Diversity, competition, extinction: the ecophysics of language change

TL;DR

This paper reviews mathematical models of language change that draw parallels with ecological systems, highlighting universal patterns and the emerging ecological theory of language evolution.

Contribution

It synthesizes ecological and statistical physics models of language dynamics, emphasizing their simplicity and potential to reveal fundamental laws of language organization.

Findings

Languages exhibit ecological-like patterns of diversity and extinction.

Mathematical models can predict large-scale language organization.

Ecological theory provides a quantitative framework for understanding language change.

Abstract

As early indicated by Charles Darwin, languages behave and change very much like living species. They display high diversity, differentiate in space and time, emerge and disappear. A large body of literature has explored the role of information exchanges and communicative constraints in groups of agents under selective scenarios. These models have been very helpful in providing a rationale on how complex forms of communication emerge under evolutionary pressures. However, other patterns of large-scale organization can be described using mathematical methods ignoring communicative traits. These approaches consider shorter time scales and have been developed by exploiting both theoretical ecology and statistical physics methods. The models are reviewed here and include extinction, invasion, origination, spatial organization, coexistence and diversity as key concepts and are very simple in their defining rules. Such simplicity is used in order to catch the most fundamental laws of organization and those universal ingredients responsible for qualitative traits. The similarities between observed and predicted patterns indicate that an ecological theory of language is emerging, supporting (on a quantitative basis) its ecological nature, although key differences are also present. Here we critically review some recent advances lying and outline their implications and limitations as well as open problems for future research.