Prestopped nasals in Umbuygamu (Morrobolam): From prestopping to preaspiration

Abstract This article analyses prestopped nasals in Umbuygamu (also known as Morrobolam), a Lamalamic (< Paman < Pama-Nyungan) language of northeastern Australia. The analysis focuses on three features that are of typological interest. First, prestopped realizations have a plosive phase that is significantly longer than the nasal phase, and that is voiceless by default. While classic accounts of the origin of prestopping predict a short and voiced plosive phase, the existence of long and voiceless phases may be due to phonologization and typical location at a prosodic boundary, as suggested by work on parallel cases elsewhere in Australia, specifically in Arandic. Second, prestopped nasals also have preaspirated realizations in Morrobolam, which have not been reported in the literature on prestopping. These are typologically similar to voiceless nasals as found in some Tibeto-Burman languages, in particular the type with aspiration preceding the nasal. Third, there is significant variation in the nature of nasal plosion in prestopped realizations, with some speakers showing relatively long and loud bursts. I argue that these may form a pathway for the emergence of preaspiration from prestopping, with turbulence taking over from a hold-burst structure as the signature characteristic of the non-nasal phase. I also suggest that long and loud bursts may be due to a difference in the mechanics of velum opening, with a glottalic airstream aerodynamically reinforcing muscle-controlled opening of the velum.