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Chaser the Border Collie learned 1,000 words - could my dog learn that many words, too?

In 2004, Science published an article about a dog named Rico who learned over 200 words by just everyday play with his owners. In response, John Pilley with Wofford College in Spartansburg, South Carolina acquired Chaser the Border Collie, and the dog who would eventually learn 1,000 words. Chaser also demonstrated the ability to fast-map or pairing new words with new objects by inferential reasoning. Chaser’s ability to understand words parallels that of a human toddler! But, do all dogs have this ability? Until more research is collected using more dogs of different breeds and backgrounds, we cannot yet say that all dogs can use language to this degree. Either way, Chaser is amazing! Follow her page @chaserthebordercollie on Instagram. Read on to learn more about Chaser, and find out whether your dog can do this, too!


Human beings are thought to be the most sentient, most creative, and most intelligent beings on this earth. But is that really true? What really makes us unique? Many suggest that the ability to communicate and use language in the way that humans do is what makes us truly amazing. However, researchers since the 60s have been discovering word-learning abilities in primates, grey parrots, and even dolphins, but it wasn’t until 2004 that dogs took center stage as another animal that may share certain language-like abilities with human beings.

An article published in Science described a 9-year old Border Collie named Rico who had acquired the knowledge of over 200 words for toys when playing with his owner. Rico was also tested in the lab and was able to use exclusion learning – or understanding an object a new amidst many known objects to quickly learn referential language. This exclusion learning ability is often called fast-mapping in human toddlers and is what allows them to learn language so quickly, and without specifically being told the names of everything they learn.

To better understand this phenomenon, researchers acquired Chaser – a pet Border Collie that would be immersed in human word-object pairings in hopes of replicating what occurred with Rico. What they found is truly amazing. Over the course of 3-years of daily, immersive training, Chaser was able to learn the names of 1022 toys! Not only did Chaser develop an expansive vocabulary, she could understand that certain words were for objects, while others were for commands. She would correctly respond to commands such as “Paw Lamb” or “Take ABC”, referring to separate actions and objects. Chaser could also understand more common nouns, for example that “ball” referred to more than one object, and actually referred to a whole group of different balls! Finally, Chaser again demonstrated the ability to learn objects by exclusion, or fast-map. This may all seem a little bit familiar, because Chaser did appear on television shows, and her owner, John Pilley, wrote a book about her exceptional receptive language skills. Find his book here

Like I said before – this is all truly amazing. Chaser might just be the smartest dog in the world! But are all dogs that way? Can your dog learn 1,000 words, too? We don’t quite know yet, but preliminary results in my own research suggest that Chaser’s exceptional ability might be unique to dogs like her, but not all dogs. For thousands of years, humans have domesticated dogs for very specific purposes. A dog’s “family history” could give them a big genetic advantage in terms of receptive language learning tasks. For example, Border Collies like Chaser are herding dogs, bred for their ability to take direction from their handlers when sheep herding. Great Pyrenees were also bred to work with Shepherds, but in a much different way – they were bred to stand atop the mountain and watch for predators that might harm the sheep. Herding dogs like Collies would work directly with their handler, taking commands and direction, while the Pyranees would work as guardians, making independent decisions. While many dogs of these breeds no longer work in the field they are bred for, these inbred tendencies can still cause changes in behavior, and possibly, cognitive ability.


Sources: & Pilley, J. W., Reid, A. K. (2011). Border collie comprehends object names as verbal referents. Behavioural Processes, 86, 184-195. doi:10.1016/j.beproc.2010.11.007

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