Rico, The Dog Who Understands Words

Wouldn’t it be nice to talk to our dogs and know that they understood every word we say? I talk to my dog all the time, and I have some limited proof that he understands some of what I am saying to him. When I say, “Where’s your ball?’ he goes and gets his ball, when I say “Do you want to go outside/” he runs to the front door, and when I say, “Are you hungry?” he wags his tail vigorously and runs around in circles. However, all of that doesn’t have to mean that he understands what I am saying. It could merely be operant conditioning at work. He might have learned to associate a particular set of sounds with a response that results in a reward.

Now we have Rico, a 9-year-old border collie (at the time) who was tested by rigorous experiments and found to understand the meanings of about 200 different words. In a report in the journal Science (J. Kaminski, J. Call, J. Fischer, 2004, Word learning in a domestic dog: Evidence for “fast mapping,” Science 304: 1682-1683), Rico was tested for his ability to retrieve objects that he had never seen before. The experimenters took some pains to make sure that there was no subtle cueing going on. In one experiment, Rico and his person waited in another room while the experimenters arranged at random some of the 200 objects whose names he knew, in groups of 10 objects per time. Then Rico was asked by his person to bring two of the objects, that neither he nor his person could see directly. Rico successfully brought 37 out of 40 objects that were requested. In another experiment, a novel item, that Rico had not seen before or knew the word for, was placed with 7 objects that Rico knew, and his person asked him to bring the novel object, saying the word for the object. Out of 10 such sessions, Rico was successful 7 times. Finally, four weeks after he was exposed to the words for the novel objects, he was asked to retrieve one of those objects from a group of 4 familiar objects, 4 objects that he had never seen before, and the novel object that he was asked to retrieve a month before. Rico brought back the correct object 3 out of 6 times, a rate that the experimenters say compares well with how humans remember the names of objects.

So it seems that Rico actually knows the words that stand for specific objects. As one commentator has pointed out (P. Bloom, 2004, Can a dog learn a word?, Science 304: 1605-1606), Rico knows only 200 words, while a 9-year-old child knows thousands of words. However, let’s just assume, for the sake of argument, that dogs have a language that they use to communicate with other dogs. Then we can ask: Just how many words of dog language do WE know?

--Con Slobodchikoff

Comments

[Randall Johnson]

What useful purpose--scientific or otherwise-- is served by trying to compare the vocabulary of a 9-year-old child with that of a 9-year-old dog as if they were on equal linguistic footing? A 9-year-old human would be reasonably expected to have a vocabulary of thousands of words in his or her native language, but until Rico came along, no one really expected a dog to be capable of learning the meanings of 200 words, which, by the way, is close to the accomplishments of the late Washoe, whose vocabulary was around 250 words in American Sign Language. Canine cognition studies have shown that dogs understand the concept of object permanence, are capable of selective imitation, know what pointing and glancing mean in terms of information cues, among other things. It seems to me that Rico’s achievements have unveiled another exciting potential worth exploring and I, for one, would like to see this experiment replicated in other households with different breeds.