DAVOS, SWITZERLAND-Uldariko Matapi Yucuna, 63, is often called the last shaman of the Matapi, an indigenous group of fewer than 70 people living along the Miriti-Paraná River in Colombia’s Amazon rainforest. His father was a shaman and taught him ancestral knowledge, including how to use plants to treat all manner of ailments. But Uldarico rejects the title because instead of living with his people, he has spent the last 30 years in Bogotá documenting in writing what remains of that knowledge.
Once a nomadic people, in the 1980s the Matapi were forced to live on a reservation with five other ethnic groups, where traditions and language, already threatened by colonization, withered further. “We are losing the essence of our spiritual knowledge of medicinal plants,” says Uldariko, whose surname is that of his tribe. “Knowledge that cannot be translated into other languages.”
A study presented at World Biodiversity Forum in 2022 here last week reveals that many local groups face Uldarico’s dilemma. By linking linguistic and biological information, the authors show that most indigenous knowledge about medicinal plants is associated with endangered languages, and that language loss is an even greater threat to the survival of such knowledge than biodiversity loss. “Every time a local language dies, it’s like a library on fire, but we don’t see it because it’s silent,” says study co-author Rodrigo Camara Leret, a biologist at the University of Zurich (UZH).
Of the 7,000 indigenous languages still spoken, 40% are at risk of extinction, according to the United Nations. And 80% of the remaining biodiversity in the world is in local territories.
In the new study, researchers scoured the literature, including early records from colonizers, to map medicinal plant use and indigenous languages in three regions — North America, the northwestern Amazon, and New Guinea. They found about 12,000 medicinal uses for more than 3,000 plants known to people who speak 230 local languages in these regions. But more than 75% of this knowledge is found in just one of these languages.
Such knowledge is diverse. The Tucano of the Rio Negro in Brazil, for example, uses tree bark Leptolobium nitens in the arrows to paralyze the animals they hunt. The Siona people of Colombia and Ecuador apply milky latex from the tree Euphorbia hirta to treat fungal infections of the feet.
“Most of this knowledge is unique,” says Jordi Bascompte, an ecologist at UZH and co-author of the study, which was also published in Proceedings of the National Academy of Sciences. “If a language disappears, it is lost.”
The United Nations lists all indigenous languages in the western Amazon as endangered, making the accumulated botanical knowledge of these groups also endangered. In North America, endangered languages account for 86% of unique medicinal plant knowledge; the figure was 31% in New Guinea, according to the study.
The authors say this knowledge begins to erode even before languages disappear. In some studied groups, current speakers no longer recognize medicinal plants or do not know what mixtures to make and how to prepare them, says Cámara Leret. “There are no apprentices,” he says. “With word of mouth, if you don’t tell others while you’re alive, it goes away.”
Uldarico adds that translation is not enough to convey his culture’s knowledge of how to use plants for healing. A shaman is both pharmacist and doctor, with knowledge that goes beyond plant identifications that can be translated or simply matching a plant with a symptom, he says.
Much knowledge may already have disappeared without being recorded, the researchers note. “We’ve only covered the tip of the iceberg,” says Kamara Lerett.
In contrast to the high proportion of endangered languages, less than 4% of the medicinal flora in the three regions covered by the study is threatened with extinction. “We are losing knowledge at a faster rate than biodiversity,” says Bascompte.
The results are consistent with previous research, says Victoria Reyes-Garcia, an anthropologist at the Catalan Institute for Scientific Research and Advanced Studies. Her team’s research with the Tsimane people of Bolivia show that adults lose about 3% of their knowledge of plant use each year, which is much higher than expected rates of total biodiversity loss worldwide.
Without local knowledge, valuable natural compounds that could generate medicines can be lost. Less than 5% of the medicinal plants used by the Tikuna people, whose ethnobotanical knowledge is one of the most well-studied in the Amazon, have been tested for their biological activity, says Camara Leret.
Local cultures preserve ancient knowledge beyond that of medicine, adds linguist Ana Vilasi Galluccio of the Emilio Goeldi Paraense Museum in Brazil. “Indigenous languages encompass entire knowledge systems about biodiversity, social organization and environmental management,” says Gallusio, who works on projects to document and revitalize indigenous languages.
“The loss of culture is also a loss of our ability to adapt and find solutions to growing environmental problems,” adds Tania Eulalia Martínez Cruz, an indigenous Ayuk woman from Mexico and a social science researcher at the University of Brussels. She notes, for example, how the indigenous people of Oaxaca, Mexico, developed ways to grow plants in times of drought.
For Uldariko, cultural and environmental threats are two sides of the same coin. “The complexity of medicinal plants is territorial knowledge,” he says. “When you destroy territory, you destroy nature, knowledge, our practices and our lives.”
This story was produced as part of Internews’ Earth Journalism Network’s Biodiversity Media Initiative travel grant to the 2022 World Biodiversity Forum.