, etc. I wonder if these represent situations where the recessives have been lost, and are not present in the small population.
If some catastrophe wiped out all dogs except Great Danes and Minature Poodles, we might decide that there were two species of domestic dogs.
If traits are fatal, they don’t continue. L
They can if they’re recessive – if the heterozygotes (individuals with one mutant copy, one normal copy of the gene) are not diseased. Even a lethal variant can persist in a population through heterozygotes. If two heterozygotes breed, they have a 1 in 4 chance of each passing on the mutant copy of the gene, causing the recessive state to be expressed; but unless this happens, there is no selection against the mutant copy, since there is no disadvantage to being a heterozygote.
That’s anecdote.
“American Cocker Spaniel – Wikipedia, the free encyclopediaen.wikipedia.org/wiki/American_Cocker_SpanielCached – Similar
It is a spaniel type dog that is closely related to the English Cocker Spaniel; the ….. prone to canine epilepsy and the related condition known as Rage Syndrome. … a normally placid dog to engage in sudden and unprovoked violent attacks. …”
I didn’t see one of the more serious Cocker breed problems. An epileptic like seizure called Rage syndrome where the dog “engages in sudden and unprovoked violent attacks.”
I’d be real careful getting this breed with small children or other small pets. A few times a year, children are killed by the family dog.
My aunt’s over-bred, champion-line Cocker had those rage attacks. I effing hated that dog. I used to call him “Bufferin” (his name was Buffy) because he was such a headache.
Until I read what you wrote, I thought it was just Bufferin.
What’s worse is the bigger breeds subject to the same condition. St. Bernards, in particular.
So this explains why I haven’t seen any cocker spaniels since the pair our neighbors had (Rusty & Martha) I was a kid. Now I understand that what I really mean is that I haven’t seen any ’41 Cocker Spaniels since I was a kid.
A lot (or some anyway) of breeders are trying to get away from aesthetics that are deleterious.
The Persian cats have been bred for flat faces which causes all sorts of problems with breathing, eating, and tear ducts. They call them “extremes”.
There is a subbreed that doesn’t go for that anymore. IIRC, they are called classic.
I got an old cat from the animal shelter who turned out to be a Persian show cat. She doesn’t have the flat face at all or any of the problems.
I always try to get mixed breeds but she is an OK cat.
There are definite problems with inbred cats: http://mlkshk.com/r/70IH
I don’t have a problem with dogs. I just disagree with their anti-cat politics.
And yet that’s one reason I like them — my dog keeps the cats out of the back yard, and this keeps the fence lizards from all being eaten by the subsidized predators. It even permits the towhees to nest under the hedges once in a while. Cats are nice enough, but should be kept indoors, IMO.
“No species has a closer relationship with humans.”
I expect there are some eyelash mites and crab lice (not to mention gut bacteria) that would take issue with that statement.
Good catch. But I think he’ll fall back on that was being ineffable, or metaphorical, or allegorical, or some such… Because, when in doubt, loosing or wrong — change the rules of the debate… 😉
Are all dog breeds truly able to interbreed, for example if a chihuahua was artificially impregnated by a great dane, would we truly expect the pregnancy to succeed?
Also, I’ve read that dogs have less genetic variation than wolves, which I guess is understandable if all dogs are descended from a handful of wolves. But are there any genes unique to dogs that aren’t seen in wolves? This would be powerful evidence that mutation and selection can produce new genetic information.
But don’t we have to look over the whole population to establish existence of barriers? You can stage dog sizes over pairs until you eventually breed descendants of chihuahua and great dane with each other. So are they really genetically isolated?
I understand there’s a gene variant for melanism (black coat colour) that originated in dogs and was later transmitted back to wolves. That’s a gene variant, of course, not an actual new gene – but I suspect that’s what you meant. 10,000 years is a very short time for a genuine new gene to appear AFAIK.
Yes. But to be humane, you’d sure want to dam to be the Great Dane, not the chihuahua!
I think the 2011 spaniel is grotesque. The 1892 animal is a gorgeous and practical beast. It’s just wrong that breeds are kept for the sole amusement of humans even when the animal suffers so much because of the inbreeding. I think I’ll stick to my nondescript strays.
The trend now, at least in Australia, is to breed dogs for what they were meant to do originally, to reverse the excessive show judge mediated changes. Yes, it is show judges who spur breeders to change dog breed characteristics. I have seen it in Miniature Pinschers, a breed of rodent hunting dogs of older pedigree than the Dobermann Pinscher, yet judges preferred that the Miniature Pinschers to actually look like miniature copies, toys, of Dobermann Pinschers. This has lead to breeders changing the snout of the Miniature Pinscher to complete this judge mediated idea.
Sense is creeping back into dog breeding and dogs like those with pushed in snouts will eventually be able to breathe without difficulty, German Shepherds won’t get hip displasia and Dalmatians won’t go mad.
I like cats fine, but cat people are devils in carnate.
My mother had a Springer Spaniel when she was a girl. It was still alive until I was five.
It was a great, athletic dog. But now the AKC is starting to ruin that breed too. Today they’re about to where the cockers were in the 1950s.
Shame really. The modern Cocker Spaniel is a moronic pile of crap. I have you to meet one of these over-bred clowns and walk away with a positive impression.
My students often ask me whether dog breeds are separate species, and I say “no” because of this reproductive compatibility.
Maybe you shouldn’t then. Great Dane stud and Pomeranian bitch are not exactly compatible. Even with artificial insemination there would be countless problems with pregnancy, whelping and maybe even with the offspring viability.
Yeah, but the opposite combination works, so how is that not interbreeding?
It’s not the interbreeding in a sense of species concept anyway. Because that one specifically stipulates “in the wild”. In the case of dogs, in the wild means no artificial insemination. Without it, good luck observing Pomeranian successfully mounting Great Dane.
I saw a documentary recently about how the english bulldog and other breeds have been bred into a genetic mess. Time for reform in dog breeding.
That’s probably the Pedigree Dogs Exposed documentary from the UK (possibly repurposed and revoiced for US TV which happens a lot) which the main article references. It’s all on YouTube: http://www.youtube.com/watch?v=GhXHFOrBbEc
Isn’t it established that dogs are *not* derived from wolves (at least for the most part), and more closely related to Indian prairie dogs or some such? Has there been much sequencing to put the question to rest? Will this new study definitively address the origin of domesticated dogs?
It appears that they’re *only* descended from the grey wolf.
Ok, well here is a counter-case presented (with references) by a SciAm writer:
http://darrennaish.blogspot.com/2006/10/controversial-origins-of-domestic-dog.html
Presuming your assertion justified, when, where, and under what circumstances did the dog become domesticated and diverge from the grey wolf?
I had an uncle who used to claim that all blue-eyed white cats were deaf. Could anybody verify that, or is it even true? Would that be a result of pleiotropy?
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How interesting. I have a very old book of dog breeds, and it’s remarkable to see how different the dogs are, the observations in this article are so accurate!
It’s sad, really. I’d never buy a purebred dog.
This is true of this breed and other types as well. When I was a teen we bought a Cocker as a pet and were so taken in with them that we bought 2 more.
At the age of 4-5 they all had genetic problems surface and they had no seeming relation to one other through pedigree. Blindness, hip problems, compromised immune system, detached retinas, tumor growths, constant vet visits. All these dogs only lived to get around 7 years old and had to be put down due to their deteriorating and feeble condition.
On the opposite end of the spectrum our mix breed dog Ginger that we had gotten from the animal shelter when I was 5 and my brother 3 lived to be 25 years old. Her only problems arose when she was nearing 20 years (cataracts,arthritis) which is expected in a dog considered so ancient.
It’s interesting that you would position dogs and breeding in support of evolution being true, whereas I have always considered dogs to be a stumbling block to the theory.
Dog breeding has indeed produced wide variations in the appearances and physical characteristics (height, weight, etc.) of dogs as various breeds were the product of characteristics breeders desired. However, throughout the 15,000 years or so since dogs have been domesticated, they have yet to evolve into a separate species.
Dogs can still mate with wolves and bear fertile offspring, which is the definition of what constitutes a single species. We can label dogs as a subspecies of gray wolves as a matter of convenience. The fact remains that they are still wolves.
No one denies that superficial differences within a species are a result of either deliberate breeding or natural selection, such as the tone of a human’s skin and where he or she or his or her ancestors originated. The issue is what exactly is the mechanism that enables one species to evolve into another incapable of breeding with the parent species.
FYI, there are those that are breeding for the old style cocker of the 1940’s or “field type” for hunting, trialing & hunt test purposes. Over the past 20 plus years of training with (American) Cockers, that birdie instinct is still there, even in the show lines. I have found, the more I bred back to the old style cocker, the more they looked like the field-bred English Cocker of today. Note the red (American) Cockers on the top of my shutterfly page, they were bred in the 1990’s by me, and were good bird dogs. I hate to groom dogs, I like the natural “field or sport coat” on american cockers, they are out there, but one has to do a lot of searching if you want one.