Ethiopian Semitic languages all have some form of internal reduplication. The characteristics of Tigre reduplication are described here, and are shown to diverge from the other languages in two main respects: i) the meaning and ii) the ability to incur multiple reduplication of the reduplicative syllable. The formation of internal reduplication is accomplished via infixation plus addditional templatic shape requirements which override many properties of the regular verb stem. Further constraints on realization of the full reduplicative syllable outweigh restrictions on multiple repetition of consonants, particularly gutturals.

This dissertation presents both a descriptive and a formal account of palatalization patterns as identified in a balanced sample of 117 languages. I distinguish between two palatalization types, one involving a primary place of articulation change (full palatalization, e.g. t--> tS), the other involving the acquisition of a secondary palatal articulation (secondary palatalization, e.g. t--> tj). The focus is on similarities/differences in palatalization patterns due to the place of articulation of target consonants, and on palatalization triggers. I develop a formal analysis which uses Articulatory Phonology (AP) and Optimality Theory (OT), making crucial reference to the oral articulators (lips, tongue) that produce the sounds involved in palatalization and their interaction during speech production.

Two main patterns are identified regarding palatalization triggers: (i) if lower front vowels are triggers, so are higher front vowels; (ii) if high back vowels are triggers, so are high front vowels. Regarding palatalization targets, I identify a striking dependency of labial palatalization on the palatalization of coronal and dorsal consonants: while coronal and dorsal palatalization can be independent or co-occurring in a given language, labial palatalization is always dependent on the palatalization of coronals and dorsals. Furthermore, labials do not undergo full palatalization. The few cases where this appears attested are explained via diachronic changes which did not involve palatalization of the labial itself. Historical evidence indicates that a palatal glide following the labial hardened to a palatal consonant, and that the labial ultimately deleted.

The proposed account explains the occurrence of palatalization, as well as the general palatalization patterns and labial palatalization. Paltalization is viewed as the result of temporal overlap of articulatory gestures produced with the two major articulators, tongue and lips. Full palatalization results from great overlap of tongue gestures, and secondary palatalization results from minimal overlap of tongue/tongue or lips/tongue gestures. The formal OT implementation relies on constraints that have an articulatory motivation and also capture the dependency of labial palatalization on the palatalization of coronal and dorsal consonants. The results of the crosslinguistic study and the formal analysis demonstrate that phonetic articulation must be incorporated in the explanation of phonological patterns.

In very general terms, phonology is the study of both the representational and computational properties of human sound patterns. These issues have been the focus of descriptive, formal, typological, and experimental work. This dissertation draws on experimental and fieldwork data from vowel harmony in four Central Asian Turkic languages, Kyrgyz, Kazakh, Uyghur, and Uzbek, to examine the computational and representational nature of vowel harmony patterns.

One perennial computational question relates to the nature of phonological dependencies – how local must they be? In the dissertation I examine reported transparency in Uyghur backness harmony to evaluate previous analyses of transparent /i/ in the language. Results indicate that putatively transparent vowels actually undergo harmony, which in turn suggests that the analysis of Uyghur is computationally far simpler than previously thought. The dissertation also investigates the strictness with which locality is evaluated, comparing various proposals concerning the participation of consonants in vowel harmony, developing a more nuanced understanding of the interplay between phonetics and phonology that accounts for segment-intrinsic resistance to coarticulation in harmony.

In addition to locality, the dissertation examines the nature of phonological representations. Structuralist and Generative research has generally assumed that phonology manipulates abstract categorical variables, in contrast to the gradient variables that pervade phonetics. As an example, Zsiga (1997) argues that vowel harmony, in contrast to gradient phonetic assimilation, produces categorical alternations between target vowels whose output forms are indistinguishable from their triggering counterparts. Results from an acoustic study suggest that backness harmony in Kazakh and Uyghur produces output sounds that systematically differ from trigger vowel qualities, with the assimilatory effect of harmony gradiently petering out across the word. After comparing findings to plausible phonetic and phonological accounts, I argue that the best account of the data involves gradient phonology. Throughout the rest of the dissertation I develop the claim that phonology may be gradient, examining gradience in harmony from perceptual, formal, and typological perspectives.

Laz Turkish (LT) is a nonstandard variety of Turkish mainly spoken by the Laz minority in the northeast of the Black Sea Region in Turkey. LT emerged a second language variety of Turkish and developed into its own distinct dialect in a language contact situation between Turkish (Turkic) and Laz (South Caucasian), and it has been shifting towards Standard Turkish (ST) under the influence of the dominating Turkish culture. Laz has a smaller vowel system compared to Turkish and this has impacted the vowel harmony (VH) system in LT. In contrast to ST, which has a very productive VH system, LT has only partially productive VH. Based on a corpus of fieldwork data, this dissertation investigates how LT displays partial VH in morphologically complex forms. This dissertation also situates LT in a sociolinguistic context by investigating the attitudes in the Laz community towards Laz, LT and Laz identity, and examines the underlying causes of the language shift from LT to ST. This dissertation shows that LT contains forms that are identical to ST, which satisfy VH wherever applicable, as well as forms that show unique characteristics (LT-unique forms), which often do not conform to VH. The main findings of this dissertation regarding the LT-unique forms are as follows. First, three Turkish vowels that are absent in the Laz vowel system, [ɯ, y, œ], are rare in LT-unique forms. ST [ɯ, y, œ] correspond to LT [i, u, o], preserving rounding feature of vowels. This correspondence pattern is especially observed in the first syllable of LT words. Second, non-initial suffixes with high vowels are typically of two kinds: [i] and [u]. The distribution of these vowels cannot be attributed to VH, but it is predictable by syllable type: [i] primarily occurs in open syllables and [u] in closed syllables. Such distribution of high vowels based on syllable structure is likely to be an L1 (Laz) influence. Non-high vowels [a, e] in LT-unique forms do not show correlation with syllable type, and they typically satisfy VH. Overall, there is weak evidence for VH in LT-unique forms, especially for high vowels.

Characteristics unique to LT are produced more consistently by the elderly LT speakers compared to the younger ones. This generational shift from LT to ST is due to increased exposure to ST, which is especially promoted in the context of educational and governmental institutions. However, LT or LT speakers are characterized in the media or other social domains as an object of ridicule. In general, members of the Laz community have positive attitudes towards Laz, LT, and Laz identity. Nevertheless, they also notice the negative stereotypes outside the community.

The findings of this dissertation contribute to our understanding of i) what happens when L1 has a smaller vowel system compared to L2, ii) which patterns emerge when native speakers of a language without VH acquire a VH language as an L2, and iii) whether these patterns can be attributed to the acquisition of the L2 vowel system or other factors linked to L1 phonology.

This dissertation documents and analyzes phonetic and phonological features of Gua, an under-documented, understudied and nearly-endangered Guang language, spoken in the Eastern Region of Ghana. The language has two dialects, Anum and Boso. The data for this dissertation is from the Boso dialect spoken in the Boso community. The dissertation focuses on the properties of the sound system which includes the segmental inventory, tone, and processes such as vowel harmony, hiatus resolution, consonant assimilation and nasalization, and their interactions with other areas of the grammar. Chapter 1 provides a general introduction to Gua including a sociolinguistic survey. It also situates the scope and the relevance of the study. Chapter 2 presents the vowel inventory in the language. It discusses the different properties of the vowels including oral and nasal vowels, Advanced Tongue Root (ATR) distinctions, vowel length and vowel sequences. Acoustic measurements are provided to show the positions of oral and nasal vowels in the F1/F2 vowel space. The chapter also presents the syllable structure which consists of open syllables, no complex onsets or codas, and only nasal consonants as possible codas. Nasals may also serve as syllabic consonants. Chapter 3 presents the basic patterns of word-internal ATR vowel harmony and directionality which is robustly regressive within words, roots, and across words. Chapter 4 presents a description of cross-word harmony and demonstrates how the process is sensitive to both prosodic phrasal units as well as syntactic structure. Chapter 5 describes and analyzes consonants. Gua has voicing contrasts among stops and affricates at six places of articulation, including labio-velar stops. It also has a series of nasal consonants. The chapter presents consonant interactions that involve nasals and stops in the verbal prefix complex. These processes include nasal place assimilation, nasal assimilation and stop deletion. In Chapter 6, two processes are introduced that affect vowel realization: nasalization and vowel hiatus. Gua has a series of nasal vowels and also shows tautosyllabic nasalization of vowels triggered by either onsets or codas. This process interacts with ATR harmony, both within and across words. The chapter shows how nasal vowels are fully participatory in vowel harmony, and even though Gua lacks phonemic mid +ATR nasal vowels /ẽ, õ/, like many West African languages (Hyman 1972, Rolle 2013), these vowels can be created as allophones via the interaction of nasalization and/or ATR vowel harmony. The second section discusses the resolution of vowel hiatus (Casali 1997/2011) across morpheme and word boundaries, showing all combinations of sequences of oral vowels. The vowel hiatus resolution patterns interact with ATR harmony, leading to opacity on the surface. Chapter 7 is dedicated to the discussion of tone and tone processes. Gua is a two tone language with downstep. It also has both lexical and grammatical tone. Lexical tone distributions are tightly bound to word class in nouns, adjectives and postpositions. In verbs, tone is grammatical and there are no lexical distinctions among verb roots. Tense, mood and aspect correlate with one of three tone melodies that extend across the root. Monomoraic roots cannot host a contour tone, and how the tone melody reduces depends on the presence of a prefix. In addition, some verbal prefixes show tone polarity effects. Subject markers alternate tone based on the tone of the following tone-bearing unit. TAM prefixes display opposite tone to the following tone-bearing unit, also creating a tone polarity effect. The dissertation contributes to the description and analysis of the grammar of Guang languages. It also contributes to the typological study of phonologies of the world’s languages.

Though the majority of the world’s population is bilingual, most of the existing research on child language acquisition has focused on monolinguals. Increasingly, research has begun to investigate language acquisition in bilingual contexts, and has found evidence of both similarity to and difference from patterns found in monolingual language acquisition. One evident source of difference in bilingual language acquisition is interaction, where bilinguals’ acquisition of one language affects their acquisition of the other language. Interaction has been shown to occur at multiple levels of linguistic structure (syntactic, phonological, phonetic), and manifests in three different patterns: acceleration, deceleration, and transfer. Acceleration and deceleration refer to the rate at which bilinguals acquire some property relative to monolinguals in the same language. Acceleration occurs when bilinguals acquire some property faster or earlier compared to monolingual peers, whereas deceleration occurs when bilinguals acquire some property later or more slowly than monolingual peers. Transfer refers to bilinguals’ use of a property specific to one language in their other language. While the occurrence of each of these patterns has been demonstrated in bilinguals’ language acquisition, it is not well understood what causes interaction to occur where and how it does. In this dissertation, I propose that frequency of occurrence and linguistic complexity, both features of the input that are known to affect the course of monolingual acquisition, also direct the appearance of interaction in bilinguals’ acquisition of language. I present findings from a series of studies demonstrating that differences between languages in frequency of occurrence and complexity of phonological properties influence bilinguals’ acquisition of aspects of Spanish and English phonotactics in predictable ways. Specifically, greater frequency of occurrence and greater complexity of phonological properties in one language are shown to promote bilinguals’ acquisition of related phonological properties in their other language.

Kenyan Sign Language (KSL) is a thriving national sign language used by tens of thousands of signers in Kenya, and which emerged out of two deaf schools in western Kenya in the early 1960s. In this thesis, I provide a thorough description and analysis of the basic phonological components of the KSL lexicon used in the southwestern region of Kenya (formerly south Nyanza Province).

This phonological grammar of (SoNy)KSL makes contributions in three domains. In the descriptive domain, it provides a thorough report of the basic units in the main phonological parameters; i.e., Handshape (Ch. 4), Location (Ch. 5), and Movement (Ch 6, 7), as well as the evidence for the distinctiveness of each unit. The description for Movement and Location are particularly noteworthy because those parameters have received less attention in sign linguistics in general compared to Handshape.

In the methodological domain, the grammar is based on a KSL Lexical Database built for this project, in which over 50 phonetic characteristics of 1,880 non-compound signs were coded. This database is currently one of only a few such richly coded lexical databases of sign languages. In addition, this grammar employs a rigorous approach to determining lexical contrast, which has yielded a separate dataset of 461 minimal pairs (Ch. 3). This dataset is unique in sign linguistics and reveals patterns of lexical contrast that were not previously known—and which have generated new hypotheses about how lexical contrast may be constrained by degrees of visual similarity.

Finally, this thesis makes a theoretical contribution by comparing how different models of sign phonology can account for sign types in KSL. By evaluating the explanatory power of the main theories of sign phonology on the basis of specific descriptive data, this thesis gives unique insights into the theoretical validity of these models. It also proposes modifications in some cases, especially with regard to how the Dependency Model (DPM) can account for the representation of movement features and their relationship to the timing tier. In addition, a new movement feature, [dispersed], is described and its implementation worked out in the DPM.

The overarching goal of this dissertation is to advance our understanding of linguistic tone and the role it plays in the organization of morphological systems. This topic is explored through a typological study, a case study, and a comparative study.

The first study presents a typology of tonal exponence, couched within an Abstractive Word-and-Paradigm approach to morphology. It builds on previous studies on exponence typology by extending it to the study of tone, and explores deviations from form-function isomorphism, polyfunctionality, morphomic distributions, paradigmatic layers, and inflectional class organization. It is argued that the attested diversity of form-function mappings constitutes an empirical argument for a paradigm-based view of morphology, where the range of encoding strategies are treated as equivalent, as opposed to choosing form-function isomorphism as the theoretical ‘ideal’.

The second study contributes to the documentation of tone and morphology in Tira (Heiban; Sudan), a previously understudied language. It is shown how tonal and non-tonal exponents interact in distinguishing verb forms in Tira. The system exhibits complexity of exponence in the sense that there is non-isomorphism between form and function; the meaning of the verb forms is distributed across different markers. It is argued that to understand the nature of the system, both the syntagmatic and the paradigmatic dimension need to be addressed, and an analysis is proposed by identifying a set of implicative relations, zones of interpredictability, and principal parts.

The third study is a comparative morphological study of the West Heiban languages Tira and Moro. It presents novel data illustrating subject and object marking on verbs in Tira and compares this to previously published works on Moro and the Central Heiban languages. Based on similarities and differences across the verb systems, Moro is argued to be innovative in several areas, and a series of diachronic developments are proposed to account for these facts. It is proposed that Moro has undergone a tonally conditioned constructional change whereby prefixed object markers became suffixes in verb forms associated with a specific tone pattern. This shows that tone may play an active role in language change and contribute to the reorganization of constructions.