His last words ("You be good, I love you. See you tomorrow.") were the same words that he would say every night when Pepperberg left the lab. Criticisms Some academics are skeptical of Pepperberg's findings, asserting without data or peer-reviewed publication concerning Alex's data, that Alex's communications is operant conditioning. Nim Chimpsky, a chimpanzee, was thought to be using language, but there is some debate over whether he simply imitated his teacher. Herbert Terrace, who worked with Nim Chimpsky, says he thinks Alex performed by rote rather than by using language; without peer-reviewed publication he claims Alex's responses are "a complex discriminating performance", adding that he believes that in every situation, "there is an external stimulus that guides his response." See also References External links Alex Foundation Obituary article at the web-site of The Economist magazine New York Times obituary article The New York Times article "The Language of Birds" article includes a transcript and audio sample of Alex Audio of Australian radio interview with Irene Pepperberg Wired: Parrot Proves It's No Birdbrain Life with Alex: a memoir Film tribute to Alex. 1976 animal births 2007 animal deaths Animal intelligence Individual parrots Individual talking birds Psittacini Individual animals in the United States ceb:Alex, Haute-Savoie