Investigating Obsolescence: Where are we now?

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On the face of it, language evolution and language obsolescence have little to do with each other. One seems concerned with the origins of things, while the other seems mainly about how they end. It is thus perhaps unsurprising that obsolescence has received relatively little attention in the field of language evolution. But this is not the right way to look at things, and researchers in each field would benefit greatly from a deeper and more nuanced understanding of the other. The purpose of this paper is to argue why this is so, and to suggest some specific benefits of such an exchange.

The study of language obsolescence is concerned with what happens when one language loses ground to competitors (Swiggers, 2007). The field of language evolution is concerned most obviously with the origins of language and the emergence of structure within language (Scott-Phillips & Kirby, 2010); but it is also concerned more broadly with the application of evolutionary thinking to studying language—to languages as complex adaptive systems in their own right (“Five Graces Group”, 2009); given that, the consequences of linguistic competition fit straightforwardly within the remit of the field. But language obsolescence is in fact also highly relevant to questions of origins and emergence—contact and competition can be a creative force in their own right. Indeed, work over the last decade on the Linguistic Niche Hypothesis (LNH; Dale & Lupyan, 2012) has paid a good deal of attention to population size and structure as explanatory variables in understanding grammatical typological patterns. The linguistic consequences of language obsolescence are among the better studied examples of this relationship and the field of language evolution would benefit greatly from a clearer understanding of it that goes beyond the seminal, but now quite outdated, work conducted in the 1960s and 1970s (e.g., Dorian, 1973). A fair amount of work on the LNH (e.g., Raviv, Meyer, & Lev-Ari, 2019) has employed innovative experimental methods in which participants learn and communicate with artificial languages (Roberts, 2017); but almost no work of this kind has been conducted with language obsolescence explicitly in mind (though see Baptista et al., 2016 for related work on contact). This represents an important gap to be filled. Doing so would allow hypotheses to be tested in the lab in a way that is otherwise impossible (see, e.g., Roberts and Sneller, 2020). This should benefit everyone involved. Language obsolescence is a part of language evolution and should be studied as such.