On the Evolution of Word Order

TL;DR

This paper investigates why many natural languages have a fixed word order by modeling language evolution, showing that fixed order is functionally advantageous and that additional linguistic features can reduce this necessity.

Contribution

It provides a theoretical and computational analysis demonstrating the evolutionary advantage of fixed word order in languages and how linguistic features influence this preference.

Findings

Fixed word order is shown to be evolutionarily optimal.

Adding case markers reduces the need for fixed word order.

The model aligns with typological observations.

Abstract

Most natural languages have a predominant or fixed word order. For example in English the word order is usually Subject-Verb-Object. This work attempts to explain this phenomenon as well as other typological findings regarding word order from a functional perspective. In particular, we examine whether fixed word order provides a functional advantage, explaining why these languages are prevalent. To this end, we consider an evolutionary model of language and demonstrate, both theoretically and using genetic algorithms, that a language with a fixed word order is optimal. We also show that adding information to the sentence, such as case markers and noun-verb distinction, reduces the need for fixed word order, in accordance with the typological findings.