Facebook, YouTube and even texting will be the salvation of many of the world's endangered languages, scientists believe.

Of the 7,000 or so languages spoken on Earth today, about half are expected to be extinct by the century's end.

Globalisation is usually blamed, but some elements of the "modern world", especially digital technology, are pushing back against the tide.

North American tribes use social media to re-engage their young, for example.

Tuvan, an indigenous tongue spoken by nomadic peoples in Siberia and Mongolia, even has an iPhone app to teach the pronunciation of words to new students....