• Identify non-adjacent triggers of segment alternation
• Become familiar with triggers, targets, and directionality in vowel harmony
• Describe the contexts in which each alternant appears
• Identify the best fit for a default alternant or underlying form
• Compose rules to derive other alternants from underlying forms
• Identify non-assimilatory cases of segment alternation
So far much of the phonological alternation we've witnessed has involved adjacent sounds, where one segment has an effect on the form of some other segment immediately next to it, either before or afterwards. Consonant assimilation, intervocalic effects, and palatalization are examples of such local phenomena. Some phonological patterns, however, do not clearly involve segments adapting to adjacent segments. In addition, the morphophonology of many languages allows non-adjacent segments to have an effect on each other.
The most common type of such effects is called vowel harmony, in which a vowel adopts some or all features of some nearby (but usually non-adjacent) vowel.
vowel harmony: a process in which vowels become similar or identical to nearby vowels.
Let us first explore some suffix alternations in Mongolian (Svantesson et al. 2005). Look over the data below, paying attention to the vowels in each suffix.
Exercise 4.1 Identify the alternants of each suffix.
The direct past suffix has four alternants: [ɮe], [ɮo], [ɮa], and [ɮɔ]. The causative has two alternants: [uɮ] and [ʊɮ].
Exercise 4.2 Describe the distribution of the causative. Pay attention to the vowels of the roots.
The [uɮ] alternant follows roots with the vowels [i, u, e, o, ui]. The [ʊɮ] alternant follows roots with the simple vowels [a, ʊ, ɔ], and with the diphthongs [ʊi], [ai], and [oi].
Since the vowel of the suffix changes as a function of the vowel of the root, we can call this an example of vowel harmony. In addition, we can infer that the vowels [i, u, e, o] share some feature, while [a, ʊ, ɔ] have some other feature, and it is this difference between the groups that determines the choice of the suffix. Sometimes we characterize the first group as consisting of tense vowels, while the second group is lax – this is a typical way of describing these vowels as they occur in English.