Phylogenetic trees: Grammar versus vocabulary

Abstract

Traditionally, genealogical relationships between languages are established on the basis of phonetic and lexical data. The question whether genealogical relationships among languages can be defined based on grammatical data remains unanswered. The objective of this article is to compare two phylogenetic trees: one built using the Automated Similarity Judgment Program (ASJP) project, and one using the World Atlas of Language Structures (WALS). We include data from WALS representing 27 languages from 5 language families of all continents that are deemed to be sufficiently well described. A Hamming distance matrix was calculated for all languages under study, and, based on the matrix, a phylogenetic tree was built. The trees built according to WALS and ASJP data are compared with each other and with a tree built by the classical comparative historical method. Both the ASJP-based tree and the WALS-based tree have their advantages and disadvantages. The ASJP-based tree is a good reflection of the evolutionary divergence of languages. Similarities of languages as calculated based on the typological database of WALS can provide information on the history of languages both in terms of genealogical descent and contact with other languages. The ASJP-based tree reflects genealogical relationship well at a relatively small time depth, while the WALS-based tree reflects genealogical relationship well at large time intervals. We suggest a new variant of a phylogenetic tree that includes information on both the divergence (ASJP project) and the convergence (WALS project) of languages, combining the benefits of both of these trees, although the problem of borrowings remains. The present research reveals prospects for future studies of genealogical relations among languages based on large-scale descriptions of their grammatical structures.

Keywords

• typology
• quantitative linguistics
• computational linguistics
• historical linguistics
• phylogenetics