Prosodic effects on the planning of inserted /ɹ/ in Australian English

V1.V2 hiatus is disallowed in many languages. In several varieties of English, when V1 is non-high, hiatus may be resolved by glottalization or /ɹ/ insertion. However, it is not well understood why speakers choose one over the other. In addition, questions remain about how foot boundary influences the hiatus-breaking strategy and whether perceived /ɹ/ is a phonetic transition or segmental insertion. Using an elicited production task, we investigated the effect of foot boundary on hiatus resolution and examined whether perceived inserted /ɹ/ exerts co-articulatory influence on V1 onset as predicted if it is segmental. Hiatus contexts were constructed from two types of coda-less nouns to generate V1 (e.g. paw without orthographic 'r', door with orthographic 'r') followed by one of three onset-less prepositions ('under', 'above', 'of'). Foot boundary locations were manipulated in three metrical conditions to examine gradient influence of foot boundary proximity (e.g. 'This is the [paw] under the dog', 'This is the [paw a]bove the dog', 'This is the [paw of the] dog'). Results showed complementarity between glottalization and /ɹ/ insertion. Expanding the distance between the hiatus and foot boundary increased the use of /ɹ/ and decreased glottalization. F3 lowering at V1 onset occurred in perceived /ɹ/ contexts, providing acoustic evidence for inserted segmental /ɹ/.