M.A. Theses in Linguistics at the University of North Dakota (Abstracts)
Leander, Anita J. 2008
Acoustic Correlates of Fortis/Lenis in San Francisco Ozolotepec Zapotec
Analyses of the Zapotec family of languages often divide consonants into categories of strong and weak consonants, more commonly known as fortis and lenis. These given categories usually correspond to voiceless and voiced, respectively. In San Francisco Ozolotepec Zapotec (SFOZ) and Santa Catarina Xanaguía Zapotec (SCXZ), prior analyses describe the fortis/lenis distinction in terms of duration, voicing, and articulatory force. This description parallels other impressionistic descriptions in Isthmus-Valley and Southern Zapotec variants. However, no study has objectively identified the acoustic patterns of the fortis/lenis contrast in SFOZ or in any Southern, Valley, or Isthmus Zapotec language. A previous instrumental study of the northern Zapotec variant of Yateé describes the fortis/lenis contrast in terms of duration, glottal width, and closure width. A similar experimental study of the northern variant spoken in Yalálag describes the fortis/lenis contrast in terms of duration, voice onset time (VOT) and voicing, and amplitude. Both conclusions reject the terms fortis/lenis and point to characterization of the contrast in terms of geminate/single.
My intention in this thesis is to present acoustic analyses of recordings made by native Zapotec speakers of both SFOZ and SCXZ. I analyze the acoustic properties of the word-final fortis/lenis consonant contrast of SFOZ, with occasional reference to data from SCXZ. Parallel to instrumental results for Yalálag Zapotec (Avelino 2001) and Yateé Zapotec (Jaeger 1983), duration is a primary characteristic differentiating fortis and lenis consonants in SFOZ and SCXZ. Data from six adult male speakers of SFOZ reveal a second acoustic correlate of fortis and lenis segments in word-final position, quality of the preceding vowel. Voicing and VOT add to the phonetic contrast, but are not reliable cues in SFOZ. In contrast with Jaeger’s results, which found that “fortis consonants have consistently higher…average amplitudes than those of the lenis consonants” (1983:183), I found no difference in the average amplitude of fortis/lenis sonorants. In contrast with variation in sonorants in Yalálag, SFOZ sonorants – both nasals and laterals – match the duration patterns of obstruents: fortis consonants are long and lenis consonants are short. In SCXZ, obstruents can be defined in terms of voicing; however this distinction is considerably less reliable in SFOZ.
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