One reason is because half of all languages are spoken by fewer than 2,500 people each, according to the Worldwatch Institute, a private organization that monitors global trends.
Languages need at least 100,000 speakers to survive the ages, says UNESCO, the United Nations Educational, Scientific and Cultural Organization.
War and genocide, fatal natural disasters, the adoption of more dominant languages such as Chinese and Russian, and government bans on language also contribute to their demise.
"In some ways it's similar to what threatens species," said Payal Sampat, a Worldwatch researcher who wrote about the issue for the institute's May-June magazine.
Marie Smith is one of the endangered speakers. She is the last known speaker of Eyak, a language native to Alaska and one that is expected to become extinct when the 83-year-old Smith passes away.
"It's horrible to be alone," she said on Monday. "I have a lot of friends. I have all kinds of children yet I have no one to speak to" in Eyak.
Udihe and Arikapu, spoken in Siberia and the Amazon jungle, are among the endangered. About 100 people speak Udihe and Arikapu is down to its last six speakers, Worldwatch says.
It's becoming a struggle, too, to find many who can say "thank you" in the Navajo language of the American Indian tribe (ahehee), "hello" in the Maori language of New Zealand (kia ora), or state proudly in Cornish: "Me na vyn cows Sawsnak!" (I will not speak English!).
The losses ripple far beyond the affected communities. When a language dies, linguists, anthropologists and others lose rich sources of material for their work documenting a people's history, finding out what they knew and tracking their movements.
And the world, linguistically speaking, becomes less diverse.
In January, an earthquake in western India killed an estimated 30,000 speakers of Kutchi, leaving about 770,000.
Manx, from the Isle of Man in the Irish Sea, disappeared in 1974 when its last speaker died. In 1992, a Turkish farmer's passing marked the end of Ubykh, a language from the Caucasus region with the most consonants on record, 81.
Eight countries account for more than half of all languages. They are, in order: Papua New Guinea (832 languages), Indonesia (731), Nigeria (515), India (400), Mexico (about 300), Cameroon (about 300), Australia (about 300) and Brazil (234).
That languages die isn't new; thousands are believed to have disappeared already.
Linguists believe 3,400 to 6,120 languages could become extinct by 2100, a statistic much grimmer than the common estimate of about one language death every two weeks.
But some languages are coming back from the dead, so to speak.
In 1983, Hawaiians created 'Aha Punana Leo to reintroduce their native language throughout the state, including its public schools. Hawaiian nearly became extinct after the United States banned schools from teaching students in the language after annexing the country in 1898.
'Aha Punana Leo, which means "language nest," opened Hawaiian-language preschools in 1984, followed by secondary schools that produced their first Hawaiian-taught graduates in 1999.
Some 7,000 to 10,000 Hawaiians currently speak their native tongue, up from fewer than 1,000 in 1983, said Luahiwa Namahoe, the organization's spokeswoman.
"We just want Hawaiian back where she belongs," Namahoe explained. "If you can't speak it here, where will you speak it?"
Elsewhere, efforts are under way to revive Cornish, the language of Cornwall, England, that is believed to have died around 1777, as well as ancient Mayan languages in Mexico.
Hebrew evolved in the last century from a written language into Israel's national tongue, spoken by 5 million people. Other initiatives aim to revive Welsh, Navajo, New Zealand's Maori and several languages native to Botswana.
Governments can help by removing bans on languages, and children should be encouraged to speak other languages in addition to their native tongues, said Worldwatch's Sampat, who is fluent in French and Spanish and grew up speaking the Indian languages of Hindi, Marathi, Gujarati and Kutchi.
Some of the Worldwatch findings:
- North America: Eighty percent of the 260 native languages still spoken in the United States and Canada aren't being learned by children, one reason for language loss.
- South America: Hundreds of languages died as a result of the Spanish conquest. About 80 percent of the continent's remaining 640 languages are spoke by fewer than 10,000 people each.
- Africa: In the birthplace of nearly one-third of the world's languages, 54 are believed dead, with another 116 nearing extinction.
- Asia: More than half of Asia's native languages have fewer than 10,000 speakers each, although 3 billion people, or half the world's population, live on the continent.
- Australia: About 90 percent of its 250 aboriginal languages face extinction.
- Europe: Nearly 90 percent of Russians speak Russian, the language enforced during the Soviet era. Consequently, most of the country's 100 other native languages are near extinction.
India has 15 official languages, more than any other nation.
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