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Chaser the Dog: Incredible Facts About the World’s Smartest Pup

Oliver Jones

By Oliver Jones

Blue Merle Border Collie laying on the grass

Chaser the Dog was a female Border Collie that earned the title of the world’s smartest pup. Her dedicated owner trained her to learn a wide range of words along with simple sentences using children’s toys to test the limits of her intelligence.

When you read about Chaser, it’s obvious that her limits were boundless, and her legacy lives on today. In honor of this smart pup, we have compiled a list of incredible facts about Chaser, the world’s most intelligent pup. Let’s have a look!

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The 11 Facts About Chaser the Dog

1. Chaser Has the Largest Tested Vocabulary of Any Animal in the World

The world’s largest animal vocabulary belongs to Chaser. She was given this distinction because she could combine words into straightforward sentences and comprehend that each word had a distinct meaning. Her formal language learning even surpasses that of primates and dolphins.

We know that she earned the title of the world’s smartest dog. However, all dogs have unique talents, and Chaser’s incredible achievements highlight how dogs are much more intelligent than we give them credit for!

2. Chaser Was Taught Words Using Toys and “Errorless Learning”

Chaser’s owner, Dr. Pilley, started training Chaser when she was 2 months old. The training started with a blue ball using “errorless learning.” Errorless learning is a teaching method that assumes dogs do not need to learn by making mistakes and eventually correcting them. Dr. Pilley would show the blue ball to Chaser, say the command “catch blue,” and throw the ball to her.

He would also place it in front of her and say the cue “find blue.” He realized it was time to switch to a new object on the third day when she could fetch the ball from a different room. She had mastered 40 words by the end of the 5th month and retained them in her memory long-term.

3. Chaser Learned to Identify More Than 1,000 Words in Her Lifetime

Throughout Chaser’s life, her owner trained her every day to learn and recognize the name of her toys. She eventually demonstrated that she could comprehend over 1,000 different words.

Chaser started to learn concepts and began to learn by inference. She realized that when her owner said, “This is,” he would name something. She had 30 balls which she knew by proper noun and category, as well as by adjectives such as smaller and bigger.’

4. Chaser Understood that the Commands and Proper-Noun Names Had Independent Meanings

By randomly combining nouns with commands, Chaser was tested to see if she would exhibit the correct behavior toward the right object. Chaser responded correctly to each combination, indicating that she truly comprehended that the proper nouns and commands had independent meanings.

Chaser understood that names correspond to certain things, regardless of the desire for an action involving those things.

5. Chaser Was Not an Obedient Dog

A dog with the title of most intelligent pup in the world will naturally have you believing they are obedient; however, Chaser was not an obedient dog. She knew the obedience commands, but her owner only utilized them for safety. Their relationship emphasized actual teamwork rather than obedience.

6. Chaser Is the Most Scientifically Important Dog in Over a Century

Chaser consistently astounded the world with her knowledge, whether by impressing astrophysicist Neil deGrasse Tyson or Anderson Cooper on “60 Minutes.” She was even asked to appear on the TV program “Scorpion,” and she was highlighted in several important publications.

Brian Hare, co-author of The Genius of Dogs, said, “Chaser is the most scientifically important dog in over a century. Her fascinating story reveals how sophisticated a dog’s mind can be.”

7. Chaser Knew the Difference Between Her Toys and Other Objects

Chaser was so smart that she could differentiate between her toys and other objects. This meant there was no chance of chewing up a toy or shoe that did not belong to her.

8. Chaser’s Learning Was Considered Limitless

Chasers’ owner stopped at 1,022 objects because he thought it was enough, and his wife Sally didn’t want more toys in the house. Every day, Chaser continued to learn new words, and if her owner hadn’t reached an advanced age, she might have learned many more. The extent of her cognitive capacities was never even approached, and Chaser was capable of limitless learning.

9. Chaser Loved Children

Some dogs have an unconditional love for children, and Chaser was no exception. She loved kids because they made the best playmates, and she loved her toys! Just like small children, dogs have so many opportunities to learn through play, so having children that are present and willing to play with a dog is ideal.

10. Chaser Did Not Bark Until She Was 6 Years Old

Dogs, especially puppies, are generally known to be yappers, and although all dogs bark to some extent, Chaser didn’t really bark until she was 6 years old. Her bark was loud and deep, and because she didn’t bark often, her owners made sure to listen when she did.

11. Chaser’s Legacy Lives On

Chaser passed when she was 15 years old, but although she is longer here, her legacy lives on. In the spring of 2020, the Children’s Museum got a bronze monument of Chaser from the Spartanburg organization Hub City Animal Project.

Her owner also wrote and published a book titled “Chaser: Unlocking the Genius of the Dog Who Knows a Thousand Words.” Chaser’s book is a top seller on Amazon and a New York Times best seller.


The Man Behind the Dog

Chaser’s owner and trainer was a psychologist named Dr John W. Pilley. Many dog owners struggle to teach their dogs simple commands, but Dr. Pilley trained his Border Collie to grasp more than 1,000 words.

Sally, Dr. Pilley’s wife, gave him a black-and-white Border collie, which he named Chaser. Dr. Pilley spent 4 to 5 hours a day, for 3 years, training Chaser. He would show her something, repeat its name up to 40 times, hide it, and then ask her to retrieve it. He eventually taught Chaser 1,022 nouns using 116 balls, 800 cloth animal toys, 26 Frisbees, and various plastic objects.

Dr. Pilley’s research, which demonstrated how Chaser was taught to comprehend phrases with a prepositional object, verb, and direct object, was published in 2013. He is renowned as a scientist for his fundamental and ground-breaking studies on canine cognition, which provided factual support for the idea that dogs are far more intellectually adept than previously believed.

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Final Thoughts

Chaser was dubbed the most intelligent pup in the world, but her accomplishments prove that dogs are more intelligent than we may care to believe. She understood common nouns and proper nouns and knew that words have independent meanings. Her owner and trainer, Dr. Pilley, told the New York Times in 2014 that “the big lesson is to recognize that dogs are smarter than we think, and given time, patience, and enough enjoyable reinforcement, we can teach them just about anything.”

Featured Image Credit: Dora Zett, Shutterstock

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