Language extinction triggers the loss of unique medicinal knowledge

TLDR

More than 30% of the world’s 7,400 languages are projected to disappear by the end of the century, yet the extent to which language loss erodes unique medicinal knowledge remains poorly understood. This study investigates how indigenous medicinal plant knowledge is linked to individual languages and estimates the amount of such knowledge that could vanish with language and plant extinction. Across three bioculturally diverse regions, over 75% of 12,495 medicinal plant services are known to only one language, and most of those languages are threatened, indicating that language loss poses a greater risk to medicinal knowledge than biodiversity loss.

Abstract

Over 30% of the 7,400 languages in the world will no longer be spoken by the end of the century. So far, however, our understanding of whether language extinction may result in the loss of linguistically unique knowledge remains limited. Here, we ask to what degree indigenous knowledge of medicinal plants is associated with individual languages and quantify how much indigenous knowledge may vanish as languages and plants go extinct. Focusing on three regions that have a high biocultural diversity, we show that over 75% of all 12,495 medicinal plant services are linguistically unique-i.e., only known to one language. Whereas most plant species associated with linguistically unique knowledge are not threatened, most languages that report linguistically unique knowledge are. Our finding of high uniqueness in indigenous knowledge and strong coupling with threatened languages suggests that language loss will be even more critical to the extinction of medicinal knowledge than biodiversity loss.