Interspecies Communication with Grey Parrots: A Tool for Examining Cognitive Processing

  • Irene M. Pepperberg


For over 35 years, I have examined Grey parrot cognition via a modeling technique, whereby birds are trained to use elements of English speech referentially, so they can be questioned vocally, much like young children. The oldest bird, Alex, labeled >50 objects, seven colors, five shapes, quantities to eight, three categories (color, shape, material) and used “no,” “come here,” “wanna go X,” and “want Y” (X, Y being appropriate location or item labels) intentionally. He combined labels to identify, request, comment on, or refuse >150 items and to alter his environment. He understood concepts of category, relative size, quantity, presence or absence of similarity/difference in attributes, showed label comprehension and a zero-like concept; he demonstrated some understanding of phonological awareness and a numerical competence more like that of young children than other nonhumans. He could be queried about optical illusions in ways directly comparable to humans. Younger birds are acquiring similar competence.


Phonological Awareness Regular Polygon Subjective Contour Arabic Numeral Young Bird 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Department of PsychologyHarvard UniversityCambridgeUSA

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