In the course of scanning through Charles Darwin's 1871 book The Descent of Man to locate his Valentine-appropriate speculations on the origins of language in love songs, I was reminded of his brief remarks on talking parrots. This is a topic that came up recently due to the BBC wildlife piece on N'kisi (see here and here for discussion), and I should have thought to cite Darwin at the time. It's a bit depressing that so little has been learned about this over the past 134 years. In particular, it's surprising that we still know almost nothing about the role that complex vocalizations, imitative or otherwise, play in the normal life of parrots in the wild.
Here's what Darwin wrote, with a bit of the context from his Chapter III ("Comparison of the Mental Powers of Man and the Lower Animals"):
Posted by Mark Liberman at February 14, 2004 02:05 PMThat which distinguishes man from the lower animals is not the understanding of articulate sounds, for, as every one knows, dogs understand many words and sentences. In this respect they are at the same stage of development as infants, between the ages of ten and twelve months, who understand many words and short sentences, but cannot yet utter a single word. It is not the mere articulation which is our distinguishing character, for parrots and other birds possess this power. Nor is it the mere capacity of connecting definite sounds with definite ideas; for it is certain that some parrots, which have been taught to speak, connect unerringly words with things, and persons with events.*(2) The lower animals differ from man solely in his almost infinitely larger power of associating together the most diversified sounds and ideas; and this obviously depends on the high development of his mental powers.
*(2) I have received several detailed accounts to this effect. Admiral Sir. B. J. Sulivan, whom I know to be a careful observer, assures me that an African parrot, long kept in his father's house, invariably called certain persons of the household, as well as visitors, by their names. He said "good morning" to every one at breakfast, and "good night" to each as they left the room at night, and never reversed these salutations. To Sir B. J. Sulivan's father, he used to add to the " good morning" a short sentence, which was never once repeated after his father's death. He scolded violently a strange dog which came into the room through the open window; and he scolded another parrot (saying "you naughty polly") which had got out of its cage, and was eating apples on the kitchen table. See also, to the same effect, Houzeau on parrots, Facultes Mentales, tom. ii., p. 309. Dr. A. Moschkau informs me that he knew a starling which never made a mistake in saying in German " good morning" to persons arriving, and "good bye, old fellow," to those departing. I could add several other such cases.