It was first proposed by Swadesh (1954), and continues through Payne (1984) and Kaufman (1994).
Tovar (1984) proposed a connection between Zaparoan and the otherwise unclassified Taushiro; Stark (1985) and Gordon (2005) see a connection with the extinct Omurano language.
The extinct Awishiri and the Candoshi isolate have lexical similarities with Taushiro, Omurano, and each other; however, the four languages also have lexical similarities with Zaparoan, Jivaroan, and Arawakan.
These six languages and families in the table at right have not been linked in any coherent fashion.
This forms part of Kaufman's Macro-Andean proposal: This article related to the Indigenous languages of the Americas is a stub.