AFTER A LONG DAY of being a dog, no dog in existence has ever curled up on a comfy couch to settle in with a good book. Dogs just don’t roll like that. But that shouldn’t imply that human words don’t or can’t have meaning for dogs.

Chaser, a Border Collie from South Carolina, first entered the news in 2011 when a Behavioral Processes paper reported she had learned and retained the distinct names of over 1,000 objects. But that’s not all. When tested on the ability to associate a novel word with an unfamiliar item, she could do that, too. She also learned that different objects fell into different categories: certain things are general “toys,” while others are the more specific “Frisbees” and, of course, there are many, many exciting “balls.” She differentiates between object labels and action commands, interpreting “fetch sock” as two separate words, not as the single phrase “fetchsock.”

Fast forward two years. Chaser and her owner and trainer Dr. John Pilley, an emeritus professor of psychology at Wofford College, appeared again in a scientific journal. This time, the study highlighted Chaser’s attention to the syntactical relationships between words, for example, differentiating “to ball take Frisbee” from “to Frisbee take ball.”