Einstein is an African Grey parrot who can imitate a spaceship, a laser, and a chimp at will, besides uttering sage words of wisdom upon receiving a cue (and a peanut) from her trainer, Stephanie White. Einstein has a working vocabulary of over 200 words, an impressive number, but nowhere near the upper limit of the range of language that birds have been shown to learn and use.
Three classes of birds – parrots, songbirds and hummingbirds have been shown to have the ability to mimic human speech. Since birds lack vocal cords, the sounds we hear are produced by vibrations of their throat muscles and membranes – you could call it a form of whistling. Vocal mimicry requires significant learning and cognitive capacities in these birds, and involves advanced and specialized brain regions. So, why do they do it?