The sounds of prehistoric speech

Abstract

Evidence is reviewed for widespread phonological and phonetic tendencies in contemporary languages. The evidence is based largely on the frequency of sound types in word lists and in phoneme inventories across the world's languages. The data reviewed point to likely tendencies in the languages of the Upper Palaeolithic. These tendencies include the reliance on specific nasal and voiceless stop consonants, the relative dispreference for posterior voiced consonants and the use of peripheral vowels. More tenuous hypotheses related to prehistoric languages are also reviewed. These include the propositions that such languages lacked labiodental consonants and relied more heavily on vowels, when contrasted to many contemporary languages. Such hypotheses suggest speech has adapted to subtle pressures that may in some cases vary across populations. This article is part of the theme issue 'Reconstructing prehistoric languages'.

Keywords: Upper Palaeolithic; consonants; phonemes; prehistoric speech; vowels.

Figure 1.

This chart represents the pulmonic consonants of the International Phonetic Alphabet. Each cell represents one consonant on the IPA chart. Cell brightness corresponds to a consonant's frequency as a phoneme across the world's languages, based on the data in PHOIBLE, a database with sound-inventory information for 2186 languages. Black cells correspond to sounds that do not occur because of physiological limitations.

Figure 2.

Average disparity in usage rates of plosive consonants at the same place of articulation, for 312 language lineages. Based on Everett [26]. The lineages are organized alphabetically (see electronic supplementary material for list). Voiced plosives become relatively less common as place of articulation approaches the glottis. The mean difference in the frequencies of [k] and [g], calculated as proportions of all transcribed consonants, is 0.06. This is the average disparity obtained across the 312 lineages represented by 3341 documented language varieties or doculects. [k] is used about three times as much as [g] across all lineages, [t] is about two times more common than [d], while [p] and [b] are equifrequent. (See [, p. e6].)

Figure 3.

Ridgeline plot representing the proportion of sounds that are vowels, i.e. ‘vowel ratios’, across the 35 language families with at least 10 representative samples in the dataset used in Everett [28]. Each ‘hill’ represents a density distribution of the vowel proportions across the word lists for a given family. (Gaussian density plot used.) Families are ordered from highest mean vowel ratio (top) to lowest.

Figure 4.

Heatmap of the global association between vowel ratios and ambient humidity, based on data for 4012 word lists from 2632 distinct languages [28]. This association may owe itself in part to the minor increase in effort required of vocal cord vibration in dry contexts. Pseudo-R² value is based on the β-regression analysis in Everett [28].