Culture: Science & History
Canine Origin Story
Researchers have identified the origin of cattle, horses, pigs, sheep, camels, ducks, chickens, cats and goats. But the genesis of the domestic dog, our oldest companion and the most varied, numerous and widely distributed domestic animal on the globe? We’re still trying to figure out that one.
The study of patterns of diversity is called systematics, and it is a critical subdivision of evolutionary biology. Systematics researchers (earlier called naturalists and taxonomists) sort out species’ genealogical relationships and estimate the points at which populations diverged from one another. Traditionally, they relied on observations of differences in stable physical traits like teeth, skulls and sometimes fossils. More recently, genome-wide comparisons have been used to provide detailed information about species relationships, including the question of when and where wolves became dogs.
Canis lupus familiaris exhibits the most variability in shape, size, behavior and temperament of any mammal species living on earth. About one billion dogs, a population larger than any other domestic subspecies, roam the globe. Canine fossils, some dating to as long ago as 36,000 years, are found on every continent except Antarctica.
Add to that the unusual phenomenon that extreme variation can occur in as little as one generation—a sort of evolution at hyper speed—and we begin to understand why classifying domestic dogs has challenged many of the taxonomical systems that have been used to make sense of Canidae, a family that includes wolves, jackals, foxes and dogs.
Historically, as far back as the fourth century BCE, theories of the descent of animals were the product of using philosophical approaches to relate organic life to the history of time. At first, fundamental ideas about species-change involved sorting out living beings by means of their common essential properties. Philosophers wanted to know how organic life forms were related, not where they came from.
The Greek philosopher Aristotle (384–322 BCE) endorsed the idea that natural beings were always here and always would be. He commented on the dog’s origin, not in respect to the animal’s continuous chronological past but rather, in terms of breed creation. In his view, the dog that nature created was bred to the fox to make small dogs and to bears to make big ones, perhaps making the point that breeds (although he was mistaken about cross-species hybridization) were created by humans. Still, in the Aristotelian view, dogs always existed.
As time went on, the earliest naturalists came to understand that species were related in more complicated ways, and began to devise orderly classification systems. The bigger picture of life, however, was explained within a theological context: a specific act of an omnipotent creator transformed all living things whole and complete. The revolutionary notion that every animal might not be a singular divine creation didn’t materialize until the late Middle Ages, a contradiction that had to be explored hypothetically to avoid conflict with religious doctrine.
In the late 18th century, France’s leading naturalist and the father of paleontology, Georges Cuvier (1769–1832), introduced a new way of looking at life and death. Although he was firmly in the camp of divine creationism, he theorized that animals eventually went extinct.
Earlier, 16th-century English cleric Edward Topsell (1572–1625), author of The History of Four-footed Beasts, whose worldview was defined by fire-and-brimstone religion, based his categories on morality. This was not as much of a stretch as it might seem from today’s vantage point; during Topsell’s time, people had real reason to fear wolves. For them, the predatory wolf and sagacious, noble dog provided excellent examples of two moral extremes.
Domesticated farm livestock had derived from prey species, and no other large predator had (or has) been domesticated. So it seemed illogical that the gentle, devoted dog could have evolved from the wolf. As one writer lamented, “How could such a noble animal as the dog be derived from the likes of the wolf? If evolution were true of dogs and wolves, wouldn’t every beast choose to live the noble life?” Indeed.
But as Darwin later observed, if organic beings didn’t possess an inherent tendency to vary, humans could do nothing. Unlike bears and lions, wolves, for reasons still scientifically unclear, possessed the variation necessary for the creation of the multiple hundreds of dog breeds recognized today.
The Shape of Things
Imagine how frustrating it must have been to try to make sense of how dogs were related and where they came from based on their appearance. Travel the world over and a cat will usually look like a cat, but dogs were a vexing contradiction.
The lack of understanding of the complexity of canine morphology made it difficult to unravel relationships among the ever-increasing numbers of dogs and dog-like animals being discovered on far-away, previously unexplored continents. In the Americas, many were likely Old World breeds introduced by European explorers, eventually returned to a feral state. Over time, they interbred with American Indian dogs, wolves and coyotes, defaulting to pariah-type dogs—a catchall term for semi-feral, free-ranging canines. But a misunderstanding of the distinct differences between wild, tame, domestic and feral dogs added to the confusion about how Canidae should be classified.
The father of modern taxonomy, Carl Linnaeus (1707–1778), assigned dogs both wild and domestic to groups based on their anatomy (muzzle, jaw, ear shape), tail carriage (dog tails curve when relaxed, wolf tails don’t), hair texture, limb length and behavior, criteria that are still used today.
Linnaeus’s contemporary, Georges- Louis Leclerc, Comte de Buffon (1707– 1788)—of whom Linnaeus sniffed, “Always eloquent, often incorrect”— suspected that changes in canine morphology were influenced by environmental pressures, such as climate. But, like his colleagues, Buffon did not consider change within an evolutionary context.
Dividing dogs into categories based on skull shape was Cuvier’s idea, and although his forward-thinking approach to paleontology and the history of organisms would seem to make him an advocate for evolution, he was not. Cuvier’s interest, after all, was in a species’ demise, not its origin. Nevertheless, his contributions greatly influenced Charles Darwin.
Darwin (1809–1882) believed that the dog had multiple origins: from wolves, jackals and at least one South American species. He supported the latter by referencing his observations of dogs in Patagonia who swam underwater and an unusual dog he had seen in Central America. He also advanced the idea of multi-regional domestication.
Darwin further imagined that these small populations of “inferior” native dogs were eventually supplanted by the incursion of more robust dogs introduced by Europeans, an analogy he used to demonstrate the idea of “survival of the fittest.”
Although the fundamental theory of origin is attributed to Darwin, other taxonomists previously proposed similar ideas and connections, including Jean-Baptiste Lamarck and Alfred Russel Wallace. Unlike Lamarck and Wallace, however, Darwin suggested that the evolutionary process occurred through natural selection.
Although Darwin used the breeding of dogs and other artificially selected animals as analogies to explain how natural selection worked, dogs continued to be an untidy group of animals —a puzzle that science has began to unlock by the use of genome-wide sequencing.
In the Genes
Once scientists discovered methods to explore origin at the molecular level, they began to test these historical theories. As early as the 1970s, research papers were published suggesting that dogs may have been derived from several different gray wolf populations, and that canine domestication may have happened much earlier than the fossil record’s 15,000 years ago. By the late 1990s, geneticists worldwide were working together to build a comprehensive map that would chart the evolutionary journey of domestic dogs.
The path was not smooth. Differences of opinion erupted and criticism of research methodologies undermined a delicately balanced collaboration process. Numerous studies argued for canine origin in places as diverse as East Asia, Mongolia, Siberia, Europe and Africa, with timing varying from somewhere between 15,000 and 135,000 years ago. Archeologists who’d studied ancient canine burials were relegated to the sidelines, their fossil records dismissed as “old school,” which created further dissention. Researchers struggled to find common ground, but without much success.
The debate ramped up in 2013, when UCLA evolutionary biologist Robert Wayne and his team published a comprehensive set of data suggesting that dogs evolved from a group of European wolves, now extinct, somewhere between 19,000 and 32,000 years ago.
Two years later, Peter Savolainen, a molecular biologist, and his colleagues at the Royal Institute of Technology in Stockholm published convincing results indicating that dogs originated in China, south of the Yangtze River. They estimated that this dog population split from wolves 33,000 years ago.
Both teams were sequencing DNA. Why were their findings literally all over the map?
Savolainen’s research team analyzed DNA samples from living global dog and wolf populations, then tracked DNA from least to most diverse, going back through time. The general rule is that the older a population of animals, the more diversity it has in its genome, which is a hallmark of ancient origin.
Whether these animals represented the first domesticated dogs or, rather, dogs who migrated to the region from elsewhere and split off from a more ancient dog population, is unresolved. Fossil remains of an ancestral and probably extinct population of wolves that would have been indigenous to the area would seal the deal, but researchers have yet to find them. As Savolainen notes, “We have access to some archaeological samples we are about to analyze. However, there has been quite little archaeological work, especially on animals, in the region.”
While Savolainen and his colleagues worked backward in time, Wayne’s group worked forward, tracking ancient DNA collected from prehistoric bones of wolves and wolf-like dogs, then measuring decreasing genetic diversity. As DNA becomes less diverse, it points to animals transitioning from wolves to dogs. A dead end indicates that a lineage became extinct in that particular region.
Wayne’s team sequenced ancient DNA on canid skulls and bone fragments discovered in present-day Siberia and the Czech Republic dating to between 27,000 and 33,000 years ago. The physical characteristics of the skulls—wider muzzles and foreshortened jaws—suggest that these were ancient proto-dogs, not wolves. The canids may have looked similar to today’s Arctic breeds (for example, the Siberian Husky and the Greenland Dog), but were probably much larger. Although their findings were met with skepticism, the team said their data showed that domestic dogs originated from different wolf populations at different times in different places, in a series of starts and stops. And, they added, living dogs are more closely related to ancient extinct wolves than they are to modern wolves.
In an interesting twist, Wayne’s findings reignited the theory of parallel and multi-regional proto-domestication, an idea that Darwin introduced in the 19th century and one that’s gone in and out of favor since.
Both studies have detractors. Some claim that diversity in Savolainen’s ancient dog population is a result of admixture with European dogs as people traversed the Silk Road. Those who criticize Wayne’s study maintain that he has no solid proof that the ancient bones he’s studying are definitively wolf or dog. Additionally, critics say, his study is geographically biased because he excluded samples from dogs in China based on his position that there are no ancient dogs there.
Although the two studies point in very different directions, Savolainen and Wayne may both be right. It’s possible that dogs were domesticated multiple times in different regions, and that most lineages died out when humans were faced with overwhelming challenges, like climate change. Their findings aren’t mutually exclusive.
Crunching the (Very Big) Numbers
One reason for the disparities, according to Oxford’s visionary evolutionary biologist Greger Larson, who was a part of a team that successfully mapped the origin of the pig, is that scientists studying the dog are not including enough ancient DNA in their studies.
Larson and colleague Keith Dobney, an archaeologist at the University of Aberdeen, had the idea to bring together all the evidence collected to date, find ancient canid specimens from museums, apply state-of-the-art technology and create a database bigger than anything produced before. All they had to do was convince scientists to agree to work together.
Fortunately for canine genetics, Larson was able to sell the idea that more cooperation and collaboration improves the outcome. As chief mediator and conciliator, and supported by substantial funding, he has persuaded more than 50 influential canine evolutionary scientists to join the project. Team members include archaeologists, paleobiologists, anthropologists, zooarchaeologists, paleogeologists and others.
The purpose of the study, which began in 2013 and is slated to wrap up this year, is to combine ancient DNA analysis and geometric morphometric techniques and apply them to archaeological canid remains. This, he suggests, will directly address where, when and how many times dogs were domesticated.
Geometric morphometrics, the study of form in two or three dimensions, is a powerful new way to visually quantify evolutionary relationships. It does this by correlating thousands of geometric points that identify exact places on bones—specifically, points of evolutionary significance that differ between very closely related animals such as the wolf and the dog.
Using a special camera, researchers take hundreds of 360-degree photographs. Software then transfers the pictures to a three-dimensional computerized image that emphasizes a set of tightly defined, very specific points on each bone. The process results in holographic- like images that show domestication in progress through space and time, much like a movie.
Additionally, scientists are isolating and examining ancient DNA collected from museum specimens, looking for changes in the degree of genetic diversity over long periods. This will provide a comprehensive overview of the wolf-to-dog transition from the beginning to the present.
No individual genetic fragment of DNA says This is a wolf or This is a dog. Rather, scientists tease the two apart by looking at strands of DNA and identifying and measuring similarities and differences. As differences become more extreme, the separation between wolf, proto-dog and, finally, dog is suggested.
The team hopes to isolate genetic fragments that can be linked to minor changes in the geometric morphometricimaged samples. Combining the two techniques will tell a deeper, more layered and detailed story about canine domestication.
Larson expects to analyze up to 7,000 specimens representing wolves, incipient canids and domestic dogs. “We’re taking samples from all over the world, sources in not only museums but from private collections, too. Curators are very agreeable when we ask for permission, and they’re usually very happy to have us take photos and DNA samples. They help us, and in turn, we provide more information for their collection.”
While Larson is enthusiastically optimistic about the outcome of this unprecedented project, some scientists not affiliated with the study think the findings will only add to the existing mishmash of conflicting hypotheses. But that’s how science works: come up with an answer and you invariably end up with a lot more questions.
The ongoing search to understand where, when and how many times dogs were domesticated continues to be a topic of active scholarly exploration. Besides the millions of dog lovers who are curious about the roots of our affectionate and unusual cross-species relationship, substantial scientific issues are at stake, issues that may profoundly alter the future of evolutionary theory.
Read about new developments.
Good Dog: Studies & Research
How Closely Are They Linked?
I’m interviewing a new client whose dog tends to bark and charge and nip the heels and dan- gling hands of retreating strangers. Her dog is smallish and stocky, with a coarse, medium-length coat of mottled blue-gray, black, white and brown. His nose and ears are pointy. While I reassure her that his behavior actually makes sense from his doggy point of view, a little voice in my head whispers, “What did she expect? She got a Cattle Dog.” I have little difficulty discounting the client’s own plaintive claim that she’s had Cattle Dogs all her life and this is the first one who’s acted this way. “You were lucky until now,” my little voice says, assuming those dogs were somehow the exceptions. But when another client complains that his large, square-headed, short-coated, yellow dog is growly around his food bowl, I take his statement that “none of my other Labs have done this,” at face value. The current dog is clearly the exception. After all, my little voice says, “everyone knows Labs love people.”
My little voice is probably wrong.
So why not use breed as the way to choose the particular puppy or dog who’s likely to help us fulfill the dream of taking a perfectly behaved, friendly dog to cheer the lives of people in nursing homes, be endlessly tolerant with our kids or have the kind of indefatigable enthusiasm for retrieving that makes a good contraband-sniffing dog? How about using breed stereotypes to guide public policy decisions on whether some dogs are more likely than others to present a danger to people, or simply to assess whether that dog coming toward us means us good or ill?
Turns out it’s not that simple.
And even reliable identification of the ancestry of a mixed-breed dog by itself wouldn’t help us predict an increased likelihood of known, genetically driven traits — say, the blood-clotting disorder that plagues Dobermans or the heart defects of Cavaliers. The parents of any mixed-breed dog have, by definition, waded out of the closed gene pool that makes purebred dogs such fertile ground for genetic research. The inevitable inbreeding of purebred populations, combined with a phenomenon called genetic drift, gradually decreases overall genetic diversity; more and more animals have fewer and fewer variable traits, including characteristics that aren’t deliberately selected for or against. But as researchers found with a colony of wolves in Sweden, even inbreeding so severe that it causes infertility can be reversed by the introduction of just one outsider. So, if we could demonstrate such a thing as “acting like a Beagle” or “acting like a Basenji,” there would be little reason to expect either one from the offspring of a Beagle/Basenji pairing.
But what about those purebred Basenjis and Beagles and Cattle Dogs and Afghans and Golden Retrievers? Can’t we expect them to behave consistently in ways that resemble the work at which they were once selected to excel?
Yes and no.
And yet, every single one of her ancestors, going back scores, perhaps even hundreds, of generations, was hyper-motivated to chase. They would not have had the opportunity to reproduce otherwise. Racing Greyhounds are bred for two things only: a keen inclination to pursue small, fast-moving furry things and the physical ability to do it at great speed. Racing industry insiders estimate that only about 70 to 80 percent of the dogs who result from this ruthless selection process are keen enough to race. Now, a 75 percent incidence of a trait sounds pretty high. You’d certainly take those odds in Vegas at the roulette wheel. But this is a trait that’s already extremely common across the species; it is, in all likelihood, the most widespread of the predation behaviors of hunting, stalking, chasing, killing, dissecting and eating first observed and described by the famous wolf ethologist, David Mech. Most dogs already do this. If you take more complex behaviors that are actually selected against in the wild, like compulsively fighting other dogs and failing to respond to the doggy body language equivalent of “crying uncle,” for example, your odds of reliably producing the behavior through artificial selection go down dramatically. This explains how so many of the so-called “game-bred” dogs from fight busts (like the ones rescued from Michael Vick’s fighting operation) have gone on to live companionably with other dogs as relative couch potatoes in normal homes.
Reliably increasing the likelihood of complex behaviors through selective breeding isn’t easy. And racing Greyhounds are one of only a handful of dog breeds where this is still even attempted. Since the advent of modern purebreds in the late 19th century and the subsequent closing of breed registries, selection criteria have focused almost exclusively on appearance. Qualities of temperament are sometimes mentioned, although not in ways that can be practically applied in the show ring, where — as biologist Ray Coppinger has pointed out — the behavior required is standing, and to a lesser degree, trotting alongside a handler. Most purebred dogs come out of this selection system.
So these days, when people look fondly at the breed they fancy or angrily at the one they fear and say to me, “They’re not like other dogs,” I remind my little voice to recite, “Well, actually, they kind of are.”
Good Dog: Behavior & Training
In her new book, Pit Bull, Bronwen Dickey thoughtfully examines the history, stereotypes, fiction and societal worries surrounding a breed that was once thought to be an American icon. In this excerpt, she scrutinizes the science behind a misunderstood and complicated behavior.
The Victorian dog-show mania of the mid-nineteenth century not only created hundreds of new breeds, but also created two possible categories of bloodlines within many of them: working bloodlines, in which behaviors were most important, and conformation or show bloodlines, which prioritized appearance over behavior. The “washouts” from the conformation lines usually went on to pet homes. The dramatic increase in the number of breeders also allowed for more physical and behavioral variation within each breed, with the most popular dogs also being the most varied. Today, Labradors from American show lines are much shorter and fatter than they were even twenty years ago, while Labradors from British field lines are leaner and leggier. Dogs from these two strains may not only look different, they may also have drastically different behavioral profiles.
When breeders stop pushing, the car rolls back down the hill, and canine behavior drifts back to the middle. Exaggerated traits that are not selected for and not adaptive will mellow out and disappear over time, which is what appears to be happening in both the American and European dog populations. The overwhelming majority of modern dogs live as pets, rather than workers. Great Danes are no longer used for boar hunting. Siberian huskies do not pull sleds. Rhodesian ridgebacks do not bay lions, and most dachshunds will never see a badger, let alone kill one. Rather, these animals are physical reminders of the way the world once was. As the historian Scottie Westfall says, “Dogs are artifacts.” Though it is common to attribute a dog’s behavior to the task it was historically “bred for,” many of us fail to consider that most of today’s dogs are “bred for” the work of being companions, and have been for many generations.
In 2005, Kenth Svartberg, a zoologist from Stockholm University, collected data from more than thirteen thousand dogs from thirty-one breeds that had been subjected to a standardized behavior test and sorted them according to behavioral traits such as “playfulness,” “curiosity/fearlessness,” and “sociability.” After analyzing the data, Svartberg and his colleagues found that there was “no relationship . . . between the breeds’ typical behavior and function in the breeds’ origin.” He did, however, find that dogs from working lines (not breeds, but lines) retained more of their historical working traits than dogs from show lines, leading him to conclude that “basic dimensions of dog behavior can be changed when selection pressure changes, and . . . the domestication of the dog is still in progress.”
Pit bull breeds are not exempt from this trend. Unlike pointing or retrieving, both of which increase a dog’s ability to feed itself and its offspring by hunting, fighting isn’t one behavior but a complex series of behaviors that put the animal at tremendous risk. As highly social creatures that negotiate and renegotiate their relationships over time, most dogs depend on shared resources for their survival. If removed from human society, a dog that indiscriminately attacks or kills its own kind doesn’t live very long. While it’s certainly possible to breed for certain types of aggression (toward humans or other animals), it’s much harder to breed dogs that match the profile that fighters say they want: an animal that is indiscriminately accepting of humans, selectively reactive around other dogs in a specific environment—the pit— but tolerant of dogs outside of it, one that “doesn’t signal its intentions,” and also “doesn’t feel fear or pain.” They may as well be describing the American unicorn terrier, because these are all genetic dead ends.
No researcher has yet located an “aggression gene” or a set of aggression genes, despite years of genomic analysis. While conducting his research at Bar Harbor, John Paul Scott considered aggression “a poor scientific term [that] chiefly functions as a convenient handle to relate phenomena described in more objective terms to practical human problems.” At best, today’s scientists can only make educated guesses about certain components of canine reactivity, like the startle reflex (which multiple studies indicate is heritable) and individual pieces of the agonistic repertoire (freezing, fleeing, defensive postures, vocalizations, etc.). But this requires that researchers clearly define and isolate the behaviors they are observing, which is always a challenge. It’s possible, for example, that what was once called “rage syndrome” in certain lines of the English springer spaniel and English cocker spaniel is not one condition but several that were mistakenly grouped into one category. A few studies in mice and dogs have shown that disruption of the 5-hydroxytryptamine (5-HT) receptors in the brain, which regulate the neurotransmitter serotonin, may be linked to specific types of impulsive aggression, but in both animals and humans, the 5-HT receptors can be damaged by stress and trauma that occur both in utero and after birth. Yet even these possible neurological links have been observed only in dogs from tightly closed gene pools. They are not widely passed from dog to dog in an open breeding system, like the passing of a disease.
“Let’s assume that you and I are working to breed the most dangerous aggressive fighting dog in the world,” Kris Irizarry, the geneticist at Western University, told me. “And we want this dog to turn and attack any human being, child, or any other animal relentlessly and never stop until it dies, 100 percent of the time. That’s our goal, okay? Now, let’s make the crazy assumption that we achieve that goal, and we produce, I don’t know, fifty dogs, a hundred dogs, even a thousand dogs that all have the same amount of this supernatural trait. For our purposes, we’ll call them ‘Crazy Dogs.’”
As he previously pointed out, “The moment our dog mates with any other type of dog, half of that genetic material is lost, so now you have a litter that’s only 50 percent Crazy Dog. If that litter reproduces, then their offspring are only 25 percent Crazy Dog. Then it goes down to 12.5 percent, 6.25 percent, et cetera. Within only seven generations, you’re at 1 percent Crazy Dog, and that’s assuming you were 100 percent successful at the beginning, which we know isn’t true of any breeder or any type of dog. Especially when you’re talking about complex behaviors like fighting, it just doesn’t work that way. There are probably constellations of genes, maybe even hundreds or thousands of genes that are contributing to that behavior. You have to get the right neuron shape, the appropriate amount of neurotransmitters, all these things.
“So,” he continued, “the idea that any dog that has an ancestor—however many generations back—that had a head shape that cast a shadow against a wall that looked like the shape of a dog that bit someone in the pants . . . the idea that this dog is now going to be biting people is absolutely ludicrous! Americans watch too many zombie movies.”
A number of other studies have confirmed that dogs lash out most frequently from fear and anxiety, not “rage.” Not every dog that displays these behaviors has been abused, neglected, or formally trained, but overwhelmingly, the factors most highly correlated with dog aggression, such as the dog’s early development, its level of socialization with people and other dogs, how it is contained, and which training methods the owner uses, are completely within the owner’s control. Research indicates that these factors are far more important than the physical shape of the dog in determining its behavior.
Our own perceptions and expectations of the animals we encounter play a role in this, as well. “Dog breeds develop reputations,” writes the biologist Ray Coppinger, “and those reputations color people’s interactions with them.”
The fearful responses of people to a perceived aggressive breed “teaches” the shepherds or pit bulls to be aggressive with people. As the dog walks the streets, some people, almost imperceptibly, will take a step back or away from the dog. In two weeks the dog can become aggressive toward people. If people treated a golden retriever the same way, in theory one would get the same results.
Are shepherds genetically aggressive? Yes! Where are the genes for aggression? In their coat color and shape. It is a feedback system, where each time a person steps back from the shepherd because of its coloring and shape, the dog becomes more responsive to the move, and the people react more demonstratively to its movement, and so on. Can you train the dog not to be aggressive once it has learned to be? Probably not satisfactorily.
Okay, then can you breed people-aggressiveness out of shepherds? Of course! I’d start by breeding shepherds to have yellow coats and floppy ears. “Gameness,” however one defines that elusive quality, has never been studied in the laboratory with other variables held constant. Nor is it defined with any consistency. That’s not to say it doesn’t exist—there’s much anecdotal evidence that it does—but we have no way of measuring it. And, as we know, not all pit bulls come from fighting stock, anyway. The Stafford and AmStaff are show breeds, as is the American bully. Most APBTs come from conformation/ pet lines as well. So, the selective pressure for “gameness” was relaxed for most pit bulls between 80 and 150 years ago. As a result, many have retained their looks but not their historical working drives.
If we want to own dogs, their teeth come along. It is up to us to learn how and when dogs use them and to keep our dogs out of situations where they feel they need to. Aside from that, we must also accept that sometimes accidents and misunderstandings, even tragedies, can happen. As much as we may want them, there are no simple answers.
Excerpted from Pit Bull by Bronwen Dickey. Copyright © 2016 by Random House. Excerpted by permission of Alfred A. Knopf, a division of Random House LLC. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
Wellness: Healthy Living
Arizona genetics researchers are taking the unusual step of asking for dog lovers’ help in fighting a mysterious, potentially lethal infection that plagues both dog and man.
They are looking for dogs to be registered and potentially to have their DNA collected to help combat valley fever, a fungus-based disease once confined to the Southwest desert but is now spreading across the country.
Valley fever can be triggered by inhalation of just a handful of spores of a particular fungus. People, dogs and cats are susceptible to the illness that was once believed to occur only in Arizona and California. The disease is not contagious and is not spread from species to species.
The risk for valley fever increases as climates get drier, say California State University, Bakersfield researchers. Warmer temperatures and less rain basically kill off the fungus’ competitors for nutrients and thereby creating an ideal growing environment for the infection-causing fungus.
Valley fever is now being reported in states such as Michigan, Ohio and Minnesota, which never used to see the condition. And the states that typically see the condition are reporting more and more cases: The number of Valley Fever reports is increasing in more than a third of California’s counties, putting more dogs at risk for a disease that can lead to lameness, extreme weight loss and coma.
When Charlie, a 75-pound Chocolate Lab, started coughing, it didn’t set off any alarms. But then he developed a fever and was diagnosed as having kennel cough, which can be easily treated by antibiotics and steroids. Then the symptoms returned and again it was misdiagnosed as pneumonia. More than two months passed before Charlie was given the correct medication; the delay in a correct diagnosis lessens his chances for a full recovery.
Charlie now spends most of his time sleeping off the effects of valley fever, instead of being his normal playful self.
There is no cure for valley fever. Currently treatments focus on helping dogs beat the symptoms. Vet bills can mount up since a dog may have to get medication for up to eighteen months; in some severe cases, a dog may be on medicine for the rest of his life. It is estimated that Arizona dog lovers spend $60 million per year in caring for dogs with valley fever.
Seeing the increase in valley fever cases across the U.S., Phoenix-based Translational Genomics Research Institute (TGen) researchers are now asking for dog people to take a brief online survey about their pet’s breed, health history and lifestyle. After the survey, the dog may be selected to give a saliva sample.
Then after the swabbing is done, researchers will look for differences in the genes of dogs who are sick compared to dogs who show signs of exposure to valley fever but who aren’t sick.
“In certain dogs, a minor infection can progress to severe disease, and the reasons for this are unknown,” said Dr. Bridget Barker, assistant professor and head of TGen’s Northern Arizona Center for Valley Fever Research in Flagstaff, Ariz.
This information would be used to help develop new therapies for both dogs and people, she said.
For more information about TGen’s Valley Fever PAWS (Prevention, Awareness, Working for Solutions), visit us on Facebook at www.facebook.com/vfpaws, and on Twitter at @ValleyFeverPAWS.
Wellness: Health Care
On the trail of canine cancer
In Dog Diseases Treated by Homeopathy (first published in 1863, before chemotherapy, radiation, biopsies and blood panels), author James Moore advised concerned dog owners on treating cancer: “An operation cannot remove the cancer, but it can remove the tumor, which causes much suffering; the knife is, therefore, merely palliative in its effect. Still, the disease, even then, is likely to return at a period more or less remote.”
Today, the diagnosis isn’t as bleak. Indeed, 50 percent of all canine cancers are curable if caught early enough. Moreover, the disease is mostly an aff liction of old age (tragically, some cancers strike dogs as young as two). It may seem like more dogs get cancer than ever before, but it’s presumably because they enjoy a longer life span, thanks to vaccinations against infectious diseases like parvovirus and distemper, and new treatments for congenital, degenerative and metabolic disorders.
“Cancer” is the broad term for a complex cluster of more than a hundred diseases. Although there are many causes, each type of cancer starts with alterations in genes that tell cells how to function, which triggers accelerated and uncontrolled cell growth. The defective signal may hide in abnormal genes inherited from parents, or germinate when normal genes are exposed to harmful environmental influences.
Some breeds are predisposed to certain types of cancer, and in those cases, a strong inherited genetic component is suspected. It is thought that a small number of genes account for cancer risk, but, although they are directly related to the development of individual cancers, rarely is a single gene the sole cause.
By the time people and dogs pass 70 and 10 years of age, respectively, about 50 percent will have been diagnosed with some type of cancer. The malady accounts for approximately 23 percent of all deaths in people. In dogs, cancer mortality varies across breeds, from under 10 percent to higher than 60 percent.
In general, small dogs weighing less than 20 pounds are at very low risk. (Small dogs have lower levels of IGF-1, a hormone that is related to bone and tissue growth. Researchers suspect this may be one reason they have a lower incidence of cancer.) For instance, the chance that a Chihuahua, Dachshund, Maltese, Miniature Pinscher or Pomeranian will get cancer is less than 10 percent. Breeds with the highest risk include the Bernese Mountain Dog, Bouvier des Flandres, Boxer, Bullmastiff and Golden Retriever (Fleming et al. 2011).
Goldens as Case Studies
Interestingly, cancer risk in Europeanbred Goldens appears to be significantly lower. A 2010 study put the mortality figure at 38.8 percent (Dobson 2012, Adams et al. 2010). Although much higher than average, the incidence is substantially lower than that found in North American Goldens.
Goldens in Europe and the U.S. may look similar, but there are enough DNA differences to separate the dogs into two distinct populations corresponding to their geographic regions. Gene pools on both continents are large, so breeding between the two populations is rare.
When studied in the lab, genomic differences suggest that risk for some types of cancer is related to recent genetic mutations in North American Golden Retrievers. And this could be good news: genetic differences between European and North American Golden Retrievers may be key to understanding the etiology of canine cancer overall.
Population, Popularity and Popular Sires
Registration agencies impose strict standards on pedigreed dogs, requiring that the ancestors of each dog be registered as well. This, combined with widespread use of popular sires, means that each breed is a closed population, with no gene flow. The “popular-sire” effect occurs when an animal with desirable attributes is bred repeatedly. Descendants share specific genetic mutations, both good and bad, and those mutations spread rapidly throughout the gene pool, where they may become permanently established, or fixed. (“Fixation” is a change in a gene pool in which at least two variants of a particular gene are reduced to only one.)
When the 1998 GRCA study confirmed that a high number of Goldens were dying of cancer, club members realized they had both a problem and an opportunity. The club’s nonprofit 501(c)(3) fundraising offshoot, the Golden Retriever Foundation (GRF), got off the ground about the same time the survey results were being analyzed.
It started by funding a few cancer studies, including some managed by Morris Animal Foundation (MAF), a nonprofit that invests in science to advance animal health worldwide. Eventually, GRF contributed $1 million and asked MAF to match it if both could agree on a project.
In the meantime, at a MAF canine cancer summit in Chicago, three goals were promulgated: build a tumor archive, fund more canine cancer studies and devise prevention strategies. In response to this collaborative effort, a team of scientists, epidemiologists, veterinary oncologists and surgeons, nutritionists, toxicologists, geneticists, breeders, and donors spent three-anda- half years designing the ideal study. Not an easy task.
Animal epidemiology studies (which deal with the incidence, distribution and possible control of diseases) are few in number, largely because they face so many obstacles. Among them are limited funding, participating private practices using non-standardized methods to record data, pedigrees that are difficult to confirm, and grieving owners who aren’t eager to authorize post-mortem tests. Some cancers are silent killers, so a sudden death may not be attributed to cancer. And, due to attrition, studies are difficult to adequately enroll and don’t last long enough to develop statistically significant patterns.
However, after almost four years of stops and starts, the Morris Animal Foundation Golden Retriever Lifetime Study, the first breed-specific, life-todeath research project of its kind, was launched on August 30, 2012.
Based on observations summarized in questionnaires, researchers hope to identify potentially modifiable risk factors that may account for the high incidence of cancer and other diseases in Golden Retrievers and, eventually, in all dogs. Funded and managed by MAF, the study will investigate the effects of genetics, nutrition and exposure to environmental factors.
Although other breeds are at higher risk for cancer, Golden Retrievers were chosen because their population exceeds that of most other breeds by a large margin: the larger the sample size, the more accurate the data. Additionally, because these versatile dogs perform multiple jobs—from assistance and search-and-rescue work to field, performance and companion tasks—they are subject to a broad range of environmental exposures.
Rodney Page, veterinary oncologist and director of Colorado State University’s Flint Animal Cancer Center and the project’s principal investigator, describes some of the factors underlying the study. “Within the estimates that we currently have, we know that 50 percent of canine cancers are curable with surgery and other treatments. Our study is addressing the ones you can’t cut out: the 15 percent of mast cell tumors that aren’t operable; lymphoma, a whole-body cancer; osteosarcoma and hemangiosarcoma, because they spread rapidly before they’re discovered. These four types of cancer cause approximately 80 percent of cancer deaths in Golden Retriever dogs.” These fatal cancers begin to increase in incidence around five to six years and peak about age nine or ten. However, they may also develop in dogs age two and younger.
More than 2,050 veterinarians are providing health care for enrolled dogs. Annually, they conduct physical exams and report findings online; collect samples of blood, urine, feces, hair and toenail clippings and send them to participating laboratories; submit health information from additional heath visits; collect tumor tissue samples when applicable; and provide owners with information and guidance to help them make a choice about necropsy (an autopsy performed on an animal) after the dog dies.
Participating veterinarian Stephanie Ensley of Bentonville, Ark., who enrolled her own Golden in the program, elaborated on the study’s intent. “The information we’ll gather looks at areas of potential exposure by air, contact and feeding. Owners are expected to provide information as detailed as chemicals used in the home, yard and on the dog, and drinking water sources, to name just a few. When all this information is put together and analyzed, we’ll have an opportunity to find commonalities that may be related to cancer and other diseases. The more data available, the more opportunity to find a connection. On the flip side, we’ll also find commonalities in dogs who live to be 15 and over.”
Among the study’s other expected outcomes are insights into how dog-breeding practices and lifestyle choices might be modified to reduce the prevalence of myriad diseases, and the creation of a repository of biological samples that may be made available to researchers working to develop genetic tests.
As GRCA research facilitator and breeder Rhonda Hovan, who has been a Golden Retriever advocate for 45 years, notes, “Breeders play a special role in the success of the study because they can recruit multiple siblings who share the same genetic heritage. Data from littermates who experience different environmental factors and diets during their lifetimes may provide unique scientific insights that could make a significant impact on the long-term health of dogs.”
One immediate benefit is that veterinarians, dog owners and dogs won’t have to wait until the study is complete to see results that may help influence and improve veterinary medicine. The questionnaire responses are analyzed quarterly, so information is continually streaming into the study, and trends, once validated, will be published as they emerge.
Genetic testing to eliminate dogs from the breeding pool may not be the panacea it first appears. Dogs share more the 300 inherited diseases with humans, from narcolepsy and hemophilia to diabetes and lupus. It’s unlikely that all of these can be bred away from while still maintaining healthy genetic diversity. Reducing diversity increases risk for other diseases to surface in the future, especially in a breed like the Golden Retriever, one that has already experienced diversity loss caused by widespread use of popular sires.
In an article published in Golden Retriever News (Nov/Dec 2014), Hovan cautioned Golden Retriever breeders: “Keep in mind that when we remove a dog from breeding due to a failed health test or for any other reason, we are removing all of that dog’s genes from the gene pool, not just the genes associated with disease or unwanted traits …” She also observed that rigorously removing dogs affected with minor conditions has far more potential to damage future generations than occasionally and carefully breeding them. Breeding away from targeted conditions, she says, is part of an inescapable loop that presents subsequent generations with an elevated risk of having some other problem arise. “When conditions are targeted without good cause, there’s an all-too-real possibility that the ‘something else’ will be worse than whatever it is we tried to breed away from to begin with.”
Eliminating dogs based on genetic tests is not a sustainable way to control disease. A better approach, Hovan explained, is to “test and replace” as opposed to “test and eliminate.” For diseases with a recessive mode of inheritance, breeders can avoid risk by breeding carrier and affected dogs to normal dogs. That way, the genetic variety represented by the line can be maintained for as many generations as it takes to arrive at genetically normal offspring.
As Hovan went on to say, “To make good decisions as caretakers of our breed, we need to know what we’re working with. You can’t change what you don’t measure.” To this end, GRCA is working with a research team from University of California, Davis, to survey the breed’s genetic diversity across types and geographic location, collecting samples from the U.S. and Canada. Referencing this survey, Hovan added, “We want to approach this in a scientific manner. This study will help to clarify what we need to do and provide a road map so we can move forward.”
Could one solution be as straightforward as avoiding environmental triggers that trip biological switches and activate uncontrolled cell growth? Maybe. Researchers expect to collect enough biological samples to accurately define the incidence of each cancer being studied. When the study ends, researchers will also have a detailed life story of every enrolled dog. The hope is that in the long run, data will show relationships between cancers and exposures.
The population-based study is creating a baseline for future research in all sorts of health-related issues. According to Page, “The samples and data we are collecting now will be used by scientists in the future to answer their own questions about health and wellness issues in dogs. Studies will be encouraged that access these assets for analyses of everything from toxic exposures to microbial populations in the gut as they might influence health outcomes.”
Cohort studies like the Golden Retriever Lifetime Study are costly, susceptible to attrition and take a long time to produce statistically useful information. Their value depends on an organization’s capacity to stay in touch and engage all participants. DVM, PhD and CEO of Morris Animal Foundation David Haworth, who also enrolled his dog in the program, summarizes it most concisely: “A study like this can only happen through the active participation of an extended community of dog owners, dogs, veterinarians and study sponsors. I think I can say with absolute certainty that we have one of the most active groups of study subjects of any longitudinal health study ever initiated. After all, they are Golden Retrievers.”
Recently we reported on the use of genetic testing of dogs in a Manhattan luxury co-op.That time it was used to ferret out the breeds that a co-op board thought unsuitable for its residents, including Basset Hound, St. Bernard, and even Shih Tzu. It even went so far as requiring such testing to detail the percentage of each breed in any mixed dog—a ridiculous expectation because of the unreliability for such current DNA testing.
But now there is another story from New York, or in this case, Brooklyn, that actually focuses attention on the misadventures of the dog guardians themselves. While this story involves DNA testing too, it isn’t to finger breeds, but to identify which dogs were allowed to defecate (and do other messy things) inside of the One Brooklyn Bridge Park condo complex. This condo is one of those few dog friendly ones, even boosting a Wag Club (grooming and training center) on its ground flour. It has 440 units, and it's estimated to also be home to 175 dogs. But, get this, some people have been allowing their dogs to relieve themselves inside the building, on staircases, along hallways and even in elevators! Incredible, isn’t it? Even bad weather can’t justify such discourtesy and lack of common decorum. As was noted in the article:
“During December, the memo revealed, there were 52 reported occurrences, ‘a mix of diarrhea, feces, urine and vomit: found on virtually every floor including the main lobby and north and south lobbies; found in all five elevators and with the staff cleanup time ranging from 10 to 50 minutes (average time roughly 20 minutes) per incident.’”
So the decision was made to have all resident dogs have their DNA registered and kept on file to help to find who was fouling the common area. Do note that this building, where a two-bedroom goes for $2.5 million, is welcoming to dogs, its board president has a Shih Tzu-Poodle mix (that wouldn’t be allowed in that Manhattan co-op), so they clearly understand that mistakes can happen. As was reported:
In fact, the building had maintained a very tolerant position toward dogs that couldn’t make it to the ground floor. If your dog had an accident, you took care of it as best you could and then told the concierge, who alerted a porter to clean up the remains.
But certainly enough is enough, so it was decided that more needed to be done. The board went ahead and employed a service called Poo Prints, a subsidiary of a biotech company in Tennessee, which has attracted over 1,000 apartment and condominium buildings around the country to its service. So for the low cost of $35 for such each test and registration—balance that out by the cost of an unit in that building—everyone can hope the soiling will stop and the true culprits are caught. Even though this measure might have an element of shaming in it, it does seem to have helped. Since May when the program started, seven matches were made with fines of $250. And one resident was even caught twice.
What do you think? Any other suggestions of how to get people to act responsibly when it comes to picking up after their dogs? And while allowing your dog to poop inside a building and expecting others to clean up for you seems to be outlandish, there are still those who seem to refuse to pick up after their pups in parks, along trails and sidewalks too. This is the number one problem that communities still have about our dogs, and sadly, it reflects badly on all of us. So would love to come up with creative solutions, do you have any that have worked in your area?
Dog's Life: Lifestyle
Dog fur brings back grooming memories
Having dog fur on the brain is common for me. In fact, it’s my normal state, like dog fur on my clothes, and highly preferable to dog fur on my tongue. (I love dogs, but I hate it when they shed and it ends up in my mouth. Ugh! Not only does it feel weird, but it interferes with my ability to enjoy chocolate and that is simply not okay.)
Because I worked as a dog groomer for a year, I feel nearly as familiar with dog coats as I do with dog behavior, which is my real specialty. So, when I saw an online quiz titled “Can You Tell The Dog By Its Fur,” I had to take it. There are countless quizzes out there and I usually avoid them because of the time sink that they are, but this one was irresistible. There was self-imposed pressure not to miss any, and I’m happy to report that my grooming time was not in vain—I knew all 12 coats well enough to answer correctly. I suspect many dog people will have similar success.
Of course, not everyone will think of the coats the same way I do, but I hope my fellow groomers will.
When I see dogs, I am often impressed with the beauty of their coats. That may simply reflect my personal experience with how much work it can take to keep them looking that way. Or, it may just be that I know fur and I love it.
Culture: Science & History
Breeders, judges and historians talk about breed standards—why they work and when they don’t
In the world of mammals, the domestic dog— Canis lupus familiaris, a subspecies of the gray wolf— reigns as the most morphologically diverse. Consider, for example, the extremes represented by the 155- pound South Russian Ovcharka and the seven-pound Silky Terrier. This incredible variety can be attributed in part to the dog’s basic template, which can be customized by the manipulation of a very small number of genes.
For instance, 95 percent of all five canine fur textures and lengths (the Afghan Hound and Curly-Coated Retriever curiously excepted) is orchestrated by three genes. Further, just six or seven locations in the canine genome account for nearly 80 percent of dogs’ vast size and weight differences. (In humans, these genes number in the hundreds, if not thousands). A single mutation, shared by 14 diminutive breeds, determines that a dog will be small, and another is responsible for the long-bodied, short-legged nature of numerous dwarf breeds.
Clearly, the dog’s random morphology isn’t quite as arbitrary as we thought, and breeds aren’t quite as unique. Furthermore, canine traits come in packages. Flip a switch to make the legs more slender, and the skull will narrow as well. Turn down the volume on pigment and the chance of deafness increases.
Those who bred dogs had long known that traits were related, but there was little understanding of how those relationships worked; nor was there much concern. Dogs were bred for skills useful in a practical world. Once breed exhibition became a fashionable pastime and working dogs were awarded championships based strictly on appearance, however, all this changed.
In 1866, John Henry Walsh (writing under the pseudonym “Stonehenge”), editor of The Field, the most influential hunting and kennel journal in England, was the first to describe a breed’s physical characteristics with phrases that he believed were equivalent to its field ability. A bird dog judged perfect to a well-written breed standard would, by the logic of the day, perform perfectly in the field.
At the time, horsemen and sportsmen were the dog-fancy glitterati (women became active later), and many of the arcane descriptions in breed standards are borrowed from those arenas. For example, the Poodle’s “straight-forward springy trot” describes the dog’s ability to retrieve and carry a bird. The phrase “stand like a cleverly made hunter” references ideal anatomical construction and proportion in the German Shorthaired Pointer.
Today, breed standards serve three purposes: assessment in competition; delineation of unique qualities in different breeds, some very much alike; and maintenance of breed similarity throughout the world.
The question is, what happens to purebred dogs when language, intrinsically fluid and inexact, is used to suspend change in morphology and behavior? In the late 1990s, as a doctoral student in linguistics at Claremont Graduate University, I conducted a study to find out. Part of the research included interviews with experienced American Kennel Club (AKC) breeders, specialty judges and breed historians. What I heard from them provides some insight into specific ways that a standardized lexicon can influence change in pedigreed dogs far beyond what is intended.
Dogs in Translation For some breeds, international politics played a role. At the first Canine Congress in 1886, the Germans were opposed to the Swiss-type Saint Bernard, favoring the bulkier English type. Nothing was resolved until 1887, when the Swiss dog was finally approved as the international type. The United States club, with its strong ties to England, adopted the international standard in words, but in practice, bred to the English type.
During an interview, as three Saints gnawed on bones nearby, an experienced breeder and specialty judge offered his opinion: “This changed the morphology of the American Saint, most noticeably in the head. The Saint Bernard standard was translated, with some errors, from German to English in 1888. For instance, ‘when in action’ should have read ‘when excited or alert.’ The phrase, ‘the horizontal axis of the head’ should have read ‘the long axis of the head.’” More than a century later, the club had still not made corrections, perhaps because, as linguists argue, translation of a lexicon from one language to another can never be exact.
Translations are more like corrections or clarifications. When standards are clarified, they usually get longer and, consequently, more exclusive. A standard that calls for feet to be “round, compact, catlike, standing well upon the toe pads,” is more restrictive than one that says feet must be “close, round and firm.” Revisionists tread cautiously because an imprecisely rephrased standard can have an impact on a breed’s genetic diversity.
Amending a standard for any reason is controversial for those entrenched in a time-honored tradition devoted to blueblood history (albeit a fanciful history, since geneticists tell us that very few breeds are as old as they were once touted). As one Greyhound breeder observed, “The torch handed to us was the perfect coursing dog. Our standard is taken word for word from what Stonehenge wrote in the 1860s. If we added more words to make it more explicit, it may end up being a Greyhound different than the one each one of us has in our head.”
But progress necessitates change. A handful of words differentiate an apple, an orange or a pear, but 13 varieties of apples require a larger lexicon. In his 1576 treatise, Of Englishe Dogges: The Diversities, the Names, the Natures, and the Properties, cynologist John Caius described the generic land Spaniel in 58 words: “The most part of their skins are white and if they be marked with any spots, they are commonly red, and somewhat great therewithal, the hairs not growing in such thickness but that the mixture of them may easily be perceived. Other some of them be reddish and blackish, but of that sort there be but a few.” Today, Caius’s dog has morphed into 13 f lushing Spaniel breeds. The Field Spaniel standard uses 973 words, short in comparison to the English Springer Spaniel standard, a 2,040 word descriptor.
Occasionally, words are added to explain what something is not. As one breed standard committee member noted, “There were lots of questions from judges about the preferred shape of the eye opening. So we said it’s acceptable as long as it’s not this, that or the other thing.” And at a California dog show, pointing to Mastiffs benched only a few feet from his St. Bernards, an exhibitor told me, “Sometimes breed clubs have to lengthen standards to differentiate their breeds from others so similar that, if marked differently, could be shown as Saints.”
When Words Fail Dressed in formal attire appropriate for the straitlaced Madison Avenue cocktail party that precedes every Westminster dog show, AKC VIPs sipped their drinks and talked candidly about breed standards.
A Doberman breeder, specialty and all-breed judge opined, “I’m not sure that the standard hasn’t been what’s wrong with some of the breeds, in that by naming and describing the criteria with which the animal is to be judged, the words lack exactness. When people bred to the standard, the animal changed and became what the words described. Also, some groups wrote the standard and have not been able to breed to that ideal, so now, they change the nuance of the words to fit the breed ideal. Making the dogs fit the words, and not vice-versa, is wrong.”
For instance, a standard that establishes criteria to develop the best muzzle shouldn’t include terms that are subjective or indefinite. Or as one judge said, “If the standard calls for a short muzzle, judges select dogs based on the shortest muzzles in the ring. The breed’s muzzle gets shorter and shorter. So you have to ask, ‘Shorter than what?’”
Another said, “Our standard calls for the ear, when pulled forward, to reach the eye. You see so many dogs in the ring now with longer ears. We always say, well, which eye is it supposed to reach, and is it pulled under the muzzle or over it? I have never seen a Golden Retriever with ears too short.”
Some breeders get so fixated on one attribute of the traditional standard that they are willing to sacrifice something more important. “For example, they may create a broad head but are willing to accept shorter legs and a longer back in order to do so,” another judge observed.
Breed standards, like all nomenclature, are subject to the rules of language. Like the dog it describes, vocabulary is deceptively capricious and unexpectedly fluid. A good example is size. Big breeds are getting bigger. As I was told by a breed historian in reference to St. Bernards, “What was bred to be powerful and strong in 1900 would not be considered powerful and strong today. Like an automobile in 1915, it was powerful then but not compared to now.” If a standard describes a breed as strong and powerful, the ideal dog gets bigger.
Rather than hack away at standards, some breed clubs hold seminars for judges in which contemporary nuances of an indefinite vocabulary are refined. Others reluctantly reword phrases to accommodate inexperienced newcomers (currently, the average length of interest and activity in the dog fancy is five years or less). A Golden Retriever breeder told me, “People who wrote the original standard were horse people, and this is where the phrase, ‘deep through the heart’ came from. It had two meanings, deep through the chest and courageous. The original meaning and nuance of the old words is often lost on today’s breeders, or is interpreted to mean something else.” After years of debate, the phrase was reluctantly changed to “deep through the chest.” Some clubs don’t revise words, but instead, reinterpret their meanings. Take English Bulldogs, for example. As an owner of one of these stocky dogs remarked, “The interpretation of words has changed. The Victorian [Bull]dog was a transition dog, less bulky, less massive, taller, leaner, and is now thicker and more compact.” Another handler observed that “one of the issues in the standard is weight. It calls for 45 to 50 pounds. But it has no height restriction, so a higher-station dog might be thinner.” The 1910 dog was a much taller and leaner dog compared to today’s stout fireplug variety, but both are considered to have been bred correctly to the standard.
A German Shepherd breeder and specialty judge who chairs the club’s standard committee told me that “you can have the same words in several standards, but they don’t mean the same thing. We use the word ‘almondshaped’ in our standard. But if you look at other breed standards, both the Collie and American Cocker call for almond-shaped eyes. The Collie has a small triangular eye and the Cocker’s is a goggle-eye [the eye protrudes from the skull].”
Judges Play a Role A specialty judge is an experienced breeder and expert on a particular breed. An all-breed judge is a generalist qualified to judge several breeds. The specialty judge brings meaning to the words in the standard, and the allbreed judge makes sure the words mean what they say.
A specialty judge who also works as an all-breed judge explained that the interpretation of complex descriptions, such as the angle of the hock, is more difficult for a generalist all-breed judge to measure. “Because it’s easier to see a proper bite than a proper angulation, the bite may be given more significance than something more important, such as angulation of the hindquarters.” On the other hand, the all-breed judge tests the words. “If the breed club thinks the all-breed judge is misinterpreting the standard, then they need to rewrite it. The judge shouldn’t choose the dog that he thinks they mean.”
War of Words The AKC considers itself a club of clubs. Owners intent on breed registration must first demonstrate that a majority of breeders are interested in establishing a national breed club. Who gets to be in that club is at the heart of a mounting number of controversies.
In 1994, the AKC Labrador Retriever standard was revised to exclude dogs less than 22 inches at the withers (or 21 inches for bitches). Some breeders whose dogs no longer met the standard were part of an $11 million class-action suit against the AKC Labrador Retriever Parent Club (the national organization designated by AKC to represent the breed), claiming that height restrictions excluding shorter dogs no longer described the Labrador Retriever: if you make a bigger dog, you make a different dog. A litigant told me, “It’s perfectly reasonable to change a breed, but the dog should have a different name.” They tried and failed to trademark the name Labrador Retriever; the judge sided with the AKC parent club. The Border Collie war began in 1988, when the American Border Collie Association and others heard rumblings that some wanted to register the breed for conformation showing, which requires a breed standard. This idea didn’t go over well with herding trial enthusiasts; a Border Collie is what it does, not what it looks like. Any dog can enter an open sheepdog trial. There are no age, size, color, shape or breed restrictions, and registration is not required. Unlike registered purebreds, whose lineage must be proven in ancient studbooks, many Border Collie champions are registered on merit (ROM). In theory, a Pomeranian who could prove its worth at a sheepdog trial could, by performance, be called a Border Collie.
In the minds of many, AKC conformation specifications threatened 200 years of breeding for performance, not looks. Led by Donald McCaig, who retold the tale in his book The Dog Wars (2007, Outrun Press), the group prepared for battle: “Hands off the Border Collie! We own Border Collies. Our dogs are companion dogs, obedience dogs and livestock-herding dogs. For hundreds of years, Border Collies have been bred to strict performance standards and today they’re the soundest, most trainable dogs in the world. The AKC wants to push them out of the Miscellaneous Class and into the show ring. They seek a conformation standard [appearance standard] for the breed. We, the officers of every single legitimate national, regional and state Border Collie association, reject conformation breeding. Too often, the show ring fattens the puppy mills and creates unsound dogs. We will not permit the AKC to ruin our dogs.”
They filed to legally trademark the name but, like the Lab litigants, lost in court. In 1997, the first Border Collie was shown in conformation at Westminster. I was there that year and interviewed a handler/owner who had been instrumental in getting the breed registered and in writing the standard. I asked her how she did her research. “This dog is shown in Australia, the British Isles and New Zealand. So I read their standards and asked them what they would do differently if they could. I tried to emphasize movement and gait. The standard shouldn’t describe a still dog. The Border Collie is almost a vision of movement even when it is standing still … always poised on the brink of action. The head drops for a reason. It is common knowledge among Border Collie people. That’s why I didn’t include a description of the head in the standard. I thought everybody would know that.”
In the benching area, surrounded by panting dogs crowded into crates and standing patiently while being primped on grooming tables, the woman sat in a folding chair, visibly distraught. Tearyeyed, she continued: “Right before you got here, a prominent breeder came by and said he will breed a dog with the head held higher. The head has to do with movement in the field, in making eye contact with the sheep, the pattern of behavior that has evolved from two centuries of work. Now I regret having fought so hard for this. The standard should not threaten the dog as a working animal, but I believe it now will.” About the same time the Border Collie war was raging, AKC enthusiasts saw an opportunity to register the Jack Russell Terrier (JRT), an irascible, independent dog with an intense work ethic, extremely diverse genome and phenotype as dissimilar as that of the Border Collie. Many Jack Russell Terrier breeders vehemently opposed the action, claiming that the breed’s physical and working characteristics would be jeopardized by this move. Nevertheless, the splinter group formed the requisite national breed club, named itself the Jack Russell Terrier Breeders Association (JRTBA) and gained AKC recognition in 2001.
A lawsuit ensued. After an expensive court battle, the name Jack Russell Terrier was awarded to the working phenotype and the AKC changed the conformation dog’s name to Parson Russell Terrier. The AKC parent club is now the Parson Russell Terrier Association of America.
Writer Alston Chase, who includes the story of the breakup of the breed in his book We Give Our Hearts to Dogs to Tear (2008, Transaction Publishers), told me, “The Jack Russell Terrier is a feisty, very aggressive, very tough dog. But middle-class urbanites don’t really want that kind of dog. They want a dog that will be a good pet.” Chase, who lives in rural Montana, has bred the working terrier since the 1970s.
The public took notice of the rather obscure breed when it became a media darling in the 1980s. Chase said, “The overbreeding followed the popularity driven by the media, not by the dog itself.” Aggressive and difficult in a pet environment, the breed was misrepresented as a mischievous lap dog on shows like the NBC sitcom Frasier. Surprised and disappointed by their dogs’ ornery personalities and exercise requirements, urban pet owners abandoned JRTs at shelters in record numbers.
According to Chase, one of only a handful of people in the U.S. continuing to breed the old-fashioned dog, “We’re doing what we can to prevent extinction of the original breed, but people aren’t in love with the value of diversity in the dog. They want dogs that look alike.”
Geneticist Jasper Rine, in a letter to the AKC supporting the Border Collie anti-conformation campaign (included in the appendix of McCaig’s 2007 book), predicted what was to come. “It may be nearly impossible to breed for a particular behavior based on heterozygous advantage and still achieve a homogenous conformation.” Breeding dogs for fixed conformation means breeding for homozygosis (the formation of genetically identical gametes) of the genes that contribute to appearance. In doing so, genetic linkage (the tendency of genes located in proximity to each other on a chromosome to be inherited together during meiosis, or cell division) may result in genes near those controlling conformation becoming homozygous as well. Unfortunately, chance determines which genes are swept up. By breeding for conformation, breeders may be breeding away from desirable behavior, even putting alleles (forms of a gene) at risk for extinction.
So, what has happened to the Labrador Retriever, Border Collie and Jack Russell Terrier over the last 15 years?
The shorter-legged, more compact field-bred Lab continues to be shown in Canada, the UK and other countries that don’t disqualify individuals based on size. In the U.S., conformation and companion Labs are getting increasingly larger. Will diseases linked to large size compromise the American line? Time will tell.
As a consequence of the acrimonious Border Collie war, few working dog breeders had a desire to become specialty judges, so the fate of the conformation dog was left in the hands of generalist judges who lacked sheepdogtrial experience. As predicted, the standard created a split type: working dogs continue to be a rag-tag group, dissimilar in shape, size and color, but the same in their relentless determination to move sheep from one place to another. In contrast, AKC dogs look very similar, but their ability to herd sheep is open to question. Are both types called Border Collies? Formally, yes, but the AKC dog is widely, popularly and even affectionately known as the “Barbie Collie” by some: pretty as a picture, but, according to the member-owned American Border Collie Association and others, as blandly attractive and vacuous as the doll from which the name derives.
The working Border Collie is safe for now, but the old-fashioned Jack Russell Terrier can hardly be found. Like the Old English Bulldog who faded away with the passage of the 1835 Cruelty to Animals Act and the Wolfhound who died out with the demise of the wolf in the British Isles, the pre-AKC JRT will likely disappear as well. Eventually, sentimental breeders may attempt to recreate the breed when they realize what they’ve lost, and they may perhaps have some success in replicating the way the dog appeared. But the breed’s signature obstreperous temperament is something people will only read about in books.
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It would seem, then, that words are indeed powerful. To say that the lexicon used to describe a purebred dog, or even name one, will not affect the way we engineer the animal contradicts the language-relativity hypothesis, which holds that the vernacular we use to frame our perceptions influences the way we regard, understand, interpret and reinvent them. As a tool, language plays an important role by which innovation—in this case, of a sentient human-made domestic animal—is further developed. Or, as the AKC says, refined.
To paraphrase Shakespeare, would a rose by any other name smell as sweet? If you’re talking about dog breeds, that’s not a rhetorical question. The answer is no.
Good Dog: Studies & Research
The Beauty of Diversity
For those of us who love dogs, using DNA tests to deconstruct our mongrel pooch’s mysterious heritage is appealing because we want to be able to answer the question, “What kind of dog is that?” Companies say that DNA-based diagnostic tests, which sell for about $60, can answer the question by comparing your dog’s DNA to over 100 of the most popular breeds. But are the tests accurate? I decided to find out.
Chance, a 10-year-old mixed-breed dog who has lived with me for six years, was my guinea pig. I tested his DNA using three different tests. In 2008, when I wrote the prequel to this article (read it online at thebark.com/dna), I had his ancestry tested with the Canine Heritage Breed Test. At that time, the company used 96 markers and tracked them to 38 breeds. A marker is a gene or DNA sequence on a chromosome that indicates “breedness.” The labs claim that the markers they use are 99 percent accurate.
In May 2012, when I began doing research for this follow-up article, I tested his DNA with the amplified Canine Heritage Breed Test again because it had been substantially improved to 400 markers and 120 popular breeds. I could have paid $25 to upgrade the 2008 test. But to be fair in my test-of-the-tests experiment, I submitted his cheek swab under a different name and without a photograph, just in case, as many people believe, the tests are a scam. In addition, I used the MARS Wisdom Panel Mixed Breed Identification Test. Mars looks at 321 markers and includes 185 breeds in its database.*
To analyze and compare the results fairly, I needed to find out if the tests were processed the same way, and I researched the history of the breeds identified in Chance’s ancestry.
Comparing the Tests
If a primary parent breed can’t be identified in the DNA, the program will look for a secondary grandparent breed, and so on and so forth, until it eventually clusters with a distant breed (if there is one). If there are no purebred ancestors, remnant breeds will be sought.
To identify markers that characterize a breed, labs take samples from multiple thousands of individual dogs representative of more than a hundred breeds. However, those dogs differ from one laboratory to the next. Although their sample sizes are big enough to absorb minor differences, no two dogs are exactly alike. Plus, line-bred dogs can affect results. For example, Labrador Retrievers bred exclusively for hunting may be more like each other than they are like the breed.
Finally, descriptive terminology differs. Canine Heritage uses primary, secondary and in the mix. Wisdom Panel uses parent, grandparent, great-grandparent and next best breed matches that include percentiles.
Because Chance has no purebred parent, his strongest signal would come from a purebred grandparent. One test indicated a Siberian Husky grandparent. However, the other two tests claimed he has no purebred parent, grandparent or great grandparent. In any case, all three tests concur that a combination of spitz breeds provides the strongest signals in Chance’s ancestry — Siberian Husky, Alaskan Malamute and, to a lesser degree, the Pembroke Welsh Corgi, a breed with some spitz lineage. Although it transmits a faint signal, the Pembroke Welsh Corgi is the only breed that showed up in more than one test. The white German Shepherd and blackand-tan German Shepherd, strong and weak signals respectively, are both named as ancestors and are admixtures of one another. Although they are herding dogs, it’s probable that both breeds have some spitz lineage. The Japanese Chin, a miniature Asian breed derived thousands of years ago from larger mastiff and spitz dogs, is also a fairly strong signal.
Large terriers make up the next strongest signals in his DNA. The German Pinscher, Standard Schnauzer and Doberman Pinscher are closely related. German Pinschers were used to develop the relatively new Doberman Pinscher breed. The Standard Schnauzer, originally called the Wire-haired Pinscher, is directly related to the German Pinscher. Sight hounds are mentioned in two tests. In the late 1800s, Borzois were likely mixed with Huskies to increase speed, and terriers were mixed with Italian Greyhounds.
The weakest signals, in some cases less than 2 percent of his makeup, include a ragtag group of breeds, including Border Collie, English Setter, Cocker Spaniel and Leonberger.
Making Sense of the Findings
The ancestral breeds named in the three tests seem absurdly disparate, but they are not contradictory. They all point to one truth: only a few degrees of separation differentiate Chance from all modern breeds. This is because most purebred dogs have a crippling lack of genetic diversity, which is the unintended consequence of modern breeding practices.
Except for 14 ancient breeds — Afghan, Akita, American Eskimo, Basenji, Canaan Dog, Chinese Shar-Pei, Chow Chow, Dingo, Finnish Spitz, New Guinea Singing Dog, Saluki, Samoyed, Shiba Inu, and Siberian Husky — all our modern breeds were developed in the last few hundred years.1 Although each has its own DNA fingerprint, they have so little genetic diversity that if you go back far enough, the DNA of almost every dog, mixed breed or purebred, will cluster with a few common ancestors. This finding raises the question, “How can breeds that look so different be so closely related.”
The complex DNA of stray mutts on the mean streets of, for instance, Lugazi, Uganda, or Zorzor, Liberia, may answer the question. Ubiquitous freeranging dogs living on the fringes of human settlement are not, as previously believed, semi-feral, mongrelized purebred dogs, but rather, are genetically distinct and subject to the pressures of natural selection. Some populations have been isolated for hundreds, if not thousands, of years. Subsequently the village dog genome remains complex and unabridged.
Suspecting that village dogs may be pure genetic remnants of ancient dogs, Adam Boyko, assistant professor in the Biomedical Sciences Department at the Cornell University College of Veterinary Medicine, co-founded the Village Dog Genetic Diversity Project with his colleague Carlos Bustamante, a genetics professor at Stanford School of Medicine.
The project is a worldwide collaboration of researchers, volunteers and veterinarians who gather canine DNA samples along with photos and information on weight, age, body measurements and coat color. The samples are analyzed at the Canine DNA Bank at the Baker Institute for Animal Health, part of Cornell’s College of Veterinary Medicine, which maintains a growing DNA archive of dogs worldwide.
The scientists believe their work will shed new light on when, where and under what conditions dogs were domesticated, and how dogs have adapted to human settlement, environmental stress and disease.
The first phase of the study included collecting samples from modern breeds, their mixed-breed relatives, breeds reputed to be from remote regions of the world and African village dogs. In 2009, they reported that African village dogs are a mosaic of indigenous dogs descended from more ancient dogs that migrated to Africa.2 Findings also indicated that their genome is being eroded at an alarmingly fast rate as they mate with recently introduced modern dogs. Researchers are now scrambling to find dogs in even more remote locations. In the summer of 2012, workers began collecting DNA samples in Liberia and the Democratic Republic of the Congo.
On a continuum, gray wolves, the progenitor of all dogs, have the most genetic diversity, and purebred dogs have the least. Village dogs’ diversity lies somewhere in between. Because purebred dogs are the result of strong selection for exaggerated traits, they have only a fraction of the genetic diversity displayed by village dogs. The genetic variant that underlies a desirable trait, whether it’s extreme size or intense behavior, has become fixed, wiping away not only competing variants but also variants associated with nearby genes.
Genes located close to each other on a chromosome are said to be linked, and tend to be inherited together or, conversely, wiped away at the same time. Thus, a trait that isn’t selected for can be wiped away simply as a result of being in the wrong place at the wrong time. If that trait happens to affect, for instance, immune response to disease, then that could be a problem.
By comparing the genome of village dogs to that of purebred dogs, scientists hope to be able to identify what’s been lost as a result of intense artificial selection. Dr. Boyko notes that “village dogs offer a chance to understand the mechanisms of certain genetic diseases. Knowing what those genetic variants are might be the first step towards invigorating genetic diversity in some modern breeds.”
The Significance of Canine Origin
Previous studies suggest that dogs originated in places as varied as Eastern Europe, China’s Yangtze River Valley and the Middle East. In a 2002 study, researchers pinpointed East Asia as the place of origin. However, some scientists think these dogs are descendents of an even older population that developed in a different place. Dr. Boyko’s findings confirm this. African village dogs have about the same amount of genetic diversity as those in the East Asian study, suggesting that both groups are the same age. It’s possible that both populations originated together somewhere else and then migrated to East Asia and Africa at about the same time.
To thoroughly complicate matters, the Canidae family does not play by the same rules as most other mammalian families. Unlike, say, horses and donkeys, dogs, wolves, coyotes and golden jackals can interbreed and produce fertile offspring. Consequently, following the genetic trail from domestic dog to wolf leads to a lot of stops and starts and many dead ends as well as plenty of headaches for evolutionary biologists.
A Multi-Disciplinary Approach
As Dr. Larson notes, “There has been so much admixture since dog domestication began, and especially in the last few hundred years, that looking at modern dogs is always going to be problematic. There may be modern populations that are less ‘corrupted’ or admixed, but even they will possess a legacy of several thousand years of crosses with large numbers of populations, and even wolves.” He adds, “The only way forward is to focus on other methods, including, but not limited to, ancient DNA from archaeological dog and wolf remains. And of course, there is the wider interpretation and understanding from lots of other fi elds to put it all in context.”
In the paper, researchers discussed an interesting pattern that emerges when sites with archaeological dog and wolf remains are overlaid onto maps showing the historical distribution of wolves. First, the archaeological remains are not found in the places where ancient breeds are believed to have been developed, intimating that dogs may have been domesticated multiple times from local wolf populations. Second, most of the ancient breeds come from areas where wolves never ranged, suggesting that humans had dogs as they migrated around the globe. Furthermore, dogs only appeared in these locations after agriculture was introduced.
The canine genome’s full story continues to evade scientists, but as DNA technology advances and analysis becomes cheaper and faster, researchers are optimistic that the answers they seek are right around the corner.
Will I continue to test my future shelter rescue mutts to find out who they are, even though I know that the answers will be the same — all modern dogs are so closely related that it’s almost impossible to discriminate ancestry? Probably. Other mysteries lie hidden in our dogs’ DNA. The idea that an animal can be morphed into so many extreme shapes and behaviors yet remain a simple combination of only a few stem parents is one of them.
We like to believe that scientific discovery advances tidily, fact by fact, to prove an irrefutable truth. But science is a messy business. And there is hardly a better example of just how messy than the search to tease out the mysteries hidden in the canine genome.
Photographer Amanda Jones captures the all-American dog
Mixed-breed. Mongrel. Heinz-57. All-American. Mutt. Would a dog by any other name smile as sweet? You may be surprised to know that the most popular, or, shall I say, most prevalent type of dog is now a mixed-breed. There are more mutts in American homes than any single breed—more than Labs, Golden Retrievers and Yorkies (who rank two, three and four, respectively). That’s saying something.
In Amanda Jones’ new book, A Breed Apart: A Celebration of the New American Mutt, she employs her fine artistry to capturing all that we admire about these true one-of-kind dogs. Couture originals each and every one! Let those purists have their papered pups—give me a “breed apart” anytime!
As a lifelong devotee of mutts, I completely understand America’s current fascination. What better candidate could there be for first-place honors in a country that proudly claims to be the world’s melting pot? For going on 10 years now, my job has allowed me to meet wonderful dogs, many of them of “uncertain parentage.” Where do I start to sing their praises?
If every dog has its day, let’s hope that it’s the mutt’s turn now. Even though all dogs originally came from mixed-breed stock eons ago, mutts have played second fiddle to their more high-bred brethren for too long now! The idiosyncratic charms of the dogs in this book speak volumes for the love they share with their humans. With so many exceptional dogs, of all sizes and shapes, awaiting adoptions at local shelters—how can one pass over their uniqueness while also knowing that you saved the life of a dog that was “made” just for you!
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