The power of speech -Patrick Barkham

Daniel Everett looks and talks very much like the middle-aged American academic he is - until he drops a strange word into the conversation. An exceptionally melodic noise tumbles from his mouth. It doesn't sound like speaking at all. Apart from his ex-wife and two ageing missionaries, Everett is the only person in the world beyond the sweeping banks of the Maici river in the Amazon basin who can speak Pirahã.

Just 350 Pirahã (pronounced Pee-da-HAN) hunt and gather from their simple homes in the Brazilian rainforest. Linguists believe their language is unrelated to any other; racist Brazilian traders say the Pirahã talk like chickens. This obscure Amazonian people speak using only three vowels and eight consonants (including the glottal stop) but their language is far from simple. Like Chinese, for example, Pirahã is tonal and speaking in a different pitch transforms the meaning of a word. Unlike other tonal languages, Pirahã can also be hummed and sung. The Pirahã have no socially lubricating "hello" and "thank you" and "sorry". They have no words for colours, no words for numbers and no way of expressing any history beyond that experienced in their lifetimes. And, in the late 70s, Everett was dispatched to the Amazon to learn their language, translate the Bible and convert them to Christianity.

'It's wrong to try and convert tribal societies' ... Everett with a

member of the Piraha. Photograph: Martin Schoeller