Cats rule, dogs drool, right? Not this time. It looks like the dogs have won this round thanks to a border collie named Chaser, who has the largest vocabulary seen in any animal.
Alliston Reid and John Pilley, psychologists at
Wofford College in Spartanburg, South Carolina, have been working with Chaser to see if there is a limit to the number of words a border collie can learn. So far, Chaser knows 1,022 words.
While Chaser has the broadest vocabulary in animal history, she isn't the first to border collie to be trained to learn the English language. Rico, a border collie who was trained at the
Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, knew a total of 200 words. In addition, Rico was capable of using the process of elimination to distinguish new objects within a group of familiar objects.
But Chaser has surpassed Rico by leaps and bounds. Not only does Chaser know 822 more words than Rico, but she can also categorize words of items according to shape and function. According to the study, this is something human children learn around the age of three.
Reid and Pilley taught Chaser to recognize the names of 1,022 toys over a three year period. Toys were presented to Chaser individually, and the name of the toy would be repeated in order to help Chaser
learn to recognize it.
To make sure Chaser was actually learning the names of these toys, she was tested on a regular basis. Tests consisted of researchers choosing 20 toys at random, and allowing Chaser to retrieve them when the toy's name was called. The toys were put in an entirely different room so that researchers could not "unintentionally give Chaser cues about which toy to choose."
Out of a total of 838 tests over a three year time span, researchers reported that Chaser chose at least 18 out of 20 correct toys when the toy's name was called.
"The experimenters did a lot of controls to exclude alternative explanations, although from my experience the results are simply too good," said Dr. Adam Miklósi, founder of the
Family Dog Project at Eötvös Loránd University in Budapest, Hungary.
In addition to learning 1,022 words, Chaser was also taught to categorize objects by touching groups of related toys with her paws or nose. She could also point out the name of a new object within a group of familiar objects.
"This study shows that this dog has good skills for comprehension but the production side of communication is missing," said Miklósi.
What Miklósi means is that other animals have been able to vocalize words in addition to just recognizing them.
