Synchronic and diachronic morphoprosody : evidence from Mapudungun and Early English
Keywords: prosody
morphological typology
Middle English
mapudungun
stress
phonology
Old English
araucanian
language change

In the individual grammars of time-bound speakers, as well as in the historical transmission of a language, prosodic and morphological domains are forced to interact. This research focuses, in particular, on stress, and its instantiation in different domains of the morphological structure. It asks what factors are involved in prioritising one system – morphology or stress assignment – over the other and how radical the consequences of this may be on the overall structure of the language.
The data comes from two typologically distinct languages: Mapudungun (previously 'Araucanian'), a polysynthetic and agglutinating language isolate from Chile and Argentina documented for over 400 years; and English, far further into the isolating and fusional spectra, and documented from the 7th century onwards. In both languages, we focus on morphologically complex words and how they evolve in relation to stress. In Mapudungun we examine the entire historical period, while in English we focus on the changes from Old to Middle English (8th -14th centuries).
The analyses show how different types of data (from acoustics, to native and non-native intuitions; from historical corpora, to present-day experimentation techniques), can be used in order to assess whether the prosodic system will accommodate to the demarcation of morphological domains or whether morphological structure is to be shoehorned into the prosodic system's rhythmic pattern.
Original contemporary field and experimental work on Mapudungun shows stress to fall on right-aligned moraic trochees in the stem and word domains. This contradicts claims in the foot-typology literature, where Araucanian stress goes from left to right, building quantity-insensitive iambs. A reconstruction of the history of the stress system suggests a transition from quantity insensitivity to sensitivity and the establishment of two domains of stress, which ultimately facilitates the parsing of word-internal structure, emphasising the demarcative function of stress.
In the case of Early English, the focus is on the prefixal domain. Here the optimisation of the stress system – also trochaic – is shown to reduce the instances of clash in the language at large. As a result, a split in the prefixal system is identified, where prefixes constituting heavy, non-branching feet are avoided – and are ultimately lost – due to clash with root-initial stress, while light and branching feet remain in the language. In this case, it is the rhythmic or structural role of stress that is emphasised.
Language internal factors are evaluated – in particular morphological type and stress properties – alongside external factors such as contact (with Chilean Spanish and Norman French), in order to provide a more general context for the observed changes and synchronic structure of the languages. A key concept in the analysis is that of 'pertinacity', the conservative nature of transmission in grammars, which leads learners to perpetuate perceived core elements of the system.