Grey parrots (Psittacus erithacus) solve various cognitive tasks and acquire and use English speech in ways that often resemble those of very young children. Given that the psittacine brain is organized very differently from that of mammals, these results have intriguing implications for the study and evolution of vocal learning, communication, and cognition.
Pepperberg, I. M. (2002). Cognitive and communicative abilities of grey parrots. Current Directions in Psychological Science, 11(3), 83-87.