ABSTRACT
An African Grey parrot has been taught to use the sounds of English speech to identify, request, refuse, categorize, and quantify more than 80 different objects and to respond to questions concerning categorical concepts of color and shape. The parrot, Alex, has now been trained and tested on relational concepts of same and different. He learned to reply with the correct English categorical label (“color”, “shape”, or “mah-mah” [matter]) when asked “What’s same?” or “What’s different?” about pairs of objects that varied with respect to any combination of attributes. He performed equally well on pairs of novel and familiar objects, and special trials demonstrated that his responses were based upon the question being posed as well as the attributes of the objects. These results are compared with the findings of other studies on animal cognition and interspecies communication.
