Volker Gast & Christoph Rzymski

(University of Jena)

Is there a (direct) influence of climate on language?

The recent years have seen a keen interest in correlations between linguistics data with geographic and climate data. For example, it has been observed that ejectives tend to occur in higher altitudes (Everett 2013), that tones are underrepresented in regions with dry or cold climate (Everett et al. 2016), and that consonant inventories vary with several climate variables, such as temperature, precipitation and tree cover (Maddieson and Coupé 2016). One of the main problems of these claims is that the linguistic variables in question – the presence of tone and ejectives, the size of consonant inventories, etc. – show spatial autocorrelation reflecting both genealogical relatedness and language contact. Even though most of the authors claim that they control for both genealogical and areal effects, the ‘areal factor’ remains a major problem. We intend to tackle this problem by using a graph-based approach and methods from machine learning. In addition to discussing the role of spatial autocorrelation in the data, we will address another central issue associated with the correlations in question: On the assumption that there are in fact correlations between geographic/climate data and linguistic data, how can they be explained? Maddieson & Coupé (2015) argue for the “acoustic adaptation hypothesis”, according to which sound systems tend to adapt to the local climate. A more realistic scenario, from our point of view, is that the effects of climate on language (if there is any) is indirect: Climate conditions may trigger migration, leading to specific demographic effects, which in turn may impact linguistic systems (e.g. when specific regions attract migration and consequently acquire a higher rate of language contact and second language acquisition). The question arises how these alternative hypotheses can be tested, on the basis of the data available at present.

Everett, C. (2013). “Evidence for direct geographic influences on linguistic sounds: The case of ejectives”. In: PLOS ONE 8.6.

Everett, C., D. Blasi, and S. Roberts (2016). “Language evolution and climate: the case of desiccation and tone”. In: Journal of Language Evolution 1.1, pp. 33–46.

Maddieson, I. and C. Coupé (2016). “Human spoken language diversity and the acoustic adaptation hypothesis”. In: The Journal of the Acoustical Society of America 25.