New research suggests economic growth is behind the extinction of most languages and revealed global "hotspots" of language extinction in which "immediate attention" must be focused.
Some of these threatened areas included north Australia and the north-western corners of the U.S. and Canada; the tropics and Himalayan region are also undergoing rapid economic growth, putting them at a higher risk of language extinction, the University of Cambridge reported.
To make their findings the research team used criteria for defining endangered species to measure the "rate and prevalence" of language loss.
The team found the three primary risk factors were "small population size (small number of speakers), small geographical habitat range and population change - in this case, the decline in speaker numbers."
By looking at huge datasets the team found levels of GDP (Gross Domestic Product) per capita was linked with a decline in language diversity. They found the most successful the economy the more quickly language diversity was lost.
"As economies develop, one language often comes to dominate a nation's political and educational spheres. People are forced to adopt the dominant language or risked being left out in the cold - economically and politically," said Tatsuya Amato, from the University of Cambridge's Department of Zoology. "Of course everyone has the right to choose the language they speak, but preserving dying language is important to maintaining human cultural diversity in an increasingly [globalized] world."
In the northwest corner of the U.S. the languages of indigenous people are rapidly vanishing. Upper Tanana, a language spoken by the Athabaskan people in eastern Alaska had only 24 active speakers as of 2009, and is no longer being taught to children. As of 2008 the Wichita language of the Plains Indians had only one fluent speaker. In Australia aboriginal languages are also taking a hard hit.
"Languages are now rapidly being lost at a rate of extinction exceeding the well-known catastrophic loss of biodiversity," the researchers said.
The researchers believe language diversity could potentially be saved by bilingualism; past research suggest children who speak multiple languages have a number of cognitive and social advantages.
"As economies develop, there is increasing advantage in learning international languages such as English, but people can still speak their historically traditional languages. Encouraging those bilingualisms will be critical to preserving linguistic diversity," Amano said.
The findings were published in the journal Proceedings of Royal Society B.
