A paper by Gell-Mann & Ruhlen in PNAS this week conducts a phylogenetic analysis of word order in languages and concludes that SOV is the most likely ancestor language word order. The main conclusions from the analysis are:
(i) The word order in the ancestral language was SOV.
(ii) Except for cases of diffusion, the direction of syntactic change, when it occurs, has been for the most part SOV > SVO and, beyond that, SVO > VSO/VOS with a subsequent reversion to SVO occurring occasionally. Reversion to SOV occurs only through diffusion.
(iii) Diffusion, although important, is not the dominant process in the evolution of word order.
(iv) The two extremely rare word orders (OVS and OSV) derive directly from SOV.
This analysis agrees with Luke Maurtis‘ work on function and Uniform Information Density (blogged about here).
I’ll reserve judgement until I’ve read a paper, but we discussed this in typology today, and the general conclusion was along the lines of “if one could take a guess at the original word order, then placing money on SOV would be a good bet… whether it’s science is another question”. In fact, it’s almost as predictable as Gell-Mann teaming up with Ruhlen 😉 . But as I said, I’ll be good and wait until I’ve read the paper.