Contrastive tonal alignment in falling contours in Shilluk

It has been assumed that tonal alignment is not contrastive in contour tones (e.g. Hyman 1988, Odden 1995, Yip 2002). However, Remijsen (2013) and DiCanio et al. (2014) have recently reported evidence for this configuration. In relation to this controversy, we report on an acoustic analysis of the tone system of Shilluk. The dataset is built around the contrast of Low vs . Early-aligned High Fall vs . Late-aligned High Fall vs . High in closed monosyllabic stems with a short vowel. The results support the hypothesis that tonal alignment is contrastive in falling contour tones in Shilluk: the two falling contours differ consistently and significantly in terms of tonal alignment, relative both to one another and to phonetically similar level-tone configurations. The falling contours do not differ significantly in terms of a number of other phonetic parameters (F0 height, size of F0 change, duration).