Warm Climates and Sonority Classes Not Simply More Vowels and Fewer Consonants

Previous research has shown that speakers in warm-climate languages make use of relatively more vowels, and speakers in cold-climate languages relatively more consonants. The high sonority (audibility) of the vowel, and its adaptive value under certain conditions, have been invoked to account for its greater frequency in warmer climates. We show here, however, that the above generalization is over-broad, and that sound classes vary across climate zones in complex ways. One new finding is that speakers in warm-climate languages make more use of the so-called sonorant consonants, that is, consonants with some of the qualities of vowels. We offer a provisional framework that continues to find value in the concept of sonority and its relation to climate, but attempts to incorporate the new results and provide a more comprehensive explanation.