An innovative computational approach applied by an international team of linguists sheds new light on the origins of Indo-European languages.
The Indo-European languages belong to one of the widest spread language families of the world. For the last two millennia, many of these languages have been written, and their history is relatively clear. But controversy remains about the time and place of the origins of the family.
The majority view in historical linguistics is that the homeland of Indo-European is located in the Pontic steppes – present day Ukraine – around 6,000 years ago. The evidence for this comes from linguistic paleontology: in particular, certain words to do with the technology of wheeled vehicles are arguably present across all the branches of the Indo-European family; and archaeology tells us that wheeled vehicles arose no earlier than this date.
The minority view links the origins of Indo-European with the spread of farming from Anatolia 8,000-9,500 years ago. The team’s innovative Bayesian phylogeographic analysis of Indo-European linguistic and spatial data, including basic vocabulary data from 103 ancient and contemporary Indo-European languages, decisively supports this theory. The linguists report their results in a paper in the journal Science.
The analysis combines a model of the evolution of the lexicons of individual languages with an explicit spatial model of the dispersal of the speakers of those languages. Known events in the past are used to calibrate the inferred family tree against time.
The lexical data used in this analysis come from the Indo-European Lexical Cognacy Database. This database provides a large, high-quality collection of language data suitable for phylogenetic analysis. Beyond the intrinsic interest of uncovering the history of language families and their speakers, phylogenetic trees are crucially important for understanding evolution and diversity in many human sciences, from syntax and semantics to social structure.
Bibliographic information: Bouckaert et al. 2012. Mapping the Origins and Expansion of the Indo-European Language Family. Science, vol. 337, no. 6097, pp. 957-960; doi: 10.1126/science.1219669