[IJAL vol. 77, no. 4, October 2011, pp. 521–36] © 2011 by The University of Chicago. All rights reserved. 0020–7071/2011/7704–0004$10.00 521 THIRD-PERSON AGREEMENT AND PASSIVE MARKING IN TACANAN LANGUAGES: A HISTORICAL PERSPECTIVE 1 Antoine Guillaume Laboratoire Dynamique Du Langage, CNRS, and Université Lyon 2 The ive Tacanan languages (Amazonian Bolivia and Peru)—Araona, Cavineña, Ese Ejja, Reyesano, and Tacana—have a conspicuously similar verbal suix -ta (or -ka in one dialect of Ese Ejja). Depending on the language and the transitivity of the verb stem it attaches to, this suix is used either to refer to a third-person plural S argument or a third-person singular or plural A argument, or to mark a passive derivation. In this paper, I argue that the suixes are all historically related and that they come from a single source: a third-person plural suix *-ta. I also suggest that this marker could have originated in a third-person plural independent pronoun that I reconstruct as **tuna. [Keywords: Amazonian languages, Tacanan languages, passive, third-person agree- ment, transitivity] 1. Introduction. The Tacanan family consists of ive languages: Araona, Cavineña, Ese Ejja, Reyesano (Maropa), and Tacana. These lan- guages are still spoken today, although the number of speakers is very low (approximately 111 for Araona, 601 for Cavineña, 518 for Ese Ejja, 12 for Reyesano, and 50 for Tacana, according to Crevels and Muysken 2009). As is the case for the majority of Bolivian lowland languages (and, more generally, Amazonian languages), the Tacanan languages had not been studied extensively until recently. They were irst documented through word lists col- lected by travelers and missionaries, starting in the nineteenth century, and made known to the academic world by the work of historical linguists—nota- bly Brinton (1891; 1892), who was the irst to propose a Tacanan group, and Schuller (1933), who was the irst to hypothesize a genetic link to the larger family of Panoan languages spoken in Amazonian Brazil, Peru, and Bolivia. The second wave of documentation of the Tacanan languages took place between the 1950s and 1980s when the Summer Institute of Linguistics (SIL) settled in Bolivia. SIL missionaries elaborated writing systems and produced 1 The ideas developed in this paper beneited from comments made by the participants in the workshop on “Argument-Coding in Lowland Bolivian Languages” (CELIA, Villejuif, April 5–7, 2007), the annual conference of the Society for the Study of Indigenous Languages of the Americas (SSILA, Chicago, January 3–6, 2008), and the third conference of the Syntax of the World’s Languages (SWL3, Berlin, September 25–28, 2008). This article was also improved by comments from Denis Creissels, Spike Gildea, Marc Peake, Françoise Rose, and an anonymous IJAL associate editor. Finally, I am indebted to the speakers of Cavineña, Reyesano, and Tacana who have shared their languages with me during my ieldwork in their communities.