Chaser_Unlocking the Genius of the Dog Who Knows a Thousand Words

by John W. Pilley

  It was all music to my ears. So was the brief article, more or less a capsule version of what was in the New Scientist, from the BBC’s website.

  While Sally and I read the articles, Debbie and Jay called back several times to report the growing number of Google and YouTube hits.

  “It’s like a pop song going number one with a bullet,” Debbie said, as the hits for the YouTube video climbed from forty to more than a hundred thousand in a few hours’ time.

  Chaser caught the current of excitement in Sally’s and my voices and body language, and she continued to want to play with her ball and other toys. Normally this was a quiet time, with me heading off to bed and Chaser settling down by Sally while she watched a television show or read a book before coming to bed herself. Sally and I happily indulged Chaser that night.

  Debbie and Jay read a number of the YouTube viewers’ comments to Sally and me on the phone. It was fascinating to hear how people were engaging with each other about Chaser and sharing stories about their own dogs. Quite a few viewers were debating the extent to which dogs could learn elements of human language, but always in a spirit of admiration for dogs’ intelligence and problem-solving abilities. As a group the people commenting on Chaser’s video repeatedly expressed an abiding love of dogs, gave thanks for the love dogs expressed in return, and stated the belief that their own dogs understood much of what was said to them.

  The comments brought the same feelings to the surface in Sally and me. When we finally turned out the lights and wished each other and Chaser good night, we were aglow with gratitude and joy for our good fortune. I went to sleep thinking that Chaser’s story could only have spread so far, so fast, because of the loving relationships that people experience with their dogs.

  The next month was a whirlwind. The New Scientist article triggered interest in our work, and the BBC article sent Chaser’s story racing around the globe. My contact information was on the Behavioural Processes paper, and every day my e-mail inbox teemed with fresh requests for media interviews and appearances. The phone started ringing on Christmas Day and didn’t stop for weeks.

  Chaser was the feel-good story of the holidays. When the holidays ended, the phone calls and e-mails didn’t let up. Alliston and I were lucky that Wofford College’s director of news services, Laura Corbin, took on the main burden of prioritizing media requests and scheduling interviews. Without her expert help, our heads would never have stopped spinning as we tried to sort things out. Or to borrow another analogy from Debbie, trying to keep up with the requests for interviews and information on Chaser was like trying to hit back balls from a hundred tennis machines at once, all of them set on rapid fire. As it was, Alliston and I each fielded hundreds of calls and did dozens of radio interviews. Alliston also did interviews in his fluent Spanish for media in Mexico and Spain. In late January, Laura Corbin tallied coverage for Chaser in more than forty-six languages around the world.

  Deb was waiting in line at the supermarket one evening when she spotted the gossip tabloid the National Examiner and did a double take. Chaser was on the cover alongside Charlie Sheen and Brad Pitt. The copy next to Chaser’s picture said, “DOG-GONE SMART! The world’s brainiest pooch.” Deb grabbed a copy to buy, telling the cashier, “I don’t normally read this, but that’s my dad’s dog on the cover.” With an I’ve-heard-that-one-before tone the cashier said, “Uh huh” and continued ringing up Deb’s purchases.

  In typical tabloid fashion the National Examiner had to knock someone, even in the canine world. The story said Rico only knew “a piddling” two hundred words and that “Chaser makes Rico look like a howling idiot.” I found this upsetting, but Deb quickly put it into perspective for me: “You didn’t say it, Dad. It’s a tabloid and that’s what they do—they slam people. It’s hysterical that Chaser is on the cover with Brad Pitt.”

  Among the first journalists to call me for an interview was Annette Witheridge, the British correspondent in New York City for the Daily Mail, Britain’s second-biggest newspaper. She asked if she could come to Spartanburg to see Chaser demonstrate her learning, and in the middle of the week between Christmas and New Year’s, she arrived on our doorstep with the photographer Chris Bott. On January 1, 2011, the Daily Mail and the paper’s website ran Annette’s article, “Who’s a VERY Clever Doggy! Prepare to Be Bow-Wowed as We Put Chaser, the World’s Brainiest Dog, to the Test.”

  In a very down-to-earth way, Annette’s article captured much of what I felt was important about Chaser’s story, beginning with the fact that Chaser is a beloved member of the Pilley family and not simply a research subject. Annette really caught Chaser’s personality, describing “her tail wagging so hard that half her body seems to be joining in” and evoking her social nature: “‘Ooh, a new playmate; ooh, a new playmate,’ she seems to be saying.”

  Annette’s very personal response to meeting Chaser came to typify for me how people opened their hearts to Chaser and related her learning to memories of their own dogs. After asking me several questions, Annette shared her memories of Trixie, the collie mix her family had when she was a child. She proudly relayed that when anyone spelled W-A-L-K, Trixie knew what they meant. Hearing that made Sally giggle and she walked into the living room to say, “Chaser’s exactly the same. When I say I’m off to pick up the M-A-I-L, she shoots out the door.”

  Perfectly on cue, Chaser sprang to her feet and went to the door, ready to help fetch the mail from our street-side mailbox. That’s one of her important jobs, by the way. She insists on carrying a piece of mail into the house. It’s the same when Sally comes home from the grocery store. Chaser insists on carrying something from the car to the kitchen. Once I gave her a banana to carry, which she did without leaving a mark on it. Since then I’ve been saying that we should try her out with an egg, but Sally says that’s not practical and that Chaser’s feelings would be hurt if she cracked the egg in her mouth and thought she’d let us down. Either that, or we’d need to buy a lot more eggs.

  Alliston came over to participate in the interview, and Annette asked him to relate Chaser’s abilities to the way children learn language. Alliston told her, “A child of two understands the phrase ‘I love you.’ I don’t think Chaser would know that. By three, a child would say: ‘Mummy, I love you’ and know the meaning. Chaser couldn’t do that.”

  I saw a small smile on Annette’s face as Alliston said this, as if she felt sure Chaser knew the meaning of “I love you.” In her story she quoted Alliston’s remark, and then added, “As if to prove otherwise, Chaser . . . wags her tail and looks at me as if to say: ‘Yes, I could.’ And based on what I’ve seen today, I wouldn’t put it past her.”

  The volume of e-mails and phone calls about Chaser increased even more after this piece appeared. One day Sally took a call from someone in Los Angeles who wanted Chaser to appear on a show there. We had decided that we weren’t going to fly Chaser anywhere, because we didn’t want her to have to travel apart from us in a plane’s cargo hold. I heard Sally explain that, and focused my attention on answering some of the e-mail about the paper. Half an hour or so later I came downstairs for a drink of water, thankful that I hadn’t heard the phone ringing and hoping things were starting to calm down. The calls had been coming in nonstop.

  However, Sally was still chatting with the same person. It was a few more minutes before she hung up the phone and said, “What a nice young man.” She was about to elaborate when the phone rang again.

  It was Debbie, and Sally and I both got on the line. Deb had been trying to reach us and asked if the phone had been off the hook. Sally explained that she’d been talking to someone who wanted Chaser and me to appear on his television show in Los Angeles. Sally was getting frustrated with all the phone calls about Chaser, although she was always gracious when she answered the phone.

  Sally said, “I explained that it was too much travel and we wouldn’t put Chaser in a plane’s cargo hold. Most people hang up when I say that, but he kept asking questions about Cha
ser and talking about his own dog. He really loves dogs. Finally after forty-five minutes I told him I needed to go.”

  Deb asked, “Did you get his name?”

  Sally said, “It was Jimmy something.”

  “Jimmy Kimmel?”

  “That’s it! How did you know?”

  Deb sighed and said, “Just a guess.”

  We especially enjoyed the visit to Spartanburg of a reporter and a photographer from the French magazine Paris Match. Having spent her junior year of college in Aix-en-Provence and being fluent in French, Robin was able to explain that Paris Match is like a combination of People and Time magazines. The reporter, Olivier O’Mahony, was as struck by Chaser’s social nature as Annette Witheridge had been. His story described how Chaser brought him a ball as soon as she saw him and called her “the most sociable dog” he’d ever met: “In five seconds, I have made a new friend. In the world of humans, this takes more time.”

  After Chaser brought her ball over to make friends, I told her Olivier’s name by pointing to him and saying, “Chaser, this is Olivier.” As usual in such circumstances, just as when I show Chaser a new toy, she was lying on the floor and apparently looking the other way. Although I explained to Olivier that Chaser was giving me her ear and giving him a glance of her eye, he obviously had his doubts. So I asked him to go hide in the other room, and then said, “Chaser, find Olivier.” He was astonished and delighted when she immediately went and nosed him out of his hiding place behind the couch.

  Meanwhile, Sebastien Micke, Olivier’s photographer colleague, was out in the yard in the snow, creating a display of Chaser’s toys. Sebastien’s pursuit of the perfect shot knew no bounds, and he lay full length in the snow to get it (see photo insert).

  When the story on Chaser ran in the January 20–26, 2011, issue of Paris Match, it immediately followed one on John Travolta and his family. That tickled all of us, and Debbie said Chaser was now indisputably an A-list celebrity.

  It was a very different situation when Nicholas Wade, the chief science editor for the New York Times, contacted Alliston and me. Like Jessica Griggs for the New Scientist, Nicholas Wade was all about the science. Many of his questions had to do with whether Chaser’s results in various trials really avoided the Clever Hans effect, and he paid particular attention to the video, part of the online backup to the Behavioural Processes paper, that showed Chaser in a take-nose-paw test.

  We video- and audio-recorded the test at Wofford College. The setup had me kneeling behind a screen that was thirty-nine inches high by four and a half feet wide. On a cloth in front of the screen were three of Chaser’s toys: Lips, which is shaped like a pair of human lips; ABC, a cloth cube with those letters on its sides; and Lamb, a stuffed toy resembling a lamb. These were the objects I would ask Chaser to take in her mouth, nose, or paw. Sally sat at the side of the room more than fourteen feet away from the screen and just slightly behind me. Her job was to wave her hand when she saw Chaser take, nose, or paw an object. When Sally waved her hand, I said, “Good dog!” Sally then put the objects back in place in front of the screen while I rewarded Chaser with brief play with a ball, before we conducted another trial.

  I had assigned a different number to each of the three objects and three commands, and used a random number table to pair commands and objects for fourteen trials. During each trial I couldn’t see what Chaser was doing, and Chaser couldn’t see me. Sally could see when Chaser did something with an object, but she was too far away to tell which object Chaser took, nosed, or pawed, or to cue Chaser’s choices.

  Afterward, three Wofford students independently watched the video with the sound turned off and wrote down Chaser’s actions in all fourteen trials. Then they each independently watched the video with the sound turned on and assessed whether Chaser’s actions matched my instructions. The raters unanimously agreed that Chaser got everything right.

  Nicholas Wade interviewed Alliston and me separately about the video. His questions indicated that he had scrutinized it frame by frame, and that he had also discussed it and everything else in the paper with outside experts.

  On the night of Monday, January 17, 2011, Nicholas Wade’s article, “Sit. Stay. Parse. Good Girl!: Dog Might Provide Clues on How Language Is Acquired,” appeared on the New York Times website. On Tuesday morning it was the lead story in the paper’s weekly “Science Times” section.

  The article gave a very thorough account of the Behavioural Processes paper and Chaser’s language learning to that point in time. The opening paragraph put as big a smile on my face as the one in the New Scientist. It said:

  Chaser, a Border collie who lives in Spartanburg, S.C., has the largest vocabulary of any known dog. She knows 1,022 nouns, a record that displays unexpected depths of the canine mind and may help explain how children acquire language.

  Wade discussed how the high working drive of Border collies helped explain why Chaser “proved to be a diligent student,” and he compared Chaser’s learning to Rico’s. He drew out the implications of Chaser’s abilities for understanding both nonhuman animal intelligence and children’s language learning, “because children could be building on the same neural mechanisms.” And he devoted six whole paragraphs to the danger of the Clever Hans effect and the safeguards against it in Chaser’s language trials.

  “Haunting almost every interaction between people and animals is the ghost of Clever Hans,” Wade wrote. He quoted Alexandra Horowitz, scientist-author of Inside of a Dog, on Border collies’ sensitivity to people’s voices and attention cues as a possible source of Clever Hans effects. But he also noted that she said “the experimental design [in the Behavioural Processes paper] looks pretty good.” Wade revealed that Horowitz had been one of the expert reviewers on the paper I submitted to Science, and I breathed another sigh of relief that this flawed first attempt to publish my findings with Chaser had been rejected.

  Wade emphasized that Chaser’s language trials followed the same rigorous procedures as in the Rico study at the Max Planck Institute for Evolutionary Anthropology in Germany. He quoted Juliane Kaminski, the lead author of that study, as saying, “I think the methodology the authors use here is absolutely sufficient to control for Clever Hans.”

  The specter of Clever Hans is one of the biggest thorns in the side of any researcher who wants to demonstrate learning by nonhuman animals. Although Jessica Griggs had referred to Clever Hans obliquely, her article did not mention his name or go into any detail. I was grateful to Wade for highlighting the most critical area that had to be controlled in my experiments with Chaser and my procedures for doing so.

  I regularly taught my students about the horse Clever Hans. Owned by a high school math teacher named Wilhelm von Osten in early-twentieth-century Germany, Clever Hans could apparently understand spoken and written German, identify musical pitches, interpret clocks and calendars, and do arithmetic with both whole numbers and fractions. Hans amazed large crowds free of charge by counting off correct answers in sequences of numbers and letters with hoof taps.

  In 1904, the German government’s so-called Hans Commission decided that no deception was involved. But in 1907, the psychologist Oskar Pfungst showed that Hans was responding to the increase and release of tension in von Osten’s posture and body language. When Hans saw von Osten tense up in anticipation of his answer, he started tapping his hoof. When he saw von Osten relax, he stopped tapping.

  Von Osten had no idea he was cuing Hans, and Pfungst found that he himself and other questioners also produced involuntary cues in working with Hans. If questioners knew the answer, then Hans read their body language and almost always “answered” correctly. If questioners thought they knew the answers but were supplied with false information, then Hans again read their body language and “correctly” answered according to the questioners’ false beliefs. But if the questioners simply did not know the answers, Hans only got an answer right now and then by pure chance.

  The Clever Hans effect, as this involuntary cu
ing became known, is so pervasive and powerful that drug and bomb detection dogs may produce false positives in response to their handlers’ body language. With their acute sensitivity to human body language, the dogs see that someone or something has aroused their handlers’ suspicions and they react accordingly.

  It’s not hard to produce a Clever Hans effect intentionally, either. I described earlier how Robin did that in teaching Yasha to “count.” From the start of my research with Chaser, I knew that other scientists would not accept my results unless I controlled absolutely for Clever Hans effects. In their paper in Science, the Rico researchers made a major point of their avoiding Clever Hans effects. In his critique of the Rico study, the Yale psychologist Paul Bloom stressed the importance of their doing so successfully. And it was inevitable that peer reviewers would train a laser eye on whether I fell victim to the Clever Hans effect.

  The need to avoid Clever Hans effects was not a stumbling block. It was a given of animal learning research that I had taken account of throughout my research in graduate school and at Wofford. I was glad to demonstrate in a crystal-clear manner that Chaser performed language tasks without any visual cues.

  At the end of his article Wade came around, like the New Scientist and BBC articles, to how intensive training might explain Chaser’s unprecedented results. Had I “lucked out in finding an Einstein of the [dog] species,” or was I right in suggesting to him that “most Border collies, with special training, ‘could be pretty close to where Chaser is’”? He gave the final word to Alexandra Horowitz, writing, “Dr. Horowitz agreed: ‘It is not necessarily Chaser or Rico who is exceptional; it is the attention that is lavished on them,’ she said.”

  Readers were quick to comment on the story on the New York Times website. After approximately 360 posts, comments were no longer being accepted. Scrolling through the posts on the site, I saw the same mix as for the YouTube videos of Chaser. There were some skeptics, but the overwhelming tone of the comments was one of celebration. It was wonderful to see people’s enthusiasm for understanding their dogs better and enriching their relationships with them.