Harakmbut language

Harakmbut, also called Amarakaeri by outsiders though speakers prefer the endonym Arakmbut, is spoken along the Madre de Dios and Colorado rivers of Peru by an ethnic population numbering roughly 2,090 to 2,200 people as of the 2000s and 2013. It was accepted as a language isolate from the 1960s onward, but researchers have since proposed a connection to the Katukinan languages of Brazil under the name Harakmbut-Katukinan, a link Adelaar supported with lexical evidence that Campbell judged reasonably persuasive, while Glottolog notes promising lexical links but finds no supporting cognation in the languages' pronoun, numeral or bound-morphology systems. Two mutually intelligible but socially estranged dialects survive, Amarakaeri and Watipaeri, and as of 2012 children in some communities were still learning the language, even though literacy in Harakmbut stands at only about 5 percent compared with 75 percent in Spanish.