Historical-Comparative Linguistics and Ecolinguistics: A Critical Review of Language Change, Contact, and Ecological Sustainability

Abstract

Historical-comparative linguistics and ecolinguistics have developed along largely separate trajectories for over two centuries, the former concerned with the reconstruction of proto-languages and the regularities of sound change, the latter with the discursive and material relationships between language and the natural world. Yet both fields converge on a shared premise: language is neither static nor autonomous but is shaped by, and in turn shapes, the ecological and social systems in which it is embedded. This review synthesises recent scholarship across both traditions, tracing developments in the comparative method, computational historical linguistics, language contact and borrowing, and the bibliometric consolidation of ecolinguistics as a distinct discipline oriented towards natural rather than purely social ecologies. It further examines the empirical evidence linking linguistic diversity to biological diversity, the accelerating pace of language endangerment and its parallels with species extinction, and the growing recognition of Indigenous languages as repositories of ecological knowledge relevant to conservation practice. The review identifies a persistent methodological gap between the quantitative rigour of computational historical linguistics and the qualitative, discourse-analytic orientation of much ecolinguistic scholarship, and argues that closer integration of these approaches could strengthen both the scientific credibility and the applied relevance of language-ecology research. Future directions, conclusions and limitations are discussed with reference to interdisciplinary collaboration, policy translation and the ethical stewardship of linguistic and biocultural heritage.