Growing a numeral system: The historical development of numerals in an Amazonian language family

Numerals in many languages around the world can be argued to reflect a progressive build-up of historical stages (cf. Hurford 1987), each of which may also represent the synchronic upper limit of a numeral system in another language. This paper presents an intriguing test case of this claim by exploring the historical development of numerals in the languages of the Nadahup (Makú) family of the northwest Amazonian Vaupés region, in which the numeral strategies that can be inferred diachronically for one language are also represented synchronically in its sisters. The paper also demonstrates that even the most basic of the Nadahup numerals have transparent etymologies (a cross-linguistically unusual feature suggestive of their relatively recent development), and that areal diffusion contributed to the expansion of the systems, supporting the characterization of the Vaupés as a linguistic area.