Scholastic opinion varies on the percentage to which body language is part of human communication. But verbal communication needn't be the only alternative. Fascinatingly, there are still places where people are actually not lost without words.
On La Gomera, in the Canary Islands, there is a language called silbo Gomero that uses a variety of whistles instead of words (in Spanish silbar means "to whistle"). There are four "vowels" and four "consonants" that can be strung together to form more than four thousand "words". It can be heard at distances of up to two miles and silbadors were until recently a dying breed. Since 1999, however, silbo has been a required language in La Gomera schools.
Other whistling communicators include the Mazateco Indians of Oaxaca, Mexico. Their whistling is not really a language or even a code; it simply uses the rhythms and pitch of ordinary speech without the words.
Similar languages are found in Greece, Turkey, and China, while other forms of wordless communication include the talking drums (ntumpane) of the Kele in Congo, the xylophones used by the Northern Chin of Burma, and the banging on the roots of trees practised by the Melanesians.
Elsewhere, there are kinds of speech sound that do not use an air stream from the lungs. Native speakers of Xhosa, one of the official Bantu languages of South Africa, use words that contain click consonants.
Two countries, Papua New Guinea (with more than 850) and Indonesia (with around 67), are home to a quarter of the world's spoken languages because the terrain can be so rough that language and communication are often keenly affected. This sense of the intransigible has brought about a vocabulary of its own. Krosa is Sanskrit for a cry, and thus has come to mean the distance over which a man's call can be heard: roughly two miles. In Sri Lanka's central forests, calculations of distance are also made by sound: a dog's bark indicates a quarter of a mile; a cock's crow something more; and so on. In the Yakut language of Siberia, kiosses represents a specific distance calculated in terms of the time taken to cook a piece of meat. My favourite is the Finnish word poronkusema – the distance equal to how far a reindeer can travel without a comfort break. It's about three miles and literally means "reindeer's piss".
Adam Jacot de Boinod is the author of The Meaning of Tingo and Other Extraordinary Words from around the World (Penguin), and creator of the iPhone App Tingo, a quiz on interesting words