OF DOGS AND WOLVES
One day in late November 1989, while setting out on a hike with his wife, Eve, in Hungary’s Kékes Mountains, Vilmos Csányi (pronounced Chai-nee) spotted a stray dog. The dog—small, fuzzy-furred, and male—proceeded to follow them. After about five miles, the dog seemed to tire, so Csányi picked him up and carried him the rest of the way. The next day, Csányi, Eve, and the dog—whom they had named Flip—returned to the Csányis’ home in Budapest—a day earlier than they had originally planned. The inn where they were staying wouldn’t allow dogs in the room—and now they had one. Or the dog had its humans. Either way, the unexpected friendship also unexpectedly opened the door on a new field of research: the study of the minds of dogs.
At the time that he and Flip found each other, Csányi was the head of the Ethology Department at Eötvös Loránd University in Budapest. He and his students were focused on the learning abilities and mechanisms of the paradise fish and had made several major discoveries. Their research was well known and highly regarded, and they had an excellent international reputation.
“But this fish research was becoming very boring,” Csányi told me one evening in February 2009 over tea in his book-lined study in his Budapest flat, with his elderly blond, mixed-breed dog, Jerry, at his feet. Flip had died some years before, and Csányi was now silver-haired and retired. “We were repeating our fish experiments with mice, and we were publishing good papers, but I felt we needed to change our focus.”
After bringing Flip home, Csányi had started a diary about him. (He included Jerry after acquiring him eight years later.) He noted that Flip appeared to pay close attention to what his humans were saying and to understand what was about to happen, such as a walk, a car ride, or the arrival of food. He made notes about things like how Flip would make him realize there wasn’t any water in Flip’s bowl; or how Flip would ask him questions by sitting in front of him and looking at him “questioningly”; or how Flip would use his nose to poke Csányi in the morning to rouse his master from bed. He also began to share his dog stories with the members of his lab.
“Yes! Csányi would come in and tell us some unbelievable story about Flip, and ask us, ‘Why do you suppose he did that?’ ” recalled Ádám Miklósi, one of Csányi’s former students. “And then he would say, ‘You boys figure out an experiment to test that, to show why Flip can do that.’ Everyone would have a very long face. Because in those days, no one would think that you are a serious scientist if you are studying dogs.”
Dogs weren’t always viewed so negatively by animal cognition scientists. Darwin peppered his books on evolution with examples of dogs to illustrate his concepts and turned to them repeatedly in his study of the universality of expressions and emotion in humans and animals. The pioneering behavioral scientists Ivan Pavlov, William T. James, and D. O. Hebb also found dogs to be fine subjects for their studies; while John Paul Scott and John Fuller investigated the links between dogs’ genetics and their social behaviors in a long-running project that they summarized in their classic 1965 book, Genetics and the Social Behavior of the Dog. Yet by the 1970s, dogs were being shunned largely because cognitive scientists and ethologists decided that domesticated animals were artificial and not as intelligent as their wild brethren. As supporting evidence, scientists pointed out that dogs’ brains are about 25 percent smaller than those of wolves, their immediate ancestor. Presumably, dogs lost some degree of intelligence in exchange for living a softer, less challenging life with us.* Researchers also thought that the bond between human and dog made it impossible to study them objectively. Those few who braved going against the tide were snubbed. “My colleagues said, ‘Why don’t you study real animals?’ ” Marc Bekoff, a cognitive ethologist and the author of several books about animal cognition, remembers being asked when he first proposed studying dogs’ play behavior in the 1970s. These days, Bekoff’s studies are widely cited.
Csányi never worried about whether his lab would be derided for studying the minds and behaviors of dogs. “You would never make a scientific discovery if you thought only of your colleagues’ reactions,” he said. Besides, he was as intrigued as Darwin had been by the transition from wolf to dog, and because so few people were studying dogs Csányi thought canines offered a rare research opportunity. “Of course, I saw the many dark expressions [on my students’ faces] when I would tell them some story about what Flip had done that weekend,” he said. “Okay, that wasn’t science. But these kinds of things, my stories, eventually gave us ideas for experiments—good experiments.”
Experiments, it should be said, that changed the science of animal cognition and ethology, helping to expand both fields. Today researchers embrace the study not only of dogs but of domesticated animals in general, which are no longer considered simply dumbed-down versions of their feral ancestors. Dogs, in fact, are now regarded as excellent subjects for understanding how evolution can shape and transform a species’ brain and for studying the mental building blocks that involve social cognition. Research programs and laboratories devoted to dog cognition have sprung up at universities from Australia to Japan, and there are even special dog cognition conferences.†
Csányi’s students, though, could not foresee these changes. All they knew was their professor had an idea that he wouldn’t stop talking about—that in order to live with humans, dogs had to give up some of their wolfish ways and develop new social skills. They had to become loyal to their new group—humans—and accepting of our rules. Most of all, Csányi argued, they had to become adept at reading and responding to human communication cues. In short, they had to become mentally more like us. Csányi then proposed a bold and overarching hypothesis to guide the lab’s studies: that the transformation of the wolf, Canis lupus, to the dog, Canis familiaris, was a better model for understanding the evolution of the human mind than the transformation of chimpanzee to human.
“Csányi’s main hypothesis was that the minds of dogs, because they were shaped by humans, resembled the minds of their creators or inventors, so we could learn a lot about the human mind by studying those of dogs,” Miklósi said. “It was a big idea—a great idea—but of course we didn’t see it that way.”
When Csányi broke the news in 1994 that the lab would be switching to dogs, “the great idea” struck Miklósi “actually as a bad one, in fact, a terrible one,” he said, recalling his despair. “I was just at the beginning of my career, and I thought for sure this would be the end of it. I was sure no one would take us seriously. I remember thinking, ‘My God, are you crazy?’ That’s what I thought, although, of course, I didn’t say it. And I wasn’t sure what we were going to do; how were we going to study dogs?”
THE IDEA THAT DOGS are more like us than they are like wolves goes back at least to Darwin, who wrote about their transformation, “Dogs may have lost in cunning … yet they have progressed in certain moral qualities, such as affection, trust, worthiness, temper, and probably general intelligence.” Darwin, who loved dogs and owned many, regarded them as one of the best examples of the power of both natural and artificial selection—an animal that through its relationship with us had gained some emotional and cognitive similarities to humans, yet retained the physical qualities of its predatory ancestor. They were his prime example of how animals, other than humans, also experience “pleasure and pain, happiness and memory.” Dogs possess imaginations, Darwin believed, and the power to reason, to feel love, jealousy, pride, and something akin to a conscience and religion. He reached his conclusions simply by observing his own dogs and paying attention to the reports of other dog owners—all anecdotal findings in today’s world, and not acceptable to modern science journals. “Nonetheless,” as Erica Feuerbacher and C. D. L. Wynne noted in an article about the history of dog cognition studies, “his ideas have often proved correct.”
Csányi’s students, of course, would have to use more rigorous methods than Darwin’s astute but largely anecdotal observations. For Miklósi that was one of two problems about the challenge of studying dogs. No scientific standards or methodologies were then in place for studying dog cognition. It was one thing to raise and study fish in a laboratory, but how would Csányi’s students obtain enough dogs for research projects that required at least fifteen subject animals for a proper statistical analysis? The second problem was more personal. Miklósi was not a dog lover. He had never had a dog—either as a child or as a university student. He does not own one today, even though after Csányi retired Miklósi moved into his mentor’s position, becoming head of the Ethology Department and director of the Family Dog Lab. All his life, Miklósi, who is also the author of Dog Behaviour, Evolution, and Cognition, has never had a dog of his own. Miklósi loves cats.
Miklósi, who was in his midforties when we met, reminisced about his initial despair over Csányi’s plan while we talked in his office in the university’s biological sciences building, a simple cement-slab structure overlooking the Danube River. Outside, it was a wintry day, the ground frozen, the sun shining weakly on the river. Inside, it was comfortable enough to keep a tropical freshwater turtle alive. Miklósi had one on his credenza, housed in a shallow aquarium.
“Yes, I know it amuses everyone that I’m not a dog person,” he said when I smiled. “I’m not one of those people whose eyes go all soft and crinkly whenever they see a dog. My daughter is. So we do have a dog, a sheltie, at home. But Scottie is her dog.”
Miklósi had given me a quick tour of the Family Dog Lab when I first arrived. It was easy to tell it was a dog lab because there were dog owners in the hallways, and dog-owning professors, and dogs in all the offices that we passed—until we got to Miklósi’s. The only animal (aside from us) in his tidy, carpeted room was the turtle. Perhaps, I speculated aloud, he had a turtle because with all the dogs around the lab, it didn’t make sense to keep a cat.
“No, the turtle is my son’s,” Miklósi said. Miklósi had brought it to his office because he thought the turtle—whose name is Pillow—was being neglected. Here, with all the people coming and going, Pillow had a more stimulating environment than in his son’s bedroom, where he was often just a lonely turtle stuck on a shelf.
Miklósi has a lean build, a mustache and small goatee, and straight, light brown hair that falls over his ears and forehead and that he sometimes has to brush away from his eyes. His fingers are long and slender, his speech is fast (even in English), and his way of moving is quick, almost catlike. If I’d seen Miklósi in a police lineup of biologists and ethologists, I would have picked him as the statistician or computer modeler—someone designing projects with virtual or imaginary animals, not the one working with living creatures. Yet he is actually the kind of person who worries about a turtle’s state of mind. And so, despite his wariness of dogs, and his inability to “have a close bond with a dog,” he’d found a way “to appreciate them,” as he put it, and then to study them.
After deciding that their lab would focus on dogs, Csányi made sure there was no turning back by having all the aquariums and fish supplies removed; the only remaining signs of the lab’s previous incarnation are some unused sinks and tiled backsplashes. Miklósi and his fellow postdoctoral student József Topál, who is now at the Institute for Psychology at the Hungarian Academy of Sciences, began reading the scientific literature on canine behavior, looking for any studies that might help them devise an experiment.
“We did nothing really but read for the first three years,” Miklósi said. “We had nothing to publish. All of our first ideas were stupid. It took a lot of time to figure out what we wanted to do and could do, and then how to do it.”
Csányi ended up selecting the first experiment—one that would test the long-standing scientific assumption that dogs, with their smaller brains, are not as smart as wolves. Very few studies comparing dogs’ and wolves’ cognitive abilities had ever been done; one of the most cited involved only four young wolves and four equally young malamutes. The canids were given the task of figuring out how to open a gate after watching a person do it. The wolves solved the problem immediately; the dogs never even tried, despite being shown repeatedly how to remove the latch.
“Professor Csányi really disliked this study,” Miklósi said. “He said it was easy to explain because the dogs were well trained and well behaved and knew they shouldn’t open the gate unless they had their owner’s permission to go out. They knew there was a rule, and they were obeying the rule.”
At least that was Csányi’s hypothesis. To prove that the dogs were following a rule, the researchers needed to test various breeds of dogs of differing ages and genders, so that their results would apply to all dogs, not just those of a particular type. Where were they to find so many dogs? Csányi had already ruled out having a group of lab dogs kenneled at the university; that would have been expensive and unkind to the dogs. The researchers briefly considered using canines from a shelter but discovered that the dogs competed to be chosen for an experiment—and those that were frequently selected were later punished by the others. (“Dogs,” Csányi would conclude about this behavior, “do not like exceptions.” In other words, dogs have a sense of fairness.) As an ethologist, Csányi wanted to use healthy dogs that were normal and living in their natural environment—the “wild jungle” of the family home, as he called it. He also realized that he would need owners to participate because the dogs would perform best if they received directions from their masters. Finally, he turned to a dog agility club for his human and canine participants. (Csányi’s method of using dogs and their owners is now followed at nearly all dog cognition labs.) Of course, every dog owner knows that his or her dog is smart, and in no time, the scientists had plenty of applicants.
Csányi’s team devised a modified version of the gate-latch test. They placed cold cuts into ten dishes with long handles and slid the dishes beneath a low wire fence that ran parallel to the floor. After calling a dog and its owner into the room, one of the researchers demonstrated how he could get the food by pulling on a dish’s handle. He then stepped aside, and the dogs were given three minutes to decide what to do. Some of the test subjects were outdoor dogs, used to being on their own, and so more independent than dogs that lived inside a family home. Most, but not all, of the outdoor dogs didn’t hesitate; they immediately copied the demonstrator and solved the test. The few outdoor dogs that did not grab the handles were dogs that were very closely bonded with their masters. Tellingly, all the dogs that lived inside with their human families did nothing, aside from frequently glancing at their owners. Not one tried to touch the handle of one of the dishes. Only after their owner spoke to them did these dogs do so. Even then, some of the dogs kept looking at their owners, seeming to want their help.
“That was our first breakthrough,” Miklósi said. “It showed that dogs could solve problems as wolves do but they also have this special desire to cooperate with their masters, to follow a command. They want to work with us.”
People often talk about the pack nature of wolves, Miklósi added, and how wolves cooperate on the hunt and in raising their pups. So the tendency to cooperate is there in dogs’ ancestors. But to cooperate with an entirely different species, one not closely related on a genetic level—and to seek that cooperation above all else—means that something has fundamentally changed in the brains of dogs.
As a dog owner, I wasn’t surprised to hear the results of these tests; I doubt if most dog owners would be. What did surprise me was learning that Csányi and his team had published this study in 1997: in the late twentieth century, science had finally rediscovered the mind of the dog.
The Hungarians were soon on a roll. In 1998, the team published two more landmark papers in respected and high-profile science journals. One investigated the idea that the relationship between dogs and humans is a “social attachment”—a term that psychologists first used in the 1970s to describe the strong bond between mother and child. While other researchers had suggested that dogs behave as if they had a social attachment to humans, the Hungarians were the first to confirm this via their experiments. They revealed, for instance, that dogs that are strongly bonded to their owners experience separation anxiety when their masters leave them, just as young children who are strongly bonded to their mothers do when their mothers step away. Tightly bonded toddlers and dogs also respond similarly when mothers or owners return, racing forward to greet them and leaping and cavorting with joy. “The bonding processes of dogs and humans are truly extraordinarily similar,” Miklósi said, “and they last throughout both species’ lifetimes.”
The second paper demonstrated that dogs pay close attention to what humans are pointing to or looking at—something that chimpanzees have great difficulty doing. “We showed that a dog can read and use a person’s social cues,” Miklósi said, even though dogs don’t have fingers for pointing and never make a pointing gesture with their legs (although some breeds, such as pointers, do point with their entire bodies).
In this test, which is now regarded as a classic, the scientists asked a dog’s owner to hide food in one of two scent-proof containers. The owner then looked at or pointed to the container with the food. It was up to the dog to use this cue to understand that his owner was in essence telling him that he knew where the food was hidden and that the dog would find it if the dog followed his owner’s finger or eyes to the right location. No other animal had been shown to have this ability, so Miklósi was braced for attacks when the study was published. Instead, another team of scientists in the United States made the same discovery independently, and the two papers appeared almost simultaneously.‡
“It meant that we weren’t alone in doing this research; there were other scientists who were thinking along these same lines,” Miklósi said. “That was when everything began to change. Of course, some people were skeptical about dogs being able to do this [to follow human pointing cues], but because there were two papers saying the same thing, it was difficult to argue against us.”
By the time of my visit, Miklósi, Topál, and their colleagues had published more than seventy papers on the minds of dogs. From their studies, we now know that dogs long to be with humans almost from the moment they open their eyes. In tests at the lab, four-month-old puppies given a choice between going to a human companion and going to another dog preferred the person. Young wolves that members of the lab had hand-raised showed no such preference. The researchers discovered that even adult dogs living in rescue shelters rapidly form attachments to people; it took a mere thirty minutes of interaction between a person and an adult shelter dog for the dog to begin forming a bond. It’s rare in most species—other than humans—for adults to form attachments, and to the Hungarians, this was another indication that dogs possess humanlike traits.
In another test of dogs’ social learning capabilities, the scientists showed that dogs can imitate a person’s action, much like children playing Simon Says. The volunteers would stand in front of their dogs and turn in a circle, or jump up, or place an object in a container, while calling out enthusiastically in Hungarian, “Do as I do!” Most of the dogs readily performed the action, succeeding as well as sixteen-month-old children who were given the same test.
The Hungarians revealed, too, that dogs have a sense of what’s “right” and “wrong” and can follow our human rules, a social skill that helps to strengthen the bonds within a group. Dogs even understand that human rules aren’t necessarily rigid; they can be flexible—and humans inconsistent, sometimes telling them that it’s okay to get on the couch and other times demanding that they get down.
Perhaps most surprisingly, with their colleagues at the Hungarian Academy of Sciences, the scientists showed that dogs will follow human cues on certain tasks despite evidence right in front of their eyes that they are making the wrong decision. In this test, a researcher repeatedly placed a ball in Box A, while making eye contact with the dog and explaining that he was hiding the ball there: “Rex! Watch, Rex. I’m hiding the ball here.” Then Rex would be allowed to find the ball. In the next phase, with Rex watching, the experimenter silently moved the ball to Box B. Where would Rex now search for the ball? In Box A. Human toddlers make exactly the same error because both dogs and young children learn by paying attention to the social cues adult humans give them, rather than by making their own judgments—one of the most striking examples of how similar the minds of dogs have become to those of humans.§
As a result of the Family Dog Lab’s experiments and tests at other dog cognition labs, dogs are now hailed as a natural experiment, one we humans set in motion when we brought dogs into our homes and lives some fifty thousand or more years ago. Many researchers now agree with Csányi’s initial belief that dogs and humans represent an unusual case of what is termed convergent evolution, because although dogs and humans have entirely different ancestors, we share numerous behaviors and traits—particularly the desire to work together to accomplish a task.
“It has been a complete shift,” Miklósi said. “I’m as surprised as anyone, because really, I didn’t think we were going to make any discoveries. And from what we’ve discovered, we can say some general things now about dogs. I may not be a dog lover, but even I can see the special, dynamic relationship dogs have with us. With cats, we have a very simple social relationship; it’s not so much about doing things together. But that is really at the heart of the dog-human relationship. They are companions, yes, but they are also with us in working relationships, like herding, guarding, or going to war. We do these things together with them. Cats hunt for us, but we don’t hunt with them. It’s a big difference.”
Miklósi glanced at his watch. The student of one of his colleagues was about to start an experiment. We walked down the hallway to the office of Péter Pongrácz, the student’s supervisor. Miklósi tapped on the door and cracked it open a few inches.
“It’s okay,” Pongrácz said. “My dogs will stay.”
Miklósi and I agreed to meet later, and I slipped inside Pongrácz’s office, where four dogs lay curled up next to his feet. They lifted their heads and ears, studying me. One was chestnut colored, the others were completely black; all were medium-sized, with long, pointed noses and curly body fur, although the fur on their faces was smooth.
“These are my dogs,” Pongrácz said. “They are Mudis, Hungarian shepherds, and they are very smart.”
Pongrácz was tall and beefy, with a long, oval face and dark blond curly beard, which made him look rather like a blond Mudi. His dogs watched us briefly, then lay back down.
Were they going to take part in the test? I asked.
“No. We use them to try out our ideas for experiments. But then for the real test, we want dogs that have never seen the experiment, so that we can show they have not been trained.”
Pongrácz was investigating why dogs bark, what they might be communicating. Wolves bark, too, but only to warn or to protest. Miklósi had told me that dogs “invented barking as a means of communicating to us as much to other dogs” and that they “can modulate the frequency or pulse” to signal fear or feeling lonely or playful. One of Pongrácz’s previous studies showed that humans can easily identify the differing barks of a lonely, fighting, or playing dog. “That means that a dog’s bark is often directed at us to convey the dog’s inner state,” Pongrácz said. “Maybe they do this because they live with a very talkative species.”
Pongrácz’s student, Tamás Faragó, would be giving the test, which was designed to further investigate the communication between dogs and people. He and Pongrácz spoke briefly in Hungarian, and then Faragó said in somewhat halting English, “Please, join us.”
In the hallway outside, a middle-aged woman had a bright-eyed Cairn terrier on a leash. “This is Kopé,” Faragó said, introducing me first to the dog and then to Kopé’s owner. Faragó directed us into the lab room, where he had arranged a small cage that was covered with a cloth. Inside the cage was a concealed tape recorder, and outside lay a large, tempting bone.
Faragó stood next to me in the back of the room and directed the owner to let Kopé off his leash. Immediately, Kopé spied the bone and made a beeline for it. But just as Kopé reached the bone, Faragó used a remote trigger to start the recorder. From the cage came the deep-throated growl of another dog, and Kopé froze in place.
“That’s a food-guarding growl,” Faragó whispered to me. “As soon as a dog hears that, he knows he better leave that bone alone.”
When the unseen dog growled a second time, Kopé, looking unnerved, ran halfway back to his owner, wagging his tail. He peered up at her face and then looked back over his shoulder at the bone.
“He’s asking for help,” Faragó explained. “ ‘Come on, Mommy, help me get that bone. Let’s do it together.’ ”
And that, Miklósi said when we met up again that afternoon, is what is fundamental to dogs’ cognitive abilities: their strong desire to work with and for us, and their ability to communicate even without language—with nothing more than a soulful look.
“We’ve joined forces with the dog,” Miklósi said. “We’ve brought their minds into our lives, and into our work as companions and assistants, as our collaborators. Looking back now, at when we first started, I have to say I’m surprised that no one wanted to study dogs before, or thought dogs were mindless. These days, we understand dogs in a completely new way. It’s like having new glasses on.”
WITHOUT THE DISCOVERIES of Csányi and his students, scientists might not have paid attention when a border collie named Rico appeared on the popular German television show Wetten das? in 2001. He knew the names of some two hundred toys, and to the delight of the television audience he enthusiastically fetched them by name from his collection. Julia Fischer, then a postdoctoral fellow at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, happened to be among the millions of viewers. She told her fellow student Juliane Kaminski about Rico, and the two arranged a meeting to test the collie. They discovered that Rico possessed an uncanny language ability: he could learn and remember words as quickly as a toddler, they reported in Science. When the scientists placed a new toy among his familiar toys and gave it a new name, Rico managed by using some type of simple logic (“I know the others, but I’ve never seen this one, so it must be it”) to almost always retrieve the new toy. Even after not seeing the toy for a month, Rico could successfully fetch the toy in half of his trials. Without repetitive instruction, he had integrated the toy’s name into his vocabulary.
Other scientists had shown that two-year-old children—who acquire around ten new words a day—have an innate set of principles that govern how they learn and remember these. The capacity for recalling new words is one of the key building blocks in language acquisition. Fischer and Kaminski suspected that the same principles guided Rico’s word learning and that the technique he used for learning and remembering words—termed “fast mapping”—was somewhat similar to that of humans.‖
To find more examples, Fischer and Kaminski read all the letters from hundreds of people claiming that their dogs (and in some cases, cats) had Rico’s talent. In fact, only two—both border collies—had comparable skills. One of them—whose owner asked me to call her dog by the pseudonym Betsy to protect her from “dog haters”—has a vocabulary of more than three hundred words.a For abstract thinking, we employ symbols, such as words, letting one thing stand for another. Is this what the dogs were doing, too? That’s what Kaminski and Tempelmann hoped to discover through their tests with Betsy.
“Even our closest relatives, the great apes, can’t do what Betsy can do—hear a word only once or twice and know that the acoustic pattern stands for something,” Kaminski told me during a visit with her and her colleague Sebastian Tempelmann to Betsy’s home in Vienna in 2006. They were giving Betsy a fresh battery of tests. Kaminski petted Betsy, while Tempelmann set up a video camera.
“Dogs’ understanding of human forms of communication is something new that has evolved,” Kaminski explained, “something that’s developed in them because of their long association with humans.” Although Kaminski has not yet tested wolves, she doubts they have this aptitude. Because the skill has been found only in border collies, she thought that it was somehow related to their traditional herding jobs—that over the years shepherds had selected those dogs that were the most highly motivated and attentive listeners.
How similar are the border collies’ language skills to those of humans?
Betsy’s owner, who asked to be identified by the pseudonym Schaefer, summoned Betsy. She obediently stretched out at Schaefer’s feet, eyes fixed on her face. Whenever Schaefer spoke, Betsy tipped her ears forward and attentively cocked her head from side to side.
Kaminski handed Schaefer a stack of color photographs and asked her to choose one. Each image depicted a dog’s toy—such as a teddy bear, a mini-Frisbee, or a plush toy lobster—against a white background. Betsy had never seen these toys, and of course they weren’t actual toys; they were only images of toys. Could Betsy connect a two-dimensional picture to a three-dimensional object?
Schaefer held up a picture of the rainbow-colored mini-Frisbee and gave it a name, “Frisbee.” “Look, Betsy,” she said in German, as if speaking to a young child. “This is Frisbee. Frisbee.” She said the name several times, tapping the picture and urging Betsy to look. Then she placed the photo face down behind her and told Betsy, “Now, go find Frisbee. Find Frisbee.”
Betsy ran into the kitchen, where the Frisbee was placed among three other toys and photographs of each toy. She came running back triumphantly with the Frisbee photograph, and after Schaefer dispatched her again, brought back the Frisbee itself.
“It wouldn’t have been wrong if she just brought the photograph,” Kaminski said. “But I think Betsy can use a picture, without a name, to find an object. It will take many more tests to prove this, and even then, there will be critics because this is a kind of abstract thinking.”b
In his observations about dogs, Darwin noted that they had probably evolved something he termed “general intelligence” by becoming domesticated. Dogs had a mental flexibility he thought wolves did not possess. They also have very breed-specific talents, such as the border collies’ language abilities, or the now extinct “turnspit dog” that Darwin mentioned, whose task was to run inside a treadmill attached to the meat-roasting spit on the family hearth. Dogs’ willingness to help us in so many varied ways is perhaps the most remarkable thing about them—and certainly a key distinguishing feature between them and their wolf ancestors.
“Some people say, ‘Oh, well, the dog is just another domesticated animal,’ ” Miklósi had said to me toward the end of my visit at the Family Dog Lab. “But it is not. Dogs were the first domesticated animal, and not just by one thousand years, but by ten thousand or twenty thousand years, maybe longer. That is a huge advantage. And then they were taken very rapidly by people everywhere, I think via trading. You can imagine how everyone would want this precious new, little thing.”
The first known dogs were not, in fact, little, although in time we developed smaller breeds. Although scientists argue about when dogs were first domesticated, recent discoveries suggest that the earliest dogs were large, powerfully built animals.c In 2012, paleontologists working at Predmostí, a site in the Czech Republic that dates to about twenty-seven thousand years ago, reported the discovery of the remains of three dogs from an encampment where people once hunted mammoths. Judging from the skeletal material, these dogs would have weighed between seventy-five and ninety pounds, and stood about two feet tall at the shoulder—not as big as Eurasian wolves, but certainly the size of today’s German shepherds. Intriguingly, three of the skulls were perforated—someone had punched holes in them to remove the brains—and one held a piece of mammoth bone in its mouth. The scientists think that someone—most likely one of the mammoth hunters—had placed the bone in the dog’s mouth as part of a ritual to “feed” the soul of the dead animal. Perhaps the hunters had also removed the dogs’ brains to release their souls, or more practically, to use for tanning hides. Even older dog remains, dating to thirty-two thousand years ago, have been uncovered in Belgium, while the thirty-three-thousand-year-old skull of an “incipient dog” was reported from a site in Siberia’s Altai Mountains in 2011. These, too, were large animals, yet clearly distinguished from wolves by their shorter and broader snouts and crowded teeth.
What would these early dogs have been like? How much do dogs actually differ from wolves in their minds and behaviors?
While the Hungarians had taken a stab at this question in 2001, Miklósi urged me to visit another group of scientists who were hand-raising wolves in Austria to see the difference for myself.
WHEN I FIRST MET ZSÓFIA VIRÁNYI at the Wolf Science Center in Ernstbrunn, Austria, she looked as weary and rumpled as anyone would who’d spent the night sleeping—or trying to—with six four-month-old wolf pups in a barn. Bits of straw and lint clung to her clothes, her eyes were puffy and rimmed with dark circles, and her curly, honey-blond hair was not yet combed. As she walked to the center’s gate to greet me, she pulled a piece of grass from her jacket and dusted off her pants. “Well, this is how it is with wolf puppies,” she said. She spoke with the voice of experience, since, while earning her doctorate in ethology, she’d worked with Miklósi and his colleagues at the Family Dog Lab on their study of hand-raised wolves. Indeed, Virányi knew wolves almost better than she knew dogs. Not only had she lived with, bottle-fed, and slept with a wolf puppy during that first experiment, she’d subsequently helped raise a dozen more wolf pups for this new project; she’d also studied captive wolf facilities throughout Europe and the United States while researching the best methods for managing wolves in captivity.
Virányi’s German colleague Friederike Range, who’d driven me from Vienna to the center, nodded in sympathy as Virányi rubbed her eyes. Even though Range had not spent the night sleeping with the wolves (they were old enough now that the wolf raisers could alternate nights), she also looked exhausted—the result, she’d told me on our drive, of the four months’ nonstop work of hand-raising the pups.
“You never get a full night’s sleep,” Virányi said. “Six hours, maybe. They’re very restless in the early night and early morning. For them, it’s time to hunt. And in the middle of the day, when you want to do something with them, they only want to sleep. Their natural rhythms are very different from ours—and from dogs.”
Range and I had arrived just after 8 a.m., so the pups were still wide awake. They’d been sitting with Virányi and Tódor, her black-and-tan, mixed-breed dog, inside a fenced enclosure at the privately owned Ernstbrunn Game Park about thirty miles north of Vienna. At the time of my visit in September 2009, the Wolf Science Center’s headquarters were housed here in two old stone buildings that had once served as the stables for an aristocrat’s estate; today, they’re located in brand-new buildings also inside the park. In addition to the wolf pups, three adult wolves that the scientists had also hand-raised lived in another outdoor arena, amid the park’s rolling oak woodlands. Deer, wild boar, and wild sheep freely roam the grounds, but the wolves are strictly confined. The three oldest wolves had come to the center from a zoo in Austria; two of the pups were brought from a zoo in Basel, Switzerland; and the other four pups came from a game park in Montana. All had been separated from their mothers and littermates before they were ten days old so that they would not develop a wariness of humans.d Their round-the-clock care and feeding had been taken over by Virányi, Range, Kurt Kotrschal, a zoologist at the University of Vienna, and a crew of volunteers as part of a remarkable experiment to investigate the relationship between wolf, dog, and human.
“We want to understand this triad,” Range had explained on our drive, her English rising and falling with the soft inflections of her German accent. “People say many things about wolves, dogs, and humans—how they’re alike or how they’re different. But the truth is we’re only at the beginning of understanding the minds of wolves and dogs, and understanding how humans changed the wolf to make the dog. In fact, we’re at such a basic level we have almost everything to learn.”
By hand-raising wolves and a separate group of dogs, the scientists could track, test, and compare the cognitive development of both animals—something that had never been done in such a controlled manner, or with dogs and wolves that had comparable upbringings from their pup stage into adulthood. (As of July 2012, the scientists had hand-raised eight more wolf pups and thirteen dog pups in the same way.) And with those results in hand, they could then see if dogs through domestication had truly become more humanlike in their minds and behaviors.
At the center, Range, with her border collie, Guinness, in tow, had led the way to the wolf pups’ enclosure to introduce me to Virányi. As soon as they spotted us, the pups yelped with excitement, an adult wolf howled in response, and Tódor and Guinness barked. Virányi unlocked the enclosure’s gate to let herself and Tódor out, but she shooed away the pups and carefully refastened the lock, then checked it again, before turning to shake my hand.
The wolf pups—one black, one blond, and four mostly tan and gray—stood on the opposite side, whining and pawing at Range and Guinness. The pups noticed me, too, but gave me only brief, wary glances. If I looked their way, they dropped their heads and peered up at me with their shoulders hunched, bodies angled, and legs askew—the pose of a cautious but curious animal.
“Yes, there’s a stranger here,” Virányi said to them. “Someone new to meet this morning.” To me, she said, “New people; new things—they always get a little bit anxious.”
“They’ll warm up to you,” Range said. “Just move slowly; let them come to you.” She knelt close to the fence and called the wolves’ names. “Hello, Nanuk and Yukon. Why didn’t you let Zsófia sleep last night? The black is Apache; the blond is Cherokee. And those,” she said, pointing at the last two, “are Geronimo and Tatonga.” The scientists used “Indian names,” they said, because their pups—even the two from the Swiss zoo—were North American gray wolves, and the names were meant to honor their heritage.
“It’s good for them to meet new people,” Range said. “It helps them learn how to form relationships with people, which is what we want. We aren’t trying to be part of their pack, but we want them to respect us and to follow our rules in certain situations. But we also respect them, and so follow their rules in other situations.” For instance, when inside the wolves’ enclosure, the scientists consider themselves as the guests of the young wolf pack and are careful to never compete with them over objects or food; they also don’t take sides in any of the pups’ disputes but let them sort out their contests over their dominance hierarchy. “This way we can ask the wolves to do things, more or less like you would ask a dog.”
As we talked, I watched the pups. Perhaps our ancestors had brought young wolves like these into their camps. If you just glanced at them from a distance, you might think they were German shepherd puppies. They were about the same size and build, with legs that seemed too long for their bodies. They nipped and growled at each other, and tumbled about as puppies do. But there was something else about them that I couldn’t identify; some element that wasn’t at all like a dog puppy.
“We’ll go in to meet the pups now,” Range said. The wolves would know if I was fearful, she added, and that would make them even more anxious, because they would not understand that I was afraid of them. “Just act normal,” she advised.
Virányi said, “Zip up your jacket. Make sure your shirt is tucked in. They may get attracted to anything that’s loose or hanging from your pockets. They would like to pull it.”
I nodded. It wasn’t hard to imagine why a wolf would like to pull something that was hanging from a body: What are those? Entrails? They were naturally curious, and a dangling shirttail would prove irresistible. Some years before, I’d met the wolves at another research facility, Wolf Park, in Battle Ground, Indiana. “Kneel down on their level to greet them,” the scientist there had instructed me. “They’ll want to welcome you to the pack. They’ll put their teeth on your head. It’ll be okay.” I knelt, and the wolves crowded in close, yipping with excitement, and brushing up against me. First one, then another, and finally a third took turns fastening their teeth lightly around the top of my head. From the corner of my eye, I could see that they needed to stand up briefly on two legs to do this. They opened their jaws wide to encompass my skull but didn’t bite; it was just a quick graze of fangs against skin. Perhaps because I’ve always loved dogs, I wasn’t frightened and didn’t pull away, but I’ve never forgotten the sensation, either.
Virányi unlocked the gate, and one by one we all went inside. She laughed and called to the wolves as if she were calling dog puppies. The wolves yipped and ran after her and Range, while Guinness and Tódor, who work with the wolves alongside the scientists, trotted close to their humans. The dogs held their heads up stiffly as if they were police dogs on assignment; they didn’t make any playful moves toward the pups. I followed, joining Virányi and Range beneath an apple tree. We sat cross-legged on the ground while dogs and wolves sorted out their own positions. Tódor, Virányi’s dog, took a seat square in the middle of her lap and barked sharply at the pups, while Guinness ran circles around us, keeping the pups corralled. The wolves had to wriggle and worm their way past Guinness to get to us.
“Do the pups think of the dogs as their elders?” I asked.
“Yes,” said Range. “Their mean elders. They let the pups know that they are dominant.”
“Actually, the dogs are a little bit afraid of the wolves,” Virányi said. “They were even afraid of them when the pups were just a few weeks old. They know that these are not dogs, even if they’re puppies.”
Two of the pups managed to crawl onto Range’s lap, while a third lay down next to Virányi. The scientists petted and fussed over them as one does with puppies. Tatonga, one of the gray-and-tan wolves, hesitantly approached me. She whimpered, wagged her tail, and inched closer when I spoke to her, imitating the way Virányi and Range talked to the pups, in a high, happy voice. “It’s okay. You can come close.” And she did, working up her courage to lick my hands and chin, and even giving me a gentle and friendly nip there. At last, somewhat relaxed, she tucked in her tail and placed her head in my lap so that I could stroke her. In time, all the pups came to greet me, licking and squirming around me as Tatonga did, and I petted them all. But I don’t want to give the wrong impression. I never felt that these wolf pups were completely at ease with me, or I with them. It wasn’t like sitting with a group of playful, loving dog puppies. Maybe the tension was partly due to Guinness and Tódor, who remained ever alert, lunging and barking sharply at the pups to keep them in line.
“That’s how the pups learn to behave,” Range said. “They’ve learned to pay attention to us and to follow some commands—to sit, lie down, stay—by watching the dogs. They do everything the dogs do”—which helped during the scientists’ behavioral experiments, when they asked the dogs to demonstrate what they wanted the wolves to do.
Virányi and Range were both in their thirties, and their style and personalities—Virányi, warm and outgoing, Range, more serious and cerebral—complemented each other. Their manner of relating to the wolves and dogs, on the other hand, was nearly identical: they were relaxed, patient, and affectionate—an ease that suggested they’d spent a good part of their lives in the company of animals, as was the case. Between them they had studied sooty mangabeys, capuchin and squirrel monkeys, marmosets, ravens, keas (a parrot species that lives in New Zealand), pigeons, gorillas, and orangutans. But dogs and wolves were now their passion. “It’s now my life’s work, forever, I think,” Virányi later told me.
Virányi had brought a long leash with her, and she clicked it onto Tatonga’s collar so that we could take the wolf for a walk and give her a social learning test. Every day, the wolf pups were led on these individual walks and given various tests to assess their skills as they grew up. From the center, we walked down a narrow lane to a meadow edged with conifers and oaks. Along the way, three students who worked at the center walked toward us; Tatonga knew them all, Virányi said, yet the pup tucked her tail between her legs and slowed her pace.
“Say something!” Range shouted to them. “Call to Tatonga!”
“Tatonga! Tatonga!” they shouted back. Tatonga pricked her ears forward, wagged her tail, and ran forward to greet them.
“She knows these girls very well,” Range said, as we continued on our walk. “You’d think she could just use her nose to smell them. We always hear so much about how dogs and wolves have such great noses. And then you see them do something like this. Sometimes even Guinness seems not to recognize me from a distance; then when I get close to her, or call her name, she acts exactly like Tatonga did, like she’s saying, ‘Oh, it’s you.’ Why doesn’t she just pick up my scent?”
The canine sense of smell was yet another example, Range said, of a trait we ascribe to dogs and wolves but about which we actually know very little. It was on the scientists’ lengthy list of canid abilities they wanted to investigate.
When we reached the meadow, Virányi first did a quick training session to teach Tatonga to look her in the eye, something that is difficult for wolves, as it is for most wild animals, because staring is generally a threat. She asked Tatonga to sit a few feet in front of her and held up a treat for her at arm level. Each time Tatonga met her gaze, Virányi snapped a clicker (a simple training device) while simultaneously tossing her the treat. Sometimes Tatonga looked straight at Virányi, other times she tilted her head from side to side, as if unsure where to focus. “She can only manage it for a second, or she’ll look at me from the corner of her eye,” Virányi said after the two-minute lesson. “The wolves know they must do something to get that treat, but they really aren’t sure what it is. They think maybe it’s about moving their head in a particular way, that’s why she does that funny head-wobble. And even when they figure it out, they can’t do it like a dog does, looking openly into your eyes. When I speak to Tódor, he turns instantly to focus on me, to gaze at my eyes. It’s like he’s asking, ‘What do you want to do?’ Or, ‘What do you want me for?’ Wolves don’t think that way; they’re too busy thinking for themselves.”
Next, the scientists gave Tatonga a social learning test that they give the wolves once a month. “We want to know at what age wolves can begin to learn something about their environment from humans, or from their conspecifics,” meaning their fellow wolves, Range explained. She emphasized that “nothing is known about social learning, or learning overall, in wolves; none of these tests [which comparative psychologists developed and use regularly with other animals from rats to pigeons] have been done before with wolves.”
The test was simple. First, away from Tatonga’s line of sight, Virányi walked on three different paths, each one the same length. When she returned, Range shortened Tatonga’s leash, while Virányi held the carcass of a baby chick just above her head, letting her sniff at it. The wolves are fed largely during their training exercises—“They must earn their food,” Range had said earlier—and Tatonga was hungry. She tried to leap at the chick, but Range restrained her from grabbing it. Virányi then turned and walked about twenty feet away along one of her original paths. At the end of this trail, she dropped the chick near some shrubs, and then, walking along the same path, returned to Tatonga. She showed her empty hands to the pup, turning them palm up for the pup to smell. Range kept her on the leash but let it play out so that Tatonga could go where she wanted. To my surprise, the wolf simply stayed put, never so much as taking a step on any of Virányi’s trails. Yet the pup had watched the human—who held the dead chick—walk to a very specific place. I thought about my own dog, Buck. Even as a four-month-old pup he would have figured out that I must have left the chick for him to find; he would have gone in search, and if he couldn’t find it on his own, he would have looked to me for help. Tatonga did none of these things. She sniffed the grass around her, gazed at the forest, and finally lay down. After two minutes, the test was over.
“Stupid, stupid, stupid wolf!” Range said, laughing, since nearly all the other wolf pups had easily passed the test. “You lost your chick.” In the wild, though, this type of failure would have serious consequences, since young wolves that did not pay attention to their caretakers’ or parents’ actions would likely not survive.
Tatonga didn’t seem to mind; it was as if she’d forgotten the bird entirely after Virányi displayed her empty hands. “The wolf puppies are really not like dog puppies; they don’t have that interest in everything we do,” Virányi said as we walked Tatonga back to the pups’ enclosure. “They are a lot more analytical and have some strong ideas, goals, and interests of their own. And they’re never really relaxed like a dog or a puppy. They’re almost overly sensitive; they jump away from you when you think that there’s no reason. And they’re always alert, just as you saw with Tatonga when we met the students. It’s as if they’re expecting danger, or that they’re more alert to the idea that things are uncertain.”
The first time Virányi raised a wolf pup, she was living at her parents’ home. Virányi arranged a sleeping area for herself and the pup in the living room, but the pup grew restless at night, and no matter what Virányi did to soothe her, she wanted to roam. “We put up a plywood board between the two rooms, and she got it in her mind that she wanted to get over it. She just would slam against it, for an hour at a time.” Then the pup would sleep for an hour, but as soon as she woke up, she started in again. “No matter how many times I corrected her, or told her no, or led her to another place with food rewards, she went right back to slamming against that board. She would just throw herself at it, over and over. Very different from a dog.”
As another example, Virányi described how differently the young wolves and dogs reacted when they first touched the electrical fence that surrounds the wolves’ enclosure. She had touched it herself to understand the buzzing sensation. “It didn’t really hurt, but it is a weird feeling.” When one young wolf received her first shock, she silently turned back to it and, from only an inch away, closely inspected the wire with her nose. “She seemed to know this thing caused the weird feeling.” In contrast, when Tódor was shocked, he ran screaming straight to Virányi and hid between her feet. “He growled in the direction of where this bad thing had happened, but he had no clue where the pain came from. If anything, he thought the people standing close to that spot had done it to him. Wolves,” she concluded, “seem to take many more things into account than do dogs.” For dogs, humans are “more important than anything else.”
Virányi and Range had tested the first three wolves they raised at the center for their ability to understand that they should go to the spot where a person points a finger. Another experiment had shown that both eight-week-old dog and wolf puppies can do this. Intriguingly, however, the four-month-old wolf pups in Virányi and Range’s test failed, as did four other wolf pups of the same age that were given the exam by other scientists at a wolf park in Hungary. “They were struggling and biting. They were just too busy doing other things to pay attention,” Range said. Only when they reach maturity (around two years old) are wolves able to pay sufficient attention to understand and follow a human’s pointing gesture. “They are on a different developmental path from dogs,” she said, perhaps because ultimately dogs “must live in our world and obey our rules. They have to learn many of the same things that children learn.”
In Budapest, when I’d been at the Family Dog Lab, I’d also met Márta Gácsi, one of the other researchers who’d helped with the lab’s wolf project and who’d led the study comparing wolves’ and dogs’ understanding of the human pointing gesture. She had shown me a video of a student trying to pet her seven-week-old wolf puppy while it was eating its dinner. As soon as her hand drifted toward the pup’s nose, the young wolf’s lips curled back, and he snapped viciously. “You know, sometimes you give a dog food, but sometimes you take it back,” Gácsi said, “and most dogs don’t mind. You can’t do that with a wolf, not even a pup. They really would bite, even though we had cared for them since they were just a few days old.” The differences in how dogs and wolves mature socially and developmentally are further evidence of the genetic changes that occurred in dogs as a result of being domesticated, Gácsi said.
When I mentioned Gácsi’s comment about the snapping wolf puppy, Virányi and Range smiled. They’d seen this behavior, too. Range said that people often asked her if she wouldn’t like to have one of the wolves live with her in her home. “I always say, ‘No,’ because I like to have access to my fridge. If a wolf is in my home, then he’s going to control the refrigerator”—and, I thought, everything else.
So given the headstrong, competitive, wary, and independent nature of wolves—even as pups—how had we ever domesticated them?e “I think probably some wolves came close to humans, maybe to scavenge,” Virányi said. “Maybe some stayed nearby, and they began to change, to become more relaxed. They had to because even in those days you could never have a wolf—a real wolf—in your home or camp. If you did, you’d have to watch your kids nonstop.”
Virányi said that probably some of the camp-following wolves had evolved to become somewhat friendly toward people. It was likely that it was their pups—pups that would have been easier to handle, and more willing to be looked at in the eye—that people first brought into their camps. “Then you could just start breeding—selecting—for these traits, for things you liked in the wolf. Actually, I have a harder time to imagine the people back then—what they were like, and how they knew to do this, to create the dog. When you think about it, it seems almost unreal, like a fantasy. How did they do it?”
IN FRANCE’S OLDEST DECORATED CAVE, the Grotte Chauvet, archaeologists have traced images of animals—lions, horses, rhinoceroses, and elephants—that the artists of twenty-six thousand years ago painted on the rock walls. They’ve found the skulls of cave bears and measured the tracks of cave bear paw prints. They’ve recorded the charcoal smudges left behind by people carrying torches to paint or perhaps to simply admire the great works of art. And in one chamber, they’ve found the footprint of a child. There are no other human footprints with this young person, who stood about four and a half feet tall, the scientists say. But there is another nearby footprint: a dog’s. Or a dog-wolf’s. They know the canid was more dog than wolf because of the length of its middle toe, which is doglike. The archaeologists investigating Grotte Chauvet cannot say for certain if the child and dog were together or if they came to the cave at separate times.
Most of us, though, would say the child and dog were surely there together and that they were friends, looking out for each other, so natural does it seem—even twenty-six thousand years ago—for humans and dogs to be a pair, working as a team.
* Researchers still don’t have an explanation for the difference between the sizes of dogs’ and wolves’ brains—or for why every species of domesticated animal, from ducks and geese to horses and pigs, also has a smaller brain than its wild ancestor. The reason or reasons domestication always leads to smaller brains are hotly debated; but the effects are universal. Anthropologists have documented the same change in Homo sapiens: the brains of modern humans have shrunk about 10 percent over the last ten thousand years.
† Another sign that animal cognition scientists have fully embraced dogs as a research subject comes from a simple count of the number of dog and canid papers presented at the Comparative Cognition Society’s annual international conference. In 1994, at the group’s first meeting, not one paper was about dogs. At their seventeenth meeting, in 2010, more than 10 percent of all the presentations were about dogs and their relatives. There has yet to be a similar boom in cat cognition studies.
‡ In 1994, Brian Hare, then an undergraduate at Emory University, stumbled into studying dog cognition after his mentor, Michael Tomasello, raised the question of whether chimpanzees understand what another chimp—or human—is thinking. Hare responded that he didn’t think the skill could be that difficult because, after all, “my dog does that.” Tomasello dared him to “prove it,” and the result was a study almost identical to that of the Hungarians on dogs’ abilities to understand the cues people give them by pointing or looking at something. Hare carried out his experiment with his family dogs in his parents’ garage. He is now a leading researcher in dog and primate cognition at Duke University.
§ There are differences between a dog’s and child’s responses to this test. If a different person moves the ball to Box B, the dog will follow his eyes and go to Box B. Switching adults doesn’t affect a child’s decision; he or she will still search for the ball at Box A, because toddlers are essentially programmed to receive instructions from all adults.
‖ Inspired by Rico, a retired psychologist in South Carolina, John W. Pilley, has taught his border collie, Chaser, 1,022 words. Chaser could have learned more, Pilley told a New York Times reporter in 2011, but the human was bored.
a I interviewed Kaminski and Betsy’s owners for my National Geographic article on animal minds; the owners were proud to have their dog featured, but they worried that someone who disliked dogs would recognize her from her photograph in the magazine and harm her.
b Kaminski now suspects that dogs “may perceive a lot of human communication as commands to do something.” Although we humans may tell our dog to “find the ball” or “find the Frisbee,” the dog may regard the name alone as an order. Thus a dog may think the sounds “ball” or “Frisbee” also mean “Find the ball” or “Fetch the Frisbee.”
c Studies comparing dog and wolf DNA indicate that dogs separated from wolves about one hundred thousand years ago, about the same time that our species, Homo sapiens, traveled from Africa into Southeast Asia and Europe. So it may be, as Csányi has suggested, that modern humans began domesticating the wolf not long after first meeting them. However, some archaeologists insist that these early wolf-dogs or incipient dogs were not dogs as we know them; they argue that truly domesticated dogs do not appear until much later in the archaeological record, when there is solid proof of the human-dog bond. For these scientists, the earliest domesticated dog dates only to fourteen thousand years ago—the date of a burial site in Germany where a dog and human were found interred together.
d Other researchers discovered that wolves need to be socialized very early in their development if they are to accept humans. Wolf pups that aren’t removed from their litters until they are eight to ten weeks old develop an extreme wariness of humans and try to avoid them.
e In the late 1950s, Dmitry Belyaev, a Russian geneticist, began a domestication experiment with silver foxes, selectively breeding them for the sole traits of friendliness to humans and reduced aggression. After more than forty generations, the foxes are very similar to dogs—they’re attracted to humans, they wag their tails and whimper when humans walk toward them, and they lick the humans’ hands. The foxes have also changed physically and now have black-and-white coats, floppy ears, and tails that curve over their backs; they also reach sexual maturity earlier, and they bark.