The English definite article has two major allomorphs: prevocalic /ðiː/ and preconsonantal /ðə/. Recent studies have shown changes to definite article allomorphy in some English varieties. Younger speakers, particularly from culturally and linguistically diverse backgrounds, often use /ðə/ prevocalically rather than /ðiː/. The prevocalic definite article (PVDA) /ðiː/ facilitates management of vowel hiatus because it supports the emergence of [j] in preventing vowel adjacency (e.g. the ash [ðiːjœʃ]). An alternative strategy for separating adjacent vowels is glottalisation or glottal stop ([ðiːʔœʃ]). Few studies have explored the relationship between the vowel in the PVDA and hiatus management during the process of change. We report a diachronic analysis of Australian English (AusE) PVDA and associated hiatus management across a 50-year period (∼1960s to ∼2010s) and a synchronic analysis of present-day speakers from mainstream (MS) and non-mainstream (non-MS) (diverse) backgrounds using two read-sentence contexts. The aim is to provide insight into the process of change and factors that may influence its progression. Speech data from adolescents recorded in 1959/1960 were compared with recordings from Mainstream AusE-speaking (MS) young people recorded in the 2010s. Results showed significantly greater incidence of schwa in the PVDA and hiatus-breaking glottalisation in the modern data, particularly amongst females. The synchronic analysis comparing present-day MS and non-MS speakers showed increased use of glottalisation in females and non-MS speakers. Additionally, acoustic analysis showed more schwa-like productions in the PVDA by non-MS speakers. Of key importance in both analyses is that glottalisation was more prevalent than schwa, possibly indicating glottalisation triggered the change.

Hiatus occurs when the juxtaposition of syllables results in two separate vowels occurring alongside one another. Such vowel adjacency, both within words and across word boundaries, is phonologically undesirable in many languages but can be resolved using a range of strategies including consonant insertion. This paper examines linguistic and extralinguistic factors that best predict the likelihood of inserted linking ‘r’ across word boundaries in Australian English. Corpus data containing a set of 32 phrases produced in a sentence-reading task by 103 speakers were auditorily and acoustically analysed. Results reveal that linguistic variables of accentual context and local speaking rate take precedence over speaker-specific variables of age, gender and sociolect in the management of hiatus. We interpret this to be a reflection of the phonetic manifestation of boundary phenomena. The frequency of the phrase containing the linking ‘r’, the frequency of an individual's use of linking ‘r’, and the accentual status of the flanking vowels all affect the /ɹ/ strength (determined by F3), suggesting that a hybrid approach is warranted in modelling liaison. Age effects are present for certain prosodic contexts indicating change in progress for Australian English.

Australian English is a regional dialect of English which shares its phonemic inventory with Southern British English through the historical connection with the dialects of the British Isles (in particular London) in the late 18th and early 19th centuries (Cochrane 1989, Yallop 2003, Leitner 2004). Speakers of present-day Australian English are typically those who are born in Australia or who immigrate at an early age when peer influence is maximal. Such speakers fall into three major dialect subgroups: Standard Australian English, Aboriginal English and Ethnocultural Australian English varieties. Standard Australian English (SAusE) is the dominant dialect and is used by the vast majority of speakers. It is a salient marker of national identity, and is used in broadcasting and in public life. The Aboriginal and Ethnocultural varieties are minority dialects allowing speakers to express their cultural identity within the multicultural Australian context (Cox & Palethorpe 2006, Clyne, Eisikovits & Tollfree 2001).

In this paper we analyse the extent to which an adult's vowel space is affected by vowel changes to the community using a database of nine Christmas broadcasts made by Queen Elizabeth II spanning three time periods (the 1950's; the late 1960's/early 70's; the 1980's). An analysis of the monophthongal formant space showed that the first formant frequency was generally higher for open vowels, and lower for mid-high vowels in the 1960's and 1980's data than in the 1950's data, which we interpret as an expansion of phonetic height from earlier to later years. The second formant frequency showed a more modest compression in later, compared with earlier years: in general, front vowels had a decreased F2 in later years, while F2 of the back vowels was unchanged except for [u] which had a higher F2 in the 1960's and 1980's data. We also show that the majority of these Fl and F2 changes were in the direction of the vowel positions of 1980's Standard Southern British speakers reported in Deterding (1997). Our general conclusion is that there is evidence of accent change within the same individual over time and that the Queen's vowels in the Christmas broadcasts have shifted in the direction of a more mainstream form of Received Pronunciation.