Morphemes, Phonetics and Lexical Items: The Case of the Scottish Vowel Length Rule.

We show that, in the Scottish Vowel Length Rule, the high vowels in the sequences /i#d/ and /##d/ are 68% longer than in the tautomorphemic /id/ and /ud/ sequences, while /ai#d/ is only 28% longer than /aid/. There is no quality difference associated with /i/ and /#/, but long and short /ai/ do differ in quality. Spectral analysis of F1 and F2 trajectories indicates that the prime difference in the vowels due to the SVLR appears to be the timing of formant movements, not the location of the targets in formant space. In the longer vowel of sighed, the rise towards a high front position starts at about 75ms-100ms into the vowel, and in the shorter vowel of side it is aligned nearer the start of the vowel. There are, moreover, genuine target differences which function as a marker of social class.