As a boy, Blas Omar Jaime spent many afternoons learning about his ancestors. Over yerba mate and torte fritas, her mother, Ederlinda Miguelina Yelón, passed on the knowledge she had stored in Chaná, a guttural language spoken by barely moving the lips or tongue.
The Chaná are an indigenous people of Argentina and Uruguay whose lives were intertwined with the mighty Paraná River, the second longest in South America. They revered the silence, considered the birds their guardians and sang lullabies to their children: Utalá tapey-‘é, uá utalá dioi – sleep little one, the sun has gone to sleep.
Ms. Miguelina Yelón urged her son to protect their stories by keeping them secret. So it was only decades later, recently retired and looking for people to chat with, that she made a surprising discovery: no one else seemed to speak Chaná. Scholars had long considered the language extinct.
“I said, ‘I exist.’ I’m here,’” said Mr. Jaime, now 89, sitting in his sparse kitchen on the outskirts of Paraná, a medium-sized city in Argentina’s Entre Ríos province.
Those words kicked off a journey for Mr. Jaime, who has spent nearly two decades resurrecting Chaná and, in many ways, putting the indigenous group back on the map. For UNESCO, whose mission includes the preservation of languages, it constitutes a fundamental repository of knowledge.
His painstaking work with a linguist produced a dictionary of approximately 1,000 Chaná words. For people of indigenous descent in Argentina, he is a beacon that has inspired many to connect with their history. And for Argentina, it is part of an important, if still fraught, reckoning over its history of colonization and indigenous erasure.
“Language is what gives you identity,” Mr. Jaime said. “If anyone does not have his language, he is not a people.”
Along the way, Mr. Jaime has had brushes with celebrity. The subject of numerous documentaries, he has Shipped to TED Talk, slow down his face and voice for a brand of coffee and appeared in an educational cartoon about the Chaná. Last year, a recording of him speaking Chaná echoed through in downtown Buenos Aires as part of an art project that sought to honor Argentina’s indigenous history.
Now the passing of the guard is underway in favor of daughter Evangelina Jaime, who learned Chaná from her father and is teaching it to others. (How many Chaná remain in Argentina is unclear.)
“There are generations and generations of silence,” said Ms. Jaime, 46. “But we will no longer be silent.”
Archaeologists trace the presence of the Chaná people to about 2,000 years ago in what are now the Argentine provinces of Buenos Aires, Santa Fe and Entre Rios, as well as parts of present-day Uruguay. The first European documentation of Chaná was made in the 16th century by Spanish explorers.
They fished, lived a nomadic life and were skilled clay craftsmen. With colonization, the Chaná were displaced, their territory shrank, and their numbers dwindled as they assimilated into newly formed Argentina, which launched military campaigns to eradicate indigenous communities and open up land for settlement.
Before Mr. Jaime revealed his knowledge of Chaná, the last known record of the language dates back to 1815, when Dámaso A. Larrañaga, a priest, met three older Chaná men in Uruguay and documented what he had learned about the language in two notebooks. Only one of those books has survived, containing 70 words.
The collection of information that Mr. Jaime obtained from his mother was much broader. Mrs. Miguelina Yelón was an adá oyendén – a “woman memory keeper” – someone who traditionally preserved the knowledge of the community.
According to Mr. Jaime, only women were custodians of Chaná’s memory.
“This was a matriarchy,” Ms. Jaime said. “Women were the ones who led the Chaná people. But something happened – we’re not sure what – that made the men regain control. And women agreed to give up that power in exchange for being the sole custodians of that history.”
Mrs. Miguelina Yelón had no daughters to pass on her knowledge to. (Her three daughters all died as infants.) So she turned to Mr. Jaime.
This is how he came to spend his afternoons immersing himself in the stories of the Chaná, learning words that described their world: “atamá” means “river”; “vanatí beáda” is “tree”; “tijuinem” means “god”; “yogi” is “fire”.
His mother warned him not to share what he knew with anyone. “Ever since we were born, we hid our culture, because back then you were discriminated against for being Aboriginal,” she said.
Decades passed. Mr. Jaime has led a varied life, working as a delivery boy, in a publishing house, as a traveling jewelry salesman, in a government transportation department, as a taxi driver and as a Mormon preacher. When he was 71 and retired, he was invited to an indigenous event and was invited into the crowd to tell his story.
Since then, Mr. Jaime hasn’t stopped talking.
One of the first to publicize it was Daniel Tirso Fiorotto, a journalist who worked for La Nación, the national newspaper.
“I knew this was a treasure,” said Mr. Fiorotto, who tracked down Mr. Jaime and published his first story in March 2005. “I walked out of there amazed.”
After reading Mr. Fiorotto’s article, Pedro Viegas Barros, a linguist, also met Mr. Jaime and found a man who clearly had fragments of a language, even if it had been eroded from lack of use.
The meeting marked the beginning of a collaboration that lasted years. Mr. Viegas Barros wrote several articles on the process of recovering the language, and he and Mr. Jaime published a dictionary that included Chaná legends and rituals.
According to UNESCOat least 40% of the world’s languages – or more than 2,600 – were at risk of disappearing in 2016 because they were spoken by relatively small numbers of people, the latest year for which reliable data is available.
Referring to Mr. Jaime, Serena Heckler, a program specialist at UNESCO’s regional office in Montevideo, Uruguay’s capital, said: “We are very aware of the importance of what he is doing.”
While her Chaná preservation work is not the only case of a language once thought dead suddenly reappearing, it is exceptionally rare, Ms. Heckler said.
In Argentina, as in other countries in the Americas, indigenous people have suffered systematic repression that has contributed to the erosion or disappearance of their languages. In some cases, children were beaten at school for speaking a language other than Spanish, Ms. Heckler said.
Saving a rare language like Chaná is difficult, he added.
“People need to commit to making it part of their identity,” Heckler said. “These are completely different grammatical structures and new ways of thinking.”
This challenge resonates with Ms. Jaime, who has had to overcome ingrained beliefs among the Chaná.
“It’s been passed down from generation to generation: Don’t cry. Don’t show yourself. Don’t laugh too loud. Speak slowly. Don’t say anything to anyone,” she said.
For a time, this is how Mrs. Jaime also lived.
She avoided her ancestors as a teenager because she was bullied at school and scolded by teachers who doubted her when she said she was Chaná.
After her father began public speaking, she helped him organize the language courses he offered at a local museum.
In the process, he began to learn the language. She now teaches Chaná online to students from around the world: many are academics, although some say they have traces of indigenous ancestry, with a small number believing they may be descendants of Chaná.
He plans to teach the language to his now adult son so he can continue the family’s work.
Back at Mr. Jaime’s kitchen table, the older man has written his name in the language he is trying to keep alive. It was a name that he said reflected the way he lived. “Agó Acoé Inó”, which means “dog without owner”. Her daughter read to make sure she wrote it correctly.
“Now he knows more than me,” he said, laughing. “We will not lose Chaná.”