What Is a Dog?
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What Is a Dog?
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Overview
Of the world’s dogs, fewer than two hundred million are pets, living with humans who provide food, shelter, squeaky toys, and fashionable sweaters. But roaming the planet are four times as many dogs who are their own masters—neighborhood dogs, dump dogs, mountain dogs. They are dogs, not companions, and these dogs, like pigeons or squirrels, are highly adapted scavengers who have evolved to fit particular niches in the vicinity of humans.
This book present an eye-opening analysis of the evolution and adaptations of these unleashed dogs and what they can reveal about the species as a whole. Exploring the natural history of these animals, canine behavior experts Raymond and Lorna Coppingers explain how the village dogs of Vietnam, India, Africa, and Mexico are strikingly similar. These feral dogs, argue the Coppingers, are in fact the truly archetypal dogs, nearly uniform in size and shape and incredibly self-sufficient. Drawing on nearly five decades of research, they show how dogs actually domesticated themselves in order to become such efficient scavengers of human refuse. The Coppingers also examine the behavioral characteristics that enable dogs to live successfully and to reproduce, unconstrained by humans, in environments that we ordinarily do not think of as dog friendly. A fascinating exploration of what it actually means, genetically and behaviorally, to be a dog, What Is a Dog? is likely to change the way beagle or bulldog owners reflect on their four-legged friends.
Product Details
| ISBN-13: | 9780226359007 |
|---|---|
| Publisher: | University of Chicago Press |
| Publication date: | 03/04/2020 |
| Sold by: | Barnes & Noble |
| Format: | eBook |
| Pages: | 257 |
| Sales rank: | 78,237 |
| File size: | 5 MB |
About the Author
Read an Excerpt
What is a Dog?
By Raymond Coppinger, Lorna Coppinger
The University of Chicago Press
Copyright © 2016 The University of ChicagoAll rights reserved.
ISBN: 978-0-226-35900-7
CHAPTER 1
What Is a Dog?
It's a really good question: what is a dog? This question echoes the one asked by our paleontology professor Albert Wood at Amherst College many years ago. His question was "What, if anything, is a rabbit?" Was a rabbit a rodent, descended from the ancestors of species like squirrels and rats? Perhaps it was a hyrax, a little shrew-like animal thought to be related to the elephants, or perhaps the rabbit descended from the ancient marsupials such as ancestors of kangaroos. Somebody thought it was closely related to the primates, which is still a reasonably good hypothesis. The discussion, which started long before Professor Wood's 1957 paper, continues yet. Still nobody quite knows what a rabbit is. All the while, we students knew exactly what a rabbit was when we saw one.
Years later, with two colleagues at Hampshire College, we emulated Professor Wood's classy title and wrote a book chapter called "What, If Anything, Is a Wolf?" The answer to this question is important for wildlife biologists and law-makers who need concrete evidence on which to base decisions about whether an animal is an endangered species — for example, is it a gray wolf, a red wolf, a coyote, or perhaps a hybrid between them — or maybe even a dog? What is a dog?
Currently, there is a suggestion, call it a movement, that the gray wolf (Canis lupus) be removed from the endangered species list because, as the argument goes, its numbers are high and it occupies all its former range. Well, what was its former range? Is the former range measured from the last glacial period, or when the Pilgrims reached America, or from the beginning of the twentieth century when the American government decided to eliminate all wolves from the lower forty-eight states? The sticky question is that government trappers also killed off red wolves and Mexican wolves — and are those different species or even a different subspecies from gray wolves? People argue in court over such designations.
Did the gray wolves ever raise pups in New England and, if so, are they repopulating this former range now? Some argue they never were in New England. How do you know that? Or maybe wolves live in New England now but we have been calling them coyotes by mistake. Some scientists think the New England canid is a wolf — not the gray wolf but a different species of wolf called the Algonquin wolf. At present, the Algonquin wolf is not on the endangered species list because nobody knew they existed as a separate species.
Still other people continue to think the big coyote-like animal living in New England is a cross between a coyote and a dog — a coydog, but others think it is a coywolf. Well, if they are coywolves, as hybrids they are not protected under the Endangered Species Act. Thus our question is still debated among scientists: "What, if anything, is a wolf?" It is important to know, and we still don't.
We grew up with all these different species and thought we knew what they were. Our moms read to us about the big bad wolf in "The Three Little Pigs," and the youngsters watched Wile E. Coyote cartoons on Saturday morning TV. And then there was Lassie and Rin Tin Tin. Dogs are ubiquitous in most of the world. It is hard to imagine anyone on earth not having been exposed to a dog at one time or another. We all know a dog when we see one.
Within the dog family (the Canidae) — coyotes, wolves of all different species and subspecies, jackals of all different species and subspecies, and dingoes, as well as all the species of foxes, dholes, and bush dogs — the dog differs from all the rest of them in many ways, as you will read in this book. Within the genus Canis, wolves, coyotes, jackals, and dingoes are generalized predators. We call them the wild types, to distinguish them from domestic dogs, Canis familiaris, which we call simply "the dog." The wild types look and behave like predators. Scientists study the phylogeny — that is, the evolutionary history — of this closely related genus; they want to know which are more closely related to which, and which evolved first, and when did they evolve, and where and how did the divergence (speciation) between them take place.
With the domestic dog, those questions of when, where, and how they evolved are almost like an obsession for many of us. The dog is different, special, a beautiful animal, and thus we want to know more about the process that produced such an unusual species. How did such an animal evolve so quickly?
Many think C. familiaris is really another form (or subspecies) of the wolf. And maybe it is. But of which wolf species are we thinking? Many who tackle the question are comparing the dog with the large canid creature along the Last Glacial Maximum (about 25,000 years ago) when they look for doglike deviations in the gray wolf skulls. Professor Wood, however, used to waggle his finger at us and say, "If you want to know anything about the evolution of a species don't study their skulls."
When some of us say "wolf," the mental image forms along the lines of "I know a wolf when I see one." And it is big, not a little jackal-sized wolf.
We are in a time when "everybody" claims the dog is a subspecies of the gray wolf. For those of us who are scientists, that is an open question and not an answer. "Method of thinking" is another way of saying that logic, statistics, and science have rules. When one takes a statistics course, one learns the rules of what statistics can do and what it cannot do. A statistician comparing measurements between animals that are labeled "dog" and "wolf" might say the probability that dogs descended from the wolf is p<.001. That means the chance of the relationship being due to chance alone is less than one in a thousand. And most of us would then say that is a fairly high chance that dogs descended from the wolf.
Similarly, the logician might say that:
all wolves have forty-two teeth of a specific arrangement;
that specific number and arrangement are also found in the dog; and,
therefore, dogs and wolves are the same species.
It isn't as silly as it sounds because that is exactly the way the anatomist or systematist thinks. That was the kind of argument that our clever Professor Wood applied to try to find the origins of the rabbit. He counted teeth and looked at the shape of the teeth, and yes, paleontologists looked at the angulation and attachment of the jaw and other organs in the body to get clues as to the origin of the rabbit. Linnaeus counted teeth, which is one reason why he put dogs, wolves, coyotes, jackals, and dingoes in the same genus, Canis.
For both the statistician and the logician, the conclusions aren't necessarily right or wrong. But in each case the method has its limits in what it can tell you.
Science is just the same. Scientists test hypotheses. Dogs and wolves are related, is the hypothesis. Is it true that only wolves and dogs have forty-two teeth? No: jackals and coyotes and dingoes also have forty-two teeth. Then look for other differences between them. They are all, for example, interfertile — maybe they are all the same species. So why do the taxonomists assign them into different species?
The naming of wolves, dogs, coyotes, jackals, and dingoes was all just an unfortunate consequence of history. In 1758, Swedish biologist Carl Linnaeus named the dog Canis familiaris. That was a hundred years before Darwin published a theory of evolution. Almost everyone in the early nineteenth century, including scientists, believed that God had created the different species just as they are. Coyotes, dingoes, and the whole lot of wolves and jackals were given their binomial name (i.e., genus and species names) by missionaries, explorers, artists, and other travelers — not knowing that in 1858 the definition of species was going to change.
After Darwin, the definition of species was very simple for evolutionary biologists: a species is a sexually isolated population of animals (or plants). Because wolves, coyotes, jackals, dingoes, and dogs are not only interfertile but regularly interbreed and hybridize, by definition they are all the same species. That should be the end of the story.
But of course, it is not. When did dogs diverge from wolves, if they did? Recent scientific papers have concluded that the divergence occurred 130,000 years ago or 30,000 years ago or 15,000 years ago. The correct answer is none of the above. Biologists in the nineteenth century classified every geographic variation as a different species (including people). It was okay to enslave some peoples because they were a different species. In fact, the dog has not diverged from the wolves, coyotes, or jackals or their relatives, according to modern evolutionary theory.
In addition, a statistician might ask the question a different way: how long ago did wolves, dogs, coyotes, and jackals share a common ancestor? Joseph T. Chang, a statistician at Yale University, worked out that solution for people. He argued that everybody has two parents and four grandparents and eight great-grandparents (fig. 1). By the time you get to ten generations you have a thousand ancestors, and at twenty you have a million, and at thirty, a billion, and at forty, a trillion, and at fifty, a quadrillion.
Well, there never has been a quadrillion people — so there were not enough people to make you, or alternatively, we all had to share ancestors. When was the time when everybody on the planet had the same ancestors? Fifty-four generations ago, everybody on the whole planet had the same grandparents.
That might be a thousand years ago. That might mean that with a twenty-year generation time, everybody in South Africa and everybody in Japan (or name your favorite spot) could trace their ancestry to William the Conqueror. If Marco Polo had left a surviving lineage (not everybody does or did), then everybody on the planet today could claim him as a direct ancestor.
Suppose we asked the politically incorrect question: Did white people evolve from black people or was it the other way around, and did they both evolve from Asian types? The argument would begin to sound absurd, as well it should.
If we asked the same question for the members of the genus Canis isn't it equally absurd? If fifty-four generations ago is the magic number for people, why isn't it the same for dogs? The fifty-four generations ago for the Canis (races) is 200 years. Two hundred years ago all jackals, wolves, dingoes, coyotes, and dogs shared the same ancestors.
Do we believe it? It is the not the job of a scientist to believe something but rather to test the hypothesis with the scientific method. Chang applied a brilliant statistical technique for figuring out the time to the most recent common ancestor. Does the method tell you when the various races of humans appeared on the earth? No. Is when they appeared the important question? No. Does the method tell when the first dog appeared on earth? No. Does it tell you how the first dog evolved? No. Is that an important question in understanding dogs? No.
Maybe the statisticians are wrong. Have they overlooked something? Is Chang's reasoning faulty? Chang's conclusion is such a spectacular way to look at the evolution of a species. It is fascinating. Our hypothesis starts, however, with the assumption that dogs, coyotes, and the rest are the same species. According to the original definition, that is true. And yes, by definition they are totally interfertile. (So for this chapter they are all the same species — maybe we will change our minds later.)
Historically, scientists classified dogs, wolves, jackals, and all into different species because of dozens of reasons — such as they live ondifferent continents or some are bigger or smaller or some have proportionately longer muzzles than others. Wolves have longer snouts than dogs — unless you are comparing wolves to borzois. Figure 2 (bottom) shows two canid skulls side by side. The one on the left is a wolf. The one on the right is proportionally shorter and wider, and those are traits that archeologists look for when they are looking for the first dog. But the skull on the right is not a dog. It is a juvenile wolf. You can tell that because the sutures in the juvenile wolf's palate are not all closed, which means the animal was still growing and changing.
You have to compare wolves to the average dog. What, then, is an average dog? And so on and so on. Speciation studies often measure and compare skulls. Yet our professor advised us to stay away from skulls when trying to delineate a species. Single skulls found here and there don't tell what the total variation of the population is. They grow at different rates according to the environment, showing seasonal or annual differences, as do the rings of a tree. Jackals and coyotes have very similar skulls but live continents apart. They occupy similar niches on those continents, and their skull morphology has converged on the best shape for doing the job.
Scientists need to create a better hypothesis. That is what scientists do. They test and retest hypotheses. If the data support a hypothesis, great — test it another way and see if you can falsify the hypothesis. For it to be science, it must be repeatable. It is mandatory to try to repeat it. If the data do not support the hypothesis, then change the hypothesis and test again.
Philosophically, scientists can never say they have found the truth. Some of us in the dog world are irritated by statements that scientists have found the truth about the origin of dogs — as if a single origin was identifiable. Look! We found the first dogs, the oldest dogs, the Adamand-Eve dogs. That is truly silly. The search must be for a population of dogs. At that point you have to ask the question, What is a dog, anyway? What are we searching for?
Supposedly, we all know what a dog is. Someone holds up a puppy and says, "What is that?" and you answer, "That's a dog."
Could you ever be fooled? Maybe. Maybe it is only part dog. Years ago we ran a team of sled dogs, and often when buying a dog we were informed by the seller that this dog is one-eighth wolf. We heard it so many times that we filed the statement under "myth," or "factoid." We became suspicious that a purported wolf ancestor is an advertising gimmick. We were expected to think that if the dog has a little wolf in it, it would be a better sled dog. Knowing what we know now, we should have said, "If it has a recent hybrid wolf ancestry, then we don't want it!" Why would anyone want any physical or behavioral characteristics of wolves on a sled-dog team? It would be trouble all the way. The sled dog — not the wolf — is the animal selected to pull sleds far and fast. Biologist Erik Zimen once put a "sled dog" team of hand-raised wolves together to pull him on a sled. He reports a host of hilarious happenings in his book The Wolf, a Species in Danger.
But there seems to be an appeal for a dog to be part wolf. One hears or reads about the wolf-like breeds. Statements abound that German shepherd dogs look more like wolves than other breeds or that Siberian huskies are an ancient breed, implying that both German shepherds and huskies are more closely related to wolves than are other dogs. Or perhaps they are descended directly from wolves as a breed.
Those are interesting but false observations because we know just when the German shepherd (at one time called the Alsatian wolf dog in Great Britain) became German shepherds and what breeds of dogs Max von Stephanitz crossed together, in the late 1890s, creating the fine sheepdog called the German shepherd. Imagine creating a wolf dog to herd sheep.
It is also known that Siberian huskies became Siberian huskies as a registered breed in the 1930s at Chinook Kennels in New Hampshire.
Similarly, the Anatolian shepherds were registered with the American Kennel Club (AKC) in 1996, using some of the dogs we had collected in rural Turkey as part of our livestock-guarding dog project a few years earlier. These are not "ancient breeds."
Most purebred dogs like the German shepherds, the Anatolian shepherds, the Siberian huskies, the Border collies, or the golden retrievers can be traced back to one or two or a handful of founding stock — all within the past 150 years. Those of us who are interested in the genetics of breeds know that if we take a sample of genes from purebred dogs, those genes couldn't possibly represent the diversity shown in the population of dogs from which the sample was chosen a hundred years ago. The Siberians and the shepherds and the golden retrievers were created by crossbreeding with other breeds. The makeup of those breeds has been carefully recorded. Which breeds make up our modern breeds is not a mystery.
And how successful they have been! In the United States now there are as many golden retrievers as there are wolves in the whole world.
(Continues...)
Excerpted from What is a Dog? by Raymond Coppinger, Lorna Coppinger. Copyright © 2016 The University of Chicago. Excerpted by permission of The University of Chicago Press.
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Table of Contents
Foreword by Alan M. BeckPreface
Part 1 About Dogs
1 What Is a Dog?
2 The World Is Full of Village Dogs
3 Why Do Village Dogs All Look Alike?
4 What Is a Niche?
Part II Behavioral Ecology
5 Behavioral Ecology of Dogs
6 The Cost of Building a Dog
7 The Cost of Feeding a Dog
8 The Cost of Reproduction
9 Avoiding Hazards and Their Costs
Part III That Special Relationship between People and Dogs
10 The Symbiotic Relationship
11 Dogs Adopt People (and Other Animals)
12 People Adopt Dogs
13 People Breed Special Dogs
14 Breed Genes Stray into the Village Dog Population
15 Dog Genes Stray Back into the Wild
Part IV Summary
16 Where—and Why—Are All These Dogs?
17 What Should We Do—If Anything—with All the Dogs?
Bibliography
Index