Go Fetch

From an early age, humans learn words and their associations. For example, infants know that forks are related to plates because both are used to eat. 

Now, a new study found that dogs are also capable of categorizing objects by function, rather than just by similar appearance. This skill is known as “label extension.” 

“We discovered that these Gifted Word Learner (GWL) dogs can extend labels to items that have the same function or that are used in the same way,” study author Claudia Fugazza said in a statement, adding that it’s similar to a person calling both a traditional hammer and a rock with the same name. 

“The rock and the hammer look physically different, but they can be used for the same function,” she said. “So now it turns out that these dogs can do the same.”  

Through playful interactions at home with their owners, a group of GWL dogs with no prior training learned two verbal labels, namely “Pull” and “Fetch.” The labels were applied to different types of toys they played with based on how the toys were used, rather than how they looked.  

For example, if a toy was tugged, it was labeled as a Pull type, while if it was retrieved, it was a Fetch type. 

The dogs showed they were capable of distinguishing between toys used for tugging versus fetching when their name – Pull or Fetch – was spoken, even when those toys did not have any obvious physical similarities. 

The seven dogs in the group – six border collies and one blue heeler – were also able to remember those categorizations for long periods of time. 

Then, new toys were added to the collection of the two distinct categories. While they were still played with by being tugged or retrieved, the “Pull” and “Fetch” labels were not spoken during the play session.  

Researchers found that the dogs had learned to extend the functional labels they had learned previously to the new toys based on their experience in playing with them. When asked to bring a Pull or Fetch toy from the pile, the dogs chose the correct new toys more often than chance alone would allow. 

“For these new toys, they’ve never heard the name, but they have played either pull or fetch, and so the dog has to choose which toy was used to play which game,” said Fugazza. “This was done in a natural setup, with no extensive training. It’s just owners playing for a week with the toys. So, it’s a natural type of interaction.”   

The dogs’ ability to connect verbal labels to objects based on their functions, and apart from the toys’ physical appearance, indicates that they form a mental representation of the objects based on their experience with their functions, which they then remember, the team noted. 

According to researchers, the study results provide insight into the evolution of basic language-related skills and their relationship to other cognitive abilities, including memory.