A dog’s amazingly large vocabulary

A border collie named Rico recognizes a surprisingly large number of words.

Be careful what you say around your dog. It might understand more than you think.

A border collie named Rico recognizes the names of about 200 objects, say researchers in Germany. The dog also appears to learn words for new objects as easily as a 3-year-old child would. Its word-learning skill is as good as that of a parrot or chimpanzee.


A border collie named Rico knows the meaning of a surprisingly large number of words.


S. Baus

In one experiment, the researchers took all 200 items that Rico is supposed to know and divided them randomly into 20 sets of 10 objects each. The dog waited with one of his owners in one room, while an experimenter put a set of 10 objects into another room. Then, the owner told the dog to fetch one of the items. The dog had to go to the other room and bring the object back.

In four trials, Rico got 37 out of 40 commands right. Because the dog couldn’t see anyone to get visual clues about what to bring back, the scientists concluded that he must understand the meanings of certain words.

In another experiment, the scientists took one toy that Rico had never seen before and put it in a room with seven toys whose names he already knew. The dog’s owner then told him to fetch the object, using a word Rico had never heard.

In 7 out of 10 trials, Rico picked the right object, suggesting that he figured out the answer by process of elimination. A month later, he remembered half of the new names, which further impressed the researchers.

Rico is probably smarter than the average dog, the scientists say. For one thing, he’s a border collie, a breed known for its mental abilities. In addition, the 9-year-old dog has been trained to retrieve toys by their names since he was 9 months old.

It’s hard to know if all dogs understand at least some of the words we say. Even if they do, they can’t talk back. Still, it wouldn’t hurt to sweet-talk your pup every now and then. You might just get a big, wet kiss in return!


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