Animals, A Dog and Its Extensive Human Vocabulary

One dog exhibits a facility with human words

Dogs may be able to understand far more words than a typical owner teaches them during obedience training.

• Scientists experimenting with a nine-and-a half-year-old border collie in Germany have discovered that the dog knows more than 200 words (in German, yet) for different objects and can learn a new word after being shown an unfamiliar item just once.
• The dog's ability shows that advanced word recognition skills are present in animals other than humans, and no doubt evolved independently of language and speech.
• Rico, the border collie, was taught to find and return different objects by his owners, who placed various balls and toys around their apartment and asked Rico to fetch specific ones. Rico gradually increased his vocabulary to about 200 words that he could match with objects.
• To make sure Rico's owners weren't in some way giving him cues that helped him find the right item, Julia Fischer and her colleagues at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, tested Rico's knowledge in a lab, where he retrieved 37 out of 40 items correctly.
• "Rico's 'vocabulary size' is comparable to that of language-trained apes, dolphins, sea lions, and parrots," the authors wrote in their report, published in the June 11, 2004, issue of Science magazine.
• The team then tested Rico's ability to employ fast mapping, a neurological process that toddlers use to quickly guess the meaning of new words.
• The researchers put an unfamiliar object in a room with other things he did know and, without teaching Rico the name of the specific item, asked him to get it.
• Seven times out of 10 he returned with the correct object.
• Four weeks later, the scientists tested Rico's ability to recall what he had learned.
• The objects that he had seen only once during the previous experiment were placed among eight other things, some familiar and some completely new.
• In this trial, Rico retrieved the correct item three out of six times, a feat of learning never before seen in a dog.
• Rico's performance was comparable to that of a three-year-old toddler, the scientists observe.
• Fischer and her collaborators explained that they're not sure whether Rico is exceptionally smart or exceptionally well trained, but they hope they can use this experiment to further probe how the brain learns to understand words.
• Rico's powers of comprehension, they say, show that the processes the brain uses to discern words are not the same as those used to produce speech.
• Says Fischer: "You don't have to be able to talk to understand a lot."