COMPREHENDING CANINE Border collie Rico has a 200 (human) word vocabulary. If asked to retrieve a toy with a name he has never heard, Rico will pick out a new toy from a group of familiar items (Kaminski et al., 2004). Hearing that name for the second time four weeks later, Rico more often than not retrieves the same toy. Another border collie, Chaser, has set an animal record by learning 1022 object names (Pilley & Reid, 2011). Like a 3-year-old child, she can also categorize them by function and shape. She can “fetch a ball” or “fetch a doll.”

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