Two types of octave relationships in central Australian vocal music?

Five performance sections from four different Central Australian songlines with a melodic range larger than an octave have been analysed. Although octave ratios exist, they are limited to one octave interval in each songline: only the finalis has an ‘octave’ counterpart, other intervals in the upper melodic range are shown to be linear shifts of intervals in the lower range. There is evidence that the octave ratio is not treated as an octave in the common musical sense (octave identity) but much more as a specific ratio (as part of the characterization of the songlines). This helps considerably in understanding of how a musical system based on intricate patterns of linear (frequency difference) intervals can, at the same time, contain ratio intervals as essential elements without contradictions: this music does not seem to know a generalized principle of octave identity.