The finding of a parrot with an almost unparalleled power to communicate with people has brought scientists up short.
The bird, a captive African grey called N'kisi, has a vocabulary of 950 words, and shows signs of a sense of humour.
He invents his own words and phrases if he is confronted with novel ideas with which his existing repertoire cannot cope - just as a human child would do.
N'kisi's remarkable abilities feature in the latest BBC Wildlife Magazine.
N'kisi is believed to be one of the most advanced users of human language in the animal world.
About 100 words are needed for half of all reading in English, so if N'kisi could read he would be able to cope with a wide range of material.
Parrot uses 950 words to talk with people, crack jokes
By Bill Peña on 02/14/2007