This is a reconstruction of Proto-Ersuic, the ancestor language of Lizu, Tosu, and Ersu, three closely related languages spoken in southwestern Sichuan which are generally considered to be part of the Qiangic branch of Tibeto-Burman. To date, no in-depth historical work has been carried out on these languages. Approximately 800 lexical items are reconstructed based primarily on data from six sources: Mianning Lizu (data collected by the author in Mianning County, Sichuan, in 2008 and 2010), two sources for Kala Lizu (Muli County, one modern and one older source), Naiqu Lizu (Jiulong County), and two varieties of Ersu (Zeluo and Qingshui, both in Ganluo County).
Chapter 1 provides a general introduction to Lizu, Tosu, and Ersu, along with basic information for each source to help the reader properly interpret the phonetic transcriptions and parse the individual forms for each language.
Chapter 2 presents the Proto-Ersuic syllable canon, providing the skeleton upon which the individual reconstructions are built.
Chapters 3 and 4 lay out the complete inventory of Proto-Ersuic initials and rhymes. All reconstructed consonants and vowels are supported by comprehensive cognate sets demonstrating regular sound correspondences across the languages, with exceptions carefully noted.
Chapter 5 offers a reconstruction of the lexical tones of Proto-Ersuic, with a general unmarked tone assigned to most words and a second, marked, tone of unclear origin specified on a minority of the lexicon.
Chapter 6 presents an outline of shared morphosyntax that can be reconstructed to the Proto-Ersuic level, specifically morphosyntax related to nouns, verbs, and numerals/classifiers.
Chapter 7 brings together all the sound changes that yielded the regular correspondences presented in Chapters 3 and 4, organizing them by language, and ordering them chronologically. From these sound changes emerges a picture of the internal structure (i.e. subgrouping) of Ersuic.
Chapter 8 takes a top-down approach, examining the sound changes from Proto-Tibeto-Burman to Proto-Ersuic and attempting to find regular patterns in the development of Proto-Tibeto-Burman rhymes, initials, and prefixes. Comparisons with other languages and branches of Tibeto-Burman are made as well in an attempt to uncover new roots.
The final chapter (Chapter 9) addresses the place of Proto-Ersuic in Tibeto-Burman, summarizing current views on the matter and offering some speculations on how the results of the present study might help us decide how Proto-Ersuic fits in the larger Tibeto-Burman family tree.