Chaser

Chaser has a way with words. She knows over a thousand of them-more than any other animal of any species except humans. In addition to common nouns like house, ball, and tree, she has memorised the names of more than one thousand toys and can retrieve any of them on command. Based on that learning, she and her owner and trainer, retired psychologist John Pilley, have moved on to further impressive feats, demonstrating her ability to understand sentences with multiple elements of grammar and to learn new behaviours by imitation. John's ingenuity and tenacity as a researcher are as impressive as Chaser's accomplishments. His groundbreaking approach has opened the door to a new understanding of animal intelligence, one that requires us to reconsider what actually goes on in a dog's mind.