How to Tame a Fox (and Build a Dog)

by Lee Alan Dugatkin

  By sunset they had collected samples from about 100 foxes. The next day, they did the same again. “Lyudmila brought a cake to the farm for the animal keepers,” Anna says, “to thank them at least a little bit for all the extra work that they did for us.”

  Anna didn’t have the necessary permits for bringing blood samples into the US from overseas because she had not expected to get them on this trip. Fortunately, she didn’t actually need the blood per se, just the genetic material in it. So when she stopped in St. Petersburg on the trip back to Cornell, she turned again to her friends at the university and they agreed to extract the DNA from the samples even though they had only five days before she flew home. Her friends rallied and they finished the job in just three. They understood how important the analysis of the DNA might be.

  The drive to isolate genes linked to fox domestication was on.

  9

  Clever as a Fox

  The opportunity to collaborate on studies with the domesticated foxes was of great interest not only to geneticists like Anna Kukekova, but to specialists in animal behavior as well. Just as Aubrey Manning was captivated by the early reports in Western scientific journals about the experiment when organizing his 1971 Ethology meeting in Edinburgh, in the 1990s a new generation of animal behavior researchers recognized how valuable the fox findings were to their work, and how important new studies conducted with the foxes could be. An explosion of new work was focusing on animals’ cognitive abilities and the kinds of learning they are capable of. The foxes presented a golden opportunity for exploring differences in cognition between domesticated animals of a species and their wild relatives.

  Lyudmila and Dmitri had agreed that the genetic changes leading to the foxes’ domestication must have primed their brains for learning how to be more sociable with people. Pushinka had learned to show Lyudmila special loyalty, and she also believed Pushinka had likely demonstrated rudimentary reasoning ability. And Pushinka’s clever deception in playing dead in order to catch the crow seemed to show strategic forethought. But Lyudmila did not have any expertise in studying animal cognition, and had not launched any studies to test the foxes’ thinking skills.

  Getting inside of an animal’s mind is tricky. Any dog owner who has watched a dog gingerly grasp a rawhide bone in its mouth and proceed to a corner of the room, or behind a chair, pawing at the floor and then gently placing the bone down as if burying it has wondered what exactly is going on in his pet’s brain. Is his little terrier or beagle playacting? Is he or she engaging in the equivalent of a child’s imagined tea party or fire truck rescue? Or has the dog perhaps learned, smartly, that stowing the bone away for lean times ahead might be a good idea? When cats pounce at one another from behind a door are they creating scenes in their minds of masterful hunting feats, and are they envisioning themselves eluding a fearsome predator as they race through a room? Maybe instead, our pets are simply acting on instinct, as Charles Darwin surmised about the dog he observed turn round and round on a carpet thirteen times before settling down for sleep.

  What exactly is the nature of animals’ mental lives? We don’t really know. The most difficult questions to answer about animal behavior have been those about the nature of animal minds and emotion. Darwin had conjectured that animal cognition and emotion are on a continuum with that of humans. But as researchers made more discoveries during the twentieth century about how genetically programmed animal behavior can be—such as Konrad Lorenz’s demonstration that Greylag goslings would mistake a rubber ball for their mother during the imprinting period—they were extremely careful not to anthropomorphize and project human-like thoughts onto animals. Jane Goodall’s assertions about chimpanzees had kicked up such a storm over inferences about animals’ inner lives that the bar of proof was now set very high. But Goodall’s observations, along with the observations of other animal behaviorists, had also stirred up interest in finding new ways to probe into the nature of the animal mind.

  Many ethologists who undertook this work, such as Bernd Heinrich and Gavin Hunt, followed in the tradition of Lyudmila’s mentor Leonid Krushinksy, as well as Nobel Prize winner Nikolaas Tinbergen, studying animals in the wild. A number of fascinating studies revealed that animals besides primates make use of tools. The crows of New Caledonia (Corvus moneduloides) are master toolmakers in the avian world.1 These birds extract insects from under tree bark using tools they construct from twigs and leaves. They thrust the tools into cracks in the bark, and when the target insects react defensively and grab the tool, the birds pull the tools back and either gobble up the bugs or feed them to hungry offspring. They learn to make these tools during the first year or two of life, as they progress from apprentices, watching skilled toolmakers tinkering with their creations, to master toolmakers themselves. They begin by making the simplest tools, which are twigs that they strip leaves and side bits from, so they’re nice and smooth for probing. Eventually they figure out how to fashion more complex tools, such as twigs with hooks at the end. To do this, they select a small branch that is forked into two slender branches, and they bite one of the branches off right above the base of the fork, so that the remaining branch now has a small “v” at the end, as when the wishbone of a chicken is snapped and one side is much shorter than the other. They then do a kind of whittling of the v with their bills to sharpen it.

  These crows make tools from the barbed edges of leaves of the screw pine, tapering the leaves toward the end, akin to the tip of a spear, and then using these as probes to poke about for food. Researchers who have studied these birds in the lab discovered that they would also use novel objects like cardboard and aluminum to fashion tools, which led researchers to install a series of “crow cams” in their natural habitat in New Caledonia to see if they display such ingenuity in the wild. This produced footage of the birds sculpting molted feathers and dry grass into tools as well. The footage also showed that, on occasion, the birds even use their tools to get at lizards, an especially juicy and protein-rich treat. Remarkably, they also safeguard their best and favorite tools for reuse.2

  Why New Caledonian crows show this dramatic tool-making expertise and other species do not is a subject of much discussion. Researchers have searched for what factors are operating in crows, but absent in other bird species that don’t make tools, to find an answer. The working hypothesis is that a combination of conditions facilitated their development of this ability. Low competition from other birds for food and low predation rates are thought to have afforded them more time to experiment with tools, and the relatively long developmental period of these crows offers youngsters ample opportunity to learn the skills from their parents and other adults.

  In addition to the studies on animal learning per se, a good deal of work has focused on their memory abilities, and some astonishing findings have been made. In the animal world, few can match jays, a member of the corvid family that includes ravens and crows, for feats of memory. While some jay species don’t store much food for times of trouble, other species can remember the location of 6,000 to 11,000 seeds that they have stored over the course of nine months. This ability is linked to the very large size of the hippocampal area of their brains.3 Western scrub jays take bird smarts up a notch. They not only recall where they have stored vast numbers of food items, but they remember who was watching them when they cached their food, and when they are watched will later dig up and hide the food elsewhere, presumably to protect their stored food from being stolen.4

  Some species may have a rudimentary ability to understand numerosity. Chimps can recognize that there are more yummy pieces of sweet banana on one plate than another. Dogs accustomed to receiving a certain number of treats will make clear they expect the usual number if shorted. They will also be noticeably disturbed if treats are distributed inequitably to them and another dog gets more. Desert ants, who have few cues from their barren environment to help them find their way back home, can gauge how many steps they have taken from their nests on foraging jou
rneys. Collecting a sample of ants that had gone out on a foraging party, animal behaviorists worked out a way to attach tiny stilts to the ants’ legs, which made their legs 50% longer. Returning them to the foraging grounds and observing them make their way back to their nest, the researchers found that the ants walked 50% farther than they should have, at which point they stopped and began searching for their nest. They had overshot it by just the distance that the extra length of their strides accounted for, which can most reasonably be explained by them having kept track of how many steps they had taken.5

  During this boom of research, the study of reasoning ability also advanced considerably. A number of researchers began asserting anew that some nonhuman animals demonstrate reasoning skills. The strongest claims were made, of course, for primates. The notion that primates have human-like reasoning ability actually went back to the early twentieth century. German researcher Wolfgang Kohler observed apes while he was head of the Prussian Academy of Sciences primate research station in the Canary Islands in the 1910s, and he wrote about how creative they were in solving many problems. He had watched them put wooden crates one on top of the other in order to climb up on them to reach bunches of bananas, and also use long sticks to whack them down from trees. He described these feats in an influential book, The Mentality of Apes, first published in Germany in 1917, in which he argued that the apes had clearly applied reasoning skills to accomplish them. His work had fallen out of favor in subsequent decades as so much work focused on conditioning and instinct alone in explaining animal behavior. But the observations of Jane Goodall, Diane Fossey, and others of chimps and gorillas, followed up by a new generation of primatologists, including Frans de Waal, Dorothy Cheney, Robert Seyfarth, and Barbara Smuts, who made observations of the complex social lives of bonobos and other primates in the wild and in the laboratory, brought it back into vogue.

  One particularly fruitful vein of research in this area has been the study of animals’ social cognition, meaning their ability to evaluate the social situation they are in, such as with chimpanzees foraging in a group in the forest, or a group of dogs let out to play in a dog run. Researchers study how animals respond to cues from one another, or respond to cues from other animals, such as the way dogs are so adept at reading their owner’s moods. This was the area of work to which the tame foxes were to make a major contribution.

  One of the leading contributors to this research on animal social cognition traveled to Akademgorodok to conduct an intriguing study with the foxes. Brian Hare was still working on getting his PhD at the time, under the supervision of Richard Wrangham, with whom he went on to write the papers about self-domestication in bonobos. Brian’s specialty was in comparing social cognition abilities across animal species, and he was focusing on studying dogs and primates. He was particularly interested in understanding how their social skills had evolved.6

  There was no question from Brian’s own work, and the work of others, that non-human primates, like chimpanzees and baboons, showed sophisticated types of social cognition. This was seen, for example, in the way primates groom one another.7 Researchers sweating in the sweltering heat of Africa, waiting for a chimp or gorilla to do something astonishing that no one else has ever observed, have learned the hard way that instead many primates will spend endless hours doing nothing but sitting and grooming one another in what looks like an almost meditative trance. The primary purpose of grooming is to get rid of parasites that are in hard to reach places, but it also seems to reduce tension within groups, lowering levels of stress hormones in the recipient, and increasing the circulation of pleasurable chemicals, such as endorphins, in both parties. In some cases, strict social rules of reciprocity seem to govern these grooming rituals. After all, grooming someone takes time, and in a competitive biological marketplace like nature, rather than time being money, it’s the currency of survival. It must be doled out with great care. Engaging in any activity that you don’t get paid back for sufficiently is risky business, and primates are able to keep close track of their accounts. When Gabriele Schino looked at social grooming in thirty-six studies done in primates, she found individuals were keeping close track of who groomed them, and dispensing grooming as a function of that. Indeed, sometimes they even paid back being groomed in a different currency, such as help finding food or water. You need to know who you can trust in the world of grooming, and animals are acutely aware of their social milieu when they jump into this business.8

  Other work has revealed that some primates follow social rules governing the formation of coalitions and alliances to get what they want. Baboons have developed a “buddy” system, according to which individuals keep track of who can be trusted and who can’t.9 During mating time, male baboons low on the dominance totem pole will often solicit the aid of another male to gain access to a receptive female that is being guarded by a more dominant male. Craig Packer observed that one baboon will often recruit another to join him in threatening an opponent by repeatedly looking over at the recruit while he continues to make threatening gestures toward the opponent. Sometimes this works, and when it does, the male who did the recruiting is rewarded by being able to mate with the opponent’s female mate. The male who joined this alliance gets something in return; those who help are much more likely to get help in return with their own such challenges.10

  Social cognition in the animal world can also involve deception. In vervet monkeys, when a predator is spotted, individuals emit alarm calls to warn others and some vervets have found a way to use these calls to fool the others in the group and save their own skins. When vervet troops meet along their borders, aggression sometimes breaks out between members of these groups. In 264 intergroup interactions that Dorothy Cheney and Robert Seyfarth recorded, false alarm calls—calls when there is no real danger—were sometimes made by low-ranking males. They seemed to be diverting attention to a mythical predator so that the group focused on that threat rather than on engaging in conflict among themselves, in which these low-ranking males would likely take the worst beating.11

  Animals clearly understand more about their social milieu than researchers originally thought. Brian Hare had contributed important findings about animal social cognition through his studies on dogs and primates. Research had shown that on one classic social intelligence test—what is known as the object choice test—chimps came up short versus dogs, who performed brilliantly on it.12 Researchers had found that if they placed two opaque containers on a table, and then, unknown to the chimp, put food under one, it was very difficult to provide a chimp with a visual cue that it could use to figure out where the food was. You could point at the correct container, stare at it, touch it, or even place a marker like a wooden block on it, and chimps just don’t get it: they are no more likely to choose the container with food than the one without it. Dogs, on the other hand, are virtual geniuses at this sort of object choice task, and are able to cue in on what chimps seem oblivious to.13

  Hare had conducted his own studies comparing the ability of chimps and dogs and confirmed just how much smarter dogs were at this task. Then he asked himself: Why are dogs so good at this? Maybe it was because dogs spend their whole lives with humans, and learn how to do this sort of thing. Or it could be that all canids—dogs, wolves, and so on—were just good at object choice tests, and that it had nothing to do with “dogginess” per se. The only way to know was to design an experiment, so Brian tested both wolves and dogs on this task. The dogs shined as always, and the wolves seemed clueless as to what was going on.14 Not all canids could do this. He also tested dog pups of different ages. They all did just fine on the object choice test. He tested dogs who had lots of interactions with humans versus few interactions. They all did fine as well. So, Hare realized, it wasn’t the amount of time with humans that made dogs so good at the task.

  The obvious conclusion was that dogs seemed to have an innate talent for it. That answers the question at one level, but not another. Why, Brian wondered, do dogs have th
is innate ability to solve hard social cognition tasks whereas chimps don’t? The answer, he surmised, likely had something to do with the fact that dogs had been domesticated. “It is likely,” Hare wrote in his 2002 Science paper, “that individual dogs that were able to use social cues more flexibly than could their last common wolf ancestor . . . were at a selective advantage.”15 During the process of domestication, dogs that were smart enough to pick up on social cues emitted by their humans would get more food because they could do the things that humans wanted them to do, so humans might toss them more scraps as a reward. They might also be able to pick up on cues humans didn’t necessarily want them to pick up on, and occasionally scarf some food not meant for them.

  It made perfect sense. The skill in dogs was a beautiful adaptation to their new life situation, selected for by their new human masters. He’d come up with a tidy and beautiful explanation for an important question: just the sort of thing a young scientist dreams of.16

  His mentor, Wrangham, thought otherwise about Hare’s findings. Yes, he told Brian, picking up the skill must have something to do with domestication, but was his adaptationist tale—that animals that were socially smarter were selected by humans—the only possible explanation? Was it necessarily the case that the amazing ability of dogs to pick up on human social cues had been favored by selection? Wrangham thought not. He proposed an alternative hypothesis. Maybe, just maybe, this ability was just an accidental byproduct of domestication.17 Picking up on human social cues hadn’t been selected for, he proposed, it just came along for the ride with other traits that had been selected. Hare decided to take the challenge of testing their competing ideas, and they placed a little wager on who was right.

  There was really only one place where Hare could do this test, and that was at the fox farm in Akademgorodok. It was the only place where animals had been domesticated from scratch, and where researchers know exactly what sort of selection pressures had been in place, and that selection for social intelligence, per se, had not been applied. If Brian was right, both the domesticated foxes and the control foxes should fare poorly on the social intelligence test, because the fox team had never selected foxes based on their social intelligence per se. If Richard was right, and social intelligence was indeed a byproduct of domestication, then the domesticated foxes should show social intelligence on par with dogs, but the control foxes should not. When he contacted Lyudmila, through one of her colleagues, to ask whether she would approve of his conducting the study, she said she would love for him to do so. After scraping together about $10,000 in funding from the Explorers’ Club, Hare was off to Akademgorodok. Lyudmila and the Institute research staff and fox farm workers gave him a warm reception, and he was thrilled at how quickly he was accepted into their close-knit circle. He even enjoyed the common mispronunciation of his name among the researchers, as “Brain.”