Altitude and the distributional typology of language structure: Ejectives and beyond

Abstract

The first decades of the 21st century have witnessed a renewed interest in the relationship between language structure and the various social and ecological niches in which the languages of the world are used and against the background of which they evolved. In this context, Everett (2013) argued for direct geographical influences on the sound structure of languages. It was observed that ejective consonants, produced with a sudden burst of non-pulmonic air to a salient acoustic effect, tend to occur in high-altitude environments in which these sounds may be adaptive due to a reduced articulatory effort and/or to prevent desiccation. Here, we evaluate this claim and at the same time place it into a broader context. We observe that the distribution of another class of typologically unusual sounds, uvulars, is highly similar to that of ejectives, but that the proposed explanations are not available to account for the similar geographical patterning of uvulars. Hence, we test an alternative explanatory account that would posit indirect rather than direct environmental influences on language structure that are mediated by anthropological factors, in particular the relative sociolinguistic isolation of speech communities at the highest altitudes. Applying Bayesian Logistic Mixed Effects Regression to a large database of phonological inventories of the world’s languages, however, we do not find strong support for either a correlation of ejectives or uvulars with high-altitude environments, though the association is somewhat stronger for ejectives than uvulars. A phylogenetic exploration of the development of both classes of sounds in two large language families spoken in widely different environments, Indo-European and Sino-Tibetan, together with a qualitative assessment of the dedicated literature, in contrast, suggests a strong role of language contact rather than environmental factors.

The sounds of prehistoric speech

“…As in the case of the click-related hypothesis, however, this suggestion remains speculative. Recent work replicates the key finding in Everett [39] with a much larger sample of languages, finding a significant worldwide correlation between ejectives and altitudes [40]. However, that work also questions the interpretation of the distribution offered in Everett [39], while acknowledging that room for such an interpretation remains [40].…”

The Sound Systems of Languages Adapt, But to What Extent?

“…This high-altitude distribution was also recently supported with a much larger dataset, though the study in question also found support for a weaker association between uvular phonemes and high elevation. (Urban & Moran 2021) The latter association hints that the ejective-altitude correlation is likely spurious. In other work I test the frequency of ejective consonants in phonetically transcribed word lists from 1,991 dialects, once again using the ASJP database, along with numerous other consonant types.…”

“…Associations of this type can be used as starting points to further inquiry, though in the case of ejectives there are reasons to doubt that the association is due to the motivation suggested in Everett (2013). (Urban & Moran 2021) Figure 2. Locations of 176 dialects whose Swadesh-type word lists contain ejective consonants, out of 1,991 tested in Everett (in progress).…”

“…Brightness corresponds to the ratio of all consonants in a word list that are ejectives. See also Urban & Moran (2021).…”

“…(Of course, the distribution of ejectives could still be a historical coincidence, see e.g. Urban & Moran (2021)). The question, in this context, is whether certain effects on the vocal cords cause glottalization to be slightly more likely to be maintained when a glottal stop and an oral stop are initially fused in the speech of individuals.…”