Thursday, November 27, 2003

Indo-European Languages: Cavalli-Sforza Was Right

It would seem that Luca Cavalli-Sforza and Colin Renfrew were right in hypothesizing that the spread of the European languages occurred by demic diffusion of Anatolean farmers.1

A family tree of Indo-European languages suggests they began to spread and split about 9,000 years ago. The finding hints that farmers in what is now Turkey drove the language boom - and not later Siberian horsemen, as some linguists reckon.

Russell Gray and Quentin Atkinson, of the University of Auckland in New Zealand use the rate at which words change to gauge the age of the tree's roots - just as biologists estimate a species' age from the rate of gene mutations. The differences between words, or DNA sequences, are a measure of how closely languages, or species, are related.

Gray and Atkinson analysed 87 languages from Irish to Afghan. Rather than compare entire dictionaries, they used a list of 200 words that are found in all cultures, such as 'I', 'hunt' and 'sky'. Words are better understood than grammar as a guide to language history; the same sentence structure can arise independently in different tongues.

The resulting tree matches many existing ideas about language development. Spanish and Portuguese come out as sisters, for example - both are cousins to German, and Hindi is a more distant relation to all three.

All other Indo-European languages split off from Hittite, the oldest recorded member of the group, between 8,000 and 10,000 years ago, the pair calculates.

Around this time, farming techniques began to spread out of Anatolia - now Turkey - across Europe and Asia, archaeological evidence shows. The farmers themselves may have moved, or natives may have adopted words along with agricultural technology. (emphasis added)

(1) For further details, see "The History and Geography of Human Genes", by L. Luca Cavalli-Sforza, Paolo Menozzi, and Alberto Piazza, 1994, Princeton University Press. ISBN 0-691-087540-4.