A border collie with a stellar vocabulary has accomplished a type of learning previously only seen in toddlers. The researchers say the finding indicates that even mammals distantly related to humans may have the rudiments of language learning.
Word learning starts with understanding the relationship between a word and the object it stands for. Children learn words by show-and-tell, or infer them by the process of elimination. For example, if a child is told to fetch a fruit with an unfamiliar name from a bowl containing well-known apples and bananas plus a novel object, chances are he or she will figure out that the novel fruit corresponds to the new word and will remember that in the future. This kind of learning is called fast mapping, and until now it has only been demonstrated in children. But animal communication specialists at the Max Plank Institute for Evolutionary Anthropology in Germany now report that fast mapping is also at work in an ambitious border collie named Rico. Their work appears in the 11 June issue of Science.
Rico made a splash on German TV in the 1990s when he appeared on a game show demonstrating his talent for words. The 10-year-old dog can understand more than 200, mostly names of toys, and retrieve those objects on command. Julia Fischer and her colleagues designed a series of experiments for Rico, first verifying his vocabulary in a controlled environment, then testing his fast-mapping skills by asking him to fetch something he'd never heard of nor seen from amongst a pile of familiar toys. Seven times out of 10, Rico got it right. And Rico remembered about half of the objects a month later, with no further training. Fischer says Rico's performance supports the notion that the beginnings of humans' language skills can be seen in other animals, and it's consistent with the hypothesis that listening evolved before speaking in the animal kingdom.
The study is valuable because it shows that dogs are useful subjects for comparative cognitive psychology, says Paul Bloom, a psychologist at Yale University. However, he is skeptical about what it says about language development. "When a child learns a word, he learns that it refers to a category of things." The child can eventually form sentences to express ideas about the word. It's unclear if Rico is learning words in this sense, or simply learning one-word commands, says Bloom.
Paul Bloom's lab
University of Pennsylvania language and communication primate research
Primate Cognitive Neuroscience Laboratory at Harvard University
Max Planck Institute for Evolutionary Anthropology