Image copyright Thinkstock Image caption The better the economy, the more likely a national language will dominate 
 
 Economic development is driving the extinction of some languages, scientists believe. 
 
 A study has found that minority languages in the most developed parts of the world, including North America, Europe and Australia, are most at threat. 
 
 The research is published in the Proceedings of the Royal Society B. 
 
 The researchers say that efforts to protect these languages need to be focused on these areas. 
 
 Lead author Tatsuya Amano, from the University of Cambridge, said: "World languages are now rapidly being lost. This is a very serious situation. 
 
 "We wanted to know how the extinction is distributed globally and what are the main drivers of this." 
 
 Vanishing voices 
 
 Dr Amano, who usually looks at extinction rates in animals, said that about 25% of languages around the world were under threat. 
 
 People are forced to adopt the dominant language or risk being left out in the cold - economically and politically Tatsuya Amano, University of Cambridge 
 
 The researchers found that the more successful a country was economically, the more rapidly its languages were being lost. 
 
 They said that in North America, languages such as Upper Tanana, were now spoken by fewer than 25 people in Alaska, and were at risk of vanishing forever. 
 
 In Europe, languages such as Ume Sami in Scandinavia or Auvergnat in France are fading fast. 
 
 Dr Amano said: "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 risk being left out in the cold - economically and politically." 
 
 The team also found that languages in the Himalayas are at risk, such as Bahing in Nepal, which has an estimated eight speakers. In the tropics, too, voices are disappearing. 
 
 "These countries are experiencing rapid economic growth, so in the near future these languages will face risk of extinction." 
 
 The scientists call for conservation efforts to focus on these regions. 
 
 Dr Amano said that work undertaken to protect languages such as Welsh in the UK was a good example a successful strategy. 
 
 Commenting on the research Daniel Kaufman, executive director of the Endangered Language Alliance, said: "Environmental factors have been overshadowed by social, political and economic factors. 
 
 "We are now seeing a pattern of linguistic diversity that was originally shaped by the environment give way to a pattern that is being shaped by policy and economic realities. 
 
 "The environmental pattern at this point is largely historical residue. That is, we will no longer see areas of a particular environmental type attract or spawn language diversity. The economic aspect, however, cannot be overemphasized, as there are places within the language diversity 'hotspots' where whole villages are being emptied out due to out-migration. 
 
 "Because much of this migration is recent and undocumented, accurate numbers are unfortunately not readily available for statistical analysis." 
 
 Follow Rebecca on Twitter ||||| The world's roughly 7000 known languages are disappearing faster than species, with a different tongue dying approximately every 2 weeks. Now, by borrowing methods used in ecology to track endangered species, researchers have identified the primary threat to linguistic diversity: economic development. Though such growth has been shown to wipe out language in the past on a case-by-case basis, this is the first study to demonstrate that it is a global phenomenon, researchers say. 
 
 Many people know about the threatened polar bear and extinct passenger pigeon, but few have heard of endangered and extinct languages such as Eyak in Alaska, whose last speaker died in 2008, or Ubykh in Turkey, whose last fluent speaker died in 1992, says Tatsuya Amano, a zoologist at the University of Cambridge in the United Kingdom and lead author of the new study. It’s well known that economic growth or the desire to achieve it can drive language loss, he notes—dominant languages such as Mandarin Chinese and English are often required for upward mobility in education and business, and economic assistance often encourages recipients to speak dominant languages. Whereas specific case studies demonstrate such forces at work, such as the transition from Cornish to English in the United Kingdom and from Horom to English in Nigeria, this is the first study to examine losses worldwide and rank economic growth alongside other possible influences, he says. 
 
 Data on the number and location of surviving fluent speakers of endangered languages are scant, but Amano and colleagues used the most complete source available—an online repository called Ethnologue—for their analysis, he says. From the database, the group was able to calculate the geographical range, number of speakers, and rate of speaker decline for languages worldwide and map that data within square grid cells roughly 190 km across, spanning the entire globe. Although they were able to obtain information about the range and number of speakers for more than 90% of the world’s estimated 6909 languages, they could only glean details about the rate of decline or growth for 9%, or 649, of those languages, Amano notes. 
 
 Next, they looked for correlations between language loss and factors such as a country's gross domestic product and levels of globalization as calculated by an internationally recognized index. In addition, they examined environmental factors such as altitude, which might contribute to language loss by affecting how easily communities can communicate and travel. 
 
 Of all the variables tested, economic growth was most strongly linked to language loss, Amano says. Two types of language loss hotspots emerged from the study, published online today in the Proceedings of the Royal Society B. One was in economically well developed regions such as northwestern North America and northern Australia; a second was in economically developing regions such as the tropics and the Himalayas. Certain aspects of geography seemed to act as a buffer or threat, Amano says. For example, recent declines appear to occur faster in temperate climates than in the tropics or mountainous regions—perhaps because it is easier to travel in and out of temperate regions, Amano says. More research is necessary to determine precisely what it is about economic development that kills languages, he adds. Figuring out how growth interacts with other factors such as landscape is the next step, he says. 
 
 "This is the first really solid statistical study I've seen which shows principles about language decline that we've know about, but hadn't been able to put together in a sound way," says Leanne Hinton, a linguist at the University of California, Berkeley. Economics is far from the whole story, however, she says. In the United States, for example, current attitudes toward endangered tongues stem in large part from historical policies that forced young American Indians to eschew their native tongues in order to learn English, she says. Generations of disease, murder, and genocide—both historic and present, in some regions—have also played an important role and were not included in the new study's analysis, she says. 
 
 Although the study is silent on the subject of interventions to help preserve endangered languages, there is a range of revitalization efforts that can serve as examples, such as the incorporation of the Hawaiian language into school curricula and daily government operations, she says.
– There are some 6,909 languages spoken today, but many are on the decline, and the biggest reason, researchers find, is economic growth. Researchers studied the 649 languages for which growth and decline data was available to determine the leading factors driving the change, Science magazine reports. In order to reach their conclusions, they turned to methods typically employed to track endangered animal populations; interestingly, the study's lead author, Tatsuya Amano, is a zoologist. His team examined the relationships between a language's disappearance and a country's GDP, altitude, and other possible influences. Economic growth showed the strongest correlation to the fading of a language. "As economies develop, one language often comes to dominate a nation's political and educational spheres," Amano says, as per the BBC. "People are forced to adopt the dominant language or risk being left out in the cold—economically and politically." A quarter of the world's languages may be in danger, he notes; fewer than 25 people currently speak Upper Tanana in Alaska, for instance. (Meanwhile, the English language keeps growing.)