AYAPAN, Mexico -- Only two people on Earth are known to speak the Ayapanec language, Manuel Segovia and Isidro Velasquez, old men of few words who are somewhat indifferent to each other's company.
When Segovia and Velasquez pass away, their language also will go to the grave. It will mark the demise of a unique way of describing the lush landscape of southern Mexico and thinking about the world.
Ayapanec isn't alone in its vulnerability. Some linguists say that languages are disappearing at the rate of two a month. Half of the world's remaining 7,000 or so languages may be gone by the end of this century, pushed into disuse by English, Spanish and other dominating languages.
The die-off has parallels to the extinction of animals. The death of a language, linguists say, robs humanity of ideas, belief systems and knowledge of the natural world. Languages are repositories of human experience that have evolved over centuries, even millennia.
"Languages are definitely more endangered than species and are going extinct at a faster rate," said K. David Harrison, a linguist at Swarthmore College in Pennsylvania and the author of the book "When Languages Die." "There are many hundreds of languages that have fewer than 50 speakers."
Hot spots for endangered languages may not be where you think. They include places such as Oklahoma, which holds the highest density of indigenous languages in the United States, partly because faraway tribes were forcibly relocated there in the 1800s; northern Australia, home to many small and scattered Aboriginal groups; and Central Siberia, which has 25 Turkic, Mongolic and other languages that face extinction.
In Mexico's Tabasco state, which faces the Gulf of Mexico, several languages and their dialects are in agony. Less than 2 miles northwest of the town of Ayapan is Cupilco, home to a handful of elderly residents who still speak a dialect of Nahuatl, the language of the ancient Aztecs. Linguists call the dialect "moribund" because no children speak it.
When Ayapanec and Cupilco Nahuatl die, bridges will not fall down. Ecosystems will not be disrupted. Few may notice. Language is an invisible triumph of humanity and its disappearance brings only silence.
"It's not as flashy as a pyramid but it represents enormous human achievement in terms of the thought and effort that went into it," said Daniel Suslak, a linguistic anthropologist at Indiana University who's about to publish a dictionary and grammar of Ayapanec.
Mexico, one of the world's most linguistically diverse nations, prides itself on its indigenous population, from the white-robed Lacandons in the southern jungles to the Tarahumaras, famed for their long-distance running through canyons in Chihuahua.
More than 9.8 million Mexicans speak any of some 68 distinct indigenous languages, with 364 dialects or variants. But the number is dropping.
"Many of these languages are spoken only by people 50 years old or older, and so no matter how much we wish it weren't so, they will disappear," said Arnulfo Embriz, the director of linguistic policy at the National Institute for Indigenous Languages.
That is the likely fate of Ayapanec, which is thought to have descended from a language spoken by the Olmecs, a pre-Columbian civilization that lived in the tropical lowlands near the Gulf of Mexico. Its speakers call the language "Nuumte Oote," or "the real voice."
Manuel Segovia was bathing when a visitor arrived at his one-story home in this hot flatlands town in the cacao-growing region of Tabasco. His 27-year-old son, Jose Manuel, said his father had taught him a little Ayapanec.
"I can speak some words, not 100 percent, maybe 25 percent," he said. "When you are grown like I am, you have other activities that take your time."
While foreign linguists now come to study Ayapanec, he said, chances are slim that its demise can be averted.
"It will be forgotten. Who will worry about reviving something that no one cared about when it was still alive?" he asked.
Segovia, 76, shuffled into the room and sat in a hammock. After a little prodding, he described how, when he was a boy, everyone in town "could speak the words." Then around 1940, an edict came from the capital.
"By order of the government, teachers would no longer teach the language or allow us to study it. ... They didn't want to hear it anymore," Segovia said.
The national oil industry boomed nearby, a road pierced the region and migrants speaking other indigenous languages, such as Chontal, as well as the dominant Spanish, moved to the village. Ayapanec-speaking residents became a minority. Some scattered.
For decades, Segovia lived with his elder brother, Esteban.
"Manuel and Esteban were so close to each other and lived with each other and spoke to each other every day, all day, in nothing but Ayapanec," said James A. Fox, a linguist at Stanford University who's worked to document and preserve the language on tape.
When Esteban died more than a decade ago, Manuel Segovia had hardly anyone left to speak to. A younger man he occasionally hired to tend to his cacao crops, Isidro Velasquez, could speak Ayapanec. But the two men aren't close. Mexican news reports suggested a feud.
Segovia, now dressed in the white shirt and red kerchief that's the traditional costume of the Ayapanec community, bristled at that. "Who told you that?" he blurted out. After it was explained that the matter had been aired in the Mexican media, Segovia volunteered to escort a visitor to Velasquez's home to prove that no rift existed.
Once there, the 68-year-old Velasquez greeted visitors without a shirt, displaying a tanned frame made sinewy by a lifetime of labor.
"I'm not very handsome for you to be taking photos of me," he said, a smile creasing his face. Several of his six children and multiple grandchildren passed through the room. None could speak Ayapanec, and Velasquez acknowledged that he hardly used the language anymore.
"I have two turkeys," Velasquez said, pointing to a back patio. "Sometimes I grab them and speak to them (in Ayapanec). They understand me."
His loud cackle needed no linguistic interpretation.
As Segovia noted, Ayapanec isn't fading away of its own volition. It's been pushed toward extinction through a combination of government policies and the overwhelming presence of Spanish, the national language.
Even as Mexico boasts of its indigenous heritage, with an eye on promoting tourism, it has done poorly in bilingual education, posting qualified teachers to areas where their language isn't spoken.
"Education is basically in Spanish," said Cristina Buenrostro, a linguist at the National Autonomous University of Mexico. "Those who speak an indigenous language begin to lose it on entering school."
FORCING A CHANGE
Languages can die of neglect when their speakers find that a new language coming into an area is more important or useful, but coercion is more common. In the 19th century, the U.S. government established federal boarding schools for Indian youth, requiring them to speak English and punishing them if they spoke their native tongues. Australia also forced English on its Aboriginal population.
"It happened in Spain under (Gen. Francisco) Franco. He discouraged the use of Basque in the same way by preventing its use in schools," Fox said, adding that such policies can backfire. Basque speakers took the pressure as reason to embrace the language.
But when native speakers have offspring who don't see the utility of their parents' tongue, the language also is doomed, experts say.
"I see this process as not benign," said Harrison, the Swarthmore expert and a strong advocate of language diversity. "It's not a rational thing where people see Spanish as better. They receive the message through mass media, through educational institutions and through society at large.
"If people weren't coerced into giving up their languages, they would keep them."
Harrison said no language had a monopoly on genius. Moreover, many dying languages contain valuable knowledge of the plants and animals in the environments in which they're spoken. Biologists even have determined that animals they'd thought of as a single species were in fact two, based on their descriptions in a minor language.
Ayapanec has a complex vocabulary for the creatures of the Gulf, recognizing six varieties of turtles and all manner of fish.
If more linguists aren't put to the task of analyzing and documenting endangered languages, some certainly will fade into oblivion. Experts need years to create grammar books, dictionaries, and audio and video recordings of personal histories.
By Harrison's reckoning, 85 percent of the world's languages have no proper documentation. As those languages fall silent, there may be no trace of what was lost.