Whistled

As communication

On La Gomera, one of Spain's Canary Islands, a traditional whistled language, Silbo Gomero, is still used. At least nine separate whistling sounds are used to produce usually four vowels and five consonants. The language allowed people (such as shepherds) to communicate over long distances on the island, when other communication means were not available. It is now taught in school so that it is not lost among the younger generation. Another group of whistlers were the Mazateco Indians of Oaxaca, Mexico. Their whistling aided in conveying messages over far distances but was used also in close quarters as a unique form of communication with a variety of tones.