The distribution of phoneme inventory and language evolution

The number of phonemes varies widely among languages, ranging from about 10 to more than 140. The overall distribution of phonemes is positively skewed and can be reasonably approximated by the lognormal distribution. This distribution is generally associated with multiplicative processes from which model-dependent estimates of the rates of growth of language families and the phoneme inventory of individual languages can be obtained. Using the inventories in UPSID, one simple model is used to show that vowel and consonant inventories differ in their rates of growth. While other appropriate models should be considered, this general approach provides a means of learning more about phoneme change