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By now it is generally accepted, although not entirely proven, that dogs evolved from wolves.
The best current theory is that, rather than humans stealing wolf pups and feeding and raising them at their campfires, some subset of wolves domesticated themselves. In this theory, the hunting pack was supposedly attracted to the edible scraps found in the humans’ kitchen middens—waste piles where hunter-gatherer groups tossed their old bones, discarded skins, and other refuse. Because the humans came randomly and often to dispose of these wastes, the wolves could not avoid contact with this large, strange, and unpredictable species. Over time, the wolves which demonstrated the most tolerance of human presence got the best and the freshest scraps. Fearful or hostile wolves kept their distance and got less of the good stuff.
This theory dovetails nicely with the work of Russian biologist Dimitri Belyaev, who bred foxes for tameness. Working sixty years ago, this dissident from Soviet biology began studying foxes in order to disprove Lysenkoism—the Lamarckian theories of Trofim Lysenko, who said traits acquired in life could be passed along to later generations. Stalin loved Lysenko’s ideas, because they proved that the Soviet state could, with sufficient force and enough reeducation camps, create a new “Soviet man,” whose selfless passivity and obedience to the Party would breed true and ensure Communist dominance into the future. Belyaev’s foxes—animals of the same family, Canidae, as dogs but not the same genus—gradually changed their physical appearance as well as their behavior. Through hormonal mutations associated with their tolerance of humans, the foxes over generations developed shorter snouts, rounder heads, and changes in coloring—among the same set of features that differentiates dogs from wolves.
How is this not evidence of Lysenkoism? Because in both cases—the wolves at the kitchen middens, Belyaev with his caged foxes—the changes depended on selective breeding for certain qualities. Both cases depended on various traits—fearfulness and hostility, or their lack, along with the associated neurochemical and hormonal differences—existing in the animal at birth. In the beginning of each transformation, these traits existed as random genetic mutations; in later generations, they were selected and reinforced through breeding. Wolves that could tolerate the human presence ate better and were more successful in mating; wolves that feared or avoided human contact either died out or returned to the forest. Belyaev’s fox pups that could tolerate being handled and liked being played with were allowed to breed at maturity; pups that snarled and snapped like wild animals were discarded from the experiment. Whether the selection is a natural circumstance of the environment around the midden or an intentional choice by a human breeder, the result was the same. A gradient of selection—a test for survival traits—was imposed on the breeding group, and the preferred traits were passed along to succeeding generations.
Every farmer does this, and it’s been going on since human beings first stopped roaming after the wild herds and settled on the land. We find a type of berry we like, plant it separately, control its pollination, and turn it into a brilliant red tomato—or a coffee bean with a particular flavor, or a luscious strawberry, or a conscious hybrid like the loganberry. We find a type of grass whose seeds are palatable and turn it into wheat—or corn, or any other type of grain. We find boars with the tenderest meats or wild horses with the strongest backs and turn them into farm animals. And dog breeders, like my aunt, find poodles with the best combination of form, disposition, and coloring and breed them to create a line of miniature and toy dogs that are exact replicas of their larger cousins. Other breeders find dogs that are attentive to human desires as well as quick and clever with sheep and turn them into herders and healers. We’ve been doing this for ten thousand years.
In most cases the original specimen remains, for the rest of us, obscure. The original and unattended tomato plant has either died out for lack of habitat or hides in a forest glade somewhere, unrecognizable to passing hikers. The original boar might lurk in the forest and become the target of occasional hunting parties, but for the most part the production of pork for barbecue ribs and savory sausages remains hidden from the average customer’s attention.1 Wild horses still exist in the American southwest, but they are only the feral descendants of domestic horses brought to this continent by Spanish explorers. The original, prototypical horse—Przewalski’s wild horse of the Central Asian steppes—had once almost gone extinct and has since been preserved only as a curiosity.
In these cases, the average person has no emotional attachments, either to the farmed pig or the feral boar. But in the case of wolves and dogs we have both attachments and opinions.
Wolves exist in the public imagination as noble creatures. They are bound to the pack, loyal to their mates, fierce in their hunting, sleek in appearance, and bold in their status as predators. Although wolves might be the subject of childish fears born out of fairytales and horror novels, for most people they the emblem of everything that is implacably wild and free—and true to itself. The wolf has its own nature.2
Dogs exist in our homes as loving companions. They are biddable, fawning, loyal to our family, suspicious of strangers, and gentle with our children. Many people sleep in the same bed with their dogs. The average dog, with its rounded head, floppy ears, and wagging tail, is now more our court jester and emotional pillow than our guardian and defender. Yes, a large dog can be trained to become fierce and unfriendly, but they do so only in response to human bidding. Their nature is to trust and depend. The dog has the character we give it.
For many people, the transformation from wolf to dog is a travesty, if not a tragedy. We—or our table scraps—have created something unnatural, in defiance of nature. We have taken an animal that was once self-sufficient and uncompromising and turned it into a beggar and a clown. But the wolf of our imagination would make a poor playmate for our children, have no interest in defending our homes, and would not sleep in our beds or even doze in our strange and dangerous presence.
For others, the wolf in the wild is a menace to livestock, a danger to house pets and babies, and at the very least an unpredictable presence around ranches and farms. There are still people who will shoot a wolf on sight, even while environmentalists are trying to restock and encourage them in habitats where they once roamed. The wolf is a topline predator in an environment that offers ever fewer prey animals and so has become a nuisance.
None of these considerations, of course, is of any concern to either the wolf or the dog. It is performing in its environment and reacting to stimuli exactly as its genes were selected to do. It is fitted for survival under the circumstances in which it finds itself. And this is perfectly natural.
Wolves and dogs are both still fresh in the human consciousness and imagination. They are a reminder that our species has changed the natural world in ways that we believe are both good and bad. We bend species to our will. We change forest and field into plantation and farmland. We occupy so much of the land and use so much of the rivers flowing across it that, in many areas, “nature” is a thing that must be preserved behind a fence.3
Which is preferable—wolf or dog? That depends, like so much else, on your viewpoint and your purpose. I for one am glad that the distinction exists. I am proud that we have had a hand in engineering a companion who can remind us to be kind to creatures that are different from and less capable than ourselves. And I am pleased that we can still value the wolves of our imagination while petting the dog that stands at our side.
1. The visceral distinction between husbanded animals in production on the farm and their prepared flesh on the customer’s fork is linguistically preserved in English as a relic of the Norman Conquest. The words “pig” and “cow,” from Middle English, are retained for livestock, while the words “pork” and “beef,” from Old French, are kept for meats in the kitchen and on the table. This verbal distinction came about when the Anglo-Saxon field hand still worked to raise the food for his Norman overlord.
2. We have friends who once had a pet dog that had been bred from a line intended for pulling sleds in races like the Iditarod. Its genetic mix was part Siberian, part husky, and part wolf—the latter added for endurance in long races. This particular animal was devoted and loyal to its humans, but it did maintain a certain aloofness and dignity which the owners attributed to its wolf nature. For example, the dog would enjoy cuddling and being petted but would not allow you to touch it with your feet. The animal seemed to sense that feet were different from hands and represented an indignity.
3. However, the people who think we’re “destroying the planet” need to get out of their apartments in Berkeley. Great tracts on this continent—and on most of the others—still manage themselves pretty well under natural conditions. Humans, for the most part, live clustered along the coasts and in the river valleys. We are still thin on the ground over much of the Earth.