Linguistics 2021; 59(4): 949–979 Alexei S. Kassian*, Mikhail Zhivlov, George Starostin, Artem A. Trofimov, Petr A. Kocharov, Anna Kuritsyna and Mikhail N. Saenko Rapid radiation of the inner Indo-European languages: an advanced approach to Indo- European lexicostatistics https://doi.org/10.1515/ling-2020-0060 Received March 31, 2020; accepted August 21, 2020; published online June 18, 2021 Abstract: 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 phylo- genetic 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 *Corresponding author: Alexei S. Kassian, School of Advanced Studies in the Humanities, The Russian Presidential Academy of National Economy and Public Administration, Prospect Vernadskogo, 84, Bldg. 2, 119571, Moscow, Russia, E-mail:
[email protected] Mikhail Zhivlov, Institute for Oriental and Classical Studies, National Research University Higher School of Economics, Moscow, Russia; and Institute for Oriental and Classical Studies, Russian State University for the Humanities, Moscow, Russia, E-mail:
[email protected] George Starostin, Institute for Oriental and Classical Studies, National Research University Higher School of Economics, Moscow, Russia; and Santa Fe Institute, Santa Fe, NM, USA, E-mail:
[email protected] Artem A.