The relationship between vowel variation and vowel-to-vowel coarticulation across languages

The amount of coarticulatory vowel variation within a language may be dependent on the size and distribution of the vowel inventory within the vowel formant space [P. A. Keating and M. K. Huffman, Phonetica 41, 191–207 (1984)]. Similarly, it has been suggested that the extent of vowel-to-vowel coarticulation in a language varies in proportion to the degree of vowel variation within the language [S. Y. Manuel and R. A. Krakow, Haskins Status Report No. 77/78, 69–78 (1984)]. Manuel and Krakow supported this idea with evidence comparing Swahili and Shona (5-vowel systems) to English (12-vowel system). The present study compares vowel-to-vowel anticipatory and carryover coarticulation in Japanese and Hausa (10-vowel systems, with different vowel distributions) to German (14-vowel system). Three speakers of each language read bVbV “words” in lists and in frame sentences. The effects of phonemic vowel length and phrasal context on coarticulatory vowel distribution are also considered.