Coarticulation and contrast in a vowel harmony system: coarticulatory propensity in Khalkha Mongolian V-C-V sequences
Vowel harmony has been understood to emerge when listeners fail to perceptually compensate for acoustic variation due to coarticulation. Assuming such an account, what explains the maintenance of non-harmonic domains in the grammar? Towards understanding this, we examine coarticulation within a synchronic system with well-established patterns of harmony and non-harmony. In Khalkha Mongolian, vowels in non-compound words share the features [ATR] and [round], harmony operating in the carryover (left-to-right) direction. The high-front vowel /i/ does not participate in harmony, giving “non-harmonic” VCV sequences. We quantify coarticulatory variation by comparing dependencies in first- and second-formant frequencies (F1&F2) of vowels in harmonic vs non-harmonic VCV sequences. Unlike the former, the latter show greater coarticulation in the anticipatory (right-to-left) direction—opposite to that of vowel harmony. /i/, which is transparent to harmony, demonstrates high coarticulatory resistance. We argue that in systems where vowel harmony is well-established, synchronic patterns of coarticulatory propensity serve to limit featuresharing in non-harmonic domains.