Rapid radiation of the inner Indo-European languages: An advanced approach to Indo-European lexicostatistics

In this article we present a new reconstruction of Indo-European phylogeny based on 13 110-item basic wordlists for protolanguages of IE subgroups (Proto-Germanic, Proto-Slavic, etc.) or ancient languages of the corresponding subgroups (Hittite, Ancient Greek, etc.). We apply reasonably formal techniques of linguistic data collection and post-processing (onomasiological reconstruction, derivational drift elimination, homoplastic optimization) that have been recently proposed or specially developed for the present study. We use sequential phylogenetic workflow and obtain a consensus tree based on several algorithms (Bayesian inference, maximum parsimony, neighbor joining; without topological constraints applied). The resulting tree topology and datings are entirely compatible with established expert views. Our main finding is the multifurcation of the Inner IE clade into four branches ca. 3357-2162 BC: (1) Greek-Armenian, (2) Albanian, (3) Italic-Germanic-Celtic, (4) Balto-Slavic-Indo-Iranian. The proposed radiation scenario may be reconciled with diverse opinions on Inner IE branchings previously expressed by Indo-Europeanists.