This chapter briefly reviews what is known—and what remains to be understood—about Grey parrot vocal learning. I review Greys’ physical capacities—issues of auditory perception and production—then discuss how these capacities are used in vocal learning and can be recruited for referential communication with humans. I discuss cross-species comparisons where applicable and conclude with a description of recent research that integrates issues of reference, production and perception.
Pepperberg, I. M. (2010). Vocal learning in Grey parrots: A brief review of perception, production, and cross-species comparisons. Brain and language, 115(1), 81-91.