One of the dogs mentioned in the Nat Geo article was Rico. His abilities have been demonstrated and analyzed in a number of forums, including prestigious scientific journals (here is one article). By following German or English commands to fetch objects, Rico showed that he knew over 200 object names. When asked to fetch a new object with an unfamiliar name, he would use a process of elimination, or "fast mapping," to correctly choose the new object from among others that he had already learned. This is similar to the cognitive process that underlies the rapid vocabulary growth in human toddlers at 2-3 years of age. And after only one trial of fetching an unfamiliar object and learning it's name, Rico could recall the new object/name association four weeks later.
Rico the Bilingual Border Collie
If you could speak what would you say
Would you tell us to stop making you fetch stuff
Or would you say that it's okay
Canine Social Cognition – What Do We Know?
22 hours ago