seminar series “Darwin’s Tongues – Evolution of Language”: "Extra-linguistic factors nudge language evolution (but language is not passive and fights back!)" - Dan Dediu
- Date: Nov 20, 2015
- Time: 11:00 AM - 12:00 PM (Local Time Germany)
- Speaker: Dan Dediu from the MPI for Psycholinguistics, Nijmegen, Netherlands
- Location: MPI Plön
- Room: Lecture hall
- Host: Miriam Liedvogel and Miriam Linnenbrink
Language does not evolve in an isolated manner, in its own purely cultural realm where the only factors that influence it are language internal. In fact, a series of extra-linguistic factors including latitude, altitude, humidity and deafness arguably have an impact on the way language evolves (diachronically) and on the patterns of linguistic diversity (synchronically). Therefore, I will argue that such small biases "nudge" the process of language evolution through its repeated use and transmission, playing a part in explaining the observed trajectories of language change and patterns of diversity.
Here, I will focus in particular on the potential effects that the anatomy and physiology of the vocal tract might have on speech production. More precisely, I will argue that not only are there vast amounts of inter-individual variation in the vocal tract (VT) which might affect speech production at the individual level, but that this variation is patterned across populations resulting in systematic cross-linguistic variation in phonetics and, ultimately, phonology. I will summarize the ongoing Genetic biases in language and speech (G[ɜ]bils) project, where we explore in multiple directions and across multiple disciplines the patterns of VT variation and its effects on cross-linguistic phonetic and phonological variation. As examples, I will highlight the work done on modeling the shape of the hard palate using Bézier curves for agent-based computer models of language evolution, the bio-mechanical exploration of the influence of the presence of an alveolar ridge on the production of click sounds, and the exploratory investigation of inter-population patterns and the genetic bases of normal inter-individual VT variation.
However, it must be stressed that while extra-linguistic factors might "nudge" language change and evolution, language is not passive but might fight back by changing the selection pressures to which our genomes must respond. This is a much more general evolutionary phenomenon covered by gene-culture co-evolution and (cultural) niche construction theories, and I will focus here on the case of the sign languages (and in particular the so-called emergent ones) as a powerful illustration that language can indeed be a powerful factor in changing the (biological) adaptive landscape.